An Introduction to Confidence Intervals for Both Statistical Estimates and Effect Sizes.
ERIC Educational Resources Information Center
Capraro, Mary Margaret
This paper summarizes methods of estimating confidence intervals, including classical intervals and intervals for effect sizes. The recent American Psychological Association (APA) Task Force on Statistical Inference report suggested that confidence intervals should always be reported, and the fifth edition of the APA "Publication Manual"…
Graphing within-subjects confidence intervals using SPSS and S-Plus.
Wright, Daniel B
2007-02-01
Within-subjects confidence intervals are often appropriate to report and to display. Loftus and Masson (1994) have reported methods to calculate these, and their use is becoming common. In the present article, procedures for calculating within-subjects confidence intervals in SPSS and S-Plus are presented (an R version is on the accompanying Web site). The procedure in S-Plus allows the user to report the bias corrected and adjusted bootstrap confidence intervals as well as the standard confidence intervals based on traditional methods. The presented code can be easily altered to fit the individual user's needs.
The P Value Problem in Otolaryngology: Shifting to Effect Sizes and Confidence Intervals.
Vila, Peter M; Townsend, Melanie Elizabeth; Bhatt, Neel K; Kao, W Katherine; Sinha, Parul; Neely, J Gail
2017-06-01
There is a lack of reporting effect sizes and confidence intervals in the current biomedical literature. The objective of this article is to present a discussion of the recent paradigm shift encouraging the use of reporting effect sizes and confidence intervals. Although P values help to inform us about whether an effect exists due to chance, effect sizes inform us about the magnitude of the effect (clinical significance), and confidence intervals inform us about the range of plausible estimates for the general population mean (precision). Reporting effect sizes and confidence intervals is a necessary addition to the biomedical literature, and these concepts are reviewed in this article.
Glass, Deborah C; Sim, Malcolm R; Kelsall, Helen L; Ikin, Jill F; McKenzie, Dean; Forbes, Andrew; Ittak, Peter
2006-07-01
This study identified chemical and environmental exposures specifically associated with the 1991 Persian Gulf War. Exposures were self-reported in a postal questionnaire, in the period of 2000-2002, by 1,424 Australian male Persian Gulf War veterans in relation to their 1991 Persian Gulf War deployment and by 625 Persian Gulf War veterans and 514 members of a military comparison group in relation to other active deployments. Six of 28 investigated exposures were experienced more frequently during the Persian Gulf War than during other deployments; these were exposure to smoke (odds ratio [OR], 4.4; 95% confidence interval, 3.0-6.6), exposure to dust (OR, 3.7; 95% confidence interval, 2.6-5.3), exposure to chemical warfare agents (OR, 3.9; 95% confidence interval, 2.1-7.9), use of respiratory protective equipment (OR, 13.6; 95% confidence interval, 7.6-26.8), use of nuclear, chemical, and biological protective suits (OR, 8.9; 95% confidence interval, 5.4-15.4), and entering/inspecting enemy equipment (OR, 3.1; 95% confidence interval, 2.1-4.8). Other chemical and environmental exposures were not specific to the Persian Gulf War deployment but were also reported in relation to other deployments. The number of exposures reported was related to service type and number of deployments but not to age or rank.
Facebook and Twitter vaccine sentiment in response to measles outbreaks.
Deiner, Michael S; Fathy, Cherie; Kim, Jessica; Niemeyer, Katherine; Ramirez, David; Ackley, Sarah F; Liu, Fengchen; Lietman, Thomas M; Porco, Travis C
2017-11-01
Social media posts regarding measles vaccination were classified as pro-vaccination, expressing vaccine hesitancy, uncertain, or irrelevant. Spearman correlations with Centers for Disease Control and Prevention-reported measles cases and differenced smoothed cumulative case counts over this period were reported (using time series bootstrap confidence intervals). A total of 58,078 Facebook posts and 82,993 tweets were identified from 4 January 2009 to 27 August 2016. Pro-vaccination posts were correlated with the US weekly reported cases (Facebook: Spearman correlation 0.22 (95% confidence interval: 0.09 to 0.34), Twitter: 0.21 (95% confidence interval: 0.06 to 0.34)). Vaccine-hesitant posts, however, were uncorrelated with measles cases in the United States (Facebook: 0.01 (95% confidence interval: -0.13 to 0.14), Twitter: 0.0011 (95% confidence interval: -0.12 to 0.12)). These findings may result from more consistent social media engagement by individuals expressing vaccine hesitancy, contrasted with media- or event-driven episodic interest on the part of individuals favoring current policy.
Interpretation of Confidence Interval Facing the Conflict
ERIC Educational Resources Information Center
Andrade, Luisa; Fernández, Felipe
2016-01-01
As literature has reported, it is usual that university students in statistics courses, and even statistics teachers, interpret the confidence level associated with a confidence interval as the probability that the parameter value will be between the lower and upper interval limits. To confront this misconception, class activities have been…
Reporting Confidence Intervals and Effect Sizes: Collecting the Evidence
ERIC Educational Resources Information Center
Zientek, Linda Reichwein; Ozel, Z. Ebrar Yetkiner; Ozel, Serkan; Allen, Jeff
2012-01-01
Confidence intervals (CIs) and effect sizes are essential to encourage meta-analytic thinking and to accumulate research findings. CIs provide a range of plausible values for population parameters with a degree of confidence that the parameter is in that particular interval. CIs also give information about how precise the estimates are. Comparison…
Confidence Intervals for Effect Sizes: Applying Bootstrap Resampling
ERIC Educational Resources Information Center
Banjanovic, Erin S.; Osborne, Jason W.
2016-01-01
Confidence intervals for effect sizes (CIES) provide readers with an estimate of the strength of a reported statistic as well as the relative precision of the point estimate. These statistics offer more information and context than null hypothesis statistic testing. Although confidence intervals have been recommended by scholars for many years,…
Confidence Intervals for Proportion Estimates in Complex Samples. Research Report. ETS RR-06-21
ERIC Educational Resources Information Center
Oranje, Andreas
2006-01-01
Confidence intervals are an important tool to indicate uncertainty of estimates and to give an idea of probable values of an estimate if a different sample from the population was drawn or a different sample of measures was used. Standard symmetric confidence intervals for proportion estimates based on a normal approximation can yield bounds…
A Comparison of Methods for Estimating Confidence Intervals for Omega-Squared Effect Size
ERIC Educational Resources Information Center
Finch, W. Holmes; French, Brian F.
2012-01-01
Effect size use has been increasing in the past decade in many research areas. Confidence intervals associated with effect sizes are encouraged to be reported. Prior work has investigated the performance of confidence interval estimation with Cohen's d. This study extends this line of work to the analysis of variance case with more than two…
Virk, Jasveer; Liew, Zeyan; Olsen, Jørn; Nohr, Ellen A; Catov, Janet M; Ritz, Beate
2016-08-01
To evaluate whether early folic acid supplementation during pregnancy prevents diagnosis of autism spectrum disorders in offspring. Information on autism spectrum disorder diagnosis was obtained from the National Hospital Register and the Central Psychiatric Register. We estimated risk ratios for autism spectrum disorders for children whose mothers took folate or multivitamin supplements from 4 weeks prior from the last menstrual period through to 8 weeks after the last menstrual period (-4 to 8 weeks) by three 4-week periods. We did not find an association between early folate or multivitamin intake for autism spectrum disorder (folic acid-adjusted risk ratio: 1.06, 95% confidence interval: 0.82-1.36; multivitamin-adjusted risk ratio: 1.00, 95% confidence interval: 0.82-1.22), autistic disorder (folic acid-adjusted risk ratio: 1.18, 95% confidence interval: 0.76-1.84; multivitamin-adjusted risk ratio: 1.22, 95% confidence interval: 0.87-1.69), Asperger's syndrome (folic acid-adjusted risk ratio: 0.85, 95% confidence interval: 0.46-1.53; multivitamin-adjusted risk ratio: 0.95, 95% confidence interval: 0.62-1.46), or pervasive developmental disorder-not otherwise specified (folic acid-adjusted risk ratio: 1.07, 95% confidence interval: 0.75-1.54; multivitamin: adjusted risk ratio: 0.87, 95% confidence interval: 0.65-1.17) compared with women reporting no supplement use in the same period. We did not find any evidence to corroborate previous reports of a reduced risk for autism spectrum disorders in offspring of women using folic acid supplements in early pregnancy. © The Author(s) 2015.
Depressive symptoms in nonresident african american fathers and involvement with their sons.
Davis, R Neal; Caldwell, Cleopatra Howard; Clark, Sarah J; Davis, Matthew M
2009-12-01
Our objective was to determine whether paternal depressive symptoms were associated with less father involvement among African American fathers not living with their children (ie, nonresident fathers). We analyzed survey data for 345 fathers enrolled in a program for nonresident African American fathers and their preteen sons. Father involvement included measures of contact, closeness, monitoring, communication, and conflict. We used bivariate analyses and multivariate logistic regression analysis to examine associations between father involvement and depressive symptoms. Thirty-six percent of fathers reported moderate depressive symptoms, and 11% reported severe depressive symptoms. In bivariate analyses, depressive symptoms were associated with less contact, less closeness, low monitoring, and increased conflict. In multivariate analyses controlling for basic demographic features, fathers with moderate depressive symptoms were more likely to have less contact (adjusted odds ratio: 1.7 [95% confidence interval: 1.1-2.8]), less closeness (adjusted odds ratio: 2.1 [95% confidence interval: 1.3-3.5]), low monitoring (adjusted odds ratio: 2.7 [95% confidence interval: 1.4-5.2]), and high conflict (adjusted odds ratio: 2.1 [95% confidence interval: 1.2-3.6]). Fathers with severe depressive symptoms also were more likely to have less contact (adjusted odds ratio: 3.1 [95% confidence interval: 1.4-7.2]), less closeness (adjusted odds ratio: 2.6 [95% confidence interval: 1.2-5.7]), low monitoring (adjusted odds ratio: 2.8 [95% confidence interval: 1.1-7.1]), and high conflict (adjusted odds ratio: 2.6 [95% confidence interval: 1.1-5.9]). Paternal depressive symptoms may be an important, but modifiable, barrier for nonresident African American fathers willing to be more involved with their children.
Terry, Leann; Kelley, Ken
2012-11-01
Composite measures play an important role in psychology and related disciplines. Composite measures almost always have error. Correspondingly, it is important to understand the reliability of the scores from any particular composite measure. However, the point estimates of the reliability of composite measures are fallible and thus all such point estimates should be accompanied by a confidence interval. When confidence intervals are wide, there is much uncertainty in the population value of the reliability coefficient. Given the importance of reporting confidence intervals for estimates of reliability, coupled with the undesirability of wide confidence intervals, we develop methods that allow researchers to plan sample size in order to obtain narrow confidence intervals for population reliability coefficients. We first discuss composite reliability coefficients and then provide a discussion on confidence interval formation for the corresponding population value. Using the accuracy in parameter estimation approach, we develop two methods to obtain accurate estimates of reliability by planning sample size. The first method provides a way to plan sample size so that the expected confidence interval width for the population reliability coefficient is sufficiently narrow. The second method ensures that the confidence interval width will be sufficiently narrow with some desired degree of assurance (e.g., 99% assurance that the 95% confidence interval for the population reliability coefficient will be less than W units wide). The effectiveness of our methods was verified with Monte Carlo simulation studies. We demonstrate how to easily implement the methods with easy-to-use and freely available software. ©2011 The British Psychological Society.
Confidence Intervals for Weighted Composite Scores under the Compound Binomial Error Model
ERIC Educational Resources Information Center
Kim, Kyung Yong; Lee, Won-Chan
2018-01-01
Reporting confidence intervals with test scores helps test users make important decisions about examinees by providing information about the precision of test scores. Although a variety of estimation procedures based on the binomial error model are available for computing intervals for test scores, these procedures assume that items are randomly…
Faes, L; Bodmer, N S; Bachmann, L M; Thiel, M A; Schmid, M K
2014-07-01
To clarify the screening potential of the Amsler grid and preferential hyperacuity perimetry (PHP) in detecting or ruling out wet age-related macular degeneration (AMD). Medline, Scopus and Web of Science (by citation of reference) were searched. Checking of reference lists of review articles and of included articles complemented electronic searches. Papers were selected, assessed, and extracted in duplicate. Systematic review and meta-analysis. Twelve included studies enrolled 903 patients and allowed constructing 27 two-by-two tables. Twelve tables reported on the Amsler grid and its modifications, twelve tables reported on the PHP, one table assessed the MCPT and two tables assessed the M-charts. All but two studies had a case-control design. The pooled sensitivity of studies assessing the Amsler grid was 0.78 (95% confidence intervals; 0.64-0.87), and the pooled specificity was 0.97 (95% confidence intervals; 0.91-0.99). The corresponding positive and negative likelihood ratios were 23.1 (95% confidence intervals; 8.4-64.0) and 0.23 (95% confidence intervals; 0.14-0.39), respectively. The pooled sensitivity of studies assessing the PHP was 0.85 (95% confidence intervals; 0.80-0.89), and specificity was 0.87 (95% confidence intervals; 0.82-0.91). The corresponding positive and negative likelihood ratios were 6.7 (95% confidence intervals; 4.6-9.8) and 0.17 (95% confidence intervals; 0.13-0.23). No pooling was possible for MCPT and M-charts. Results from small preliminary studies show promising test performance characteristics both for the Amsler grid and PHP to rule out wet AMD in the screening setting. To what extent these findings can be transferred to a real clinic practice still needs to be established.
Coefficient Alpha Bootstrap Confidence Interval under Nonnormality
ERIC Educational Resources Information Center
Padilla, Miguel A.; Divers, Jasmin; Newton, Matthew
2012-01-01
Three different bootstrap methods for estimating confidence intervals (CIs) for coefficient alpha were investigated. In addition, the bootstrap methods were compared with the most promising coefficient alpha CI estimation methods reported in the literature. The CI methods were assessed through a Monte Carlo simulation utilizing conditions…
Code of Federal Regulations, 2012 CFR
2012-07-01
... confidence interval using Equations D-1 and D-2. Report the zero drift as the sum of the absolute mean value... confidence interval using Equations D-1 and D-2. Report the zero drift as the sum of the absolute mean and... operation when the pollutant concentration at the time for the measurement is zero. 1.6Calibration Drift...
Code of Federal Regulations, 2014 CFR
2014-07-01
... confidence interval using Equations D-1 and D-2. Report the zero drift as the sum of the absolute mean value... confidence interval using Equations D-1 and D-2. Report the zero drift as the sum of the absolute mean and... operation when the pollutant concentration at the time for the measurement is zero. 1.6Calibration Drift...
Code of Federal Regulations, 2013 CFR
2013-07-01
... confidence interval using Equations D-1 and D-2. Report the zero drift as the sum of the absolute mean value... confidence interval using Equations D-1 and D-2. Report the zero drift as the sum of the absolute mean and... operation when the pollutant concentration at the time for the measurement is zero. 1.6Calibration Drift...
NASA Astrophysics Data System (ADS)
Schuckers, Michael E.; Hawley, Anne; Livingstone, Katie; Mramba, Nona
2004-08-01
Confidence intervals are an important way to assess and estimate a parameter. In the case of biometric identification devices, several approaches to confidence intervals for an error rate have been proposed. Here we evaluate six of these methods. To complete this evaluation, we simulate data from a wide variety of parameter values. This data are simulated via a correlated binary distribution. We then determine how well these methods do at what they say they do: capturing the parameter inside the confidence interval. In addition, the average widths of the various confidence intervals are recorded for each set of parameters. The complete results of this simulation are presented graphically for easy comparison. We conclude by making a recommendation regarding which method performs best.
Confidence Intervals for Assessing Heterogeneity in Generalized Linear Mixed Models
ERIC Educational Resources Information Center
Wagler, Amy E.
2014-01-01
Generalized linear mixed models are frequently applied to data with clustered categorical outcomes. The effect of clustering on the response is often difficult to practically assess partly because it is reported on a scale on which comparisons with regression parameters are difficult to make. This article proposes confidence intervals for…
ERIC Educational Resources Information Center
Zientek, Linda Reichwein; Yetkiner, Z. Ebrar; Thompson, Bruce
2010-01-01
The authors report the contextualization of effect sizes within mathematics anxiety research, and more specifically within research using the Mathematics Anxiety Rating Scale (MARS) and the MARS for Adolescents (MARS-A). The effect sizes from 45 studies were characterized by graphing confidence intervals (CIs) across studies involving (a) adults…
Estimating Standardized Linear Contrasts of Means with Desired Precision
ERIC Educational Resources Information Center
Bonett, Douglas G.
2009-01-01
L. Wilkinson and the Task Force on Statistical Inference (1999) recommended reporting confidence intervals for measures of effect sizes. If the sample size is too small, the confidence interval may be too wide to provide meaningful information. Recently, K. Kelley and J. R. Rausch (2006) used an iterative approach to computer-generate tables of…
Duncan, Michael J; Eyre, Emma Lj; Bryant, Elizabeth; Seghers, Jan; Galbraith, Niall; Nevill, Alan M
2017-04-01
Overall, 544 children (mean age ± standard deviation = 14.2 ± .94 years) completed self-report measures of physical activity goal content, behavioral regulations, and physical activity behavior. Body mass index was determined from height and mass. The indirect effect of intrinsic goal content on physical activity was statistically significant via autonomous ( b = 162.27; 95% confidence interval [89.73, 244.70]), but not controlled motivation ( b = 5.30; 95% confidence interval [-39.05, 45.16]). The indirect effect of extrinsic goal content on physical activity was statistically significant via autonomous ( b = 106.25; 95% confidence interval [63.74, 159.13]) but not controlled motivation ( b = 17.28; 95% confidence interval [-31.76, 70.21]). Weight status did not alter these findings.
Hostility and the risk of peptic ulcer in the GAZEL cohort.
Lemogne, Cédric; Schuster, Jean-Pierre; Levenstein, Susan; Melchior, Maria; Nabi, Hermann; Ducimetière, Pierre; Limosin, Frédéric; Goldberg, Marcel; Zins, Marie; Consoli, Silla M
2015-02-01
Evidence for an association between hostility and peptic ulcer mainly relies on cross-sectional studies. Prospective studies are rare and have not used a validated measure of hostility. This prospective study aimed to examine the association between hostility and peptic ulcer in the large-scale French GAZEL cohort. In 1993, 14,674 participants completed the Buss and Durkee Hostility Inventory. Participants were annually followed-up from 1994 to 2011. Diagnosis of peptic ulcer was self-reported. The association between hostility scores and ulcer incidence was measured by hazard ratios (HR) and 95% confidence intervals computed through Cox regression. Among 13,539 participants free of peptic ulcer history at baseline, 816 reported a peptic ulcer during a mean follow-up of 16.8 years. Adjusting for potential confounders, including smoking, occupational grade, and a proxy for nonsteroidal anti-inflammatory drug exposure, ulcer incidence was positively associated with total hostility (HR per SD: 1.23, confidence interval: 1.14-1.31), behavioral hostility (HR per SD: 1.13, confidence interval: 1.05-1.21), cognitive hostility (HR per SD: 1.26, confidence interval: 1.18-1.35), and irritability (HR per SD: 1.20, confidence interval: 1.12-1.29). The risk of peptic ulcer increased from the lowest to the highest quartile for all hostility measures (p for linear trend < .05). Hostility might be associated with an increased risk of peptic ulcer. Should these results be replicated, further studies would be needed to explore the underlying mechanisms.
Taichi exercise for self-rated sleep quality in older people: a systematic review and meta-analysis.
Du, Shizheng; Dong, Jianshu; Zhang, Heng; Jin, Shengji; Xu, Guihua; Liu, Zengxia; Chen, Lixia; Yin, Haiyan; Sun, Zhiling
2015-01-01
Self-reported sleep disorders are common in older adults, resulting in serious consequences. Non-pharmacological measures are important complementary interventions, among which Taichi exercise is a popular alternative. Some experiments have been performed; however, the effect of Taichi exercise in improving sleep quality in older people has yet to be validated by systematic review. Using systematic review and meta-analysis, this study aimed to examine the efficacy of Taichi exercise in promoting self-reported sleep quality in older adults. Systematic review and meta-analysis of randomized controlled studies. 4 English databases: Pubmed, Cochrane Library, Web of Science and CINAHL, and 4 Chinese databases: CBMdisc, CNKI, VIP, and Wanfang database were searched through December 2013. Two reviewers independently selected eligible trials, conducted critical appraisal of the methodological quality by using the quality appraisal criteria for randomized controlled studies recommended by Cochrane Handbook. A standardized data form was used to extract information. Meta-analysis was performed. Five randomized controlled studies met inclusion criteria. All suffered from some methodological flaws. The results of this study showed that Taichi has large beneficial effect on sleep quality in older people, as indicated by decreases in the global Pittsburgh Sleep Quality Index score [standardized mean difference=-0.87, 95% confidence intervals (95% confidence interval) (-1.25, -0.49)], as well as its sub-domains of subjective sleep quality [standardized mean difference=-0.83, 95% confidence interval (-1.08, -0.57)], sleep latency [standardized mean difference=-0.75, 95% confidence interval (-1.42, -0.07)], sleep duration [standardized mean difference=-0.55, 95% confidence interval (-0.90, -0.21)], habitual sleep efficiency [standardized mean difference=-0.49, 95% confidence interval (-0.74, -0.23)], sleep disturbance [standardized mean difference=-0.44, 95% confidence interval (-0.69, -0.19)], and daytime dysfunction [standardized mean difference=-0.34, 95% confidence interval (-0.59, -0.09)]. Daytime sleepiness improvement was also observed. Weak evidence shows that Taichi exercise has a beneficial effect in improving self-rated sleep quality for older adults, suggesting that Taichi could be an effective alternative and complementary approach to existing therapies for older people with sleep problems. More rigorous experimental studies are required. Copyright © 2014 Elsevier Ltd. All rights reserved.
Statin therapy in lower limb peripheral arterial disease: Systematic review and meta-analysis.
Antoniou, George A; Fisher, Robert K; Georgiadis, George S; Antoniou, Stavros A; Torella, Francesco
2014-11-01
To investigate and analyse the existing evidence supporting statin therapy in patients with lower limb atherosclerotic arterial disease. A systematic search of electronic information sources was undertaken to identify studies comparing cardiovascular outcomes in patients with lower limb peripheral arterial disease treated with a statin and those not receiving a statin. Estimates were combined applying fixed- or random-effects models. Twelve observational cohort studies and two randomised trials reporting 19,368 patients were selected. Statin therapy was associated with reduced all-cause mortality (odds ratio 0.60, 95% confidence interval 0.46-0.78) and incidence of stroke (odds ratio 0.77, 95% confidence interval 0.67-0.89). A trend towards improved cardiovascular mortality (odds ratio 0.62, 95% confidence interval 0.35-1.11), myocardial infarction (odds ratio 0.62, 95% confidence interval 0.38-1.01), and the composite of death/myocardial infarction/stroke (odds ratio 0.91, 95% confidence interval 0.81-1.03), was identified. Meta-analyses of studies performing adjustments showed decreased all-cause mortality in statin users (hazard ratio 0.77, 95% confidence interval 0.68-0.86). Evidence supporting statins' protective role in patients with lower limb peripheral arterial disease is insufficient. Statin therapy seems to be effective in reducing all-cause mortality and the incidence cerebrovascular events in patients diagnosed with peripheral arterial disease. Copyright © 2014 Elsevier Inc. All rights reserved.
Zahra, J; Ford, T; Jodrell, D
2014-07-01
Previous research has established that poor diets and eating patterns are associated with numerous adverse health outcomes. This study explored the relationships between two specific eating behaviours (daily junk food consumption and irregular eating) and self-reported physical and mental health of secondary school children, and their association with perceived parenting and child health. 10 645 participants aged between 12 and 16 completed measures of junk food consumption, irregular eating, parental style, and mental and physical health through the use of an online survey implemented within 30 schools in a large British city. 2.9% of the sample reported never eating regularly and while 17.2% reported daily consumption of junk food. Young people who reported eating irregularly and consuming junk food daily were at a significantly greater risk of poorer mental (OR 5.41, 95% confidence interval 4.03-7.25 and 2.75, 95% confidence interval 1.99-3.78) and physical health (OR 4.56, 95% confidence interval 3.56-5.85 and 2.00, 95% confidence interval 1.63-2.47). Authoritative parenting was associated with healthier eating behaviours, and better mental and physical health in comparison to other parenting styles. A worrying proportion of secondary school children report unhealthy eating behaviours, particularly daily consumption of junk food, which may be associated with poorer mental and physical health. Parenting style may influence dietary habits. Interventions to improve diet may be more beneficial if also they address parenting strategies and issues related to mental and physical health. © 2013 John Wiley & Sons Ltd.
Disordered eating in entry-level military personnel.
Warner, Christopher; Warner, Carolynn; Matuszak, Theresa; Rachal, James; Flynn, Julianne; Grieger, Thomas A
2007-02-01
The goal was to determine the prevalence of and risk factors for disordered eating in an entry-level U.S. Army population. A cross-sectional survey of advanced individual training U.S. Army soldiers at Aberdeen Proving Ground, Maryland, was performed with an anonymous self-report survey containing demographic factors, history (including abuse and psychiatric treatment), and Eating Attitudes Test-26. Of 1,184 advanced individual training soldiers approached, 1090 participated. The response rate was 91.2% (955 men and 135 women). Forty percent were overweight (body mass index of > or =25), 11% reported a psychiatric history, 26% reported a history of abuse, and 9.8% endorsed disordered eating (male, 7.0%; female, 29.6%), as defined by Eating Attitudes Test-26. Factors that placed soldiers at higher risk for disordered eating were female gender (odds ratio, 5.63; 95% confidence interval, 3.32-9.57; p < 0.00005), overweight (odds ratio, 3.06; 95% confidence interval, 1.92-4.89; p < 0.00005), previous psychiatric treatment (odds ratio, 1.87; 95% confidence interval, 1.04-3.36; p = 0.035), and history of verbal abuse (odds ratio, 2.02; 95% confidence interval, 1.16-3.51; p = 0.014). Our study shows a higher than expected rate of disordered eating in advanced individual training soldiers with identifiable risk factors. This indicates an important need for further study, effective screening, preventive counseling, and early intervention for treatment.
Liu, Jen-Pei; Lu, Li-Tien; Liao, C T
2009-09-01
Intermediate precision is one of the most important characteristics for evaluation of precision in assay validation. The current methods for evaluation of within-device precision recommended by the Clinical Laboratory Standard Institute (CLSI) guideline EP5-A2 are based on the point estimator. On the other hand, in addition to point estimators, confidence intervals can provide a range for the within-device precision with a probability statement. Therefore, we suggest a confidence interval approach for assessment of the within-device precision. Furthermore, under the two-stage nested random-effects model recommended by the approved CLSI guideline EP5-A2, in addition to the current Satterthwaite's approximation and the modified large sample (MLS) methods, we apply the technique of generalized pivotal quantities (GPQ) to derive the confidence interval for the within-device precision. The data from the approved CLSI guideline EP5-A2 illustrate the applications of the confidence interval approach and comparison of results between the three methods. Results of a simulation study on the coverage probability and expected length of the three methods are reported. The proposed method of the GPQ-based confidence intervals is also extended to consider the between-laboratories variation for precision assessment.
ERIC Educational Resources Information Center
Ruscio, John; Mullen, Tara
2012-01-01
It is good scientific practice to the report an appropriate estimate of effect size and a confidence interval (CI) to indicate the precision with which a population effect was estimated. For comparisons of 2 independent groups, a probability-based effect size estimator (A) that is equal to the area under a receiver operating characteristic curve…
Ciardulli, Andrea; D'Antonio, Francesco; Magro-Malosso, Elena R; Manzoli, Lamberto; Anisman, Paul; Saccone, Gabriele; Berghella, Vincenzo
2018-03-07
To explore the effect of maternal fluorinated steroid therapy on fetuses affected by second-degree immune-mediated congenital atrioventricular block. Studies reporting the outcome of fetuses with second-degree immune-mediated congenital atrioventricular block diagnosed on prenatal ultrasound and treated with fluorinated steroids compared with those not treated were included. The primary outcome was the overall progression of congenital atrioventricular block to either continuous or intermittent third-degree congenital atrioventricular block at birth. Meta-analyses of proportions using random effect model and meta-analyses using individual data random-effect logistic regression were used. Five studies (71 fetuses) were included. The progression rate to congenital atrioventricular block at birth in fetuses treated with steroids was 52% (95% confidence interval 23-79) and in fetuses not receiving steroid therapy 73% (95% confidence interval 39-94). The overall rate of regression to either first-degree, intermittent first-/second-degree or sinus rhythm in fetuses treated with steroids was 25% (95% confidence interval 12-41) compared with 23% (95% confidence interval 8-44) in those not treated. Stable (constant) second-degree congenital atrioventricular block at birth was present in 11% (95% confidence interval 2-27) of cases in the treated group and in none of the newborns in the untreated group, whereas complete regression to sinus rhythm occurred in 21% (95% confidence interval 6-42) of fetuses receiving steroids vs. 9% (95% confidence interval 0-41) of those untreated. There is still limited evidence as to the benefit of administered fluorinated steroids in terms of affecting outcome of fetuses with second-degree immune-mediated congenital atrioventricular block. © 2018 Nordic Federation of Societies of Obstetrics and Gynecology.
Validity of self-reported history of Chlamydia trachomatis infection.
Frisse, Ann C; Marrazzo, Jeanne M; Tutlam, Nhial T; Schreiber, Courtney A; Teal, Stephanie B; Turok, David K; Peipert, Jeffrey F
2017-04-01
Chlamydia trachomatis infection is common and largely asymptomatic in women. If untreated, it can lead to sequelae such as pelvic inflammatory disease and infertility. It is unknown whether a patient's self-reported history of Chlamydia trachomatis infection is a valid marker of past infection. Our objective was to evaluate the validity of women's self-reported history of Chlamydia trachomatis infection compared with Chlamydia trachomatis serology, a marker for previous infection. We analyzed data from the Fertility After Contraception Termination study. We compared participants' survey responses with the question, "Have you ever been told by a health care provider that you had Chlamydia?" to serological test results indicating the presence or absence of antibodies to Chlamydia trachomatis as assessed by a microimmunofluorescence assay. Prevalence of past infection, sensitivity, specificity, predictive values, and likelihood ratios were calculated. The Cohen's kappa statistic was computed to assess agreement between self-report and serology. Among 409 participants, 108 (26%) reported having a history of Chlamydia trachomatis infection, whereas 146 (36%) had positive serological test results. Relative to positive microimmunofluorescence assay, the sensitivity and specificity of self-reported history of Chlamydia trachomatis infection were 52.1% (95% confidence interval, 43.6-60.4%) and 87.8% (95% confidence interval, 83.3-91.5%), respectively. The positive predictive value of the self-report was 70.4% (95% confidence interval, 60.8-78.8%), and the negative predictive value was 76.7% (95% confidence interval, 71.6-81.4%). The likelihood ratio was found to be 4.28. Agreement between self-report and serology was found to be moderate (kappa = 0.42, P < .001). Self-reported history of Chlamydia trachomatis infection commonly yields false-negative and false-positive results. When definitive status of past Chlamydia trachomatis infection is needed, serology should be obtained. Copyright © 2016 Elsevier Inc. All rights reserved.
Gaskin, Cadeyrn J; Happell, Brenda
2014-05-01
To (a) assess the statistical power of nursing research to detect small, medium, and large effect sizes; (b) estimate the experiment-wise Type I error rate in these studies; and (c) assess the extent to which (i) a priori power analyses, (ii) effect sizes (and interpretations thereof), and (iii) confidence intervals were reported. Statistical review. Papers published in the 2011 volumes of the 10 highest ranked nursing journals, based on their 5-year impact factors. Papers were assessed for statistical power, control of experiment-wise Type I error, reporting of a priori power analyses, reporting and interpretation of effect sizes, and reporting of confidence intervals. The analyses were based on 333 papers, from which 10,337 inferential statistics were identified. The median power to detect small, medium, and large effect sizes was .40 (interquartile range [IQR]=.24-.71), .98 (IQR=.85-1.00), and 1.00 (IQR=1.00-1.00), respectively. The median experiment-wise Type I error rate was .54 (IQR=.26-.80). A priori power analyses were reported in 28% of papers. Effect sizes were routinely reported for Spearman's rank correlations (100% of papers in which this test was used), Poisson regressions (100%), odds ratios (100%), Kendall's tau correlations (100%), Pearson's correlations (99%), logistic regressions (98%), structural equation modelling/confirmatory factor analyses/path analyses (97%), and linear regressions (83%), but were reported less often for two-proportion z tests (50%), analyses of variance/analyses of covariance/multivariate analyses of variance (18%), t tests (8%), Wilcoxon's tests (8%), Chi-squared tests (8%), and Fisher's exact tests (7%), and not reported for sign tests, Friedman's tests, McNemar's tests, multi-level models, and Kruskal-Wallis tests. Effect sizes were infrequently interpreted. Confidence intervals were reported in 28% of papers. The use, reporting, and interpretation of inferential statistics in nursing research need substantial improvement. Most importantly, researchers should abandon the misleading practice of interpreting the results from inferential tests based solely on whether they are statistically significant (or not) and, instead, focus on reporting and interpreting effect sizes, confidence intervals, and significance levels. Nursing researchers also need to conduct and report a priori power analyses, and to address the issue of Type I experiment-wise error inflation in their studies. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.
Hermans, P G; Morgan, K L
2007-02-01
In order to determine the prevalence and risk factors for necrotic enteritis in broilers, a cross-sectional survey was conducted among 857 farms, rearing broilers for nine UK poultry companies. The main data collection tool was a postal questionnaire directed at farm managers. Additional information on disease occurrence on the farm was collected from veterinary postmortem reports. The response rate to the questionnaire was 75%, ranging from 54% to 90% within companies. During 2001, 32.8% of the respondents indicated that they had observed a case of necrotic enteritis (95% confidence interval, 29.1 to 36.8) in at least one flock. The disease was most often reported during the months October to February. The point prevalence (necrotic enteritis occurrence in the most recently reared flock) reported by farm managers was 12.3% (95% confidence interval, 9.8 to 15.2). Multilevel logistic regression was performed with the poultry company as the random effect, using the occurrence of necrotic enteritis in the farm's most recently reared flock as the dependent variable. Strong associations were found between the outcome variable and the occurrence of wet litter (odds ratio, 2.39; 95% confidence interval, 1.27 to 4.52; P = 0.007) and coccidiosis (odds ratio, 4.68; 95% confidence interval, 1.74 to 12.55; P = 0.002). In addition, the use of ammonia as a disinfectant for coccidial oocysts appeared to be an independent risk factor (odds ratio, 3.44; 95% confidence interval, 1.53 to 7.71; P = 0.003). Finally, the positive association between the use of plasterboard walls in poultry houses and the occurrence of necrotic enteritis might point to an important role of cleaning and disinfection in the epidemiology of this disease (odds ratio, 3.72; 1.38 to 10.00; P = 0.009).
Factors associated with reporting results for pulmonary clinical trials in ClinicalTrials.gov.
Riley, Isaretta L; Boulware, L Ebony; Sun, Jie-Lena; Chiswell, Karen; Que, Loretta G; Kraft, Monica; Todd, Jamie L; Palmer, Scott M; Anderson, Monique L
2018-02-01
Background/aims The Food and Drug Administration Amendments Act mandates that applicable clinical trials report basic summary results to the ClinicalTrials.gov database within 1 year of trial completion or termination. We aimed to determine the proportion of pulmonary trials reporting basic summary results to ClinicalTrials.gov and assess factors associated with reporting. Methods We identified pulmonary clinical trials subject to the Food and Drug Administration Amendments Act (called highly likely applicable clinical trials) that were completed or terminated between 2008 and 2012 and reported results by September 2013. We estimated the cumulative percentage of applicable clinical trials reporting results by pulmonary disease category. Multivariable Cox regression modeling identified characteristics independently associated with results reporting. Results Of 1450 pulmonary highly likely applicable clinical trials, 380 (26%) examined respiratory neoplasms, 238 (16%) asthma, 175 (12%) chronic obstructive pulmonary disease, and 657 (45%) other respiratory diseases. Most (75%) were pharmaceutical highly likely applicable clinical trials and 71% were industry-funded. Approximately 15% of highly likely applicable clinical trials reported results within 1 year of trial completion, while 55% reported results over the 5-year study period. Earlier phase highly likely applicable clinical trials were less likely to report results compared to phase 4 highly likely applicable clinical trials (phases 1/2 and 2 (adjusted hazard ratio 0.41 (95% confidence interval: 0.31-0.54)), phases 2/3 and 3 (adjusted hazard ratio 0.55 (95% confidence interval: 0.42-0.72)) and phase not applicable (adjusted hazard ratio 0.43 (95% confidence interval: 0.29-0.63)). Pulmonary highly likely applicable clinical trials without Food and Drug Administration oversight were less likely to report results compared with those with oversight (adjusted hazard ratio 0.65 (95% confidence interval: 0.51-0.83)). Conclusion A total of 15% of pulmonary clinical highly likely applicable clinical trials report basic summary results to ClinicalTrials.gov within 1 year of trial completion. Strategies to improve reporting are needed within the pulmonary community.
ERIC Educational Resources Information Center
Du, Yunfei
This paper discusses the impact of sampling error on the construction of confidence intervals around effect sizes. Sampling error affects the location and precision of confidence intervals. Meta-analytic resampling demonstrates that confidence intervals can haphazardly bounce around the true population parameter. Special software with graphical…
On Some Confidence Intervals for Estimating the Mean of a Skewed Population
ERIC Educational Resources Information Center
Shi, W.; Kibria, B. M. Golam
2007-01-01
A number of methods are available in the literature to measure confidence intervals. Here, confidence intervals for estimating the population mean of a skewed distribution are considered. This note proposes two alternative confidence intervals, namely, Median t and Mad t, which are simple adjustments to the Student's t confidence interval. In…
2014-01-01
Background Thresholds for statistical significance are insufficiently demonstrated by 95% confidence intervals or P-values when assessing results from randomised clinical trials. First, a P-value only shows the probability of getting a result assuming that the null hypothesis is true and does not reflect the probability of getting a result assuming an alternative hypothesis to the null hypothesis is true. Second, a confidence interval or a P-value showing significance may be caused by multiplicity. Third, statistical significance does not necessarily result in clinical significance. Therefore, assessment of intervention effects in randomised clinical trials deserves more rigour in order to become more valid. Methods Several methodologies for assessing the statistical and clinical significance of intervention effects in randomised clinical trials were considered. Balancing simplicity and comprehensiveness, a simple five-step procedure was developed. Results For a more valid assessment of results from a randomised clinical trial we propose the following five-steps: (1) report the confidence intervals and the exact P-values; (2) report Bayes factor for the primary outcome, being the ratio of the probability that a given trial result is compatible with a ‘null’ effect (corresponding to the P-value) divided by the probability that the trial result is compatible with the intervention effect hypothesised in the sample size calculation; (3) adjust the confidence intervals and the statistical significance threshold if the trial is stopped early or if interim analyses have been conducted; (4) adjust the confidence intervals and the P-values for multiplicity due to number of outcome comparisons; and (5) assess clinical significance of the trial results. Conclusions If the proposed five-step procedure is followed, this may increase the validity of assessments of intervention effects in randomised clinical trials. PMID:24588900
Tominaga, K; Andow, J; Koyama, Y; Numao, S; Kurokawa, E; Ojima, M; Nagai, M
1998-01-01
Many psychosocial factors have been reported to influence the duration of survival of breast cancer patients. We have studied how family members, hobbies and habits of the patients may alter their psychosocial status. Female patients with surgically treated breast cancer diagnosed between 1986 and 1995 at the Tochigi Cancer Center Hospital, who provided information on the above-mentioned factors, were used. Their subsequent physical status was followed up in the outpatients clinic. The Cox regression model was used to evaluate the relationship between the results of the factors examined and the duration of the patients' survival, adjusting for the patients' age, stage of disease at diagnosis and curability, as judged by the physician in charge after the treatment. The following factors were revealed to be significant with regard to the survival of surgically treated breast cancer patients: being a widow (hazard ratio 3.29; 95% confidence interval 1.32-8.20), having a hobby (hazard ratio 0.43; 95% confidence interval 0.23-0.82), number of hobbies (hazard ratio 0.64; 95% confidence interval 0.41-1.00), number of female children (hazard ratio 0.64; 95% confidence interval 0.42-0.98), smoker (hazard ratio 2.08; 95% confidence interval 1.02-4.26) and alcohol consumption (hazard ratio 0.10; 95% confidence interval 0.01-0.72). These results suggest that psychosocial factors, including the family environment, where patients receive emotional support from their spouse and children, hobbies and the patients' habits, may influence the duration of survival in surgically treated breast cancer patients.
Mandell, Jacob C; Weaver, Michael J; Khurana, Bharti
2018-06-01
The purpose of this study was to evaluate the diagnostic performance of CT for assessment of occult fractures of the proximal femur, pelvis, and sacrum. A retrospective review was performed on patients who received a CT of the hip or pelvis for suspected occult fracture after negative or equivocal radiographs performed within 24 h. The official radiology report was utilized for the determination of CT findings and calculation of sensitivity and specificity. Surgical reports, MRI reports, and clinical follow-up were used as the standard of reference. Sensitivity and specificity were calculated with 95% confidence intervals. Seventy-four patients received CT of the hip or pelvis for clinical concern for occult fracture after negative or equivocal radiographs. By the reference standard, a total of 40 fractures were present in 25/74 (33.8%) patients, including 35 conservatively treated fractures of the greater trochanter, pelvis, and sacrum, and 5 operatively treated proximal femoral fractures. A total of 14/74 (18.9%) of patients had an MRI within 1 day of CT. MRI identified an operatively treated femoral neck fracture not seen on CT and an operatively treated intertrochanteric fracture, which CT described as a greater trochanteric fracture. There were two false negative conservatively treated pelvic fractures not seen on CT but diagnosed on MRI. On a per-patient basis, CT had an overall sensitivity of 88% (22/25; 95% confidence intervals 69-97%), specificity of 98% (48/49; 95% confidence intervals 89-100%), and negative predictive value of 94%. For the five operative proximal femoral fractures, the sensitivity of CT was 60% (3/5; 95% confidence intervals 15-95%), specificity was 99% (68/69; 95% confidence intervals 92-100%), and negative predictive value was 97%. In the clinical setting of suspected occult fracture, the sensitivity of clinical CT reports for detection of any type of fracture of the proximal femur, pelvis, or sacrum was 88%. For the small number of operatively treated proximal femoral fractures seen in the study, sensitivity of CT was 60% (3/5) and negative predictive value was 97%, although the relatively few patients needing fixation precludes statistical analysis.
Microcephaly Case Fatality Rate Associated with Zika Virus Infection in Brazil: Current Estimates.
Cunha, Antonio José Ledo Alves da; de Magalhães-Barbosa, Maria Clara; Lima-Setta, Fernanda; Medronho, Roberto de Andrade; Prata-Barbosa, Arnaldo
2017-05-01
Considering the currently confirmed cases of microcephaly and related deaths associated with Zika virus in Brazil, the estimated case fatality rate is 8.3% (95% confidence interval: 7.2-9.6). However, a third of the reported cases remain under investigation. If the confirmation rates of cases and deaths are the same in the future, the estimated case fatality rate will be as high as 10.5% (95% confidence interval: 9.5-11.7).
Financial Hardship and Patient-Reported Outcomes after Hematopoietic Cell Transplantation.
Abel, Gregory A; Albelda, Randy; Khera, Nandita; Hahn, Theresa; Salas Coronado, Diana Y; Odejide, Oreofe O; Bona, Kira; Tucker-Seeley, Reginald; Soiffer, Robert
2016-08-01
Although hematopoietic cell transplantation (HCT) is the only curative therapy for many advanced hematologic cancers, little is known about the financial hardship experienced by HCT patients nor the association of hardship with patient-reported outcomes. We mailed a 43-item survey to adult patients approximately 180 days after their first autologous or allogeneic HCT at 3 high-volume centers. We assessed decreases in household income; difficulty with HCT-related costs, such as need to relocate or travel; and 2 types of hardship: hardship_1 (reporting 1 or 2 of the following: dissatisfaction with present finances, difficulty meeting monthly bill payments, or not having enough money at the end of the month) and "hardship_2" (reporting all 3). Patient-reported stress was measured with the Perceived Stress Scale-4, and 7-point scales were provided for perceptions of overall quality of life (QOL) and health. In total, 325 of 499 surveys (65.1%) were received. The median days since HCT was 173; 47% underwent an allogeneic HCT, 60% were male, 51% were > 60 years old, and 92% were white. Overall, 46% reported income decline after HCT, 56% reported hardship_1, and 15% reported hardship_2. In multivariable models controlling for income, those reporting difficulty paying for HCT-related costs were more likely to report financial hardship (odds ratio, 6.9; 95% confidence interval, 3.8 to 12.3). Hardship_1 was associated with QOL below the median (odds ratio, 2.9; 95% confidence interval, 1.7 to 4.9), health status below the median (odds ratio, 2.2; 95% confidence interval, 1.3 to 3.6), and stress above the median (odds ratio, 2.1; 95% confidence interval, 1.3 to 3.5). In this sizable cohort of HCT patients, financial hardship was prevalent and associated with worse QOL and higher levels of perceived stress. Interventions to address patient financial hardship-especially those that ameliorate HCT-specific costs-are likely to improve patient-reported outcomes. Copyright © 2016 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.
Amnioinfusion for meconium-stained liquor in labour.
Hofmeyr, G J
2000-01-01
Amnioinfusion aims to prevent or relieve umbilical cord compression during labour by infusing a solution into the uterine cavity. It is also thought to dilute meconium when present in the amniotic fluid and so reduce the risk of meconium aspiration. However it may be that the mechanism of effect is that it corrects oligohydramnios (reduced amniotic fluid), for which thick meconium staining is a marker. The objective of this review was to assess the effects of amnioinfusion for meconium-stained liquor on perinatal outcome. The Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register were searched. Randomised trials comparing amnioinfusion with no amnioinfusion for women in labour with moderate or thick meconium-staining of the amniotic fluid. Eligibility and trial quality were assessed by one reviewer. Ten studies, most involving small numbers of participants, were included. Under standard perinatal surveillance, amnioinfusion was associated with a reduction in the following: heavy meconium staining of the liquor (relative risk 0.03, 95% confidence interval 0.01 to 0.15); variable fetal heart rate deceleration (relative risk 0.47, 95% confidence interval 0.24 to 0. 90); and a trend to reduced caesarean section overall (relative risk 0.83, 95% confidence interval 0.69 to 1.00). No perinatal deaths were reported. Under limited perinatal surveillance, amnioinfusion was associated with a reduction in the following: meconium aspiration syndrome (relative risk 0.24, 95% confidence interval 0. 12 to 0.48); neonatal hypoxic ischaemic encephalopathy (relative risk 0.07, 95% confidence interval 0.01 to 0.56) and neonatal ventilation or intensive care unit admission (relative risk 0.56, 95% confidence interval 0.39 to 0.79); there was a trend towards reduced perinatal mortality (relative risk 0.34, 95% confidence interval 0.11 to 1.06). Amnioinfusion is associated with improvements in perinatal outcome, particularly in settings where facilities for perinatal surveillance are limited. The trials reviewed are too small to address the possibility of rare but serious maternal adverse effects of amnioinfusion.
Amnioinfusion for meconium-stained liquor in labour.
Hofmeyr, G J
2002-01-01
Amnioinfusion aims to prevent or relieve umbilical cord compression during labour by infusing a solution into the uterine cavity. It is also thought to dilute meconium when present in the amniotic fluid and so reduce the risk of meconium aspiration. However, it may be that the mechanism of effect is that it corrects oligohydramnios (reduced amniotic fluid), for which thick meconium staining is a marker. The objective of this review was to assess the effects of amnioinfusion for meconium-stained liquor on perinatal outcome. The Cochrane Pregnancy and Childbirth Group trials register (October 2001) and the Cochrane Controlled Trials Register (Issue 3, 2001) were searched. Randomised trials comparing amnioinfusion with no amnioinfusion for women in labour with moderate or thick meconium-staining of the amniotic fluid. Eligibility and trial quality were assessed by one reviewer. Twelve studies, most involving small numbers of participants, were included. Under standard perinatal surveillance, amnioinfusion was associated with a reduction in the following: heavy meconium staining of the liquor (relative risk 0.03, 95% confidence interval 0.01 to 0.15); variable fetal heart rate deceleration (relative risk 0.65, 95% confidence interval 0.49 to 0.88); and reduced caesarean section overall (relative risk 0.82, 95% confidence interval 0.69 to 1.97). No perinatal deaths were reported. Under limited perinatal surveillance, amnioinfusion was associated with a reduction in the following: meconium aspiration syndrome (relative risk 0.24, 95% confidence interval 0.12 to 0.48); neonatal hypoxic ischaemic encephalopathy (relative risk 0.07, 95% confidence interval 0.01 to 0.56) and neonatal ventilation or intensive care unit admission (relative risk 0.56, 95% confidence interval 0.39 to 0.79); there was a trend towards reduced perinatal mortality (relative risk 0.34, 95% confidence interval 0.11 to 1.06). Amnioinfusion is associated with improvements in perinatal outcome, particularly in settings where facilities for perinatal surveillance are limited. The trials reviewed are too small to address the possibility of rare but serious maternal adverse effects of amnioinfusion.
Lam, Lai Wah; Twinn, Sheila F; Chan, Sally W C
2010-04-01
This paper is a report of a study conducted to examine self-reported adherence to a therapeutic regimen for continuous ambulatory peritoneal dialysis. Studies of patients' adherence during dialysis have primarily focused on haemodialysis and have frequently yielded inconsistent results, which are attributed to the inconsistent tools used to measure adherence. Levels of adherence to all four components of the therapeutic regimen (i.e. dietary and fluid restrictions, medication, and the dialysis regimen) among patients receiving peritoneal dialysis have not been examined, especially from a patient perspective. A total population sample was used. A cross-sectional survey was carried out by face-to-face interviews in 2005 in one renal clinic in Hong Kong. A total of 173 patients undergoing peritoneal dialysis (56% of the total population) participated in the study. Patients perceived themselves as more adherent to medication (83%; 95% confidence interval 77-88%) and dialysis (93%; 95% confidence interval 88-96%) prescriptions than to fluid (64%; 95% confidence interval 56-71%) and dietary (38%; 95% confidence interval 30-45%) restrictions. Those who were male, younger or had received dialysis for 1-3 years saw themselves as more non-adherent compared with other patients. Healthcare professionals should take cultural issues into consideration when setting dietary and fluid restriction guidelines. Additional attention and support are required for patients who identify themselves as more non-adherent. To help patients live with end-stage renal disease and its treatment, qualitative research is required to understand how they go through the dynamic process of adherence.
Ramji, Rathi; Arnetz, Judy; Nilsson, Maria; Jamil, Hikmet; Norström, Fredrik; Maziak, Wasim; Wiklund, Ywonne; Arnetz, Bengt
2015-09-15
Determinants of waterpipe use in adolescents are believed to differ from those for other tobacco products, but there is a lack of studies of possible social, cultural, or psychological aspects of waterpipe use in this population. This study applied a socioecological model to explore waterpipe use, and its relationship to other tobacco use in Swedish adolescents. A total of 106 adolescents who attended an urban high-school in northern Sweden responded to an anonymous questionnaire. Prevalence rates for waterpipe use were examined in relation to socio-demographics, peer pressure, sensation seeking behavior, harm perception, environmental factors, and depression. Thirty-three percent reported ever having smoked waterpipe (ever use), with 30% having done so during the last 30 days (current use). Among waterpipe ever users, 60% had ever smoked cigarettes in comparison to 32% of non-waterpipe smokers (95% confidence interval 1.4-7.9). The odds of having ever smoked waterpipe were three times higher among male high school seniors as well as students with lower grades. Waterpipe ever users had three times higher odds of having higher levels of sensation-seeking (95% confidence interval 1.2-9.5) and scored high on the depression scales (95% confidence interval 1.6-6.8) than non-users. The odds of waterpipe ever use were four times higher for those who perceived waterpipe products to have pleasant smell compared to cigarettes (95% confidence interval 1.7-9.8). Waterpipe ever users were twice as likely to have seen waterpipe use on television compared to non-users (95% confidence interval 1.1-5.7). The odds of having friends who smoked regularly was eight times higher for waterpipe ever users than non-users (95% confidence interval 2.1-31.2). The current study reports a high use of waterpipe in a select group of students in northern Sweden. The study adds the importance of looking at socioecological determinants of use, including peer pressure and exposure to media marketing, as well as mental health among users.
Diesel exhaust, diesel fumes, and laryngeal cancer.
Muscat, J E; Wynder, E L
1995-03-01
A hospital-based, case-control study of 235 male patients with laryngeal cancer and 205 male control patients was conducted to determine the effects of exposure to diesel engine exhaust and diesel fumes and the risk of laryngeal cancer. All patients were interviewed directly in the hospital with a standardized questionnaire that gathered information on smoking habits, alcohol consumption, employment history, and occupational exposures. Occupations that involve substantial exposure to diesel engine exhaust include mainly truck drivers, as well as mine workers, firefighters, and railroad workers. The odds ratio for laryngeal cancer associated with these occupations was 0.96 (95% confidence interval, 0.5 to 1.8). The odds ratio for self-reported exposure to diesel exhaust was 1.47 (95% confidence interval, 0.5 to 4.1). An elevated risk was found for self-reported exposure to diesel fumes (odds ratio, 6.4; 95% confidence interval, 1.8 to 22.6). No association was observed between jobs that entail exposure to diesel fumes, such as automobile mechanics, and the risk of laryngeal cancer. These results show that diesel engine exhaust is unrelated to laryngeal cancer risk. The different findings for self-reported diesel fumes and occupations that involve exposure to diesel fumes could reflect a recall bias.
Magro-Malosso, Elena Rita; Saccone, Gabriele; Di Tommaso, Mariarosaria; Mele, Michele; Berghella, Vincenzo
2016-09-01
External cephalic version is a medical procedure in which the fetus is externally manipulated to assume the cephalic presentation. The use of neuraxial analgesia for facilitating the version has been evaluated in several randomized clinical trials, but its potential effects are still controversial. The objective of the study was to evaluate the effectiveness of neuraxial analgesia as an intervention to increase the success rate of external cephalic version. Searches were performed in electronic databases with the use of a combination of text words related to external cephalic version and neuraxial analgesia from the inception of each database to January 2016. We included all randomized clinical trials of women, with a gestational age ≥36 weeks and breech or transverse fetal presentation, undergoing external cephalic version who were randomized to neuraxial analgesia, including spinal, epidural, or combined spinal-epidural techniques (ie, intervention group) or to a control group (either intravenous analgesia or no treatment). The primary outcome was the successful external cephalic version. The summary measures were reported as relative risk or as mean differences with a 95% confidence interval. Nine randomized clinical trials (934 women) were included in this review. Women who received neuraxial analgesia had a significantly higher incidence of successful external cephalic version (58.4% vs 43.1%; relative risk, 1.44, 95% confidence interval, 1.27-1.64), cephalic presentation in labor (55.1% vs 40.2%; relative risk, 1.37, 95% confidence interval, 1.08-1.73), and vaginal delivery (54.0% vs 44.6%; relative risk, 1.21, 95% confidence interval, 1.04-1.41) compared with those who did not. Women who were randomized to the intervention group also had a significantly lower incidence of cesarean delivery (46.0% vs 55.3%; relative risk, 0.83, 95% confidence interval, 0.71-0.97), maternal discomfort (1.2% vs 9.3%; relative risk, 0.12, 95% confidence interval, 0.02-0.99), and lower pain, assessed by the visual analog scale pain score (mean difference, -4.52 points, 95% confidence interval, -5.35 to 3.69) compared with the control group. The incidences of emergency cesarean delivery (1.6% vs 2.5%; relative risk, 0.63, 95% confidence interval, 0.24-1.70), transient bradycardia (11.8% vs 8.3%; relative risk, 1.42, 95% confidence interval, 0.72-2.80), nonreassuring fetal testing, excluding transient bradycardia, after external cephalic version (6.9% vs 7.4%; relative risk, 0.93, 95% confidence interval, 0.53-1.64), and abruption placentae (0.4% vs 0.4%; relative risk, 1.01, 95% confidence interval, 0.06-16.1) were similar. Administration of neuraxial analgesia significantly increases the success rate of external cephalic version among women with malpresentation at term or late preterm, which then significantly increases the incidence of vaginal delivery. Copyright © 2016 Elsevier Inc. All rights reserved.
O'Gorman, Thomas W
2018-05-01
In the last decade, it has been shown that an adaptive testing method could be used, along with the Robbins-Monro search procedure, to obtain confidence intervals that are often narrower than traditional confidence intervals. However, these confidence interval limits require a great deal of computation and some familiarity with stochastic search methods. We propose a method for estimating the limits of confidence intervals that uses only a few tests of significance. We compare these limits to those obtained by a lengthy Robbins-Monro stochastic search and find that the proposed method is nearly as accurate as the Robbins-Monro search. Adaptive confidence intervals that are produced by the proposed method are often narrower than traditional confidence intervals when the distributions are long-tailed, skewed, or bimodal. Moreover, the proposed method of estimating confidence interval limits is easy to understand, because it is based solely on the p-values from a few tests of significance.
Naganuma, Misa; Motooka, Yumi; Sasaoka, Sayaka; Hatahira, Haruna; Hasegawa, Shiori; Fukuda, Akiho; Nakao, Satoshi; Shimada, Kazuyo; Hirade, Koseki; Mori, Takayuki; Yoshimura, Tomoaki; Kato, Takeshi; Nakamura, Mitsuhiro
2018-01-01
Platinum compounds cause several adverse events, such as nephrotoxicity, gastrointestinal toxicity, myelosuppression, ototoxicity, and neurotoxicity. We evaluated the incidence of renal impairment as adverse events are related to the administration of platinum compounds using the Japanese Adverse Drug Event Report database. We analyzed adverse events associated with the use of platinum compounds reported from April 2004 to November 2016. The reporting odds ratio at 95% confidence interval was used to detect the signal for each renal impairment incidence. We evaluated the time-to-onset profile of renal impairment and assessed the hazard type using Weibull shape parameter and used the applied association rule mining technique to discover undetected relationships such as possible risk factor. In total, 430,587 reports in the Japanese Adverse Drug Event Report database were analyzed. The reporting odds ratios (95% confidence interval) for renal impairment resulting from the use of cisplatin, oxaliplatin, carboplatin, and nedaplatin were 2.7 (2.5-3.0), 0.6 (0.5-0.7), 0.8 (0.7-1.0), and 1.3 (0.8-2.1), respectively. The lower limit of the reporting odds ratio (95% confidence interval) for cisplatin was >1. The median (lower-upper quartile) onset time of renal impairment following the use of platinum-based compounds was 6.0-8.0 days. The Weibull shape parameter β and 95% confidence interval upper limit of oxaliplatin were <1. In the association rule mining, the score of lift for patients who were treated with cisplatin and co-administered furosemide, loxoprofen, or pemetrexed was high. Similarly, the scores for patients with hypertension or diabetes mellitus were high. Our findings suggest a potential risk of renal impairment during cisplatin use in real-world setting. The present findings demonstrate that the incidence of renal impairment following cisplatin use should be closely monitored when patients are hypertensive or diabetic, or when they are co-administered furosemide, loxoprofen, or pemetrexed. In addition, healthcare professionals should closely assess a patient's background prior to treatment.
2014-01-01
Background Meta-regression is becoming increasingly used to model study level covariate effects. However this type of statistical analysis presents many difficulties and challenges. Here two methods for calculating confidence intervals for the magnitude of the residual between-study variance in random effects meta-regression models are developed. A further suggestion for calculating credible intervals using informative prior distributions for the residual between-study variance is presented. Methods Two recently proposed and, under the assumptions of the random effects model, exact methods for constructing confidence intervals for the between-study variance in random effects meta-analyses are extended to the meta-regression setting. The use of Generalised Cochran heterogeneity statistics is extended to the meta-regression setting and a Newton-Raphson procedure is developed to implement the Q profile method for meta-analysis and meta-regression. WinBUGS is used to implement informative priors for the residual between-study variance in the context of Bayesian meta-regressions. Results Results are obtained for two contrasting examples, where the first example involves a binary covariate and the second involves a continuous covariate. Intervals for the residual between-study variance are wide for both examples. Conclusions Statistical methods, and R computer software, are available to compute exact confidence intervals for the residual between-study variance under the random effects model for meta-regression. These frequentist methods are almost as easily implemented as their established counterparts for meta-analysis. Bayesian meta-regressions are also easily performed by analysts who are comfortable using WinBUGS. Estimates of the residual between-study variance in random effects meta-regressions should be routinely reported and accompanied by some measure of their uncertainty. Confidence and/or credible intervals are well-suited to this purpose. PMID:25196829
Faggion, Clovis Mariano; Aranda, Luisiana; Diaz, Karla Tatiana; Shih, Ming-Chieh; Tu, Yu-Kang; Alarcón, Marco Antonio
2016-01-01
Information on precision of treatment-effect estimates is pivotal for understanding research findings. In animal experiments, which provide important information for supporting clinical trials in implant dentistry, inaccurate information may lead to biased clinical trials. The aim of this methodological study was to determine whether sample size calculation, standard errors, and confidence intervals for treatment-effect estimates are reported accurately in publications describing animal experiments in implant dentistry. MEDLINE (via PubMed), Scopus, and SciELO databases were searched to identify reports involving animal experiments with dental implants published from September 2010 to March 2015. Data from publications were extracted into a standardized form with nine items related to precision of treatment estimates and experiment characteristics. Data selection and extraction were performed independently and in duplicate, with disagreements resolved by discussion-based consensus. The chi-square and Fisher exact tests were used to assess differences in reporting according to study sponsorship type and impact factor of the journal of publication. The sample comprised reports of 161 animal experiments. Sample size calculation was reported in five (2%) publications. P values and confidence intervals were reported in 152 (94%) and 13 (8%) of these publications, respectively. Standard errors were reported in 19 (12%) publications. Confidence intervals were better reported in publications describing industry-supported animal experiments (P = .03) and with a higher impact factor (P = .02). Information on precision of estimates is rarely reported in publications describing animal experiments in implant dentistry. This lack of information makes it difficult to evaluate whether the translation of animal research findings to clinical trials is adequate.
Empirical likelihood-based confidence intervals for mean medical cost with censored data.
Jeyarajah, Jenny; Qin, Gengsheng
2017-11-10
In this paper, we propose empirical likelihood methods based on influence function and jackknife techniques for constructing confidence intervals for mean medical cost with censored data. We conduct a simulation study to compare the coverage probabilities and interval lengths of our proposed confidence intervals with that of the existing normal approximation-based confidence intervals and bootstrap confidence intervals. The proposed methods have better finite-sample performances than existing methods. Finally, we illustrate our proposed methods with a relevant example. Copyright © 2017 John Wiley & Sons, Ltd.
Ishida, Hidekazu; Kawazu, Yukiko; Kayatani, Futoshi; Inamura, Noboru
2017-05-01
A number of case reports show various outcomes of premature closure of the ductus arteriosus in utero, including persistent pulmonary hypertension of the newborn and fetal or neonatal death; however, no study clarifies the clinical observations that are related to their prognoses. We aimed to clarify the prognostic factors of intrauterine ductal closure by a systematic literature review. Data sources We searched PubMed database (1975-2014) to identify case reports and studies on intrauterine closure of the ductus arteriosus, including maternal, fetal, and neonatal clinical information and their prognoses. We analysed the data of 116 patients from 39 articles. Of these, 12 (10.3%) died after birth or in utero. Fetal or neonatal death was significantly correlated with fetal hydrops (odds ratio=39.6, 95% confidence interval=4.6-47.8) and complete closure of the ductus arteriosus (odds ratio=5.5, 95% confidence interval=1.2-15.1). Persistent pulmonary hypertension was observed in 33 cases (28.4%), and was also correlated with fetal hydrops (odds ratio=4.2, 95% confidence interval=1.3-4.6) and complete closure of the ductus arteriosus (odds ratio=5.5, 95% confidence interval=1.6-6.0). Interestingly, maternal drug administration was not correlated with the risk of death and persistent pulmonary hypertension. Fetal hydrops and complete ductal closure are significant risk factors for both death and persistent pulmonary hypertension. Cardiac or neurological prognoses could be favourable if the patients overcome right heart failure during the perinatal period.
McGovern, Aine; Pendlebury, Sarah T; Mishra, Nishant K; Fan, Yuhua; Quinn, Terence J
2016-02-01
Poststroke cognitive assessment can be performed using standardized questionnaires designed for family or care givers. We sought to describe the test accuracy of such informant-based assessments for diagnosis of dementia/multidomain cognitive impairment in stroke. We performed a systematic review using a sensitive search strategy across multidisciplinary electronic databases. We created summary test accuracy metrics and described reporting and quality using STARDdem and Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tools, respectively. From 1432 titles, we included 11 studies. Ten papers used the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). Four studies described IQCODE for diagnosis of poststroke dementia (n=1197); summary sensitivity: 0.81 (95% confidence interval, 0.60-0.93); summary specificty: 0.83 (95% confidence interval, 0.64-0.93). Five studies described IQCODE as tool for predicting future dementia (n=837); summary sensitivity: 0.60 (95% confidence interval, 0.32-0.83); summary specificity: 0.97 (95% confidence interval, 0.70-1.00). All papers had issues with at least 1 aspect of study reporting or quality. There is a limited literature on informant cognitive assessments in stroke. IQCODE as a diagnostic tool has test properties similar to other screening tools, IQCODE as a prognostic tool is specific but insensitive. We found no papers describing test accuracy of informant tests for diagnosis of prestroke cognitive decline, few papers on poststroke dementia and all included papers had issues with potential bias. © 2015 American Heart Association, Inc.
Al-Ali, Amein; Alkhawajah, Abdul Aziz; Randhawa, Mohammad Akram; Shaikh, Nisar Ahmed
2008-01-01
Thymoquinone is the major active principle of Nigella sativa (N. sativa) and constitutes about 30% of its volatile oil or ether extract. N. sativa oil and seed are commonly used as a natural remedy for many ailments. Using modern scientific techniques, a number of pharmacological actions of N. sativa have been investigated including immunostimulant, anti-inflammatory, anticancer, antioxidant, antihistaminic, antiasthmatic, hypoglycemic, antimicrobial and antiparasitic. There are only few reports regarding the toxicity of thymoquinone. The present study was carried out to determine LD50 of thymoquinone both in mice and rats, orally as well as intraperitoneall, by the method of Miller and Tainter. Autopsy and histopathology of liver, kidney, heart and lungs were also determined. The LD50 in mice after intraperitoneal injection was determined to be 104.7 mg/kg (89.7-119.7, 95% confidence interval) and after oral ingestion was 870.9 mg/kg (647.1-1094.8, 95% confidence interval). Whereas, LD50 in rats after intraperitoneal injection was determined to be 57.5 mg/kg (45.6-69.4, 95% confidence intervals) and after oral ingestion was 794.3 mg/kg (469.8-1118.8, 95% confidence intervals). The LD50 values presented here after intraperitoneal injection and oral gavages are 10-15 times and 100-150 times greater than doses of thymoquinone reported for its anti-inflammatory, anti-oxidant and anti-cancer effects. Thymoquinone is a relatively safe compound, particularly when given orally to experimental animals.
Rosenblum, Michael A; Laan, Mark J van der
2009-01-07
The validity of standard confidence intervals constructed in survey sampling is based on the central limit theorem. For small sample sizes, the central limit theorem may give a poor approximation, resulting in confidence intervals that are misleading. We discuss this issue and propose methods for constructing confidence intervals for the population mean tailored to small sample sizes. We present a simple approach for constructing confidence intervals for the population mean based on tail bounds for the sample mean that are correct for all sample sizes. Bernstein's inequality provides one such tail bound. The resulting confidence intervals have guaranteed coverage probability under much weaker assumptions than are required for standard methods. A drawback of this approach, as we show, is that these confidence intervals are often quite wide. In response to this, we present a method for constructing much narrower confidence intervals, which are better suited for practical applications, and that are still more robust than confidence intervals based on standard methods, when dealing with small sample sizes. We show how to extend our approaches to much more general estimation problems than estimating the sample mean. We describe how these methods can be used to obtain more reliable confidence intervals in survey sampling. As a concrete example, we construct confidence intervals using our methods for the number of violent deaths between March 2003 and July 2006 in Iraq, based on data from the study "Mortality after the 2003 invasion of Iraq: A cross sectional cluster sample survey," by Burnham et al. (2006).
ERIC Educational Resources Information Center
Weber, Deborah A.
Greater understanding and use of confidence intervals is central to changes in statistical practice (G. Cumming and S. Finch, 2001). Reliability coefficients and confidence intervals for reliability coefficients can be computed using a variety of methods. Estimating confidence intervals includes both central and noncentral distribution approaches.…
Williamson, Wilby; Foster, Charlie; Reid, Hamish; Kelly, Paul; Lewandowski, Adam James; Boardman, Henry; Roberts, Nia; McCartney, David; Huckstep, Odaro; Newton, Julia; Dawes, Helen; Gerry, Stephen; Leeson, Paul
2016-07-01
Previous studies report benefits of exercise for blood pressure control in middle age and older adults, but longer-term effectiveness in younger adults is not well established. We performed a systematic review and meta-analysis of published randomized control trials with meta-regression of potential effect modifiers. An information specialist completed a comprehensive search of available data sources, including studies published up to June 2015. Authors applied strict inclusion and exclusion criteria to screen 9524 titles. Eligible studies recruited younger adults with a cardiovascular risk factor (with at least 25% of cohort aged 18-40 years); the intervention had a defined physical activity strategy and reported blood pressure as primary or secondary outcome. Meta-analysis included 14 studies randomizing 3614 participants, mean age 42.2±6.3 (SD) years. At 3 to 6 months, exercise was associated with a reduction in systolic blood pressure of -4.40 mm Hg (95% confidence interval, -5.78 to -3.01) and in diastolic blood pressure of -4.17 mm Hg (95% confidence interval, -5.42 to -2.93). Intervention effect was not significantly influenced by baseline blood pressure, body weight, or subsequent weight loss. Observed intervention effect was lost after 12 months of follow-up with no reported benefit over control, mean difference in systolic blood pressure -1.02 mm Hg (95% confidence interval, -2.34 to 0.29), and in diastolic blood pressure -0.91 mm Hg (95% confidence interval, -1.85 to 0.02). Current exercise guidance provided to reduce blood pressure in younger adults is unlikely to benefit long-term cardiovascular risk. There is need for continued research to improve age-specific strategies and recommendations for hypertension prevention and management in young adults. © 2016 The Authors.
Barker-Collo, Suzanne; Krishnamurthi, Rita; Witt, Emma; Feigin, Valery; Jones, Amy; McPherson, Kathryn; Starkey, Nicola; Parag, Varsha; Jiang, Yannan; Barber, P Alan; Rush, Elaine; Bennett, Derrick; Aroll, Bruce
2015-12-01
Stroke recurrence rates are high (20%-25%) and have not declined over past 3 decades. This study tested effectiveness of motivational interviewing (MI) for reducing stroke recurrence, measured by improving adherence to recommended medication and lifestyle changes compared with usual care. Single-blind, prospective phase III randomized controlled trial of 386 people with stroke assigned to either MI treatment (4 sessions at 28 days, 3, 6, and 9 months post stroke) or usual care; with outcomes assessed at 28 days, 3, 6, 9, and 12 months post stroke. Primary outcomes were change in systolic blood pressure and low-density lipoprotein cholesterol levels as indicators of adherence at 12 months. Secondary outcomes included self-reported adherence, new stroke, or coronary heart disease events (both fatal and nonfatal); quality of life (Short Form-36); and mood (Hospital Anxiety and Depression Scale). MI did not significantly change measures of blood pressure (mean difference in change, -0.2.35 [95% confidence interval, -6.16 to 1.47]) or cholesterol (mean difference in change, -0.0.12 [95% confidence interval, -0.30 to 0.06]). However, it had positive effects on self-reported medication adherence at 6 months (1.979; 95% confidence interval, 0.98-3.98; P=0.0557) and 9 months (4.295; 95% confidence interval, 1.56-11.84; P=0.0049) post stroke. Improvement across other measures was also observed, but the differences between MI and usual care groups were not statistically significant. MI improved self-reported medication adherence. All other effects were nonsignificant, though in the direction of a treatment effect. Further study is required to determine whether MI leads to improvement in other important areas of functioning (eg, caregiver burden). URL: http://www.anzctr.org.au. Unique identifier: ACTRN-12610000715077. © 2015 American Heart Association, Inc.
Guimaraes, Carolina V; Grzeszczuk, Robert; Bisset, George S; Donnelly, Lane F
2018-03-01
When implementing or monitoring department-sanctioned standardized radiology reports, feedback about individual faculty performance has been shown to be a useful driver of faculty compliance. Most commonly, these data are derived from manual audit, which can be both time-consuming and subject to sampling error. The purpose of this study was to evaluate whether a software program using natural language processing and machine learning could accurately audit radiologist compliance with the use of standardized reports compared with performed manual audits. Radiology reports from a 1-month period were loaded into such a software program, and faculty compliance with use of standardized reports was calculated. For that same period, manual audits were performed (25 reports audited for each of 42 faculty members). The mean compliance rates calculated by automated auditing were then compared with the confidence interval of the mean rate by manual audit. The mean compliance rate for use of standardized reports as determined by manual audit was 91.2% with a confidence interval between 89.3% and 92.8%. The mean compliance rate calculated by automated auditing was 92.0%, within that confidence interval. This study shows that by use of natural language processing and machine learning algorithms, an automated analysis can accurately define whether reports are compliant with use of standardized report templates and language, compared with manual audits. This may avoid significant labor costs related to conducting the manual auditing process. Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.
Post-traumatic stress disorder in adolescents after a hurricane.
Garrison, C Z; Weinrich, M W; Hardin, S B; Weinrich, S; Wang, L
1993-10-01
A school-based study conducted in 1990, 1 year after Hurricane Hugo, investigated the frequency and correlates of post-traumatic stress disorder (PTSD) in 1,264 adolescents aged 11-17 years residing in selected South Carolina communities. Data were collected via a 174-item self-administered questionnaire that included a PTSD symptom scale. A computer algorithm that applied decision rules of the Diagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised to the symptoms reported was used to assign a diagnosis of PTSD and to designate the number of individuals who met the reexperiencing (20%), avoidance (9%), and arousal (18%) criteria. Rates of PTSD were lowest in black males (1.5%) and higher, but similar, in the remaining groups (3.8-6.2%). Results from a multivariable logistic model indicated that exposure to the hurricane (odds ratio (OR) = 1.26, 95% confidence interval 1.13-1.41), experiencing other violent traumatic events (OR = 2.46, 95% confidence interval 1.75-3.44), being white (OR = 2.03, 95% confidence interval 1.12-3.69) and being female (OR = 2.17, 95% confidence interval 1.15-4.10) were significant correlates of PTSD.
Influence of gender role attitudes on smoking and drinking among girls from Jujuy, Argentina.
Mejia, Raul; Kaplan, Celia P; Alderete, Ethel; Gregorich, Steven E; Pérez-Stable, Eliseo J
2013-09-01
Evaluate effect of gender role attitudes on tobacco and alcohol use among Argentinean girls. Cross-sectional survey of 10th grade students attending 27 randomly selected schools in Jujuy, Argentina. Questions about tobacco and alcohol use were adapted from global youth surveys. Five items with 5-point response options of agreement-disagreement assessed attitude towards egalitarian (higher score) gender roles. 2133 girls, aged 13-18 years, 71% Indigenous, 22% mixed Indigenous/European, and 7% European responded. Of these, 60% had ever smoked, 32% were current smokers, 58% ever drinkers, 27% drank in previous month, and 13% had ≥5 drinks on one occasion. Mean response to the gender role scale was 3.49 (95% Confidence Intervals = 3.41-3.57) out of 5 tending toward egalitarian attitudes. Logistic regression models using the gender role scale score as the main predictor and adjusting for demographic and social confounders showed that egalitarian gender role was associated with ever smoking (Odds Ratio = 1.25; 95% Confidence Intervals 1.09-1.44), ever drinking (Odds Ratio = 1.24; 95% Confidence Intervals 1.10-1.40), drinking in prior month (Odds Ratio = 1.21; 95% Confidence Intervals 1.07-1.37) and ≥5 drinks on one occasion (Odds Ratio = 1.15; 95% Confidence Intervals 1.00-1.33), but was not significant for current smoking. Girls in Jujuy who reported more egalitarian gender role attitudes had higher odds of smoking or drinking. Copyright © 2013 Elsevier Inc. All rights reserved.
Haidar, Ziad A; Papanna, Ramesha; Sibai, Baha M; Tatevian, Nina; Viteri, Oscar A; Vowels, Patricia C; Blackwell, Sean C; Moise, Kenneth J
2017-08-01
Traditionally, 2-dimensional ultrasound parameters have been used for the diagnosis of a suspected morbidly adherent placenta previa. More objective techniques have not been well studied yet. The objective of the study was to determine the ability of prenatal 3-dimensional power Doppler analysis of flow and vascular indices to predict the morbidly adherent placenta objectively. A prospective cohort study was performed in women between 28 and 32 gestational weeks with known placenta previa. Patients underwent a two-dimensional gray-scale ultrasound that determined management decisions. 3-Dimensional power Doppler volumes were obtained during the same examination and vascular, flow, and vascular flow indices were calculated after manual tracing of the viewed placenta in the sweep; data were blinded to obstetricians. Morbidly adherent placenta was confirmed by histology. Severe morbidly adherent placenta was defined as increta/percreta on histology, blood loss >2000 mL, and >2 units of PRBC transfused. Sensitivities, specificities, predictive values, and likelihood ratios were calculated. Student t and χ 2 tests, logistic regression, receiver-operating characteristic curves, and intra- and interrater agreements using Kappa statistics were performed. The following results were found: (1) 50 women were studied: 23 had morbidly adherent placenta, of which 12 (52.2%) were severe morbidly adherent placenta; (2) 2-dimensional parameters diagnosed morbidly adherent placenta with a sensitivity of 82.6% (95% confidence interval, 60.4-94.2), a specificity of 88.9% (95% confidence interval, 69.7-97.1), a positive predictive value of 86.3% (95% confidence interval, 64.0-96.4), a negative predictive value of 85.7% (95% confidence interval, 66.4-95.3), a positive likelihood ratio of 7.4 (95% confidence interval, 2.5-21.9), and a negative likelihood ratio of 0.2 (95% confidence interval, 0.08-0.48); (3) mean values of the vascular index (32.8 ± 7.4) and the vascular flow index (14.2 ± 3.8) were higher in morbidly adherent placenta (P < .001); (4) area under the receiver-operating characteristic curve for the vascular and vascular flow indices were 0.99 and 0.97, respectively; (5) the vascular index ≥21 predicted morbidly adherent placenta with a sensitivity and a specificity of 95% (95% confidence interval, 88.2-96.9) and 91%, respectively (95% confidence interval, 87.5-92.4), 92% positive predictive value (95% confidence interval, 85.5-94.3), 90% negative predictive value (95% confidence interval, 79.9-95.3), positive likelihood ratio of 10.55 (95% confidence interval, 7.06-12.75), and negative likelihood ratio of 0.05 (95% confidence interval, 0.03-0.13); and (6) for the severe morbidly adherent placenta, 2-dimensional ultrasound had a sensitivity of 33.3% (95% confidence interval, 11.3-64.6), a specificity of 81.8% (95% confidence interval, 47.8-96.8), a positive predictive value of 66.7% (95% confidence interval, 24.1-94.1), a negative predictive value of 52.9% (95% confidence interval, 28.5-76.1), a positive likelihood ratio of 1.83 (95% confidence interval, 0.41-8.11), and a negative likelihood ratio of 0.81 (95% confidence interval, 0.52-1.26). A vascular index ≥31 predicted the diagnosis of a severe morbidly adherent placenta with a 100% sensitivity (95% confidence interval, 72-100), a 90% specificity (95% confidence interval, 81.7-93.8), an 88% positive predictive value (95% confidence interval, 55.0-91.3), a 100% negative predictive value (95% confidence interval, 90.9-100), a positive likelihood ratio of 10.0 (95% confidence interval, 3.93-16.13), and a negative likelihood ratio of 0 (95% confidence interval, 0-0.34). Intrarater and interrater agreements were 94% (P < .001) and 93% (P < .001), respectively. The vascular index accurately predicts the morbidly adherent placenta in patients with placenta previa. In addition, 3-dimensional power Doppler vascular and vascular flow indices were more predictive of severe cases of morbidly adherent placenta compared with 2-dimensional ultrasound. This objective technique may limit the variations in diagnosing morbidly adherent placenta because of the subjectivity of 2-dimensional ultrasound interpretations. Copyright © 2017 Elsevier Inc. All rights reserved.
Confidence intervals for distinguishing ordinal and disordinal interactions in multiple regression.
Lee, Sunbok; Lei, Man-Kit; Brody, Gene H
2015-06-01
Distinguishing between ordinal and disordinal interaction in multiple regression is useful in testing many interesting theoretical hypotheses. Because the distinction is made based on the location of a crossover point of 2 simple regression lines, confidence intervals of the crossover point can be used to distinguish ordinal and disordinal interactions. This study examined 2 factors that need to be considered in constructing confidence intervals of the crossover point: (a) the assumption about the sampling distribution of the crossover point, and (b) the possibility of abnormally wide confidence intervals for the crossover point. A Monte Carlo simulation study was conducted to compare 6 different methods for constructing confidence intervals of the crossover point in terms of the coverage rate, the proportion of true values that fall to the left or right of the confidence intervals, and the average width of the confidence intervals. The methods include the reparameterization, delta, Fieller, basic bootstrap, percentile bootstrap, and bias-corrected accelerated bootstrap methods. The results of our Monte Carlo simulation study suggest that statistical inference using confidence intervals to distinguish ordinal and disordinal interaction requires sample sizes more than 500 to be able to provide sufficiently narrow confidence intervals to identify the location of the crossover point. (c) 2015 APA, all rights reserved).
WITHDRAWN: Amnioinfusion for meconium-stained liquor in labour.
Hofmeyr, G Justus
2009-01-21
Amnioinfusion aims to prevent or relieve umbilical cord compression during labour by infusing a solution into the uterine cavity. It is also thought to dilute meconium when present in the amniotic fluid and so reduce the risk of meconium aspiration. However, it may be that the mechanism of effect is that it corrects oligohydramnios (reduced amniotic fluid), for which thick meconium staining is a marker. The objective of this review was to assess the effects of amnioinfusion for meconium-stained liquor on perinatal outcome. The Cochrane Pregnancy and Childbirth Group trials register (October 2001) and the Cochrane Controlled Trials Register (Issue 3, 2001) were searched. Randomised trials comparing amnioinfusion with no amnioinfusion for women in labour with moderate or thick meconium-staining of the amniotic fluid. Eligibility and trial quality were assessed by one reviewer. Twelve studies, most involving small numbers of participants, were included. Under standard perinatal surveillance, amnioinfusion was associated with a reduction in the following: heavy meconium staining of the liquor (relative risk 0.03, 95% confidence interval 0.01 to 0.15); variable fetal heart rate deceleration (relative risk 0.65, 95% confidence interval 0.49 to 0.88); and reduced caesarean section overall (relative risk 0.82, 95% confidence interval 0.69 to 1.97). No perinatal deaths were reported. Under limited perinatal surveillance, amnioinfusion was associated with a reduction in the following: meconium aspiration syndrome (relative risk 0.24, 95% confidence interval 0.12 to 0.48); neonatal hypoxic ischaemic encephalopathy (relative risk 0.07, 95% confidence interval 0.01 to 0.56) and neonatal ventilation or intensive care unit admission (relative risk 0.56, 95% confidence interval 0.39 to 0.79); there was a trend towards reduced perinatal mortality (relative risk 0.34, 95% confidence interval 0.11 to 1.06). Amnioinfusion is associated with improvements in perinatal outcome, particularly in settings where facilities for perinatal surveillance are limited. The trials reviewed are too small to address the possibility of rare but serious maternal adverse effects of amnioinfusion.
’Exact’ Two-Sided Confidence Intervals on Nonnegative Linear Combinations of Variances.
1980-07-01
Colorado State University ( 042_402) II. CONTrOLLING OFFICE NAME AND ADDRESS It. REPORT OAT Office of Naval Rsearch -// 1 Jul MjW80 Statistics and...MONNEGATIVE LINEAR COMBINATIONS OF VARIANCES by Franklin A. Graybill Colorado State University and Chih-Ming Wang SPSS Inc. 1. Introduction In a paper to soon...1 + a2’ called the Nodf Led Lace Sample (HLS) confidence interval, is in 2. Aoce-3Ion For DDC TAO u*.- *- -. n c edI Ju.-’I if iction_, i !~BV . . I
Wallenborn, Jordyn T; Cha, Susan; Masho, Saba W
2018-05-01
Intimate partner violence is a major public health problem that disproportionately affects women. Current literature investigating the relationship between intimate partner violence and breastfeeding is inconsistent. Research aim: This study aims to investigate the relationship between physical intimate partner violence that occurs in the preconception or prenatal period and any breastfeeding duration. Data from the retrospective, cross-sectional 2004-2014 Pregnancy Risk Assessment Monitoring System were analyzed ( N = 195,264). The outcome, breastfeeding duration, was categorized as never breastfed, breastfed 8 weeks or less, and breastfeed more than 8 weeks. Multinomial logistic regression was used to obtain crude and adjusted odds ratios and 95% confidence intervals. Approximately 6% ( n = 11,766) of survey respondents reported preconception and/or prenatal intimate partner violence, and 36.3% ( n = 67,667) of women reported never breastfeeding. The odds of discontinuing breastfeeding before 8 weeks were 18% higher among women who reported experiencing abuse 12 months before pregnancy compared with women who did not report intimate partner violence (adjusted odds ratio = 1.18; 95% confidence interval [1.01, 1.37]). All other estimates showed an overlapping 95% confidence interval. Breastfeeding is essential in improving maternal and child health; however, women in abusive relationships may face additional barriers to breastfeeding. Further research is needed to better understand the impact of violence on breastfeeding behaviors to inform healthcare practices and interventions.
Introduction to Sample Size Choice for Confidence Intervals Based on "t" Statistics
ERIC Educational Resources Information Center
Liu, Xiaofeng Steven; Loudermilk, Brandon; Simpson, Thomas
2014-01-01
Sample size can be chosen to achieve a specified width in a confidence interval. The probability of obtaining a narrow width given that the confidence interval includes the population parameter is defined as the power of the confidence interval, a concept unfamiliar to many practitioners. This article shows how to utilize the Statistical Analysis…
Evaluation of confidence intervals for a steady-state leaky aquifer model
Christensen, S.; Cooley, R.L.
1999-01-01
The fact that dependent variables of groundwater models are generally nonlinear functions of model parameters is shown to be a potentially significant factor in calculating accurate confidence intervals for both model parameters and functions of the parameters, such as the values of dependent variables calculated by the model. The Lagrangian method of Vecchia and Cooley [Vecchia, A.V. and Cooley, R.L., Water Resources Research, 1987, 23(7), 1237-1250] was used to calculate nonlinear Scheffe-type confidence intervals for the parameters and the simulated heads of a steady-state groundwater flow model covering 450 km2 of a leaky aquifer. The nonlinear confidence intervals are compared to corresponding linear intervals. As suggested by the significant nonlinearity of the regression model, linear confidence intervals are often not accurate. The commonly made assumption that widths of linear confidence intervals always underestimate the actual (nonlinear) widths was not correct. Results show that nonlinear effects can cause the nonlinear intervals to be asymmetric and either larger or smaller than the linear approximations. Prior information on transmissivities helps reduce the size of the confidence intervals, with the most notable effects occurring for the parameters on which there is prior information and for head values in parameter zones for which there is prior information on the parameters.The fact that dependent variables of groundwater models are generally nonlinear functions of model parameters is shown to be a potentially significant factor in calculating accurate confidence intervals for both model parameters and functions of the parameters, such as the values of dependent variables calculated by the model. The Lagrangian method of Vecchia and Cooley was used to calculate nonlinear Scheffe-type confidence intervals for the parameters and the simulated heads of a steady-state groundwater flow model covering 450 km2 of a leaky aquifer. The nonlinear confidence intervals are compared to corresponding linear intervals. As suggested by the significant nonlinearity of the regression model, linear confidence intervals are often not accurate. The commonly made assumption that widths of linear confidence intervals always underestimate the actual (nonlinear) widths was not correct. Results show that nonlinear effects can cause the nonlinear intervals to be asymmetric and either larger or smaller than the linear approximations. Prior information on transmissivities helps reduce the size of the confidence intervals, with the most notable effects occurring for the parameters on which there is prior information and for head values in parameter zones for which there is prior information on the parameters.
Bdair, Fadi; Akl, Elie A.; Garg, Amit X.; Thiessen-Philbrook, Heather; Salameh, Hassan; Kisra, Sood; Nesrallah, Gihad; Al-Jaishi, Ahmad; Patel, Parth; Patel, Payal; Mustafa, Ahmad A.; Schünemann, Holger J.
2016-01-01
Background and objectives Lowering the dialysate temperature may improve outcomes for patients undergoing chronic hemodialysis. We reviewed the reported benefits and harms of lower temperature dialysis. Design, setting, participants, & measurements We searched the Cochrane Central Register, OVID MEDLINE, EMBASE, and Pubmed until April 15, 2015. We reviewed the reference lists of relevant reviews, registered trials, and relevant conference proceedings. We included all randomized, controlled trials that evaluated the effect of reduced temperature dialysis versus standard temperature dialysis in adult patients receiving chronic hemodialysis. We followed the Grading of Recommendations Assessment, Development and Evaluation approach to assess confidence in the estimates of effect (i.e., the quality of evidence). We conducted meta-analyses using random effects models. Results Twenty-six trials were included, consisting of a total of 484 patients. Compared with standard temperature dialysis, reduced temperature dialysis significantly reduced the rate of intradialytic hypotension by 70% (95% confidence interval, 49% to 89%) and significantly increased intradialytic mean arterial pressure by 12 mmHg (95% confidence interval, 8 to 16 mmHg). Symptoms of discomfort occurred 2.95 (95% confidence interval, 0.88 to 9.82) times more often with reduced temperature compared with standard temperature dialysis. The effect on dialysis adequacy was not significantly different, with a Kt/V mean difference of −0.05 (95% confidence interval, −0.09 to 0.01). Small sample sizes, loss to follow-up, and a lack of appropriate blinding in some trials reduced confidence in the estimates of effect. None of the trials reported long-term outcomes. Conclusions In patients receiving chronic hemodialysis, reduced temperature dialysis may reduce the rate of intradialytic hypotension and increase intradialytic mean arterial pressure. High–quality, large, multicenter, randomized trials are needed to determine whether reduced temperature dialysis affects patient mortality and major adverse cardiovascular events. PMID:26712807
Vetter, Thomas R
2017-11-01
Descriptive statistics are specific methods basically used to calculate, describe, and summarize collected research data in a logical, meaningful, and efficient way. Descriptive statistics are reported numerically in the manuscript text and/or in its tables, or graphically in its figures. This basic statistical tutorial discusses a series of fundamental concepts about descriptive statistics and their reporting. The mean, median, and mode are 3 measures of the center or central tendency of a set of data. In addition to a measure of its central tendency (mean, median, or mode), another important characteristic of a research data set is its variability or dispersion (ie, spread). In simplest terms, variability is how much the individual recorded scores or observed values differ from one another. The range, standard deviation, and interquartile range are 3 measures of variability or dispersion. The standard deviation is typically reported for a mean, and the interquartile range for a median. Testing for statistical significance, along with calculating the observed treatment effect (or the strength of the association between an exposure and an outcome), and generating a corresponding confidence interval are 3 tools commonly used by researchers (and their collaborating biostatistician or epidemiologist) to validly make inferences and more generalized conclusions from their collected data and descriptive statistics. A number of journals, including Anesthesia & Analgesia, strongly encourage or require the reporting of pertinent confidence intervals. A confidence interval can be calculated for virtually any variable or outcome measure in an experimental, quasi-experimental, or observational research study design. Generally speaking, in a clinical trial, the confidence interval is the range of values within which the true treatment effect in the population likely resides. In an observational study, the confidence interval is the range of values within which the true strength of the association between the exposure and the outcome (eg, the risk ratio or odds ratio) in the population likely resides. There are many possible ways to graphically display or illustrate different types of data. While there is often latitude as to the choice of format, ultimately, the simplest and most comprehensible format is preferred. Common examples include a histogram, bar chart, line chart or line graph, pie chart, scatterplot, and box-and-whisker plot. Valid and reliable descriptive statistics can answer basic yet important questions about a research data set, namely: "Who, What, Why, When, Where, How, How Much?"
Hemovigilance monitoring of platelet septic reactions with effective bacterial protection systems.
Benjamin, Richard J; Braschler, Thomas; Weingand, Tina; Corash, Laurence M
2017-12-01
Delayed, large-volume bacterial culture and amotosalen/ultraviolet-A light pathogen reduction are effective at reducing the risk of bacterial proliferation in platelet concentrates (PCs). Hemovigilance programs continue to receive reports of suspected septic transfusion reactions, most with low imputability. Here, we compile national hemovigilance data to determine the relative efficacy of these interventions. Annual reports from the United Kingdom, France, Switzerland, and Belgium were reviewed between 2005 and 2016 to assess the risk of bacterial contamination and septic reactions. Approximately 1.65 million delayed, large-volume bacterial culture-screened PCs in the United Kingdom and 2.3 million amotosalen/ultraviolet-A-treated PCs worldwide were issued with no reported septic fatalities. One definite, one possible, and 12 undetermined/indeterminate septic reactions and eight contaminated "near misses" were reported with delayed, large-volume bacterial cultures between 2011 and 2016, for a lower false-negative culture rate than that in the previous 5 years (5.4 vs. 16.3 per million: odds ratio, 3.0; 95% confidence interval, 1.4-6.5). Together, the Belgian, Swiss, and French hemovigilance programs documented zero probable or definite/certain septic reactions with 609,290 amotosalen/ultraviolet-A-treated PCs (<1.6 per million). The rates were significantly lower than those reported with concurrently transfused, nonpathogen-reduced PCs in Belgium (<4.4 vs. 35.6 per million: odds ratio, 8.1; 95% confidence interval,1.1-353.3) and with historic septic reaction rates in Switzerland (<6.0 vs. 82.9 per million: odds ratio, 13.9; 95% confidence interval, 2.1-589.2), and the rates tended to be lower than those from concurrently transfused, nonpathogen-reduced PCs in France (<4.7 vs. 19.0 per million: odds ratio, 4.1; 95% confidence interval, 0.7-164.3). Pathogen reduction and bacterial culture both reduced the incidence of septic reactions, although under-reporting and strict imputability criteria resulted in an underestimation of risk. © 2017 The Authors Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.
Hoyt, Adrienne T; Canfield, Mark A; Romitti, Paul A; Botto, Lorenzo D; Anderka, Marlene T; Krikov, Sergey V; Tarpey, Morgan K; Feldkamp, Marcia L
2016-11-01
While associations between secondhand smoke and a few birth defects (namely, oral clefts and neural tube defects) have been noted in the scientific literature, to our knowledge, there is no single or comprehensive source of population-based information on its associations with a range of birth defects among nonsmoking mothers. We utilized data from the National Birth Defects Prevention Study, a large population-based multisite case-control study, to examine associations between maternal reports of periconceptional exposure to secondhand smoke in the household or workplace/school and major birth defects. The multisite National Birth Defects Prevention Study is the largest case-control study of birth defects to date in the United States. We selected cases from birth defect groups having >100 total cases, as well as all nonmalformed controls (10,200), from delivery years 1997 through 2009; 44 birth defects were examined. After excluding cases and controls from multiple births and whose mothers reported active smoking or pregestational diabetes, we analyzed data on periconceptional secondhand smoke exposure-encompassing the period 1 month prior to conception through the first trimester. For the birth defect craniosynostosis, we additionally examined the effect of exposure in the second and third trimesters as well due to the potential sensitivity to teratogens for this defect throughout pregnancy. Covariates included in all final models of birth defects with ≥5 exposed mothers were study site, previous live births, time between estimated date of delivery and interview date, maternal age at estimated date of delivery, race/ethnicity, education, body mass index, nativity, household income divided by number of people supported by this income, periconceptional alcohol consumption, and folic acid supplementation. For each birth defect examined, we used logistic regression analyses to estimate both crude and adjusted odds ratios and 95% confidence intervals for both isolated and total case groups for various sources of exposure (household only; workplace/school only; household and workplace/school; household or workplace/school). The prevalence of secondhand smoke exposure only across all sources ranged from 12.9-27.8% for cases and 14.5-15.8% for controls. The adjusted odds ratios for any vs no secondhand smoke exposure in the household or workplace/school and isolated birth defects were significantly elevated for neural tube defects (anencephaly: adjusted odds ratio, 1.66; 95% confidence interval, 1.22-2.25; and spina bifida: adjusted odds ratio, 1.49; 95% confidence interval, 1.20-1.86); orofacial clefts (cleft lip without cleft palate: adjusted odds ratio, 1.41; 95% confidence interval, 1.10-1.81; cleft lip with or without cleft palate: adjusted odds ratio, 1.24; 95% confidence interval, 1.05-1.46; cleft palate alone: adjusted odds ratio, 1.31; 95% confidence interval, 1.06-1.63); bilateral renal agenesis (adjusted odds ratio, 1.99; 95% confidence interval, 1.05-3.75); amniotic band syndrome-limb body wall complex (adjusted odds ratio, 1.66; 95% confidence interval, 1.10-2.51); and atrial septal defects, secundum (adjusted odds ratio, 1.37; 95% confidence interval, 1.09-1.72). There were no significant inverse associations observed. Additional studies replicating the findings are needed to better understand the moderate positive associations observed between periconceptional secondhand smoke and several birth defects in this analysis. Increased odds ratios resulting from chance (eg, multiple comparisons) or recall bias cannot be ruled out. Copyright © 2016 Elsevier Inc. All rights reserved.
New estimates of elasticity of demand for healthcare in rural China.
Zhou, Zhongliang; Su, Yanfang; Gao, Jianmin; Xu, Ling; Zhang, Yaoguang
2011-12-01
Only limited empirical studies reported own-price elasticity of demand for health care in rural China. Neither research on income elasticity of demand for health care nor cross-price elasticity of demand for inpatient versus outpatient services in rural China has been reported. However, elasticity of demand is informative to evaluate current policy and to guide further policy making. Our study contributes to the literature by estimating three elasticities (i.e., own-price elasticity, cross-price elasticity, and income elasticity of demand for health care based on nationwide-representative data. We aim to answer three empirical questions with regard to health expenditure in rural China: (1) Which service is more sensitive to price change, outpatient or inpatient service? (2) Is outpatient service a substitute or complement to inpatient service? and (3) Does demand for inpatient services grow faster than demand for outpatient services with income growth? Based on data from a National Health Services Survey, a Probit regression model with probability of outpatient visit and probability of inpatient visit as dependent variables and a zero-truncated negative binomial regression model with outpatient visits as dependent variable were constructed to isolate the effects of price and income on demand for health care. Both pooled and separated regressions for 2003 and 2008 were conducted with tests of robustness. Own-price elasticities of demand for first outpatient visit, outpatient visits among users and first inpatient visit are -0.519 [95% confidence interval (-0.703, -0.336)], -0.547 [95% confidence interval (-0.747, -0.347)] and -0.372 [95% confidence interval (-0.517, -0.226)], respectively. Cross-price elasticities of demand for first outpatient visit, outpatient visits among users and first inpatient visit are 0.073 [95% confidence interval (-0.176, 0.322)], 0.308 [95% confidence interval (0.087, 0.528)], and 0.059 [95% confidence interval (-0.085, 0.204)], respectively. Income elasticities of demand for first outpatient visit, outpatient visits among users and first inpatient visit are 0.098 [95% confidence interval (0.018, 0.178)], 0.136 [95% confidence interval (0.028, 0.245)] and 0.521 [95% confidence interval (0.438, 0.605)], respectively. The aforementioned results are in 2008, which hold similar pattern as results in 2003 as well as results from pooled data of two periods. First, no significant difference is detected between sensitivity of outpatient services and sensitivity of inpatient services, responding to own-price change. Second, inpatient services are substitutes to outpatient services. Third, the growth of inpatient services is faster than the growth in outpatient services in response to income growth. The major findings from this paper suggest refining insurance policy in rural China. First, from a cost-effectiveness perspective, changing outpatient price is at least as effective as changing inpatient price to adjust demand of health care. Second, the current national guideline of healthcare reform to increase the reimbursement rate for inpatient services will crowd out outpatient services; however, we have no evidence about the change in demand for inpatient service if insurance covers outpatient services. Third, a referral system and gate-keeping system should be established to guide rural patients to utilize outpatient service. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Jackson, Dan; Bowden, Jack
2016-09-07
Confidence intervals for the between study variance are useful in random-effects meta-analyses because they quantify the uncertainty in the corresponding point estimates. Methods for calculating these confidence intervals have been developed that are based on inverting hypothesis tests using generalised heterogeneity statistics. Whilst, under the random effects model, these new methods furnish confidence intervals with the correct coverage, the resulting intervals are usually very wide, making them uninformative. We discuss a simple strategy for obtaining 95 % confidence intervals for the between-study variance with a markedly reduced width, whilst retaining the nominal coverage probability. Specifically, we consider the possibility of using methods based on generalised heterogeneity statistics with unequal tail probabilities, where the tail probability used to compute the upper bound is greater than 2.5 %. This idea is assessed using four real examples and a variety of simulation studies. Supporting analytical results are also obtained. Our results provide evidence that using unequal tail probabilities can result in shorter 95 % confidence intervals for the between-study variance. We also show some further results for a real example that illustrates how shorter confidence intervals for the between-study variance can be useful when performing sensitivity analyses for the average effect, which is usually the parameter of primary interest. We conclude that using unequal tail probabilities when computing 95 % confidence intervals for the between-study variance, when using methods based on generalised heterogeneity statistics, can result in shorter confidence intervals. We suggest that those who find the case for using unequal tail probabilities convincing should use the '1-4 % split', where greater tail probability is allocated to the upper confidence bound. The 'width-optimal' interval that we present deserves further investigation.
Self-reported sleepwalking in Australian senior secondary school students.
Stallman, H M; Kohler, M; Wilson, A; Biggs, S; Dollman, J; Martin, J; Kennedy, D; Lushington, K
2016-09-01
Few studies have examined self-reported sleepwalking in older adolescents. The aim of this study was to examine the prevalence rates of sleepwalking in a one-month self-report period in Australian adolescents. Participants were 532 Australian adolescents in their final two years of secondary school. The prevalence of sleepwalking in the one-month self-report period was 2.9% (95% confidence interval (CI) 1.47-4.33) in this sample-1% reported sleepwalking at least once a week in the previous month. A significant proportion (17.5%) of the participants was unsure if they had sleepwalked. The results provide data on the self-reported prevalence rate of sleepwalking in older adolescents. Compared with the population data, this rate falls within the confidence intervals of child and adult prevalence rates of sleepwalking and is consistent with a decline in sleepwalking from childhood and adulthood. Further research is needed to explore how adolescents know they sleepwalk to understand the reliability of self-report measures. Copyright © 2016 Elsevier B.V. All rights reserved.
Does the experience of discrimination affect health? A cross-sectional study of Korean elders.
Chun, Heeran; Kang, Minah; Cho, Sung-il; Jung-Choi, Kyunghee; Jang, Soong-Nang; Khang, Young-Ho
2015-03-01
This study was conducted among 992 Koreans aged 60 to 89 to examine the effects of perceived discrimination on the health of an ethnically homogenous older population. Perceived discrimination was measured with a self-report instrument. Health outcomes included depressive symptoms, poor self-rated health, and chronic diseases. Of the elderly Koreans surveyed, 23.5% reported having experienced discrimination based on education, age, birthplace, birth order, or gender. Among women, 23.1% reported experiencing gender discrimination, compared to 0.9% among men. Men reported education and age discrimination most frequently-9.4% and 7.7%, respectively. Those who reported experiencing any discrimination were 2.19 times more likely to report depressive symptoms (95% confidence interval = 1.50-3.22) and 1.40 times more likely to report poor self-rated health (95% confidence interval = 1.02-1.93). The health effects of educational discrimination appeared most prominent. This study supports the positive associations between perceived discrimination and poorer health, particularly mental health, in later life. © 2013 APJPH.
Doubly Bayesian Analysis of Confidence in Perceptual Decision-Making.
Aitchison, Laurence; Bang, Dan; Bahrami, Bahador; Latham, Peter E
2015-10-01
Humans stand out from other animals in that they are able to explicitly report on the reliability of their internal operations. This ability, which is known as metacognition, is typically studied by asking people to report their confidence in the correctness of some decision. However, the computations underlying confidence reports remain unclear. In this paper, we present a fully Bayesian method for directly comparing models of confidence. Using a visual two-interval forced-choice task, we tested whether confidence reports reflect heuristic computations (e.g. the magnitude of sensory data) or Bayes optimal ones (i.e. how likely a decision is to be correct given the sensory data). In a standard design in which subjects were first asked to make a decision, and only then gave their confidence, subjects were mostly Bayes optimal. In contrast, in a less-commonly used design in which subjects indicated their confidence and decision simultaneously, they were roughly equally likely to use the Bayes optimal strategy or to use a heuristic but suboptimal strategy. Our results suggest that, while people's confidence reports can reflect Bayes optimal computations, even a small unusual twist or additional element of complexity can prevent optimality.
Improved confidence intervals when the sample is counted an integer times longer than the blank.
Potter, William Edward; Strzelczyk, Jadwiga Jodi
2011-05-01
Past computer solutions for confidence intervals in paired counting are extended to the case where the ratio of the sample count time to the blank count time is taken to be an integer, IRR. Previously, confidence intervals have been named Neyman-Pearson confidence intervals; more correctly they should have been named Neyman confidence intervals or simply confidence intervals. The technique utilized mimics a technique used by Pearson and Hartley to tabulate confidence intervals for the expected value of the discrete Poisson and Binomial distributions. The blank count and the contribution of the sample to the gross count are assumed to be Poisson distributed. The expected value of the blank count, in the sample count time, is assumed known. The net count, OC, is taken to be the gross count minus the product of IRR with the blank count. The probability density function (PDF) for the net count can be determined in a straightforward manner.
Cooley, Richard L.
1993-01-01
Calibration data (observed values corresponding to model-computed values of dependent variables) are incorporated into a general method of computing exact Scheffé-type confidence intervals analogous to the confidence intervals developed in part 1 (Cooley, this issue) for a function of parameters derived from a groundwater flow model. Parameter uncertainty is specified by a distribution of parameters conditioned on the calibration data. This distribution was obtained as a posterior distribution by applying Bayes' theorem to the hydrogeologically derived prior distribution of parameters from part 1 and a distribution of differences between the calibration data and corresponding model-computed dependent variables. Tests show that the new confidence intervals can be much smaller than the intervals of part 1 because the prior parameter variance-covariance structure is altered so that combinations of parameters that give poor model fit to the data are unlikely. The confidence intervals of part 1 and the new confidence intervals can be effectively employed in a sequential method of model construction whereby new information is used to reduce confidence interval widths at each stage.
Acceptance of technology-based tools in a sample of Parkinson's patients.
Duroseau, Nathalie; Abramson, Tobi; Pergament, Kathleen; Chan, Vivian; Govindavari, John Paul; Ciraco, Christina; Tegay, David; Krishnamachari, Bhuma
2017-03-01
Objectives Parkinson's disease is the second most common neurodegenerative movement disorder in the United States. Patients' opinions of technology-based tools for education and communication as related to Parkinson's disease are unclear with little documented research addressing the issue. The goal of this research was to investigate patient opinions about technology-based tools with a focus on differences between patients of different age groups. Methods A cross-sectional survey was used to assess views on using multiple different electronic methods for receiving instructions and communicating with healthcare providers in 109 Parkinson's disease patients. Results Approximately 28% (n = 28) of the subjects reported having unmet needs related to Parkinson's disease. Those 65 and over were less likely to believe that using technology to communicate with the healthcare center would result in themselves having a better understanding of their care (odds ratio = 0.36, 95% confidence interval: 0.14, 0.95). Those over 75 had a lower odds of being willing to use electronic methods (odds ratio = 0.33, 95% confidence interval: 0.14, 0.79), a lower odds of believing that technology would result in better self-understanding of medical needs (odds ratio = 0.27, 95% confidence interval: 0.12, 0.63) and a lower odds of believing that technology would result in their healthcare providers better understanding their needs (odds ratio = 0.32, 95% confidence interval: 0.14, 0.73). Discussion The results of this study indicate that older Parkinson's disease patients report a less favorable view regarding the role of technology in communicating with healthcare providers and for understanding their care.
Ottawa, Cassandra; Sposato, Luciano A; Nabbouh, Fadl; Saposnik, Gustavo
2015-10-01
If translated into behavioral intent, improving stroke knowledge may potentially impact on better outcomes. Children are an attractive target population since they can drive familial behavioral changes. However, the impact of interventions on stroke knowledge among children is unclear. We performed a systematic review and meta-analysis to investigate whether educational interventions targeting children improve stroke knowledge and lead to behavioral changes. We searched Ovid, PubMed, and Embase between January 2000 and December 2014. We included studies written in English reporting the number of children aged 6-15 years undergoing educational interventions on stroke and providing the results for baseline and early and late postintervention tests. We compared the proportion of correct answers between baseline, early, and late responses for two endpoints: knowledge and behavioral intent. Of the initial 58 articles found, we included nine that met the inclusion criteria. Compared with baseline tests (51·7%, 95% confidence interval 40·9-62·4), there was improvement in stroke knowledge in early (74·0%, 95% confidence interval 64·4-82·5, P = 0·002) and late (67·3%, 95% confidence interval 55·4-78·2, P = 0·027) responses. There was improvement in the early (92·1%, 95% confidence interval 86·0-96·6, P < 0·001) and late (83·9%, 95% confidence interval 73·5-92·1, P = 0·001) responses for behavioral intent compared with the baseline assessment (63·8%, 95% confidence interval 53·5-73·4). Children are a potentially attractive target population for improvement in stroke knowledge and behavioral intent, both in the short and long term. Our findings may support the implementation of large-scale stroke educational initiatives targeting children. © 2015 World Stroke Organization.
Lanzieri, Tatiana M; Cunha, Clóvis Arns da; Cunha, Rejane B; Arguello, D Fermin; Devadiga, Raghavendra; Sanchez, Nervo; Barria, Eduardo Ortega
To estimate acute otitis media incidence among young children and impact on quality of life of parents/caregivers in a southern Brazilian city. Prospective cohort study including children 0-5 years of age registered at a private pediatric practice. Acute otitis media episodes diagnosed by a pediatrician and impact on quality of life of parents/caregivers were assessed during a 12-month follow-up. During September 2008-March 2010, of 1,136 children enrolled in the study, 1074 (95%) were followed: 55.0% were ≤2 years of age, 52.3% males, 94.7% white, and 69.2% had previously received pneumococcal vaccine in private clinics. Acute otitis media incidence per 1000 person-years was 95.7 (95% confidence interval: 77.2-117.4) overall, 105.5 (95% confidence interval: 78.3-139.0) in children ≤2 years of age and 63.6 (95% confidence interval: 43.2-90.3) in children 3-5 years of age. Acute otitis media incidence per 1000 person-years was 86.3 (95% confidence interval: 65.5-111.5) and 117.1 (95% confidence interval: 80.1-165.3) among vaccinated and unvaccinated children, respectively. Nearly 68.9% of parents reported worsening of their overall quality of life. Acute otitis media incidence among unvaccinated children in our study may be useful as baseline data to assess impact of pneumococcal vaccine introduction in the Brazilian National Immunization Program in April 2010. Copyright © 2017 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.
Somatic Complaints in Adolescence and Labour Market Participation in Young Adulthood.
Winding, Trine Nøhr; Andersen, Johan Hviid
2018-05-01
The primary aim was to investigate the association between somatic symptoms at ages 15 or 18 and reduced labour market participation at age 23, when socioeconomic, social, and mental health risk factors were taken into account. The study included 3223 participants from the West Jutland Cohort Study with questionnaire information on somatic symptoms at ages 15 or 18 and with register information on labour market participation at age 23, gathered from a national register on all public transfer benefits for a 52-week period. The analyses included additional information about socioeconomic background, number of negative life events, social climate in the family, social relations with friends, and depressive symptoms. Logistic regression analyses yielded odds ratios with 95% confidence intervals. Among the males, associations between reporting somatic symptoms at age 18 and low labour market participation was seen in both crude and adjusted analyses (odds ratio: 1.66; 95% confidence intervals: 1.01-2.75), whereas the association among the females disappeared after adjustments (odds ratio: 0.97; 95% confidence intervals: 0.63-1.52). The males that reported somatic symptoms in late adolescence appeared to be the most vulnerable to future reduced labour market participation.
Hospitalization of abused and neglected children.
Marshall, W N
1997-03-01
To describe the use of inpatient hospitalization for abused and neglected children living in a metropolitan area. Retrospective record review of abused and neglected children admitted in 1992 and 1993 to hospitals with 87% of metropolitan area pediatric admissions; comparison of these data with population, crisis nursery, and child protective services data. Thirty-four abused and neglected children were admitted to hospital, representing 0.3% (34/11,066; 95% confidence interval, 0%-1.2%) of pediatric admissions and 0.2% (34/19,950; 95% confidence interval, 0%-0.6%) of child protective services reports. This represents a rate of hospitalization for child abuse of 10 children (95% confidence interval, 0-46) per 100,000 child population per year. Seven hundred fifteen children were admitted to the crisis nursery by child protective services. Of those admitted to the hospital, 12 needed intensive care, 5 of whom died. Only 3 of 34 hospital-admitted children had private health insurance; 19 of 34 were younger than 1 year. Inpatient hospitalization for abuse represented a small fraction of total pediatric admissions and of child protective services reports. Comprehensive medical care for most abused children and medical education about child abuse must occur in outpatient settings.
Hypnotherapy for disability-related pain: A meta-analysis.
Bowker, Emma; Dorstyn, Diana
2016-04-01
Hypnotherapy can address the biopsychosocial aspects of disability-related pain, although the available evidence is limited in quality and quantity. Meta-analytic techniques were utilised to evaluate 10 controlled studies. Hypnotherapy produced significant short-term improvements in fatigue, pain experience and affect. However, a lack of significance was noted at 3- to 6-month follow-up. A beneficial effect size (d(w)= 0.53; confidence interval = 0.28-0.84) in comparison to control conditions was reported, although comparability with other cognitive-behavioural treatments could not be confirmed across the few studies reporting this data (d(w)= 0.06; confidence interval = -0.33 to 0.45). The findings highlight the need for further controlled and longitudinal research in this area. © The Author(s) 2014.
Physical activity and mortality: is the association explained by genetic selection?
Carlsson, Sofia; Andersson, Tomas; Lichtenstein, Paul; Michaëlsson, Karl; Ahlbom, Anders
2007-08-01
Public health recommendations promote physical activity to improve health and longevity. Recent data suggest that the association between physical activity and mortality may be due to genetic selection. Using data on twins, the authors investigated whether genetic selection explains the association between physical activity and mortality. Data were based on a postal questionnaire answered by 13,109 Swedish twin pairs in 1972. The national Cause of Death Register was used for information about all-cause mortality (n=1,800) and cardiovascular disease mortality (n=638) during 1975-2004. The risk of death was reduced by 34% for men (relative risk=0.64, 95% confidence interval: 0.50, 0.83) and by 25% for women (relative risk=0.75, 95% confidence interval: 0.50, 1.14) reporting high physical activity levels. Within-pair comparisons of monozygotic twins showed that, compared with their less active co-twin, the more active twin had a 20% (odds ratio=0.80, 95% confidence interval: 0.65, 0.99) reduced risk of all-cause mortality and a 32% (odds ratio=0.68, 95% confidence interval: 0.49, 0.95) reduced risk of cardiovascular disease mortality. Results indicate that physical activity is associated with a reduced risk of mortality not due to genetic selection. This finding supports a causal link between physical activity and mortality.
Ma, Heng; Yang, Jun; Liu, Jing; Ge, Lan; An, Jing; Tang, Qing; Li, Han; Zhang, Yu; Chen, David; Wang, Yong; Liu, Jiabin; Liang, Zhigang; Lin, Kai; Jin, Lixin; Bi, Xiaoming; Li, Kuncheng; Li, Debiao
2012-04-15
Myocardial perfusion magnetic resonance imaging (MRI) with sliding-window conjugate-gradient highly constrained back-projection reconstruction (SW-CG-HYPR) allows whole left ventricular coverage, improved temporal and spatial resolution and signal/noise ratio, and reduced cardiac motion-related image artifacts. The accuracy of this technique for detecting coronary artery disease (CAD) has not been determined in a large number of patients. We prospectively evaluated the diagnostic performance of myocardial perfusion MRI with SW-CG-HYPR in patients with suspected CAD. A total of 50 consecutive patients who were scheduled for coronary angiography with suspected CAD underwent myocardial perfusion MRI with SW-CG-HYPR at 3.0 T. The perfusion defects were interpreted qualitatively by 2 blinded observers and were correlated with x-ray angiographic stenoses ≥50%. The prevalence of CAD was 56%. In the per-patient analysis, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of SW-CG-HYPR was 96% (95% confidence interval 82% to 100%), 82% (95% confidence interval 60% to 95%), 87% (95% confidence interval 70% to 96%), 95% (95% confidence interval 74% to100%), and 90% (95% confidence interval 82% to 98%), respectively. In the per-vessel analysis, the corresponding values were 98% (95% confidence interval 91% to 100%), 89% (95% confidence interval 80% to 94%), 86% (95% confidence interval 76% to 93%), 99% (95% confidence interval 93% to 100%), and 93% (95% confidence interval 89% to 97%), respectively. In conclusion, myocardial perfusion MRI using SW-CG-HYPR allows whole left ventricular coverage and high resolution and has high diagnostic accuracy in patients with suspected CAD. Copyright © 2012 Elsevier Inc. All rights reserved.
Enzyme replacement therapy for Anderson-Fabry disease.
El Dib, Regina; Gomaa, Huda; Carvalho, Raíssa Pierri; Camargo, Samira E; Bazan, Rodrigo; Barretti, Pasqual; Barreto, Fellype C
2016-07-25
Anderson-Fabry disease is an X-linked defect of glycosphingolipid metabolism. Progressive renal insufficiency is a major source of morbidity, additional complications result from cardio- and cerebro-vascular involvement. Survival is reduced among affected males and symptomatic female carriers.This is an update of a Cochrane review first published in 2010, and previously updated in 2013. To evaluate the effectiveness and safety of enzyme replacement therapy compared to other interventions, placebo or no interventions, for treating Anderson-Fabry disease. We searched the Cystic Fibrosis and Genetic Disorders Group's Inborn Errors of Metabolism Trials Register (date of the most recent search: 08 July 2016). We also searched 'Clinical Trials' on The Cochrane Library, MEDLINE, Embase and LILACS (date of the most recent search: 24 September 2015). Randomized controlled trials of agalsidase alfa or beta in participants diagnosed with Anderson-Fabry disease. Two authors selected relevant trials, assessed methodological quality and extracted data. Nine trials comparing either agalsidase alfa or beta in 351 participants fulfilled the selection criteria.Both trials comparing agalsidase alfa to placebo reported on globotriaosylceramide concentration in plasma and tissue; aggregate results were non-significant. One trial reported pain scores measured by the Brief Pain Inventory severity, there was a statistically significant improvement for participants receiving treatment at up to three months, mean difference -2.10 (95% confidence interval -3.79 to -0.41; at up to five months, mean difference -1.90 (95% confidence interval -3.65 to -0.15); and at up to six months, mean difference -2.00 (95% confidence interval -3.66 to -0.34). There was a significant difference in the Brief Pain Inventory pain-related quality of life at over five months and up to six months, mean difference -2.10 (95% confidence interval -3.92 to -0.28) but not at other time points. Death was not an outcome in either of the trials.One of the three trials comparing agalsidase beta to placebo reported on globotriaosylceramide concentration in plasma and tissue and showed significant improvement: kidney, mean difference -1.70 (95% confidence interval -2.09 to -1.31); heart, mean difference -0.90 (95% confidence interval -1.18 to -0.62); and composite results (renal, cardiac, and cerebrovascular complications and death), mean difference -4.80 (95% confidence interval -5.45 to -4.15). There was no significant difference between groups for death; no trials reported on pain.Only two trials compared agalsidase alfa to agalsidase beta. One of them showed no significant difference between the groups regarding adverse events, risk ratio 0.36 (95% confidence interval 0.08 to 1.59), or any serious adverse events; risk ratio 0.30; (95% confidence interval 0.03 to 2.57).Two trials compared different dosing schedules of agalsidase alfa. One of them involved three different doses (0.2 mg/kg every two weeks; 0.1 mg/kg weekly and; 0.2 mg/kg weekly), the other trial evaluated two further doses to the dosage schedules: 0.4 mg/kg every week and every other week. Both trials failed to show significant differences with various dosing schedules on globotriaosylceramide levels. No significant differences were found among the schedules for the primary efficacy outcome of self-assessed health state, or for pain scores.One trial comparing agalsidase alfa to agalsidase beta showed no significant difference for any adverse events such as dyspnoea and hypertension.The methodological quality of the included trials was generally unclear for the random sequence generation and allocation concealment. Trials comparing enzyme replacement therapy to placebo show significant improvement with enzyme replacement therapy in regard to microvascular endothelial deposits of globotriaosylceramide and in pain-related quality of life. There is, however, no evidence identifying if the alfa or beta form is superior or the optimal dose or frequency of enzyme replacement therapy. With regards to safety, adverse events (i.e., rigors, fever) were more significant in the agalsidase beta as compared to placebo. The long-term influence of enzyme replacement therapy on risk of morbidity and mortality related to Anderson-Fabry disease remains to be established. This review highlights the need for continued research into the use of enzyme replacement therapy for Anderson-Fabry disease.
Explorations in Statistics: Confidence Intervals
ERIC Educational Resources Information Center
Curran-Everett, Douglas
2009-01-01
Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This third installment of "Explorations in Statistics" investigates confidence intervals. A confidence interval is a range that we expect, with some level of confidence, to include the true value of a population parameter…
Winslow, Stephen D; Pepich, Barry V; Martin, John J; Hallberg, George R; Munch, David J; Frebis, Christopher P; Hedrick, Elizabeth J; Krop, Richard A
2006-01-01
The United States Environmental Protection Agency's Office of Ground Water and Drinking Water has developed a single-laboratory quantitation procedure: the lowest concentration minimum reporting level (LCMRL). The LCMRL is the lowest true concentration for which future recovery is predicted to fall, with high confidence (99%), between 50% and 150%. The procedure takes into account precision and accuracy. Multiple concentration replicates are processed through the entire analytical method and the data are plotted as measured sample concentration (y-axis) versus true concentration (x-axis). If the data support an assumption of constant variance over the concentration range, an ordinary least-squares regression line is drawn; otherwise, a variance-weighted least-squares regression is used. Prediction interval lines of 99% confidence are drawn about the regression. At the points where the prediction interval lines intersect with data quality objective lines of 50% and 150% recovery, lines are dropped to the x-axis. The higher of the two values is the LCMRL. The LCMRL procedure is flexible because the data quality objectives (50-150%) and the prediction interval confidence (99%) can be varied to suit program needs. The LCMRL determination is performed during method development only. A simpler procedure for verification of data quality objectives at a given minimum reporting level (MRL) is also presented. The verification procedure requires a single set of seven samples taken through the entire method procedure. If the calculated prediction interval is contained within data quality recovery limits (50-150%), the laboratory performance at the MRL is verified.
A prospective study of the natural history of urinary incontinence in women.
Hagan, Kaitlin A; Erekson, Elisabeth; Austin, Andrea; Minassian, Vatche A; Townsend, Mary K; Bynum, Julie P W; Grodstein, Francine
2018-05-01
Symptoms of urinary incontinence are commonly perceived to vary over time; yet, there is limited quantitative evidence regarding the natural history of urinary incontinence, especially over the long term. We sought to delineate the course of urinary incontinence symptoms over time, using 2 large cohorts of middle-aged and older women, with data collected over 10 years. We studied 9376 women from the Nurses' Health Study, age 56-81 years at baseline, and 7491 women from the Nurses' Health Study II, age 39-56 years, with incident urinary incontinence in 2002 through 2003. Urinary incontinence severity was measured by the Sandvik severity index. We tracked persistence, progression, remission, and improvement of symptoms over 10 years. We also examined risk factors for urinary incontinence progression using logistic regression models. Among women age 39-56 years, 39% had slight, 45% had moderate, and 17% had severe urinary incontinence at onset. Among women age 56-81 years, 34% had slight, 45% had moderate, and 21% had severe urinary incontinence at onset. Across ages, most women reported persistence or progression of symptoms over follow-up; few (3-11%) reported remission. However, younger women and women with less severe urinary incontinence at onset were more likely to report remission or improvement of symptoms. We found that increasing age was associated with higher odds of progression only among older women (age 75-81 vs 56-60 years; odds ratio, 1.84; 95% confidence interval, 1.51-2.25). Among all women, higher body mass index was strongly associated with progression (younger women: odds ratio, 2.37; 95% confidence interval, 2.00-2.81; body mass index ≥30 vs <25 kg/m 2 ; older women: odds ratio, 1.93; 95% confidence interval, 1.62-2.22). Additionally, greater physical activity was associated with lower odds of progression to severe urinary incontinence (younger women: odds ratio, 0.86; 95% confidence interval, 0.71-1.03; highest vs lowest quartile of activity; older women: odds ratio, 0.68; 95% confidence interval, 0.59-0.80). Most women with incident urinary incontinence continued to experience symptoms over 10 years; few had complete remission. Identification of risk factors for urinary incontinence progression, such as body mass index and physical activity, could be important for reducing symptoms over time. Copyright © 2018 Elsevier Inc. All rights reserved.
Using an R Shiny to Enhance the Learning Experience of Confidence Intervals
ERIC Educational Resources Information Center
Williams, Immanuel James; Williams, Kelley Kim
2018-01-01
Many students find understanding confidence intervals difficult, especially because of the amalgamation of concepts such as confidence levels, standard error, point estimates and sample sizes. An R Shiny application was created to assist the learning process of confidence intervals using graphics and data from the US National Basketball…
Alternative Confidence Interval Methods Used in the Diagnostic Accuracy Studies
Gülhan, Orekıcı Temel
2016-01-01
Background/Aim. It is necessary to decide whether the newly improved methods are better than the standard or reference test or not. To decide whether the new diagnostics test is better than the gold standard test/imperfect standard test, the differences of estimated sensitivity/specificity are calculated with the help of information obtained from samples. However, to generalize this value to the population, it should be given with the confidence intervals. The aim of this study is to evaluate the confidence interval methods developed for the differences between the two dependent sensitivity/specificity values on a clinical application. Materials and Methods. In this study, confidence interval methods like Asymptotic Intervals, Conditional Intervals, Unconditional Interval, Score Intervals, and Nonparametric Methods Based on Relative Effects Intervals are used. Besides, as clinical application, data used in diagnostics study by Dickel et al. (2010) has been taken as a sample. Results. The results belonging to the alternative confidence interval methods for Nickel Sulfate, Potassium Dichromate, and Lanolin Alcohol are given as a table. Conclusion. While preferring the confidence interval methods, the researchers have to consider whether the case to be compared is single ratio or dependent binary ratio differences, the correlation coefficient between the rates in two dependent ratios and the sample sizes. PMID:27478491
Alternative Confidence Interval Methods Used in the Diagnostic Accuracy Studies.
Erdoğan, Semra; Gülhan, Orekıcı Temel
2016-01-01
Background/Aim. It is necessary to decide whether the newly improved methods are better than the standard or reference test or not. To decide whether the new diagnostics test is better than the gold standard test/imperfect standard test, the differences of estimated sensitivity/specificity are calculated with the help of information obtained from samples. However, to generalize this value to the population, it should be given with the confidence intervals. The aim of this study is to evaluate the confidence interval methods developed for the differences between the two dependent sensitivity/specificity values on a clinical application. Materials and Methods. In this study, confidence interval methods like Asymptotic Intervals, Conditional Intervals, Unconditional Interval, Score Intervals, and Nonparametric Methods Based on Relative Effects Intervals are used. Besides, as clinical application, data used in diagnostics study by Dickel et al. (2010) has been taken as a sample. Results. The results belonging to the alternative confidence interval methods for Nickel Sulfate, Potassium Dichromate, and Lanolin Alcohol are given as a table. Conclusion. While preferring the confidence interval methods, the researchers have to consider whether the case to be compared is single ratio or dependent binary ratio differences, the correlation coefficient between the rates in two dependent ratios and the sample sizes.
Modified Confidence Intervals for the Mean of an Autoregressive Process.
1985-08-01
Validity of the method 45 3.6 Theorem 47 4 Derivation of corrections 48 Introduction 48 The zero order pivot 50 4.1 Algorithm 50 CONTENTS The first...of standard confidence intervals. There are several standard methods of setting confidence intervals in simulations, including the regener- ative... method , batch means, and time series methods . We-will focus-s on improved confidence intervals for the mean of an autoregressive process, and as such our
Publication Bias in Meta-Analysis: Confidence Intervals for Rosenthal's Fail-Safe Number.
Fragkos, Konstantinos C; Tsagris, Michail; Frangos, Christos C
2014-01-01
The purpose of the present paper is to assess the efficacy of confidence intervals for Rosenthal's fail-safe number. Although Rosenthal's estimator is highly used by researchers, its statistical properties are largely unexplored. First of all, we developed statistical theory which allowed us to produce confidence intervals for Rosenthal's fail-safe number. This was produced by discerning whether the number of studies analysed in a meta-analysis is fixed or random. Each case produces different variance estimators. For a given number of studies and a given distribution, we provided five variance estimators. Confidence intervals are examined with a normal approximation and a nonparametric bootstrap. The accuracy of the different confidence interval estimates was then tested by methods of simulation under different distributional assumptions. The half normal distribution variance estimator has the best probability coverage. Finally, we provide a table of lower confidence intervals for Rosenthal's estimator.
Publication Bias in Meta-Analysis: Confidence Intervals for Rosenthal's Fail-Safe Number
Fragkos, Konstantinos C.; Tsagris, Michail; Frangos, Christos C.
2014-01-01
The purpose of the present paper is to assess the efficacy of confidence intervals for Rosenthal's fail-safe number. Although Rosenthal's estimator is highly used by researchers, its statistical properties are largely unexplored. First of all, we developed statistical theory which allowed us to produce confidence intervals for Rosenthal's fail-safe number. This was produced by discerning whether the number of studies analysed in a meta-analysis is fixed or random. Each case produces different variance estimators. For a given number of studies and a given distribution, we provided five variance estimators. Confidence intervals are examined with a normal approximation and a nonparametric bootstrap. The accuracy of the different confidence interval estimates was then tested by methods of simulation under different distributional assumptions. The half normal distribution variance estimator has the best probability coverage. Finally, we provide a table of lower confidence intervals for Rosenthal's estimator. PMID:27437470
Zhang, Zhiyong; Yuan, Ke-Hai
2016-06-01
Cronbach's coefficient alpha is a widely used reliability measure in social, behavioral, and education sciences. It is reported in nearly every study that involves measuring a construct through multiple items. With non-tau-equivalent items, McDonald's omega has been used as a popular alternative to alpha in the literature. Traditional estimation methods for alpha and omega often implicitly assume that data are complete and normally distributed. This study proposes robust procedures to estimate both alpha and omega as well as corresponding standard errors and confidence intervals from samples that may contain potential outlying observations and missing values. The influence of outlying observations and missing data on the estimates of alpha and omega is investigated through two simulation studies. Results show that the newly developed robust method yields substantially improved alpha and omega estimates as well as better coverage rates of confidence intervals than the conventional nonrobust method. An R package coefficientalpha is developed and demonstrated to obtain robust estimates of alpha and omega.
Zhang, Zhiyong; Yuan, Ke-Hai
2015-01-01
Cronbach’s coefficient alpha is a widely used reliability measure in social, behavioral, and education sciences. It is reported in nearly every study that involves measuring a construct through multiple items. With non-tau-equivalent items, McDonald’s omega has been used as a popular alternative to alpha in the literature. Traditional estimation methods for alpha and omega often implicitly assume that data are complete and normally distributed. This study proposes robust procedures to estimate both alpha and omega as well as corresponding standard errors and confidence intervals from samples that may contain potential outlying observations and missing values. The influence of outlying observations and missing data on the estimates of alpha and omega is investigated through two simulation studies. Results show that the newly developed robust method yields substantially improved alpha and omega estimates as well as better coverage rates of confidence intervals than the conventional nonrobust method. An R package coefficientalpha is developed and demonstrated to obtain robust estimates of alpha and omega. PMID:29795870
Peritoneal Dialysis Access Revision in Children: Causes, Interventions, and Outcomes.
Borzych-Duzalka, Dagmara; Aki, T Fazil; Azocar, Marta; White, Colin; Harvey, Elizabeth; Mir, Sevgi; Adragna, Marta; Serdaroglu, Erkin; Sinha, Rajiv; Samaille, Charlotte; Vanegas, Juan Jose; Kari, Jameela; Barbosa, Lorena; Bagga, Arvind; Galanti, Monica; Yavascan, Onder; Leozappa, Giovanna; Szczepanska, Maria; Vondrak, Karel; Tse, Kei-Chiu; Schaefer, Franz; Warady, Bradley A
2017-01-06
Little published information is available about access failure in children undergoing chronic peritoneal dialysis. Our objectives were to evaluate frequency, risk factors, interventions, and outcome of peritoneal dialysis access revision. Data were derived from 824 incident and 1629 prevalent patients from 105 pediatric nephrology centers enrolled in the International Pediatric Peritoneal Dialysis Network Registry between 2007 and 2015. In total, 452 access revisions were recorded in 321 (13%) of 2453 patients over 3134 patient-years of follow-up, resulting in an overall access revision rate of 0.14 per treatment year. Among 824 incident patients, 186 (22.6%) underwent 188 access revisions over 1066 patient-years, yielding an access revision rate of 0.17 per treatment year; 83% of access revisions in incident patients were reported within the first year of peritoneal dialysis treatment. Catheter survival rates in incident patients were 84%, 80%, 77%, and 73% at 12, 24, 36, and 48 months, respectively. By multivariate logistic regression analysis, risk of access revision was associated with younger age (odds ratio, 0.93; 95% confidence interval, 0.92 to 0.95; P<0.001), diagnosis of congenital anomalies of the kidney and urinary tract (odds ratio, 1.28; 95% confidence interval, 1.03 to 1.59; P=0.02), coexisting ostomies (odds ratio, 1.42; 95% confidence interval, 1.07 to 1.87; P=0.01), presence of swan neck tunnel with curled intraperitoneal portion (odds ratio, 1.30; 95% confidence interval, 1.04 to 1.63; P=0.02), and high gross national income (odds ratio, 1.10; 95% confidence interval, 1.02 to 1.19; P=0.01). Main reasons for access revisions included mechanical malfunction (60%), peritonitis (16%), exit site infection (12%), and leakage (6%). Need for access revision increased the risk of peritoneal dialysis technique failure or death (hazard ratio, 1.35; 95% confidence interval, 1.10 to 1.65; P=0.003). Access dysfunction due to mechanical causes doubled the risk of technique failure compared with infectious causes (hazard ratio, 1.95; 95% confidence interval, 1.20 to 2.30; P=0.03). Peritoneal dialysis catheter revisions are common in pediatric patients on peritoneal dialysis and complicate provision of chronic peritoneal dialysis. Attention to potentially modifiable risk factors by pediatric nephrologists and pediatric surgeons should be encouraged. Copyright © 2016 by the American Society of Nephrology.
Peritoneal Dialysis Access Revision in Children: Causes, Interventions, and Outcomes
Aki, T. Fazil; Azocar, Marta; White, Colin; Harvey, Elizabeth; Mir, Sevgi; Adragna, Marta; Serdaroglu, Erkin; Sinha, Rajiv; Samaille, Charlotte; Vanegas, Juan Jose; Kari, Jameela; Barbosa, Lorena; Bagga, Arvind; Galanti, Monica; Yavascan, Onder; Leozappa, Giovanna; Szczepanska, Maria; Vondrak, Karel; Tse, Kei-Chiu; Schaefer, Franz; Warady, Bradley A.
2017-01-01
Background and objectives Little published information is available about access failure in children undergoing chronic peritoneal dialysis. Our objectives were to evaluate frequency, risk factors, interventions, and outcome of peritoneal dialysis access revision. Design, setting, participants, & measurements Data were derived from 824 incident and 1629 prevalent patients from 105 pediatric nephrology centers enrolled in the International Pediatric Peritoneal Dialysis Network Registry between 2007 and 2015. Results In total, 452 access revisions were recorded in 321 (13%) of 2453 patients over 3134 patient-years of follow-up, resulting in an overall access revision rate of 0.14 per treatment year. Among 824 incident patients, 186 (22.6%) underwent 188 access revisions over 1066 patient-years, yielding an access revision rate of 0.17 per treatment year; 83% of access revisions in incident patients were reported within the first year of peritoneal dialysis treatment. Catheter survival rates in incident patients were 84%, 80%, 77%, and 73% at 12, 24, 36, and 48 months, respectively. By multivariate logistic regression analysis, risk of access revision was associated with younger age (odds ratio, 0.93; 95% confidence interval, 0.92 to 0.95; P<0.001), diagnosis of congenital anomalies of the kidney and urinary tract (odds ratio, 1.28; 95% confidence interval, 1.03 to 1.59; P=0.02), coexisting ostomies (odds ratio, 1.42; 95% confidence interval, 1.07 to 1.87; P=0.01), presence of swan neck tunnel with curled intraperitoneal portion (odds ratio, 1.30; 95% confidence interval, 1.04 to 1.63; P=0.02), and high gross national income (odds ratio, 1.10; 95% confidence interval, 1.02 to 1.19; P=0.01). Main reasons for access revisions included mechanical malfunction (60%), peritonitis (16%), exit site infection (12%), and leakage (6%). Need for access revision increased the risk of peritoneal dialysis technique failure or death (hazard ratio, 1.35; 95% confidence interval, 1.10 to 1.65; P=0.003). Access dysfunction due to mechanical causes doubled the risk of technique failure compared with infectious causes (hazard ratio, 1.95; 95% confidence interval, 1.20 to 2.30; P=0.03). Conclusions Peritoneal dialysis catheter revisions are common in pediatric patients on peritoneal dialysis and complicate provision of chronic peritoneal dialysis. Attention to potentially modifiable risk factors by pediatric nephrologists and pediatric surgeons should be encouraged. PMID:27899416
Peng, Tiffany Y; Ehrlich, Samantha F; Crites, Yvonne; Kitzmiller, John L; Kuzniewicz, Michael W; Hedderson, Monique M; Ferrara, Assiamira
2017-02-01
Despite concern for adverse perinatal outcomes in women with diabetes mellitus before pregnancy, recent data on the prevalence of pregestational type 1 and type 2 diabetes mellitus in the United States are lacking. The purpose of this study was to estimate changes in the prevalence of overall pregestational diabetes mellitus (all types) and pregestational type 1 and type 2 diabetes mellitus and to estimate whether changes varied by race-ethnicity from 1996-2014. We conducted a cohort study among 655,428 pregnancies at a Northern California integrated health delivery system from 1996-2014. Logistic regression analyses provided estimates of prevalence and trends. The age-adjusted prevalence (per 100 deliveries) of overall pregestational diabetes mellitus increased from 1996-1999 to 2012-2014 (from 0.58 [95% confidence interval, 0.54-0.63] to 1.06 [95% confidence interval, 1.00-1.12]; P trend <.0001). Significant increases occurred in all racial-ethnic groups; the largest relative increase was among Hispanic women (121.8% [95% confidence interval, 84.4-166.7]); the smallest relative increase was among non-Hispanic white women (49.6% [95% confidence interval, 27.5-75.4]). The age-adjusted prevalence of pregestational type 1 and type 2 diabetes mellitus increased from 0.14 (95% confidence interval, 0.12-0.16) to 0.23 (95% confidence interval, 0.21-0.27; P trend <.0001) and from 0.42 (95% confidence interval, 0.38-0.46) to 0.78 (95% confidence interval, 0.73-0.83; P trend <.0001), respectively. The greatest relative increase in the prevalence of type 1 diabetes mellitus was in non-Hispanic white women (118.4% [95% confidence interval, 70.0-180.5]), who had the lowest increases in the prevalence of type 2 diabetes mellitus (13.6% [95% confidence interval, -8.0 to 40.1]). The greatest relative increase in the prevalence of type 2 diabetes mellitus was in Hispanic women (125.2% [95% confidence interval, 84.8-174.4]), followed by African American women (102.0% [95% confidence interval, 38.3-194.3]) and Asian women (93.3% [95% confidence interval, 48.9-150.9]). The prevalence of overall pregestational diabetes mellitus and pregestational type 1 and type 2 diabetes mellitus increased from 1996-1999 to 2012-2014 and racial-ethnic disparities were observed, possibly because of differing prevalence of maternal obesity. Targeted prevention efforts, preconception care, and disease management strategies are needed to reduce the burden of diabetes mellitus and its sequelae. Copyright © 2016 Elsevier Inc. All rights reserved.
Quantifying uncertainty on sediment loads using bootstrap confidence intervals
NASA Astrophysics Data System (ADS)
Slaets, Johanna I. F.; Piepho, Hans-Peter; Schmitter, Petra; Hilger, Thomas; Cadisch, Georg
2017-01-01
Load estimates are more informative than constituent concentrations alone, as they allow quantification of on- and off-site impacts of environmental processes concerning pollutants, nutrients and sediment, such as soil fertility loss, reservoir sedimentation and irrigation channel siltation. While statistical models used to predict constituent concentrations have been developed considerably over the last few years, measures of uncertainty on constituent loads are rarely reported. Loads are the product of two predictions, constituent concentration and discharge, integrated over a time period, which does not make it straightforward to produce a standard error or a confidence interval. In this paper, a linear mixed model is used to estimate sediment concentrations. A bootstrap method is then developed that accounts for the uncertainty in the concentration and discharge predictions, allowing temporal correlation in the constituent data, and can be used when data transformations are required. The method was tested for a small watershed in Northwest Vietnam for the period 2010-2011. The results showed that confidence intervals were asymmetric, with the highest uncertainty in the upper limit, and that a load of 6262 Mg year-1 had a 95 % confidence interval of (4331, 12 267) in 2010 and a load of 5543 Mg an interval of (3593, 8975) in 2011. Additionally, the approach demonstrated that direct estimates from the data were biased downwards compared to bootstrap median estimates. These results imply that constituent loads predicted from regression-type water quality models could frequently be underestimating sediment yields and their environmental impact.
Kwong, Wilson; Tomlinson, George; Feig, Denice S
2018-02-15
Obesity during pregnancy is associated with a number of adverse obstetric outcomes that include gestational diabetes mellitus, macrosomia, and preeclampsia. Increasing evidence shows that bariatric surgery may decrease the risk of these outcomes. Our aim was to evaluate the benefits and risks of bariatric surgery in obese women according to obstetric outcomes. We performed a systematic literature search using MEDLINE, Embase, Cochrane, Web of Science, and PubMed from inception up to December 12, 2016. Studies were included if they evaluated patients who underwent bariatric surgery, reported subsequent pregnancy outcomes, and compared these outcomes with a control group. Two reviewers extracted study outcomes independently, and risk of bias was assessed with the use of the Newcastle-Ottawa Quality Assessment Scale. Pooled odds ratios for each outcome were estimated with the Dersimonian and Laird random effects model. After a review of 2616 abstracts, 20 cohort studies and approximately 2.8 million subjects (8364 of whom had bariatric surgery) were included in the metaanalysis. In our primary analysis, patients who underwent bariatric surgery showed reduced rates of gestational diabetes mellitus (odds ratio, 0.20; 95% confidence interval, 0.11-0.37, number needed to benefit, 5), large-for-gestational-age infants (odds ratio, 0.31; 95% confidence interval, 0.17-0.59; number needed to benefit, 6), gestational hypertension (odds ratio, 0.38; 95% confidence interval, 0.19-0.76; number needed to benefit, 11), all hypertensive disorders (odds ratio, 0.38; 95% confidence interval, 0.27-0.53; number needed to benefit, 8), postpartum hemorrhage (odds ratio, 0.32; 95% confidence interval, 0.08-1.37; number needed to benefit, 21), and caesarean delivery rates (odds ratio, 0.50; 95% confidence interval, 0.38-0.67; number needed to benefit, 9); however, group of patients showed an increase in small-for-gestational-age infants (odds ratio, 2.16; 95% confidence interval, 1.34-3.48; number needed to harm, 21), intrauterine growth restriction (odds ratio, 2.16; 95% confidence interval, 1.34-3.48; number needed to harm, 66), and preterm deliveries (odds ratio, 1.35; 95% confidence interval, 1.02-1.79; number needed to harm, 35) when compared with control subjects who were matched for presurgery body mass index. There were no differences in rates of preeclampsia, neonatal intensive care unit admissions, stillbirths, malformations, and neonatal death. Malabsorptive surgeries resulted in a greater increase in small-for-gestational-age infants (P=.0466) and a greater decrease in large-for-gestational-age infants (P=<.0001) compared with restrictive surgeries. There were no differences in outcomes when we used administrative databases vs clinical charts. Although bariatric surgery is associated with a reduction in the risk of several adverse obstetric outcomes, there is a potential for an increased risk of other important outcomes that should be considered when bariatric surgery is discussed with reproductive-age women. Copyright © 2018 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Olafsdottir, Kristin B.; Mudelsee, Manfred
2013-04-01
Estimation of the Pearson's correlation coefficient between two time series to evaluate the influences of one time depended variable on another is one of the most often used statistical method in climate sciences. Various methods are used to estimate confidence interval to support the correlation point estimate. Many of them make strong mathematical assumptions regarding distributional shape and serial correlation, which are rarely met. More robust statistical methods are needed to increase the accuracy of the confidence intervals. Bootstrap confidence intervals are estimated in the Fortran 90 program PearsonT (Mudelsee, 2003), where the main intention was to get an accurate confidence interval for correlation coefficient between two time series by taking the serial dependence of the process that generated the data into account. However, Monte Carlo experiments show that the coverage accuracy for smaller data sizes can be improved. Here we adapt the PearsonT program into a new version called PearsonT3, by calibrating the confidence interval to increase the coverage accuracy. Calibration is a bootstrap resampling technique, which basically performs a second bootstrap loop or resamples from the bootstrap resamples. It offers, like the non-calibrated bootstrap confidence intervals, robustness against the data distribution. Pairwise moving block bootstrap is used to preserve the serial correlation of both time series. The calibration is applied to standard error based bootstrap Student's t confidence intervals. The performances of the calibrated confidence intervals are examined with Monte Carlo simulations, and compared with the performances of confidence intervals without calibration, that is, PearsonT. The coverage accuracy is evidently better for the calibrated confidence intervals where the coverage error is acceptably small (i.e., within a few percentage points) already for data sizes as small as 20. One form of climate time series is output from numerical models which simulate the climate system. The method is applied to model data from the high resolution ocean model, INALT01 where the relationship between the Agulhas Leakage and the North Brazil Current is evaluated. Preliminary results show significant correlation between the two variables when there is 10 year lag between them, which is more or less the time that takes the Agulhas Leakage water to reach the North Brazil Current. Mudelsee, M., 2003. Estimating Pearson's correlation coefficient with bootstrap confidence interval from serially dependent time series. Mathematical Geology 35, 651-665.
Strom, Jordan B; McCabe, James M; Waldo, Stephen W; Pinto, Duane S; Kennedy, Kevin F; Feldman, Dmitriy N; Yeh, Robert W
2017-05-01
In 2010, New York State began excluding selected patients with cardiac arrest and coma from publicly reported mortality statistics after percutaneous coronary intervention. We evaluated the effects of this exclusion on rates of coronary angiography, revascularization, and mortality among patients with acute myocardial infarction and cardiac arrest. Using statewide hospitalization files, we identified discharges for acute myocardial infarction and cardiac arrest January 2003 to December 2013 in New York and several comparator states. A difference-in-differences approach was used to evaluate the likelihood of coronary angiography, revascularization, and in-hospital mortality before and after 2010. A total of 26 379 patients with acute myocardial infarction and cardiac arrest (5619 in New York) were included. Of these, 17 141 (65%) underwent coronary angiography, 12 183 (46.2%) underwent percutaneous coronary intervention, and 2832 (10.7%) underwent coronary artery bypass grafting. Before 2010, patients with cardiac arrest in New York were less likely to undergo percutaneous coronary intervention compared with referent states (adjusted relative risk, 0.79; 95% confidence interval, 0.73-0.85; P <0.001). This relationship was unchanged after the policy change (adjusted relative risk, 0.82; 95% confidence interval, 0.76-0.89; interaction P =0.359). Adjusted risks of in-hospital mortality between New York and comparator states after 2010 were also similar (adjusted relative risk, 0.94; 95% confidence interval, 0.87-1.02; P =0.152 for post- versus pre-2010 in New York; adjusted relative risk, 0.88; 95% confidence interval, 0.84-0.92; P <0.001 for comparator states; interaction P =0.103). Exclusion of selected cardiac arrest cases from public reporting was not associated with changes in rates of percutaneous coronary intervention or in-hospital mortality in New York. Rates of revascularization in New York for cardiac arrest patients were lower throughout. © 2017 American Heart Association, Inc.
Fluconazole use and birth defects in the National Birth Defects Prevention Study.
Howley, Meredith M; Carter, Tonia C; Browne, Marilyn L; Romitti, Paul A; Cunniff, Christopher M; Druschel, Charlotte M
2016-05-01
Low-dose fluconazole is used commonly to treat vulvovaginal candidiasis, a condition occurring frequently during pregnancy. Conflicting information exists on the association between low-dose fluconazole use among pregnant women and the risk of major birth defects. We used data from the National Birth Defects Prevention Study to examine this association. The National Birth Defects Prevention Study is a multisite, population-based, case-control study that includes pregnancies with estimated delivery dates from 1997 to 2011. Information on fluconazole use in early pregnancy was collected by self-report from 31,645 mothers of birth defect cases and 11,612 mothers of unaffected controls. Adjusted odds ratios and 95% confidence intervals were estimated for birth defects with 5 or more exposed cases; crude odds ratios and exact 95% confidence intervals were estimated for birth defects with 3-4 exposed cases. Of the 43,257 mothers analyzed, 44 case mothers and 6 control mothers reported using fluconazole. Six exposed infants had cleft lip with cleft palate, 4 had an atrial septal defect, and each of the following defects had 3 exposed cases: hypospadias, tetralogy of Fallot, d-transposition of the great arteries, and pulmonary valve stenosis. Fluconazole use was associated with cleft lip with cleft palate (odds ratio = 5.53; confidence interval = 1.68-18.24) and d-transposition of the great arteries (odds ratio = 7.56; confidence interval = 1.22-35.45). The associations between fluconazole and both cleft lip with cleft palate and d-transposition of the great arteries are consistent with earlier published case reports but not recent epidemiologic studies. Despite the larger sample size of the National Birth Defects Prevention Study, fluconazole use was rare. Further investigation is needed in large studies, with particular emphasis on oral clefts and conotruncal heart defects. Copyright © 2016 Elsevier Inc. All rights reserved.
Associations of High-Grade Glioma With Glioma Risk Alleles and Histories of Allergy and Smoking
Lachance, Daniel H.; Yang, Ping; Johnson, Derek R.; Decker, Paul A.; Kollmeyer, Thomas M.; McCoy, Lucie S.; Rice, Terri; Xiao, Yuanyuan; Ali-Osman, Francis; Wang, Frances; Stoddard, Shawn M.; Sprau, Debra J.; Kosel, Matthew L.; Wiencke, John K.; Wiemels, Joseph L.; Patoka, Joseph S.; Davis, Faith; McCarthy, Bridget; Rynearson, Amanda L.; Worra, Joel B.; Fridley, Brooke L.; O’Neill, Brian Patrick; Buckner, Jan C.; Il’yasova, Dora; Jenkins, Robert B.; Wrensch, Margaret R.
2011-01-01
Glioma risk has consistently been inversely associated with allergy history but not with smoking history despite putative biologic plausibility. Data from 855 high-grade glioma cases and 1,160 controls from 4 geographic regions of the United States during 1997–2008 were analyzed for interactions between allergy and smoking histories and inherited variants in 5 established glioma risk regions: 5p15.3 (TERT), 8q24.21 (CCDC26/MLZE), 9p21.3 (CDKN2B), 11q23.3 (PHLDB1/DDX6), and 20q13.3 (RTEL1). The inverse relation between allergy and glioma was stronger among those who did not (odds ratioallergy-glioma = 0.40, 95% confidence interval: 0.28, 0.58) versus those who did (odds ratioallergy-glioma = 0.76, 95% confidence interval: 0.59, 0.97; Pinteraction = 0.02) carry the 9p21.3 risk allele. However, the inverse association with allergy was stronger among those who carried (odds ratioallergy-glioma = 0.44, 95% confidence interval: 0.29, 0.68) versus those who did not carry (odds ratioallergy-glioma = 0.68, 95% confidence interval: 0.54, 0.86) the 20q13.3 glioma risk allele, but this interaction was not statistically significant (P = 0.14). No relation was observed between glioma risk and smoking (odds ratio = 0.92, 95% confidence interval: 0.77, 1.10; P = 0.37), and there were no interactions for glioma risk of smoking history with any of the risk alleles. The authors’ observations are consistent with a recent report that the inherited glioma risk variants in chromosome regions 9p21.3 and 20q13.3 may modify the inverse association of allergy and glioma. PMID:21742680
O'Neill, D G; Case, J; Boag, A K; Church, D B; McGreevy, P D; Thomson, P C; Brodbelt, D C
2017-11-01
To report prevalence, risk factors and clinical outcomes for presumptive gastric dilation-volvulus diagnosed among an emergency-care population of UK dogs. The study used a cross-sectional design using emergency-care veterinary clinical records from the VetCompass Programme spanning September 1, 2012 to February 28, 2014 and risk factor analysis using multivariable logistic regression modelling. The study population comprised 77,088 dogs attending 50 Vets Now clinics. Overall, 492 dogs had presumptive gastric dilation-volvulus diagnoses, giving a prevalence of 0·64% (95% Confidence interval: 0·58 to 0·70%). Compared with cross-bred dogs, breeds with the highest odds ratios for the diagnosis of presumptive gastric dilation-volvulus were the great Dane (odds ratio: 114·3, 95% Confidence interval 55·1 to 237·1, P<0·001), akita (odds ratio: 84·4, 95% Confidence interval 33·6 to 211·9, P<0·001) and dogue de Bordeaux (odds ratio: 82·9, 95% Confidence interval 39·0 to 176·3, P<0·001). Odds increased as dogs aged up to 12 years and neutered male dogs had 1·3 (95% Confidence interval 1·0 to 1·8, P=0·041) times the odds compared with entire females. Of the cases that were presented alive, 49·7% survived to discharge overall, but 79·3% of surgical cases survived to discharge. Approximately 80% of surgically managed cases survived to discharge. Certain large breeds were highly predisposed. © 2017 British Small Animal Veterinary Association.
Dietary Pattern and Risk of Hodgkin Lymphoma in a Population-Based Case-Control Study
Epstein, Mara M.; Chang, Ellen T.; Zhang, Yawei; Fung, Teresa T.; Batista, Julie L.; Ambinder, Richard F.; Zheng, Tongzhang; Mueller, Nancy E.; Birmann, Brenda M.
2015-01-01
Classic Hodgkin lymphoma (cHL) has few known modifiable risk factors, and the relationship between diet and cHL risk is unclear. We performed the first investigation of an association between dietary pattern and cHL risk in 435 cHL cases and 563 population-based controls from Massachusetts and Connecticut (1997–2000) who completed baseline diet questionnaires. We identified 4 major dietary patterns (“vegetable,” “high meat,” “fruit/low-fat dairy,” “desserts/sweets”) using principal components analysis. We computed multivariable odds ratios and 95% confidence intervals for associations of dietary pattern score (quartiles) with younger-adult (age <50 years), older-adult (age ≥50 years), and overall cHL risk. Secondary analyses examined associations by histological subtype and tumor Epstein-Barr virus (EBV) status. A diet high in desserts/sweets was associated with younger-adult (odds ratio(quartile 4 vs. quartile 1) = 1.60, 95% confidence interval: 1.05, 2.45; Ptrend = 0.008) and EBV-negative, younger-adult (odds ratio = 2.11, 95% confidence interval: 1.31, 3.41; Ptrend = 0.007) cHL risk. A high meat diet was associated with older-adult (odds ratio = 3.34, 95% confidence interval: 1.02, 10.91; Ptrend = 0.04) and EBV-negative, older-adult (odds ratio = 4.64, 95% confidence interval: 1.03, 20.86; Ptrend = 0.04) cHL risk. Other dietary patterns were not clearly associated with cHL. We report the first evidence for a role of dietary pattern in cHL etiology. Diets featuring high intake of meat or desserts and sweets may increase cHL risk. PMID:26182945
Dietary pattern and risk of hodgkin lymphoma in a population-based case-control study.
Epstein, Mara M; Chang, Ellen T; Zhang, Yawei; Fung, Teresa T; Batista, Julie L; Ambinder, Richard F; Zheng, Tongzhang; Mueller, Nancy E; Birmann, Brenda M
2015-09-01
Classic Hodgkin lymphoma (cHL) has few known modifiable risk factors, and the relationship between diet and cHL risk is unclear. We performed the first investigation of an association between dietary pattern and cHL risk in 435 cHL cases and 563 population-based controls from Massachusetts and Connecticut (1997-2000) who completed baseline diet questionnaires. We identified 4 major dietary patterns ("vegetable," "high meat," "fruit/low-fat dairy," "desserts/sweets") using principal components analysis. We computed multivariable odds ratios and 95% confidence intervals for associations of dietary pattern score (quartiles) with younger-adult (age <50 years), older-adult (age ≥50 years), and overall cHL risk. Secondary analyses examined associations by histological subtype and tumor Epstein-Barr virus (EBV) status. A diet high in desserts/sweets was associated with younger-adult (odds ratio(quartile 4 vs. quartile 1) = 1.60, 95% confidence interval: 1.05, 2.45; Ptrend = 0.008) and EBV-negative, younger-adult (odds ratio = 2.11, 95% confidence interval: 1.31, 3.41; Ptrend = 0.007) cHL risk. A high meat diet was associated with older-adult (odds ratio = 3.34, 95% confidence interval: 1.02, 10.91; Ptrend = 0.04) and EBV-negative, older-adult (odds ratio = 4.64, 95% confidence interval: 1.03, 20.86; Ptrend = 0.04) cHL risk. Other dietary patterns were not clearly associated with cHL. We report the first evidence for a role of dietary pattern in cHL etiology. Diets featuring high intake of meat or desserts and sweets may increase cHL risk. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.
Jasim, Sina; Alahdab, Fares; Ahmed, Ahmed T; Tamhane, Shrikant U; Sharma, Anu; Donegan, Diane; Nippoldt, Todd B; Murad, M Hassan
2017-05-01
Growth hormone replacement therapy has benefits for patients with hypopituitarism. The safety profile in regard to tumor recurrence or progression, development of secondary malignancies, or cerebrovascular stroke is still an area of debate. A comprehensive search of multiple databases-MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus was conducted through August 2015. Eligible studies that evaluated long-term adverse events in adult patients with hypopituitarism treated with growth hormone replacement therapy and reported development of pituitary tumor recurrence or progression, secondary malignancies, or cerebrovascular stroke were selected following a predefined protocol. Reviewers, independently and in duplicate, extracted data and assessed the risk of bias. Random-effects meta-analysis was used to pool relative risks and 95 % confidence intervals. We included 15 studies (published 1995-2015) that reported on 46,148 patients. Compared to non-replacement, growth hormone replacement therapy in adults with hypopituitarism was not associated with statistically significant change in pituitary tumor progression or recurrence (relative risk, 0.77; 95 % confidence interval, 0.53-1.13) or development of secondary malignancy (relative risk, 0.99; 95 % confidence interval, 0.70-1.39). In two retrospective studies, there was higher risk of stroke in patients who did not receive replacement (relative risk, 2.07; 95 % confidence interval, 1.51-2.83). The quality of evidence is low due to study limitations and imprecision. This systematic review and meta-analysis supports the overall safety of growth hormone therapeutic use in adults with hypopituitarism with no clear evidence of increased risk of pituitary tumor recurrence, malignancy, or stroke.
Leng, Yue; Wainwright, Nick W. J.; Cappuccio, Francesco P.; Surtees, Paul G.; Hayat, Shabina; Luben, Robert; Brayne, Carol; Khaw, Kay-Tee
2014-01-01
Epidemiologic studies have reported conflicting results on the relationship between daytime napping and mortality risk, and there are few data on the potential association in the British population. We investigated the associations between daytime napping and all-cause or cause-specific mortality in the European Prospective Investigation Into Cancer-Norfolk study, a British population-based cohort study. Among the 16,374 men and women who answered questions on napping habits between 1998 and 2000, a total of 3,251 died during the 13-year follow-up. Daytime napping was associated with an increased risk of all-cause mortality (for napping less than 1 hour per day on average, hazard ratio = 1.14, 95% confidence interval: 1.02, 1.27; for napping 1 hour or longer per day on average, hazard ratio = 1.32, 95% confidence interval: 1.04, 1.68), independent of age, sex, social class, educational level, marital status, employment status, body mass index, physical activity level, smoking status, alcohol intake, depression, self-reported general health, use of hypnotic drugs or other medications, time spent in bed at night, and presence of preexisting health conditions. This association was more pronounced for death from respiratory diseases (for napping less than 1 hour, hazard ratio = 1.40, 95% confidence interval: 0.95, 2.05; for napping 1 hour or more, hazard ratio = 2.56, 95% confidence interval: 1.34, 4.86) and in individuals 65 years of age or younger. Excessive daytime napping might be a useful marker of underlying health risk, particularly of respiratory problems, especially among those 65 years of age or younger. Further research is required to clarify the nature of the observed association. PMID:24685532
Leng, Yue; Wainwright, Nick W J; Cappuccio, Francesco P; Surtees, Paul G; Hayat, Shabina; Luben, Robert; Brayne, Carol; Khaw, Kay-Tee
2014-05-01
Epidemiologic studies have reported conflicting results on the relationship between daytime napping and mortality risk, and there are few data on the potential association in the British population. We investigated the associations between daytime napping and all-cause or cause-specific mortality in the European Prospective Investigation Into Cancer-Norfolk study, a British population-based cohort study. Among the 16,374 men and women who answered questions on napping habits between 1998 and 2000, a total of 3,251 died during the 13-year follow-up. Daytime napping was associated with an increased risk of all-cause mortality (for napping less than 1 hour per day on average, hazard ratio = 1.14, 95% confidence interval: 1.02, 1.27; for napping 1 hour or longer per day on average, hazard ratio = 1.32, 95% confidence interval: 1.04, 1.68), independent of age, sex, social class, educational level, marital status, employment status, body mass index, physical activity level, smoking status, alcohol intake, depression, self-reported general health, use of hypnotic drugs or other medications, time spent in bed at night, and presence of preexisting health conditions. This association was more pronounced for death from respiratory diseases (for napping less than 1 hour, hazard ratio = 1.40, 95% confidence interval: 0.95, 2.05; for napping 1 hour or more, hazard ratio = 2.56, 95% confidence interval: 1.34, 4.86) and in individuals 65 years of age or younger. Excessive daytime napping might be a useful marker of underlying health risk, particularly of respiratory problems, especially among those 65 years of age or younger. Further research is required to clarify the nature of the observed association.
Exposure to Violence and Carotid Artery Intima-Media Thickness in Mexican Women.
Flores-Torres, Mario H; Lynch, Rebekka; Lopez-Ridaura, Ruy; Yunes, Elsa; Monge, Adriana; Ortiz-Panozo, Eduardo; Cantu-Brito, Carlos; Hauksdóttir, Arna; Valdimarsdóttir, Unnur; Lajous, Martín
2017-08-17
Violence against women has become a global public health threat. Data on the potential impact of exposure to violence on cardiovascular disease are scarce. We evaluated the association between exposure to violence and subclinical cardiovascular disease in 634 disease-free women from the Mexican Teachers' Cohort who responded to violence-related items from the Life Stressor Checklist and underwent measures of carotid artery intima-media thickness in 2012 and 2013. We defined exposure to violence as having ever been exposed to physical and/or sexual violence. Intima-media thickness was log-transformed, and subclinical carotid atherosclerosis was defined as intima-media thickness ≥0.8 mm or plaque. We used multivariable linear and logistic regression models adjusted for several potential confounders. Mean age was 48.9±4.3 years. Close to 40% of women reported past exposure to violence. The lifetime prevalence of sexual violence was 7.1%, and prevalence of physical violence was 23.5% (7.7% reported both sexual and physical violence). Relative to women with no history of violence, exposure to violence was associated with higher intima-media thickness (adjusted mean percentage difference=2.4%; 95% confidence interval 0.5, 4.3) and subclinical atherosclerosis (adjusted odds ratio=1.60; 95% confidence interval 1.10, 2.32). The association was stronger for exposure to physical violence, especially by mugging or physical assault by a stranger (adjusted mean % difference=4.6%; 95% confidence interval 1.8, 7.5, and odds ratio of subclinical carotid atherosclerosis=2.06; 95% confidence interval 1.22, 3.49). Exposure to violence, and in particular assault by a stranger, was strongly associated with subclinical cardiovascular disease in Mexican middle-aged women. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.
Adverse childhood experiences and risk of type 2 diabetes: A systematic review and meta-analysis.
Huang, Hao; Yan, Peipei; Shan, Zhilei; Chen, Sijing; Li, Moying; Luo, Cheng; Gao, Hui; Hao, Liping; Liu, Liegang
2015-11-01
It is evident that adverse childhood experiences (ACEs) can influence health status of adult life, but few large-scale studies have assessed the relation of ACEs with type 2 diabetes. This meta-analysis aimed to summarize existing evidence on the link between ACEs and type 2 diabetes in adults. We searched all published studies from PubMed and EMBASE before Aug 2015 using keywords like adverse childhood experiences and diabetes, and scanned references of relevant original articles. We included studies that reported risk estimates for diabetes by ACEs and matched our inclusion criteria. We examined the overall relationship between ACEs and diabetes, and stratified the analyses by type of childhood adversities, study design and outcome measures, respectively. Seven articles fulfilled the inclusion criteria for this Meta-analysis, comprising 4 cohort and 3 cross-section studies. A total of 87,251 participants and 5879 incident cases of type 2 diabetes were reported in these studies. The exposure of ACEs was positively associated with the risk of diabetes with a combined odds ratio of 1.32 (95% confidence interval 1.16 to 1.51) in the total participants. The influence of neglect was most prominent (pooled odds ratio 1.92, 95% confidence interval 1.43 to 2.57) while the effect of physical abuse was least strong (pooled odds ratio 1.30, 95% confidence interval 1.19 to 1.42). The pooled odds ratio associated with sexual abuse was 1.39 with the 95% confidence intervals from 1.28 to 1.52. The results support a significant association of adverse childhood experiences with an elevated risk of type 2 diabetes in adulthood. Copyright © 2015 Elsevier Inc. All rights reserved.
Steinberg, Gary K; Kondziolka, Douglas; Wechsler, Lawrence R; Lunsford, L Dade; Coburn, Maria L; Billigen, Julia B; Kim, Anthony S; Johnson, Jeremiah N; Bates, Damien; King, Bill; Case, Casey; McGrogan, Michael; Yankee, Ernest W; Schwartz, Neil E
2016-07-01
Preclinical data suggest that cell-based therapies have the potential to improve stroke outcomes. Eighteen patients with stable, chronic stroke were enrolled in a 2-year, open-label, single-arm study to evaluate the safety and clinical outcomes of surgical transplantation of modified bone marrow-derived mesenchymal stem cells (SB623). All patients in the safety population (N=18) experienced at least 1 treatment-emergent adverse event. Six patients experienced 6 serious treatment-emergent adverse events; 2 were probably or definitely related to surgical procedure; none were related to cell treatment. All serious treatment-emergent adverse events resolved without sequelae. There were no dose-limiting toxicities or deaths. Sixteen patients completed 12 months of follow-up at the time of this analysis. Significant improvement from baseline (mean) was reported for: (1) European Stroke Scale: mean increase 6.88 (95% confidence interval, 3.5-10.3; P<0.001), (2) National Institutes of Health Stroke Scale: mean decrease 2.00 (95% confidence interval, -2.7 to -1.3; P<0.001), (3) Fugl-Meyer total score: mean increase 19.20 (95% confidence interval, 11.4-27.0; P<0.001), and (4) Fugl-Meyer motor function total score: mean increase 11.40 (95% confidence interval, 4.6-18.2; P<0.001). No changes were observed in modified Rankin Scale. The area of magnetic resonance T2 fluid-attenuated inversion recovery signal change in the ipsilateral cortex 1 week after implantation significantly correlated with clinical improvement at 12 months (P<0.001 for European Stroke Scale). In this interim report, SB623 cells were safe and associated with improvement in clinical outcome end points at 12 months. URL: https://www.clinicaltrials.gov. Unique identifier: NCT01287936. © 2016 American Heart Association, Inc.
A step towards understanding the mechanisms of running-related injuries.
Malisoux, Laurent; Nielsen, Rasmus Oestergaard; Urhausen, Axel; Theisen, Daniel
2015-09-01
To investigate the association between training-related characteristics and running-related injury using a new conceptual model for running-related injury generation, focusing on the synergy between training load and previous injuries, short-term running experience or body mass index (> or < 25 kg m(-2)). Prospective cohort study with a 9-month follow-up. The data of two previous studies using the same methodology were revisited. Recreational runners (n = 517) reported information about running training characteristics (weekly distance, frequency, speed), other sport participation and injuries on a dedicated internet platform. Weekly volume (dichotomized into < 2h and ≥ 2 h) and session frequency (dichotomized into < 2 and ≥ 2) were the main exposures because they were considered necessary causes for running-related injury. Non-training-related characteristics were included in Cox regression analyses as effect-measure modifiers. Hazard ratio was the measure of association. The size of effect-measure modification was calculated as the relative excess risk due to interaction. One hundred sixty-seven runners reported a running-related injury. Crude analyses revealed that weekly volume < 2h (hazard ratio = 3.29; 95% confidence intervals = 2.27; 4.79) and weekly session frequency < 2 (hazard ratio = 2.41; 95% confidence intervals = 1.71; 3.42) were associated with increased injury rate. Previous injury was identified as an effect-measure modifier on weekly volume (relative excess risk due to interaction = 4.69; 95% confidence intervals = 1.42; 7.95; p = 0.005) and session frequency (relative excess risk due to interaction = 2.44; 95% confidence intervals = 0.48; 4.39; p = 0.015). A negative synergy was found between body mass index and weekly volume (relative excess risk due to interaction = -2.88; 95% confidence intervals = -5.10; -0.66; p = 0.018). The effect of a runner's training load on running-related injury is influenced by body mass index and previous injury. These results show the importance to distinguish between confounding and effect-measure modification in running-related injury research. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Blood transfusion for preventing primary and secondary stroke in people with sickle cell disease.
Estcourt, Lise J; Fortin, Patricia M; Hopewell, Sally; Trivella, Marialena; Wang, Winfred C
2017-01-17
Sickle cell disease is one of the commonest severe monogenic disorders in the world, due to the inheritance of two abnormal haemoglobin (beta globin) genes. Sickle cell disease can cause severe pain, significant end-organ damage, pulmonary complications, and premature death. Stroke affects around 10% of children with sickle cell anaemia (HbSS). Chronic blood transfusions may reduce the risk of vaso-occlusion and stroke by diluting the proportion of sickled cells in the circulation.This is an update of a Cochrane Review first published in 2002, and last updated in 2013. To assess risks and benefits of chronic blood transfusion regimens in people with sickle cell disease for primary and secondary stroke prevention (excluding silent cerebral infarcts). We searched for relevant trials in the Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Transfusion Evidence Library (from 1980), and ongoing trial databases; all searches current to 04 April 2016.We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register: 25 April 2016. Randomised controlled trials comparing red blood cell transfusions as prophylaxis for stroke in people with sickle cell disease to alternative or standard treatment. There were no restrictions by outcomes examined, language or publication status. Two authors independently assessed trial eligibility and the risk of bias and extracted data. We included five trials (660 participants) published between 1998 and 2016. Four of these trials were terminated early. The vast majority of participants had the haemoglobin (Hb)SS form of sickle cell disease.Three trials compared regular red cell transfusions to standard care in primary prevention of stroke: two in children with no previous long-term transfusions; and one in children and adolescents on long-term transfusion.Two trials compared the drug hydroxyurea (hydroxycarbamide) and phlebotomy to long-term transfusions and iron chelation therapy: one in primary prevention (children); and one in secondary prevention (children and adolescents).The quality of the evidence was very low to moderate across different outcomes according to GRADE methodology. This was due to the trials being at a high risk of bias due to lack of blinding, indirectness and imprecise outcome estimates. Red cell transfusions versus standard care Children with no previous long-term transfusionsLong-term transfusions probably reduce the incidence of clinical stroke in children with a higher risk of stroke (abnormal transcranial doppler velocities or previous history of silent cerebral infarct), risk ratio 0.12 (95% confidence interval 0.03 to 0.49) (two trials, 326 participants), moderate quality evidence.Long-term transfusions may: reduce the incidence of other sickle cell disease-related complications (acute chest syndrome, risk ratio 0.24 (95% confidence interval 0.12 to 0.48)) (two trials, 326 participants); increase quality of life (difference estimate -0.54, 95% confidence interval -0.92 to -0.17) (one trial, 166 participants); but make little or no difference to IQ scores (least square mean: 1.7, standard error 95% confidence interval -1.1 to 4.4) (one trial, 166 participants), low quality evidence.We are very uncertain whether long-term transfusions: reduce the risk of transient ischaemic attacks, Peto odds ratio 0.13 (95% confidence interval 0.01 to 2.11) (two trials, 323 participants); have any effect on all-cause mortality, no deaths reported (two trials, 326 participants); or increase the risk of alloimmunisation, risk ratio 3.16 (95% confidence interval 0.18 to 57.17) (one trial, 121 participants), very low quality evidence. Children and adolescents with previous long-term transfusions (one trial, 79 participants)We are very uncertain whether continuing long-term transfusions reduces the incidence of: stroke, risk ratio 0.22 (95% confidence interval 0.01 to 4.35); or all-cause mortality, Peto odds ratio 8.00 (95% confidence interval 0.16 to 404.12), very low quality evidence.Several review outcomes were only reported in one trial arm (sickle cell disease-related complications, alloimmunisation, transient ischaemic attacks).The trial did not report neurological impairment, or quality of life. Hydroxyurea and phlebotomy versus red cell transfusions and chelationNeither trial reported on neurological impairment, alloimmunisation, or quality of life. Primary prevention, children (one trial, 121 participants)Switching to hydroxyurea and phlebotomy may have little or no effect on liver iron concentrations, mean difference -1.80 mg Fe/g dry-weight liver (95% confidence interval -5.16 to 1.56), low quality evidence.We are very uncertain whether switching to hydroxyurea and phlebotomy has any effect on: risk of stroke (no strokes); all-cause mortality (no deaths); transient ischaemic attacks, risk ratio 1.02 (95% confidence interval 0.21 to 4.84); or other sickle cell disease-related complications (acute chest syndrome, risk ratio 2.03 (95% confidence interval 0.39 to 10.69)), very low quality evidence. Secondary prevention, children and adolescents (one trial, 133 participants)Switching to hydroxyurea and phlebotomy may: increase the risk of sickle cell disease-related serious adverse events, risk ratio 3.10 (95% confidence interval 1.42 to 6.75); but have little or no effect on median liver iron concentrations (hydroxyurea, 17.3 mg Fe/g dry-weight liver (interquartile range 10.0 to 30.6)); transfusion 17.3 mg Fe/g dry-weight liver (interquartile range 8.8 to 30.7), low quality evidence.We are very uncertain whether switching to hydroxyurea and phlebotomy: increases the risk of stroke, risk ratio 14.78 (95% confidence interval 0.86 to 253.66); or has any effect on all-cause mortality, Peto odds ratio 0.98 (95% confidence interval 0.06 to 15.92); or transient ischaemic attacks, risk ratio 0.66 (95% confidence interval 0.25 to 1.74), very low quality evidence. There is no evidence for managing adults, or children who do not have HbSS sickle cell disease.In children who are at higher risk of stroke and have not had previous long-term transfusions, there is moderate quality evidence that long-term red cell transfusions reduce the risk of stroke, and low quality evidence they also reduce the risk of other sickle cell disease-related complications.In primary and secondary prevention of stroke there is low quality evidence that switching to hydroxyurea with phlebotomy has little or no effect on the liver iron concentration.In secondary prevention of stroke there is low-quality evidence that switching to hydroxyurea with phlebotomy increases the risk of sickle cell disease-related events.All other evidence in this review is of very low quality.
Blood transfusion for preventing primary and secondary stroke in people with sickle cell disease
Estcourt, Lise J; Fortin, Patricia M; Hopewell, Sally; Trivella, Marialena; Wang, Winfred C
2017-01-01
Background Sickle cell disease is one of the commonest severe monogenic disorders in the world, due to the inheritance of two abnormal haemoglobin (beta globin) genes. Sickle cell disease can cause severe pain, significant end-organ damage, pulmonary complications, and premature death. Stroke affects around 10% of children with sickle cell anaemia (HbSS). Chronic blood transfusions may reduce the risk of vaso-occlusion and stroke by diluting the proportion of sickled cells in the circulation. This is an update of a Cochrane Review first published in 2002, and last updated in 2013. Objectives To assess risks and benefits of chronic blood transfusion regimens in people with sickle cell disease for primary and secondary stroke prevention (excluding silent cerebral infarcts). Search methods We searched for relevant trials in the Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Transfusion Evidence Library (from 1980), and ongoing trial databases; all searches current to 04 April 2016. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register: 25 April 2016. Selection criteria Randomised controlled trials comparing red blood cell transfusions as prophylaxis for stroke in people with sickle cell disease to alternative or standard treatment. There were no restrictions by outcomes examined, language or publication status. Data collection and analysis Two authors independently assessed trial eligibility and the risk of bias and extracted data. Main results We included five trials (660 participants) published between 1998 and 2016. Four of these trials were terminated early. The vast majority of participants had the haemoglobin (Hb)SS form of sickle cell disease. Three trials compared regular red cell transfusions to standard care in primary prevention of stroke: two in children with no previous long-term transfusions; and one in children and adolescents on long-term transfusion. Two trials compared the drug hydroxyurea (hydroxycarbamide) and phlebotomy to long-term transfusions and iron chelation therapy: one in primary prevention (children); and one in secondary prevention (children and adolescents). The quality of the evidence was very low to moderate across different outcomes according to GRADE methodology. This was due to the trials being at a high risk of bias due to lack of blinding, indirectness and imprecise outcome estimates. Red cell transfusions versus standard care Children with no previous long-term transfusions Long-term transfusions probably reduce the incidence of clinical stroke in children with a higher risk of stroke (abnormal transcranial doppler velocities or previous history of silent cerebral infarct), risk ratio 0.12 (95% confidence interval 0.03 to 0.49) (two trials, 326 participants), moderate quality evidence. Long-term transfusions may: reduce the incidence of other sickle cell disease-related complications (acute chest syndrome, risk ratio 0.24 (95% confidence interval 0.12 to 0.48)) (two trials, 326 participants); increase quality of life (difference estimate -0.54, 95% confidence interval -0.92 to -0.17) (one trial, 166 participants); but make little or no difference to IQ scores (least square mean: 1.7, standard error 95% confidence interval -1.1 to 4.4) (one trial, 166 participants), low quality evidence. We are very uncertain whether long-term transfusions: reduce the risk of transient ischaemic attacks, Peto odds ratio 0.13 (95% confidence interval 0.01 to 2.11) (two trials, 323 participants); have any effect on all-cause mortality, no deaths reported (two trials, 326 participants); or increase the risk of alloimmunisation, risk ratio 3.16 (95% confidence interval 0.18 to 57.17) (one trial, 121 participants), very low quality evidence. Children and adolescents with previous long-term transfusions (one trial, 79 participants) We are very uncertain whether continuing long-term transfusions reduces the incidence of: stroke, risk ratio 0.22 (95% confidence interval 0.01 to 4.35); or all-cause mortality, Peto odds ratio 8.00 (95% confidence interval 0.16 to 404.12), very low quality evidence. Several review outcomes were only reported in one trial arm (sickle cell disease-related complications, alloimmunisation, transient ischaemic attacks). The trial did not report neurological impairment, or quality of life. Hydroxyurea and phlebotomy versus red cell transfusions and chelation Neither trial reported on neurological impairment, alloimmunisation, or quality of life. Primary prevention, children (one trial, 121 participants) Switching to hydroxyurea and phlebotomy may have little or no effect on liver iron concentrations, mean difference -1.80 mg Fe/g dry-weight liver (95% confidence interval -5.16 to 1.56), low quality evidence. We are very uncertain whether switching to hydroxyurea and phlebotomy has any effect on: risk of stroke (no strokes); all-cause mortality (no deaths); transient ischaemic attacks, risk ratio 1.02 (95% confidence interval 0.21 to 4.84); or other sickle cell disease-related complications (acute chest syndrome, risk ratio 2.03 (95% confidence interval 0.39 to 10.69)), very low quality evidence. Secondary prevention, children and adolescents (one trial, 133 participants) Switching to hydroxyurea and phlebotomy may: increase the risk of sickle cell disease-related serious adverse events, risk ratio 3.10 (95% confidence interval 1.42 to 6.75); but have little or no effect on median liver iron concentrations (hydroxyurea, 17.3 mg Fe/g dry-weight liver (interquartile range 10.0 to 30.6)); transfusion 17.3 mg Fe/g dry-weight liver (interquartile range 8.8 to 30.7), low quality evidence. We are very uncertain whether switching to hydroxyurea and phlebotomy: increases the risk of stroke, risk ratio 14.78 (95% confidence interval 0.86 to 253.66); or has any effect on all-cause mortality, Peto odds ratio 0.98 (95% confidence interval 0.06 to 15.92); or transient ischaemic attacks, risk ratio 0.66 (95% confidence interval 0.25 to 1.74), very low quality evidence. Authors’ conclusions There is no evidence for managing adults, or children who do not have HbSS sickle cell disease. In children who are at higher risk of stroke and have not had previous long-term transfusions, there is moderate quality evidence that long-term red cell transfusions reduce the risk of stroke, and low quality evidence they also reduce the risk of other sickle cell disease-related complications. In primary and secondary prevention of stroke there is low quality evidence that switching to hydroxyurea with phlebotomy has little or no effect on the liver iron concentration. In secondary prevention of stroke there is low-quality evidence that switching to hydroxyurea with phlebotomy increases the risk of sickle cell disease-related events. All other evidence in this review is of very low quality. PMID:24226646
Fagerland, Morten W; Sandvik, Leiv; Mowinckel, Petter
2011-04-13
The number of events per individual is a widely reported variable in medical research papers. Such variables are the most common representation of the general variable type called discrete numerical. There is currently no consensus on how to compare and present such variables, and recommendations are lacking. The objective of this paper is to present recommendations for analysis and presentation of results for discrete numerical variables. Two simulation studies were used to investigate the performance of hypothesis tests and confidence interval methods for variables with outcomes {0, 1, 2}, {0, 1, 2, 3}, {0, 1, 2, 3, 4}, and {0, 1, 2, 3, 4, 5}, using the difference between the means as an effect measure. The Welch U test (the T test with adjustment for unequal variances) and its associated confidence interval performed well for almost all situations considered. The Brunner-Munzel test also performed well, except for small sample sizes (10 in each group). The ordinary T test, the Wilcoxon-Mann-Whitney test, the percentile bootstrap interval, and the bootstrap-t interval did not perform satisfactorily. The difference between the means is an appropriate effect measure for comparing two independent discrete numerical variables that has both lower and upper bounds. To analyze this problem, we encourage more frequent use of parametric hypothesis tests and confidence intervals.
Confidence Intervals for Error Rates Observed in Coded Communications Systems
NASA Astrophysics Data System (ADS)
Hamkins, J.
2015-05-01
We present methods to compute confidence intervals for the codeword error rate (CWER) and bit error rate (BER) of a coded communications link. We review several methods to compute exact and approximate confidence intervals for the CWER, and specifically consider the situation in which the true CWER is so low that only a handful, if any, codeword errors are able to be simulated. In doing so, we answer the question of how long an error-free simulation must be run in order to certify that a given CWER requirement is met with a given level of confidence, and discuss the bias introduced by aborting a simulation after observing the first codeword error. Next, we turn to the lesser studied problem of determining confidence intervals for the BER of coded systems. Since bit errors in systems that use coding or higher-order modulation do not occur independently, blind application of a method that assumes independence leads to inappropriately narrow confidence intervals. We present a new method to compute the confidence interval properly, using the first and second sample moments of the number of bit errors per codeword. This is the first method we know of to compute a confidence interval for the BER of a coded or higher-order modulation system.
New-onset diabetes after pancreatoduodenectomy: A systematic review and meta-analysis.
Scholten, Lianne; Mungroop, Timothy H; Haijtink, Simone A L; Issa, Yama; van Rijssen, L Bengt; Koerkamp, Bas Groot; van Eijck, Casper H; Busch, Olivier R; DeVries, J Hans; Besselink, Marc G
2018-05-17
Pancreatoduodenectomy may lead to new-onset diabetes mellitus, also known as type 3c diabetes, but the exact risk of this complication is unknown. The aim of this review was to assess the risk of new-onset diabetes mellitus after pancreatoduodenectomy. A literature search was performed in PubMed, Embase (Ovid), and the Cochrane Library for English articles published from March 1993 until March 2017 (PROSPERO registry number: CRD42016039784). Studies reporting on the risk of new-onset diabetes mellitus after pancreatoduodenectomy were included. For meta-analysis, studies were pooled using the random-effects model. All studies were appraised according to the Newcastle-Ottawa Scale. After screening 1,523 studies, 22 studies involving 1,121 patients were eligible. The mean weighted overall proportion of new-onset diabetes mellitus after pancreatoduodenectomy was 16% (95% confidence interval, 12%-20%). We found no significant difference in risk of new-onset diabetes mellitus when pancreatoduodenectomy was performed for nonmalignant disease after excluding patients with chronic pancreatitis (19% risk; 95% confidence interval, 7%-43%; 6 studies) or for malignant disease (22% risk; 95% confidence interval, 14%-32%; 11 studies), P = .71. Among all patients, 6% (95% confidence interval, 4%-10%) developed insulin-dependent new-onset diabetes mellitus. This systematic review identified a clinically relevant risk of new-onset diabetes mellitus after pancreatoduodenectomy of which patients should be informed preoperatively. Copyright © 2018 Elsevier Inc. All rights reserved.
Daytime Napping, Nighttime Sleeping, and Parkinson Disease
Gao, Jianjun; Huang, Xuemei; Park, Yikyung; Hollenbeck, Albert; Blair, Aaron; Schatzkin, Arthur; Chen, Honglei
2011-01-01
Preliminary evidence suggests that daytime sleepiness may predate clinical diagnosis of Parkinson disease. The authors examined daytime napping and nighttime sleeping durations, reported in 1996–1997 by 220,934 US NIH-AARP Diet and Health Study participants, in relation to Parkinson disease diagnoses at 3 clinical stages: established (cases diagnosed before 1995, n = 267), recent (1995–1999, n = 396), and prediagnostic (2000 and after, n = 770). Odds ratios and 95% confidence intervals were derived from multivariate logistic regression models. Longer daytime napping was associated with higher odds of Parkinson disease at all 3 clinical stages: the odds ratios comparing long nappers (>1 hour/day) with nonnappers were 3.9 (95% confidence interval: 2.8, 5.6) for established cases, 2.2 (95% confidence interval: 1.7, 3.0) for recent cases, and 1.5 (95% confidence interval: 1.2, 1.9) for prediagnostic cases. Further control for health status or nighttime sleeping duration attenuated the association for established cases but made little difference for recent or prediagnostic cases. In the nighttime sleeping analysis, a clear U-shaped association with Parkinson disease was observed for established cases; however, this association was attenuated markedly for recent cases and disappeared for prediagnostic cases. This study supports the notion that daytime sleepiness, but not nighttime sleeping duration, is one of the early nonmotor symptoms of Parkinson disease. PMID:21402730
Asymptotic confidence intervals for the Pearson correlation via skewness and kurtosis.
Bishara, Anthony J; Li, Jiexiang; Nash, Thomas
2018-02-01
When bivariate normality is violated, the default confidence interval of the Pearson correlation can be inaccurate. Two new methods were developed based on the asymptotic sampling distribution of Fisher's z' under the general case where bivariate normality need not be assumed. In Monte Carlo simulations, the most successful of these methods relied on the (Vale & Maurelli, 1983, Psychometrika, 48, 465) family to approximate a distribution via the marginal skewness and kurtosis of the sample data. In Simulation 1, this method provided more accurate confidence intervals of the correlation in non-normal data, at least as compared to no adjustment of the Fisher z' interval, or to adjustment via the sample joint moments. In Simulation 2, this approximate distribution method performed favourably relative to common non-parametric bootstrap methods, but its performance was mixed relative to an observed imposed bootstrap and two other robust methods (PM1 and HC4). No method was completely satisfactory. An advantage of the approximate distribution method, though, is that it can be implemented even without access to raw data if sample skewness and kurtosis are reported, making the method particularly useful for meta-analysis. Supporting information includes R code. © 2017 The British Psychological Society.
Significance testing - are we ready yet to abandon its use?
The, Bertram
2011-11-01
Understanding of the damaging effects of significance testing has steadily grown. Reporting p values without dichotomizing the result to be significant or not, is not the solution. Confidence intervals are better, but are troubled by a non-intuitive interpretation, and are often misused just to see whether the null value lies within the interval. Bayesian statistics provide an alternative which solves most of these problems. Although criticized for relying on subjective models, the interpretation of a Bayesian posterior probability is more intuitive than the interpretation of a p value, and seems to be closest to intuitive patterns of human decision making. Another alternative could be using confidence interval functions (or p value functions) to display a continuum of intervals at different levels of confidence around a point estimate. Thus, better alternatives to significance testing exist. The reluctance to abandon this practice might be both preference of clinging to old habits as well as the unfamiliarity with better methods. Authors might question if using less commonly exercised, though superior, techniques will be well received by the editors, reviewers and the readership. A joint effort will be needed to abandon significance testing in clinical research in the future.
Childhood Abuse and Suicidal Ideation in a Cohort of Pregnant Peruvian Women
ZHONG, Qiu-Yue; WELLS, Anne; RONDON, Marta B.; WILLIAMS, Michelle A.; BARRIOS, Yasmin V.; SANCHEZ, Sixto E.; GELAYE, Bizu
2016-01-01
Background Childhood abuse is a major global and public health problem associated with a myriad of adverse outcomes across the life course. Suicide is one of the leading causes of mortality during the perinatal period. However, few studies have assessed the relationship between experiences of childhood abuse and suicidal ideation in pregnancy. Objective To examine the association between exposure to childhood abuse and suicidal ideation among pregnant women. Study Design A cross-sectional study was conducted among 2,964 pregnant women attending prenatal clinics, in Lima, Peru. Childhood abuse was assessed using the Childhood Physical and Sexual Abuse Questionnaire. Depression and suicidal ideation were assessed using the Patient Health Questionnaire-9 scale. Logistic regression procedures were performed to estimate adjusted odds ratios and 95% confidence intervals adjusted for potential confounders. Results Overall, the prevalence of childhood abuse in this cohort was 71.8% and antepartum suicidal ideation was 15.8%. The prevalence of antepartum suicidal ideation was higher among women who reported experiencing any childhood abuse compared to those reporting none (89.3% vs. 10.7%, P<0.0001). After adjusting for potential confounders, including antepartum depression and lifetime intimate partner violence, those with history of any childhood abuse had a 2.9-fold (adjusted odds ratios; 95% confidence intervals: 2.12-3.97) increased odds of reporting suicidal ideation. Women who experienced both physical and sexual childhood abuse had much higher odds of suicidal ideation (adjusted odds ratios =4.04; 95% confidence intervals: 2.88-5.68). Women who experienced any childhood abuse and reported depression had 3.44-fold (adjusted odds ratios; 95% confidence intervals: 1.84-6.43) increased odds of suicidal ideation compared with depressed women with no history of childhood abuse. Finally, the odds of suicidal ideation increased with increased number of childhood abuse events experienced (P-value for trend<0.001). Conclusion Maternal history of childhood abuse was associated with increased odds of antepartum suicidal ideation. It is important for clinicians to be aware of the potential increased risk of suicidal behaviors among pregnant women with a history of childhood physical and sexual abuse. PMID:27173085
Childhood abuse and suicidal ideation in a cohort of pregnant Peruvian women.
Zhong, Qiu-Yue; Wells, Anne; Rondon, Marta B; Williams, Michelle A; Barrios, Yasmin V; Sanchez, Sixto E; Gelaye, Bizu
2016-10-01
Childhood abuse is a major global and public health problem associated with a myriad of adverse outcomes across the life course. Suicide is one of the leading causes of mortality during the perinatal period. However, few studies have assessed the relationship between experiences of childhood abuse and suicidal ideation in pregnancy. We sought to examine the association between exposure to childhood abuse and suicidal ideation among pregnant women. A cross-sectional study was conducted among 2964 pregnant women attending prenatal clinics in Lima, Peru. Childhood abuse was assessed using the Childhood Physical and Sexual Abuse Questionnaire. Depression and suicidal ideation were assessed using the Patient Health Questionnaire-9 scale. Logistic regression procedures were performed to estimate adjusted odds ratios and 95% confidence intervals adjusted for potential confounders. Overall, the prevalence of childhood abuse in this cohort was 71.8% and antepartum suicidal ideation was 15.8%. The prevalence of antepartum suicidal ideation was higher among women who reported experiencing any childhood abuse compared to those reporting none (89.3% vs 10.7%, P < .0001). After adjusting for potential confounders, including antepartum depression and lifetime intimate partner violence, those with history of any childhood abuse had a 2.9-fold (2.90, adjusted odds ratio; 95% confidence interval, 2.12-3.97) increased odds of reporting suicidal ideation. Women who experienced both physical and sexual childhood abuse had much higher odds of suicidal ideation (adjusted odds ratio, 4.04; 95% confidence interval, 2.88-5.68). Women who experienced any childhood abuse and reported depression had 3.44-fold (3.44, adjusted odds ratio; 95% confidence interval, 1.84-6.43) increased odds of suicidal ideation compared with depressed women with no history of childhood abuse. Finally, the odds of suicidal ideation increased with increased number of childhood abuse events experienced (P value for linear trend < .001). Maternal history of childhood abuse was associated with increased odds of antepartum suicidal ideation. It is important for clinicians to be aware of the potential increased risk of suicidal behaviors among pregnant women with a history of childhood physical and sexual abuse. Copyright © 2016 Elsevier Inc. All rights reserved.
Di Mascio, Daniele; Magro-Malosso, Elena Rita; Saccone, Gabriele; Marhefka, Gregary D; Berghella, Vincenzo
2016-11-01
Preterm birth is the major cause of perinatal mortality in the United States. In the past, pregnant women have been recommended to not exercise because of presumed risks of preterm birth. Physical activity has been theoretically related to preterm birth because it increases the release of catecholamines, especially norepinephrine, which might stimulate myometrial activity. Conversely, exercise may reduce the risk of preterm birth by other mechanisms such as decreased oxidative stress or improved placenta vascularization. Therefore, the safety of exercise regarding preterm birth and its effects on gestational age at delivery remain controversial. The objective of the study was to evaluate the effects of exercise during pregnancy on the risk of preterm birth. MEDLINE, EMBASE, Web of Sciences, Scopus, ClinicalTrial.gov, OVID, and Cochrane Library were searched from the inception of each database to April 2016. Selection criteria included only randomized clinical trials of pregnant women randomized before 23 weeks to an aerobic exercise regimen or not. Types of participants included women of normal weight with uncomplicated, singleton pregnancies without any obstetric contraindication to physical activity. The summary measures were reported as relative risk or as mean difference with 95% confidence intervals. The primary outcome was the incidence of preterm birth <37 weeks. Of the 2059 women included in the meta-analysis, 1022 (49.6%) were randomized to the exercise group and 1037 (50.4%) to the control group. Aerobic exercise lasted about 35-90 minutes 3-4 times per week. Women who were randomized to aerobic exercise had a similar incidence of preterm birth of <37 weeks (4.5% vs 4.4%; relative risk, 1.01, 95% confidence interval, 0.68-1.50) and a similar mean gestational age at delivery (mean difference, 0.05 week, 95% confidence interval, -0.07 to 0.17) compared with controls. Women in the exercise group had a significantly higher incidence of vaginal delivery (73.6% vs 67.5%; relative risk, 1.09, 95% confidence interval, 1.04-1.15) and a significantly lower incidence of cesarean delivery (17.9% vs 22%; relative risk, 0.82, 95% confidence interval, 0.69-0.97) compared with controls. The incidence of operative vaginal delivery (12.9% vs 16.5%; relative risk, 0.78, 95% confidence interval, 0.61-1.01) was similar in both groups. Women in the exercise group had a significantly lower incidence of gestational diabetes mellitus (2.9% vs 5.6%; relative risk, 0.51, 95% confidence interval, 0.31-0.82) and a significantly lower incidence of hypertensive disorders (1.0% vs 5.6%; relative risk, 0.21, 95% confidence interval, 0.09-0.45) compared with controls. No differences in low birthweight (5.2% vs 4.7%; relative risk, 1.11, 95% confidence interval, 0.72-1.73) and mean birthweight (mean difference, -10.46 g, 95% confidence interval, -47.10 to 26.21) between the exercise group and controls were found. Aerobic exercise for 35-90 minutes 3-4 times per week during pregnancy can be safely performed by normal-weight women with singleton, uncomplicated gestations because this is not associated with an increased risk of preterm birth or with a reduction in mean gestational age at delivery. Exercise was associated with a significantly higher incidence of vaginal delivery and a significantly lower incidence of cesarean delivery, with a significantly lower incidence of gestational diabetes mellitus and hypertensive disorders and therefore should be encouraged. Copyright © 2016. Published by Elsevier Inc.
Uncertainty of exploitation estimates made from tag returns
Miranda, L.E.; Brock, R.E.; Dorr, B.S.
2002-01-01
Over 6,000 crappies Pomoxis spp. were tagged in five water bodies to estimate exploitation rates by anglers. Exploitation rates were computed as the percentage of tags returned after adjustment for three sources of uncertainty: postrelease mortality due to the tagging process, tag loss, and the reporting rate of tagged fish. Confidence intervals around exploitation rates were estimated by resampling from the probability distributions of tagging mortality, tag loss, and reporting rate. Estimates of exploitation rates ranged from 17% to 54% among the five study systems. Uncertainty around estimates of tagging mortality, tag loss, and reporting resulted in 90% confidence intervals around the median exploitation rate as narrow as 15 percentage points and as broad as 46 percentage points. The greatest source of estimation error was uncertainty about tag reporting. Because the large investments required by tagging and reward operations produce imprecise estimates of the exploitation rate, it may be worth considering other approaches to estimating it or simply circumventing the exploitation question altogether.
Minimax confidence intervals in geomagnetism
NASA Technical Reports Server (NTRS)
Stark, Philip B.
1992-01-01
The present paper uses theory of Donoho (1989) to find lower bounds on the lengths of optimally short fixed-length confidence intervals (minimax confidence intervals) for Gauss coefficients of the field of degree 1-12 using the heat flow constraint. The bounds on optimal minimax intervals are about 40 percent shorter than Backus' intervals: no procedure for producing fixed-length confidence intervals, linear or nonlinear, can give intervals shorter than about 60 percent the length of Backus' in this problem. While both methods rigorously account for the fact that core field models are infinite-dimensional, the application of the techniques to the geomagnetic problem involves approximations and counterfactual assumptions about the data errors, and so these results are likely to be extremely optimistic estimates of the actual uncertainty in Gauss coefficients.
ERIC Educational Resources Information Center
Strazzeri, Kenneth Charles
2013-01-01
The purposes of this study were to investigate (a) undergraduate students' reasoning about the concepts of confidence intervals (b) undergraduate students' interactions with "well-designed" screencast videos on sampling distributions and confidence intervals, and (c) how screencast videos improve undergraduate students' reasoning ability…
Self-reported bruxism mirrors anxiety and stress in adults.
Ahlberg, Jari; Lobbezoo, Frank; Ahlberg, Kristiina; Manfredini, Daniele; Hublin, Christer; Sinisalo, Juha; Könönen, Mauno; Savolainen, Aslak
2013-01-01
The aims were to analyze whether the levels of self-reported bruxism and anxiety associate among otherwise healthy subjects, and to investigate the independent effects of anxiety and stress experience on the probability of self-reported bruxism. As part of a study on irregular shift work, a questionnaire was mailed to all employees of the Finnish Broadcasting Company with irregular shift work (number of subjects: n=750) and to an equal number of randomly selected employees in the same company with regular eight-hour daytime work. The response rates were 82.3% (56.6 % men) and 34.3 % (46.7 % men), respectively. Among the 874 respondents, those aware of more frequent bruxism reported significantly more severe anxiety (p<0.001). Adjusted by age and gender, frequent bruxers were more than two times more likely to report severe stress (odds ratio 2.5; 95% confidence interval 1.5-4.2) and anxiety (odds ratio 2.2; 95% confidence interval 1.3-3.6) than non-or-mild bruxers. Present findings suggest that self-reported bruxism and psychological states such as anxiety or stress may be related in working age subjects.
Schiff, Melissa A; Cummings, Peter
2004-11-01
To evaluate agreement between police and trained investigators regarding seat belt use by crash victims, according to injury severity. We used data from the National Accident Sampling System Crashworthiness Data System (CDS) for front seat occupants, 16 years and older, in crashes during 1993-2000. Crashworthiness Data System investigators determined belt use from vehicle inspection, interviews, and medical record information; their assessment was considered the gold standard for this analysis. Occupant severity of injury was categorized in five levels from no injuries to death. We estimated the sensitivity, specificity, and area under receiver operating characteristic curves for police reports of belt use. Among 48,858 occupants, sensitivity of a police report that a belt was used was 95.8% overall and varied only modestly by injury severity. Specificity of a police report that a belt was not used was 69.1% overall; it was the lowest among the uninjured (53.2%) and greatest among the dead (90.4%). The area under the curve was 0.82 (95% confidence interval 0.82-0.83) overall; this was lowest among those not injured (0.75, 95% confidence interval 0.74-0.76) and increased with injury severity to 0.91 (95% confidence interval 0.90-0.93) among those who died. Police usually classify belted crash victims as belted, regardless of injury severity. But they often classify unbelted survivors as belted when they were not. This misclassification may result in exaggerated estimates of seat belt effectiveness in some studies.
Improved central confidence intervals for the ratio of Poisson means
NASA Astrophysics Data System (ADS)
Cousins, R. D.
The problem of confidence intervals for the ratio of two unknown Poisson means was "solved" decades ago, but a closer examination reveals that the standard solution is far from optimal from the frequentist point of view. We construct a more powerful set of central confidence intervals, each of which is a (typically proper) subinterval of the corresponding standard interval. They also provide upper and lower confidence limits which are more restrictive than the standard limits. The construction follows Neyman's original prescription, though discreteness of the Poisson distribution and the presence of a nuisance parameter (one of the unknown means) lead to slightly conservative intervals. Philosophically, the issue of the appropriateness of the construction method is similar to the issue of conditioning on the margins in 2×2 contingency tables. From a frequentist point of view, the new set maintains (over) coverage of the unknown true value of the ratio of means at each stated confidence level, even though the new intervals are shorter than the old intervals by any measure (except for two cases where they are identical). As an example, when the number 2 is drawn from each Poisson population, the 90% CL central confidence interval on the ratio of means is (0.169, 5.196), rather than (0.108, 9.245). In the cited literature, such confidence intervals have applications in numerous branches of pure and applied science, including agriculture, wildlife studies, manufacturing, medicine, reliability theory, and elementary particle physics.
CALCULATION OF NONLINEAR CONFIDENCE AND PREDICTION INTERVALS FOR GROUND-WATER FLOW MODELS.
Cooley, Richard L.; Vecchia, Aldo V.
1987-01-01
A method is derived to efficiently compute nonlinear confidence and prediction intervals on any function of parameters derived as output from a mathematical model of a physical system. The method is applied to the problem of obtaining confidence and prediction intervals for manually-calibrated ground-water flow models. To obtain confidence and prediction intervals resulting from uncertainties in parameters, the calibrated model and information on extreme ranges and ordering of the model parameters within one or more independent groups are required. If random errors in the dependent variable are present in addition to uncertainties in parameters, then calculation of prediction intervals also requires information on the extreme range of error expected. A simple Monte Carlo method is used to compute the quantiles necessary to establish probability levels for the confidence and prediction intervals. Application of the method to a hypothetical example showed that inclusion of random errors in the dependent variable in addition to uncertainties in parameters can considerably widen the prediction intervals.
Bootstrapping Confidence Intervals for Robust Measures of Association.
ERIC Educational Resources Information Center
King, Jason E.
A Monte Carlo simulation study was conducted to determine the bootstrap correction formula yielding the most accurate confidence intervals for robust measures of association. Confidence intervals were generated via the percentile, adjusted, BC, and BC(a) bootstrap procedures and applied to the Winsorized, percentage bend, and Pearson correlation…
ERIC Educational Resources Information Center
Tryon, Warren W.; Lewis, Charles
2009-01-01
Tryon presented a graphic inferential confidence interval (ICI) approach to analyzing two independent and dependent means for statistical difference, equivalence, replication, indeterminacy, and trivial difference. Tryon and Lewis corrected the reduction factor used to adjust descriptive confidence intervals (DCIs) to create ICIs and introduced…
Four applications of permutation methods to testing a single-mediator model.
Taylor, Aaron B; MacKinnon, David P
2012-09-01
Four applications of permutation tests to the single-mediator model are described and evaluated in this study. Permutation tests work by rearranging data in many possible ways in order to estimate the sampling distribution for the test statistic. The four applications to mediation evaluated here are the permutation test of ab, the permutation joint significance test, and the noniterative and iterative permutation confidence intervals for ab. A Monte Carlo simulation study was used to compare these four tests with the four best available tests for mediation found in previous research: the joint significance test, the distribution of the product test, and the percentile and bias-corrected bootstrap tests. We compared the different methods on Type I error, power, and confidence interval coverage. The noniterative permutation confidence interval for ab was the best performer among the new methods. It successfully controlled Type I error, had power nearly as good as the most powerful existing methods, and had better coverage than any existing method. The iterative permutation confidence interval for ab had lower power than do some existing methods, but it performed better than any other method in terms of coverage. The permutation confidence interval methods are recommended when estimating a confidence interval is a primary concern. SPSS and SAS macros that estimate these confidence intervals are provided.
Foldes-Busque, Guillaume; Denis, Isabelle; Poitras, Julien; Fleet, Richard P; Archambault, Patrick; Dionne, Clermont E
2017-01-01
This study examined the prevalence of emergency department visits prompted by panic attacks in patients with non-cardiac chest pain. A validated structured telephone interview was used to assess panic attacks and their association with the emergency department consultation in 1327 emergency department patients with non-cardiac chest pain. Patients reported at least one panic attack in the past 6 months in 34.5 per cent (95% confidence interval: 32.0%-37.1%) of cases, and 77.1 per cent (95% confidence interval: 73.0%-80.7%) of patients who reported panic attacks had visited the emergency department with non-cardiac chest pain following a panic attack. These results indicate that panic attacks may explain a significant proportion of emergency department visits for non-cardiac chest pain.
Oldenburg, Catherine E; Biello, Katie B; Perez-Brumer, Amaya G; Rosenberger, Joshua; Novak, David S; Mayer, Kenneth H; Mimiaga, Matthew J
2017-03-01
The objective of this study was to characterize HIV testing practices among men who have sex with men in Mexico and intention to use HIV self-testing. In 2012, members of one of the largest social/sexual networking websites for men who have sex with men in Latin America completed an anonymous online survey. This analysis was restricted to HIV-uninfected men who have sex with men residing in Mexico. Multivariable logistic regression models were fit to assess factors associated with HIV testing and intention to use a HIV self-test. Of 4537 respondents, 70.9% reported ever having a HIV test, of whom 75.5% reported testing at least yearly. The majority (94.3%) indicated that they would use a HIV home self-test if it were available. Participants identifying as bisexual less often reported ever HIV testing compared to those identifying as gay/homosexual (adjusted odds ratio = 0.52, 95% confidence interval: 0.44-0.62). Having a physical exam in the past year was associated with increased ever HIV testing (adjusted odds ratio = 4.35, 95% confidence interval: 3.73-5.07), but associated with decreased interest in HIV self-testing (adjusted odds ratio = 0.66, 95% confidence interval: 0.48-0.89). The high intention to use HIV home self-testing supports the use of this method as an acceptable alternative to clinic- or hospital-based HIV testing.
Viswanath, Kasisomayajula; Ackerson, Leland K.
2011-01-01
Background While mass media communications can be an important source of health information, there are substantial social disparities in health knowledge that may be related to media use. The purpose of this study is to investigate how the use of cancer-related health communications is patterned by race, ethnicity, language, and social class. Methodology/Principal Findings In a nationally-representative cross-sectional telephone survey, 5,187 U.S. adults provided information about demographic characteristics, cancer information seeking, and attention to and trust in health information from television, radio, newspaper, magazines, and the Internet. Cancer information seeking was lowest among Spanish-speaking Hispanics (odds ratio: 0.42; 95% confidence interval: 0.28–0.63) compared to non-Hispanic whites. Spanish-speaking Hispanics were more likely than non-Hispanic whites to pay attention to (odds ratio: 3.10; 95% confidence interval: 2.07–4.66) and trust (odds ratio: 2.61; 95% confidence interval: 1.53–4.47) health messages from the radio. Non-Hispanic blacks were more likely than non-Hispanic whites to pay attention to (odds ratio: 2.39; 95% confidence interval: 1.88–3.04) and trust (odds ratio: 2.16; 95% confidence interval: 1.61–2.90) health messages on television. Those who were college graduates tended to pay more attention to health information from newspapers (odds ratio: 1.98; 95% confidence interval: 1.42–2.75), magazines (odds ratio: 1.86; 95% confidence interval: 1.32–2.60), and the Internet (odds ratio: 4.74; 95% confidence interval: 2.70–8.31) and had less trust in cancer-related health information from television (odds ratio: 0.44; 95% confidence interval: 0.32–0.62) and radio (odds ratio: 0.54; 95% confidence interval: 0.34–0.86) compared to those who were not high school graduates. Conclusions/Significance Health media use is patterned by race, ethnicity, language and social class. Providing greater access to and enhancing the quality of health media by taking into account factors associated with social determinants may contribute to addressing social disparities in health. PMID:21267450
Applying Bootstrap Resampling to Compute Confidence Intervals for Various Statistics with R
ERIC Educational Resources Information Center
Dogan, C. Deha
2017-01-01
Background: Most of the studies in academic journals use p values to represent statistical significance. However, this is not a good indicator of practical significance. Although confidence intervals provide information about the precision of point estimation, they are, unfortunately, rarely used. The infrequent use of confidence intervals might…
ERIC Educational Resources Information Center
Zhang, Guangjian; Preacher, Kristopher J.; Luo, Shanhong
2010-01-01
This article is concerned with using the bootstrap to assign confidence intervals for rotated factor loadings and factor correlations in ordinary least squares exploratory factor analysis. Coverage performances of "SE"-based intervals, percentile intervals, bias-corrected percentile intervals, bias-corrected accelerated percentile…
Lai, Keke; Kelley, Ken
2011-06-01
In addition to evaluating a structural equation model (SEM) as a whole, often the model parameters are of interest and confidence intervals for those parameters are formed. Given a model with a good overall fit, it is entirely possible for the targeted effects of interest to have very wide confidence intervals, thus giving little information about the magnitude of the population targeted effects. With the goal of obtaining sufficiently narrow confidence intervals for the model parameters of interest, sample size planning methods for SEM are developed from the accuracy in parameter estimation approach. One method plans for the sample size so that the expected confidence interval width is sufficiently narrow. An extended procedure ensures that the obtained confidence interval will be no wider than desired, with some specified degree of assurance. A Monte Carlo simulation study was conducted that verified the effectiveness of the procedures in realistic situations. The methods developed have been implemented in the MBESS package in R so that they can be easily applied by researchers. © 2011 American Psychological Association
Commentary on Holmes et al. (2007): resolving the debate on when extinction risk is predictable.
Ellner, Stephen P; Holmes, Elizabeth E
2008-08-01
We reconcile the findings of Holmes et al. (Ecology Letters, 10, 2007, 1182) that 95% confidence intervals for quasi-extinction risk were narrow for many vertebrates of conservation concern, with previous theory predicting wide confidence intervals. We extend previous theory, concerning the precision of quasi-extinction estimates as a function of population dynamic parameters, prediction intervals and quasi-extinction thresholds, and provide an approximation that specifies the prediction interval and threshold combinations where quasi-extinction estimates are precise (vs. imprecise). This allows PVA practitioners to define the prediction interval and threshold regions of safety (low risk with high confidence), danger (high risk with high confidence), and uncertainty.
Uncertainty and inferred reserve estimates; the 1995 National Assessment
Attanasi, E.D.; Coburn, Timothy C.
2003-01-01
Inferred reserves are expected additions to proved reserves of oil and gas fields discovered as of a certain date. Inferred reserves accounted for 65 percent of the total oil and 34 percent of the total gas assessed in the U.S. Geological Survey's 1995 National Assessment of oil and gas in onshore and State offshore areas. The assessment predicted that over the 80-year period from 1992 through 2071, the sizes of pre-1992 discoveries in the lower 48 onshore and State offshore areas will increase by 48 billion barrels of oil (BBO) and 313 trillion cubic feet of wet gas (TCF). At that time, only point estimates were reported. This study presents a scheme to compute confidence intervals for these estimates. The recentered 90 percent confidence interval for the estimated inferred oil of 48 BBO is 25 BBO and 82 BBO. Similarly, the endpoints of the confidence interval about inferred reserve estimate of 313 TCF are 227 TCF and 439 TCF. The range of the estimates provides a basis for development of scenarios for projecting reserve additions and ultimately oil and gas production, information important to energy policy analysis.
Badenes-Ribera, Laura; Frias-Navarro, Dolores; Pascual-Soler, Marcos; Monterde-I-Bort, Héctor
2016-11-01
The statistical reform movement and the American Psychological Association (APA) defend the use of estimators of the effect size and its confidence intervals, as well as the interpretation of the clinical significance of the findings. A survey was conducted in which academic psychologists were asked about their behavior in designing and carrying out their studies. The sample was composed of 472 participants (45.8% men). The mean number of years as a university professor was 13.56 years (SD= 9.27). The use of effect-size estimators is becoming generalized, as well as the consideration of meta-analytic studies. However, several inadequate practices still persist. A traditional model of methodological behavior based on statistical significance tests is maintained, based on the predominance of Cohen’s d and the unadjusted R2/η2, which are not immune to outliers or departure from normality and the violations of statistical assumptions, and the under-reporting of confidence intervals of effect-size statistics. The paper concludes with recommendations for improving statistical practice.
Secretaries, depression and absenteeism.
Garrison, R; Eaton, W W
1992-01-01
This study examines the prevalence of Major Depressive Disorder; missed work; and mental health services use among secretaries and other women employed full-time. In a random sample of 3,484 women employed full-time, women employed as secretaries were significantly more likely to be depressed than other women even after controlling for socio-demographic characteristics (odds ratio = 1.69, 95% confidence interval = 1.05, 2.73). Secretaries were significantly more likely to report missing work in the last three months (odds ratio = 1.77, confidence interval = 1.01, 3.11); a finding not attributable to depression. Secretaries were also more likely to seek mental health services, but this finding was not significant (odds ratio = 1.78, confidence interval = 0.55, 5.78). It is possible that these findings are attributable to a selection effect whereby depressed women, and women who are likely to miss work, become secretaries. A second possibility is that women employed as secretaries have more "nonwork role stress" than other employed women. Alternatively, job conditions which result in dissatisfaction and stress may lead to depression and absenteeism. We believe our findings warrant further investigation into the work environment of secretaries.
Confidence interval or p-value?: part 4 of a series on evaluation of scientific publications.
du Prel, Jean-Baptist; Hommel, Gerhard; Röhrig, Bernd; Blettner, Maria
2009-05-01
An understanding of p-values and confidence intervals is necessary for the evaluation of scientific articles. This article will inform the reader of the meaning and interpretation of these two statistical concepts. The uses of these two statistical concepts and the differences between them are discussed on the basis of a selective literature search concerning the methods employed in scientific articles. P-values in scientific studies are used to determine whether a null hypothesis formulated before the performance of the study is to be accepted or rejected. In exploratory studies, p-values enable the recognition of any statistically noteworthy findings. Confidence intervals provide information about a range in which the true value lies with a certain degree of probability, as well as about the direction and strength of the demonstrated effect. This enables conclusions to be drawn about the statistical plausibility and clinical relevance of the study findings. It is often useful for both statistical measures to be reported in scientific articles, because they provide complementary types of information.
Microvascular anastomosis simulation using a chicken thigh model: Interval versus massed training.
Schoeff, Stephen; Hernandez, Brian; Robinson, Derek J; Jameson, Mark J; Shonka, David C
2017-11-01
To compare the effectiveness of massed versus interval training when teaching otolaryngology residents microvascular suturing on a validated microsurgical model. Otolaryngology residents were placed into interval (n = 7) or massed (n = 7) training groups. The interval group performed three separate 30-minute practice sessions separated by at least 1 week, and the massed group performed a single 90-minute practice session. Both groups viewed a video demonstration and recorded a pretest prior to the first training session. A post-test was administered following the last practice session. At an academic medical center, 14 otolaryngology residents were assigned using stratified randomization to interval or massed training. Blinded evaluators graded performance using a validated microvascular Objective Structured Assessment of Technical Skill tool. The tool is comprised of two major components: task-specific score (TSS) and global rating scale (GRS). Participants also received pre- and poststudy surveys to compare subjective confidence in multiple aspects of microvascular skill acquisition. Overall, all residents showed increased TSS and GRS on post- versus pretest. After completion of training, the interval group had a statistically significant increase in both TSS and GRS, whereas the massed group's increase was not significant. Residents in both groups reported significantly increased levels of confidence after completion of the study. Self-directed learning using a chicken thigh artery model may benefit microsurgical skills, competence, and confidence for resident surgeons. Interval training results in significant improvement in early development of microvascular anastomosis skills, whereas massed training does not. NA. Laryngoscope, 127:2490-2494, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.
Rukuni, Ruramayi; Bhattacharya, Sohinee; Murphy, Michael F; Roberts, David; Stanworth, Simon J; Knight, Marian
2016-05-01
Antenatal anemia is a major public health problem in the UK, yet there is limited high quality evidence for associated poor clinical outcomes. The objectives of this study were to estimate the incidence and clinical outcomes of antenatal anemia in a Scottish population. A retrospective cohort study of 80 422 singleton pregnancies was conducted using data from the Aberdeen Maternal and Neonatal Databank between 1995 and 2012. Antenatal anemia was defined as haemoglobin ≤ 10 g/dl during pregnancy. Incidence was calculated with 95% confidence intervals and compared over time using a chi-squared test for trend. Multivariable logistic regression was used to adjust for confounding variables. Results are presented as adjusted odds ratios with 95% confidence interval. The overall incidence of antenatal anemia was 9.3 cases/100 singleton pregnancies (95% confidence interval 9.1-9.5), decreasing from 16.9/100 to 4.1/100 singleton pregnancies between 1995 and 2012 (p < 0.001). Maternal anemia was associated with antepartum hemorrhage (adjusted odds ratio 1.26, 95% confidence interval 1.17-1.36), postpartum infection (adjusted odds ratio 1.89, 95% confidence interval 1.39-2.57), transfusion (adjusted odds ratio 1.87, 95% confidence interval 1.65-2.13) and stillbirth (adjusted odds ratio 1.42, 95% confidence interval 1.04-1.94), reduced odds of postpartum hemorrhage (adjusted odds ratio 0.92, 95% confidence interval 0.86-0.98) and low birthweight (adjusted odds ratio 0.77, 95% confidence interval 0.69-0.86). No other outcomes were statistically significant. This study shows the incidence of antenatal anemia is decreasing steadily within this Scottish population. However, given that anemia is a readily correctable risk factor for major causes of morbidity and mortality in the UK, further work is required to investigate appropriate preventive measures. © 2016 Nordic Federation of Societies of Obstetrics and Gynecology.
Anand, Kanwaljeet J S; Clark, Amy E; Willson, Douglas F; Berger, John; Meert, Kathleen L; Zimmerman, Jerry J; Harrison, Rick; Carcillo, Joseph A; Newth, Christopher J L; Bisping, Stephanie; Holubkov, Richard; Dean, J Michael; Nicholson, Carol E
2013-01-01
To examine the clinical factors associated with increased opioid dose among mechanically ventilated children in the pediatric intensive care unit. Prospective, observational study with 100% accrual of eligible patients. Seven pediatric intensive care units from tertiary-care children's hospitals in the Collaborative Pediatric Critical Care Research Network. Four hundred nineteen children treated with morphine or fentanyl infusions. None. Data on opioid use, concomitant therapy, demographic and explanatory variables were collected. Significant variability occurred in clinical practices, with up to 100-fold differences in baseline opioid doses, average daily or total doses, or peak infusion rates. Opioid exposure for 7 or 14 days required doubling of the daily opioid dose in 16% patients (95% confidence interval 12%-19%) and 20% patients (95% confidence interval 16%-24%), respectively. Among patients receiving opioids for longer than 3 days (n = 225), this occurred in 28% (95% confidence interval 22%-33%) and 35% (95% confidence interval 29%-41%) by 7 or 14 days, respectively. Doubling of the opioid dose was more likely to occur following opioid infusions for 7 days or longer (odds ratio 7.9, 95% confidence interval 4.3-14.3; p < 0.001) or co-therapy with midazolam (odds ratio 5.6, 95% confidence interval 2.4-12.9; p < 0.001), and it was less likely to occur if morphine was used as the primary opioid (vs. fentanyl) (odds ratio 0.48, 95% confidence interval 0.25-0.92; p = 0.03), for patients receiving higher initial doses (odds ratio 0.96, 95% confidence interval 0.95-0.98; p < 0.001), or if patients had prior pediatric intensive care unit admissions (odds ratio 0.37, 95% confidence interval 0.15-0.89; p = 0.03). Mechanically ventilated children require increasing opioid doses, often associated with prolonged opioid exposure or the need for additional sedation. Efforts to reduce prolonged opioid exposure and clinical practice variation may prevent the complications of opioid therapy.
Temporal Variability in the Deglutition Literature
Molfenter, Sonja M.; Steele, Catriona M.
2013-01-01
A literature review was conducted on temporal measures of swallowing in healthy individuals with the purpose of determining the degree of variability present in such measures within the literature. A total of 46 studies that met inclusion criteria were reviewed. The definitions and descriptive statistics for all reported temporal parameters were compiled for meta-analysis. In total, 119 different temporal parameters were found in the literature. The three most-frequently occurring durational measures were: UES opening, laryngeal closure and hyoid movement. The three most-frequently occurring interval measures were: stage transition duration, pharyngeal transit time and duration from laryngeal closure to UES opening. Subtle variations in operational definitions across studies were noted, making the comparison of data challenging. Analysis of forest plots compiling descriptive statistical data (means and 95% confidence intervals) across studies revealed differing degrees of variability across durations and intervals. Two parameters (UES opening duration and the laryngeal-closure-to-UES-opening interval) demonstrated the least variability, reflected by small ranges for mean values and tight confidence intervals. Trends emerged for factors of bolus size and participant age for some variables. Other potential sources of variability are discussed. PMID:22366761
ERIC Educational Resources Information Center
Larson-Hall, Jenifer; Plonsky, Luke
2015-01-01
This paper presents a set of guidelines for reporting on five types of quantitative data issues: (1) Descriptive statistics, (2) Effect sizes and confidence intervals, (3) Instrument reliability, (4) Visual displays of data, and (5) Raw data. Our recommendations are derived mainly from various professional sources related to L2 research but…
Are Household Firearms Stored Less Safely in Homes With Adolescents?
Johnson, Renee M.; Miller, Matthew; Vriniotis, Mary; Azrael, Deborah; Hemenway, David
2011-01-01
Objective To examine whether firearms are more frequently stored loaded, unlocked, or both in households with adolescents only (aged 13-17 years) compared with households with younger children only (aged 0-12 years). Design Random-digit-dial survey on firearms (n=2770). We computed bivariate associations between the presence of adolescents and firearm storage practices. Statistical significance was assessed using prevalence ratios with 95% confidence intervals. Setting United States. Participants Survey respondents with children (aged <18 years) who reported the presence of a household firearm. Main Outcome Measures Prevalence of firearms in the home stored loaded and/or unlocked. Results Of the 392 respondents, 22% had a loaded firearm, 32% had an unlocked firearm, and 8% had a firearm stored loaded and unlocked. Compared with households with younger children, households with adolescents only were somewhat more likely to store a firearm unlocked (42% vs 29%; prevalence ratio, 1.48; 95% confidence interval, 1.04-2.02), loaded (26% vs 20%; prevalence ratio, 1.25; 95% confidence interval, 0.82-1.91), or both (10% vs 8%; prevalence ratio, 1.43; 95% confidence interval, 0.64-3.19). Conclusions Parents of adolescents appear to be more likely to keep household firearms stored unsafely, especially with regard to keeping firearms unlocked. This is of concern because most youth firearm injuries happen to adolescents. Firearm injury prevention programs should directly target parents of adolescents to promote safe firearm storage. PMID:16894076
Honardar, Marzieh R; Posner, Karen L; Domino, Karen B
2017-12-01
This retrospective case series analyzed 45 malpractice claims for delayed detection of esophageal intubation from the Anesthesia Closed Claims Project. Inclusion criteria were cases from 1995 to 2013, after adoption of identification of CO2 in expired gas to verify correct endotracheal tube position as a monitoring standard by the American Society of Anesthesiologists. Forty-nine percent (95% confidence interval 34%-64%) occurred in the operating room or other anesthesia location where CO2 detection equipment should have been available. The most common factors contributing to delayed detection were not using, ignoring, or misinterpreting CO2 readings. Misdiagnosis, as with bronchospasm, occurred in 33% (95% confidence interval 20%).
Confidence Intervals for the Mean: To Bootstrap or Not to Bootstrap
ERIC Educational Resources Information Center
Calzada, Maria E.; Gardner, Holly
2011-01-01
The results of a simulation conducted by a research team involving undergraduate and high school students indicate that when data is symmetric the student's "t" confidence interval for a mean is superior to the studied non-parametric bootstrap confidence intervals. When data is skewed and for sample sizes n greater than or equal to 10,…
ERIC Educational Resources Information Center
Hoekstra, Rink; Johnson, Addie; Kiers, Henk A. L.
2012-01-01
The use of confidence intervals (CIs) as an addition or as an alternative to null hypothesis significance testing (NHST) has been promoted as a means to make researchers more aware of the uncertainty that is inherent in statistical inference. Little is known, however, about whether presenting results via CIs affects how readers judge the…
Using Asymptotic Results to Obtain a Confidence Interval for the Population Median
ERIC Educational Resources Information Center
Jamshidian, M.; Khatoonabadi, M.
2007-01-01
Almost all introductory and intermediate level statistics textbooks include the topic of confidence interval for the population mean. Almost all these texts introduce the median as a robust measure of central tendency. Only a few of these books, however, cover inference on the population median and in particular confidence interval for the median.…
ERIC Educational Resources Information Center
Barnette, J. Jackson
2005-01-01
An Excel program developed to assist researchers in the determination and presentation of confidence intervals around commonly used score reliability coefficients is described. The software includes programs to determine confidence intervals for Cronbachs alpha, Pearson r-based coefficients such as those used in test-retest and alternate forms…
Confidence intervals from single observations in forest research
Harry T. Valentine; George M. Furnival; Timothy G. Gregoire
1991-01-01
A procedure for constructing confidence intervals and testing hypothese from a single trial or observation is reviewed. The procedure requires a prior, fixed estimate or guess of the outcome of an experiment or sampling. Two examples of applications are described: a confidence interval is constructed for the expected outcome of a systematic sampling of a forested tract...
Male partner reproductive coercion among women veterans.
Rosenfeld, Elian A; Miller, Elizabeth; Zhao, Xinhua; Sileanu, Florentina E; Mor, Maria K; Borrero, Sonya
2018-02-01
Male partner reproductive coercion is defined as male partners' attempts to promote pregnancy through interference with women's contraceptive behaviors and reproductive decision-making. Male partners may try to promote pregnancy through birth control sabotage such as taking away or destroying their partners' contraceptives, refusing to wear condoms, and/or verbally pressuring their partners to abstain from contraceptive use. Reproductive coercion is associated with an elevated risk for unintended pregnancy. Women who experience intimate partner violence, who are in racial/ethnic minorities, and who are of lower socioeconomic status are more likely to experience reproductive coercion. Women veterans who use Veterans Affairs for health care may be particularly vulnerable to reproductive coercion because they are disproportionally from racial/ethnic minority groups and experience high rates of intimate partner violence. We sought to examine the prevalence, correlates, and impact of reproductive coercion among women veterans who are served by the Veterans Affairs healthcare system. We analyzed data from a national telephone survey of women veterans aged 18-44 years, with no history of sterilization or hysterectomy, who had received care within the Veterans Affairs system in the previous 12 months. Participants who had sex with men in the last year were asked if they experienced male partner reproductive coercion. Adjusted logistic regression was used to examine the relationship between participant characteristics and male partner reproductive coercion and the relationship between reproductive coercion and the outcomes of contraceptive method used at last sex and pregnancy and unintended pregnancy in the last year. Among the 1241 women veterans in our study cohort, 11% reported experiencing male partner reproductive coercion in the past year. Black women, younger women, and single women were more likely to report reproductive coercion than their white, older, and married counterparts. Women who experienced military sexual trauma were also more likely to report reproductive coercion compared with women who did not report military sexual trauma. In adjusted analyses, compared with women who did not experience reproductive coercion, those who did were less likely at last sex to have used any method of contraception (76% vs 80%; adjusted odds ratio, 0.61; 95% confidence interval, 0.38-0.96), prescription contraception (43% vs 55%; adjusted odds ratio, 0.62; 95% confidence interval, 0.43-0.91), and their ideal method of contraception (35% vs 45%; adjusted odds ratio, 0.63; 95% confidence interval, 0.43-0.93). Those who reported coercion were more likely to have had a pregnancy in the last year (14% vs 10%; adjusted odds ratio, 2.07; 95% confidence interval, 1.17-3.64); there were no significant differences in unintended pregnancy by coercion status (6% vs 4%; adjusted odds ratio, 1.63; 95% confidence interval, 0.71-3.76). Eleven percent of women veterans in our sample experienced male partner reproductive coercion, which may impact their use of contraception and ability to prevent pregnancy. Published by Elsevier Inc.
Night-shift work and breast cancer risk in a cohort of Chinese women.
Pronk, Anjoeka; Ji, Bu-Tian; Shu, Xiao-Ou; Xue, Shouzheng; Yang, Gong; Li, Hong-Lan; Rothman, Nathaniel; Gao, Yu-Tang; Zheng, Wei; Chow, Wong-Ho
2010-05-01
Shift work involving disruption of circadian rhythms has been classified as a probable cause of human cancer by the International Agency for Research on Cancer, based on limited epidemiologic evidence and abundant experimental evidence. The authors investigated this association in a population-based prospective cohort study of Chinese women. At baseline (1996-2000), information on lifetime occupational history was obtained from 73,049 women. Lifetime night-shift exposure indices were created using a job exposure matrix. During 2002-2004, self-reported data on frequency and duration of night-shift work were collected. Hazard ratios and 95% confidence intervals, adjusted for major breast cancer risk factors, were calculated. During follow-up through 2007, 717 incident cases of breast cancer were diagnosed. Breast cancer risk was not associated with ever working the night shift on the basis of the job exposure matrix (adjusted hazard ratio = 1.0, 95% confidence interval: 0.9, 1.2) or self-reported history of night-shift work (adjusted hazard ratio = 0.9, 95% confidence interval: 0.7, 1.1). Risk was also not associated with frequency, duration, or cumulative amount of night-shift work. There were no indications of effect modification. The lack of an association between night-shift work and breast cancer adds to the inconsistent epidemiologic evidence. It may be premature to consider shift work a cause of cancer.
Parks, Christine G; Sandler, Dale P
2018-01-01
Abstract Farming and pesticide exposure may influence risk of rheumatoid arthritis (RA); the role of early-life pesticide exposure is unknown. The Sister Study includes a US national cohort of women aged 35–74 years (enrolled 2004–2009); we examined childhood pesticide exposure in women in this cohort with adult-onset RA. Cases (n = 424) were compared with 48,919 noncases. Data included pesticide use at the longest childhood residence through age 14 years, farm residence of at least 12 months with agricultural pesticide exposure through age 18 years, and maternal farm experience. Odds ratios and 95% confidence intervals were adjusted for age, race or ethnicity, education, smoking, and childhood socioeconomic factors. Cases with RA reported more frequent and direct (personal) residential pesticide use in childhood (for infrequent/indirect pesticide use, odds ratio (OR) = 1.1; for frequent/direct use, OR = 1.8; P for trend = 0.013). Compared with women without residential farm history, odds of having RA increased for those reporting a childhood-only farm residence with personal exposure to pesticides used on crops (OR = 1.8, 95% confidence interval: 1.1, 2.9) or livestock (OR = 2.0, 95% confidence interval: 1.2, 3.3). Our findings suggest adult-onset RA may be related to childhood exposure to residential and agricultural pesticides, and support further investigations of lifetime pesticide use in RA. PMID:29020148
Letenneur, L; Launer, L J; Andersen, K; Dewey, M E; Ott, A; Copeland, J R; Dartigues, J F; Kragh-Sorensen, P; Baldereschi, M; Brayne, C; Lobo, A; Martinez-Lage, J M; Stijnen, T; Hofman, A
2000-06-01
The hypothesis that a low educational level increases the risk for Alzheimer's disease remains controversial. The authors studied the association of years of schooling with the risk for incident dementia and Alzheimer's disease by using pooled data from four European population-based follow-up studies. Dementia cases were identified in a two-stage procedure that included a detailed diagnostic assessment of screen-positive subjects. Dementia and Alzheimer's disease were diagnosed by using international research criteria. Educational level was categorized by years of schooling as low (< or =7), middle (8-11), or high (> or =12). Relative risks (95% confidence intervals) were estimated by using Poisson regression, adjusting for age, sex, study center, smoking status, and self-reported myocardial infarction and stroke. There were 493 (328) incident cases of dementia (Alzheimer's disease) and 28,061 (27,839) person-years of follow-up. Compared with women with a high level of education, those with low and middle levels of education had 4.3 (95% confidence interval: 1.5, 11.9) and 2.6 (95% confidence interval: 1.0, 7.1) times increased risks, respectively, for Alzheimer's disease. The risk estimates for men were close to 1.0. Finding an association of education with Alzheimer's disease for women only raises the possibility that unmeasured confounding explains the previously reported increased risk for Alzheimer's disease for persons with low levels of education.
Roberge, Stéphanie; Nicolaides, Kypros; Demers, Suzanne; Hyett, Jon; Chaillet, Nils; Bujold, Emmanuel
2017-02-01
Preeclampsia and fetal growth restriction are major causes of perinatal death and handicap in survivors. Randomized clinical trials have reported that the risk of preeclampsia, severe preeclampsia, and fetal growth restriction can be reduced by the prophylactic use of aspirin in high-risk women, but the appropriate dose of the drug to achieve this objective is not certain. We sought to estimate the impact of aspirin dosage on the prevention of preeclampsia, severe preeclampsia, and fetal growth restriction. We performed a systematic review and meta-analysis of randomized controlled trials comparing the effect of daily aspirin or placebo (or no treatment) during pregnancy. We searched MEDLINE, Embase, Web of Science, and Cochrane Central Register of Controlled Trials up to December 2015, and study bibliographies were reviewed. Authors were contacted to obtain additional data when needed. Relative risks for preeclampsia, severe preeclampsia, and fetal growth restriction were calculated with 95% confidence intervals using random-effect models. Dose-response effect was evaluated using meta-regression and reported as adjusted R 2 . Analyses were stratified according to gestational age at initiation of aspirin (≤16 and >16 weeks) and repeated after exclusion of studies at high risk of biases. In all, 45 randomized controlled trials included a total of 20,909 pregnant women randomized to between 50-150 mg of aspirin daily. When aspirin was initiated at ≤16 weeks, there was a significant reduction and a dose-response effect for the prevention of preeclampsia (relative risk, 0.57; 95% confidence interval, 0.43-0.75; P < .001; R 2 , 44%; P = .036), severe preeclampsia (relative risk, 0.47; 95% confidence interval, 0.26-0.83; P = .009; R 2 , 100%; P = .008), and fetal growth restriction (relative risk, 0.56; 95% confidence interval, 0.44-0.70; P < .001; R 2 , 100%; P = .044) with higher dosages of aspirin being associated with greater reduction of the 3 outcomes. Similar results were observed after the exclusion of studies at high risk of biases. When aspirin was initiated at >16 weeks, there was a smaller reduction of preeclampsia (relative risk, 0.81; 95% confidence interval, 0.66-0.99; P = .04) without relationship with aspirin dosage (R 2 , 0%; P = .941). Aspirin initiated at >16 weeks was not associated with a risk reduction or a dose-response effect for severe preeclampsia (relative risk, 0.85; 95% confidence interval, 0.64-1.14; P = .28; R 2 , 0%; P = .838) and fetal growth restriction (relative risk, 0.95; 95% confidence interval, 0.86-1.05; P = .34; R 2 , not available; P = .563). Prevention of preeclampsia and fetal growth restriction using aspirin in early pregnancy is associated with a dose-response effect. Low-dose aspirin initiated at >16 weeks' gestation has a modest or no impact on the risk of preeclampsia, severe preeclampsia, and fetal growth restriction. Women at high risk for those outcomes should be identified in early pregnancy. Copyright © 2016 Elsevier Inc. All rights reserved.
Simpson, Colin R; Steiner, Markus Fc; Cezard, Genevieve; Bansal, Narinder; Fischbacher, Colin; Douglas, Anne; Bhopal, Raj; Sheikh, Aziz
2015-10-01
There is evidence of substantial ethnic variations in asthma morbidity and the risk of hospitalisation, but the picture in relation to lower respiratory tract infections is unclear. We carried out an observational study to identify ethnic group differences for lower respiratory tract infections. A retrospective, cohort study. Scotland. 4.65 million people on whom information was available from the 2001 census, followed from May 2001 to April 2010. Hospitalisations and deaths (any time following first hospitalisation) from lower respiratory tract infections, adjusted risk ratios and hazard ratios by ethnicity and sex were calculated. We multiplied ratios and confidence intervals by 100, so the reference Scottish White population's risk ratio and hazard ratio was 100. Among men, adjusted risk ratios for lower respiratory tract infection hospitalisation were lower in Other White British (80, 95% confidence interval 73-86) and Chinese (69, 95% confidence interval 56-84) populations and higher in Pakistani groups (152, 95% confidence interval 136-169). In women, results were mostly similar to those in men (e.g. Chinese 68, 95% confidence interval 56-82), although higher adjusted risk ratios were found among women of the Other South Asians group (145, 95% confidence interval 120-175). Survival (adjusted hazard ratio) following lower respiratory tract infection for Pakistani men (54, 95% confidence interval 39-74) and women (31, 95% confidence interval 18-53) was better than the reference population. Substantial differences in the rates of lower respiratory tract infections amongst different ethnic groups in Scotland were found. Pakistani men and women had particularly high rates of lower respiratory tract infection hospitalisation. The reasons behind the high rates of lower respiratory tract infection in the Pakistani community are now required. © The Royal Society of Medicine.
Risk factors of childhood asthma in children attending Lyari General Hospital.
Kamran, Amber; Hanif, Shahina; Murtaza, Ghulam
2015-06-01
To determine the factors associated with asthma in children. The case-control study was conducted in the paediatrics clinic of Lyari General Hospital, Karachi, from May to October 2010. Children 1-15 years of age attending the clinic represented the cases, while the control group had children who were closely related (sibling or cousin) to the cases but did not have the symptoms of disease at the time. Data was collected through a proforma and analysed using SPSS 10. Of the total 346 subjects, 173(50%) each comprised the two groups. According to univariable analysis the risk factors were presence of at least one smoker (odds ratio: 3.6; 95% confidence interval: 2.3-5.8), resident of kacha house (odds ratio: 16.2; 95% confidence interval: 3.8-69.5),living in room without windows (odds ratio: 9.3; 95% confidence interval: 2.1-40.9) and living in houses without adequate sunlight (odds ratio: 1.6; 95% confidence interval: 1.2-2.4).Using multivariable modelling, family history of asthma (odds ratio: 5.9; 95% confidence interval: 3.1-11.6), presence of at least one smoker at home (odds ratio: 4.1; 95% confidence interval: 2.3-7.2), people living in a room without a window (odds ratio: 5.5; 95% confidence interval: 1.15-26.3) and people living in an area without adequate sunlight (odds ratio: 2.2; 95% confidence interval: 1.13-4.31) were found to be independent risk factors of asthma in children adjusting for age, gender and history of weaning. Family history of asthma, children living with at least one smoker at home, room without windows and people living in an area without sunlight were major risk factors of childhood asthma.
Self-reported bruxism mirrors anxiety and stress in adults
Lobbezoo, Frank; Ahlberg, Kristiina; Manfredini, Daniele; Hublin, Christer; Sinisalo, Juha; Könönen, Mauno; Savolainen, Aslak
2013-01-01
Objectives: The aims were to analyze whether the levels of self-reported bruxism and anxiety associate among otherwise healthy subjects, and to investigate the independent effects of anxiety and stress experience on the probability of self-reported bruxism. Study Design: As part of a study on irregular shift work, a questionnaire was mailed to all employees of the Finnish Broadcasting Company with irregular shift work (number of subjects: n=750) and to an equal number of randomly selected employees in the same company with regular eight-hour daytime work. Results: The response rates were 82.3% (56.6 % men) and 34.3 % (46.7 % men), respectively. Among the 874 respondents, those aware of more frequent bruxism reported significantly more severe anxiety (p<0.001). Adjusted by age and gender, frequent bruxers were more than two times more likely to report severe stress (odds ratio 2.5; 95% confidence interval 1.5-4.2) and anxiety (odds ratio 2.2; 95% confidence interval 1.3-3.6) than non-or-mild bruxers. Conclusions: Present findings suggest that self-reported bruxism and psychological states such as anxiety or stress may be related in working age subjects. Key words:Bruxism, self-report, anxiety, stress, adult. PMID:22926484
Krishnamoorthy, K; Oral, Evrim
2017-12-01
Standardized likelihood ratio test (SLRT) for testing the equality of means of several log-normal distributions is proposed. The properties of the SLRT and an available modified likelihood ratio test (MLRT) and a generalized variable (GV) test are evaluated by Monte Carlo simulation and compared. Evaluation studies indicate that the SLRT is accurate even for small samples, whereas the MLRT could be quite liberal for some parameter values, and the GV test is in general conservative and less powerful than the SLRT. Furthermore, a closed-form approximate confidence interval for the common mean of several log-normal distributions is developed using the method of variance estimate recovery, and compared with the generalized confidence interval with respect to coverage probabilities and precision. Simulation studies indicate that the proposed confidence interval is accurate and better than the generalized confidence interval in terms of coverage probabilities. The methods are illustrated using two examples.
NASA Astrophysics Data System (ADS)
Salamat, Mona; Zare, Mehdi; Holschneider, Matthias; Zöller, Gert
2017-03-01
The problem of estimating the maximum possible earthquake magnitude m_max has attracted growing attention in recent years. Due to sparse data, the role of uncertainties becomes crucial. In this work, we determine the uncertainties related to the maximum magnitude in terms of confidence intervals. Using an earthquake catalog of Iran, m_max is estimated for different predefined levels of confidence in six seismotectonic zones. Assuming the doubly truncated Gutenberg-Richter distribution as a statistical model for earthquake magnitudes, confidence intervals for the maximum possible magnitude of earthquakes are calculated in each zone. While the lower limit of the confidence interval is the magnitude of the maximum observed event,the upper limit is calculated from the catalog and the statistical model. For this aim, we use the original catalog which no declustering methods applied on as well as a declustered version of the catalog. Based on the study by Holschneider et al. (Bull Seismol Soc Am 101(4):1649-1659, 2011), the confidence interval for m_max is frequently unbounded, especially if high levels of confidence are required. In this case, no information is gained from the data. Therefore, we elaborate for which settings finite confidence levels are obtained. In this work, Iran is divided into six seismotectonic zones, namely Alborz, Azerbaijan, Zagros, Makran, Kopet Dagh, Central Iran. Although calculations of the confidence interval in Central Iran and Zagros seismotectonic zones are relatively acceptable for meaningful levels of confidence, results in Kopet Dagh, Alborz, Azerbaijan and Makran are not that much promising. The results indicate that estimating m_max from an earthquake catalog for reasonable levels of confidence alone is almost impossible.
Grzywacz, Joseph G; Alterman, Toni; Gabbard, Susan; Shen, Rui; Nakamoto, Jorge; Carroll, Daniel J; Muntaner, Carles
2014-01-01
Improve understanding of the potential occupational health impact of how agricultural jobs are organized. Exposure to low job control, high psychological demands, and high job strain were hypothesized to have greater risk for poor self-rated physical health and elevated depressive symptoms. Cross-sectional data (N = 3691) obtained using the Work Organization and Psychosocial Factors module of the US National Agricultural Workers Survey fielded in 2009-2010. More than one fifth (22.4%) of farmworkers reported fair/poor health, and 8.7% reported elevated depressive symptoms. High psychological demand was associated with increased risk of fair/poor health (odds ratio, 1.73; 95% confidence interval, 1.4 to 2.2) and elevated depressive symptoms (odds ratio, 2.6; 95% confidence interval, 1.9 to 3.8). The organization of work in field agriculture may pose risks for poor occupational health outcomes among a vulnerable worker population.
Mirabelli, Maria C; London, Stephanie J; Charles, Luenda E; Pompeii, Lisa A; Wagenknecht, Lynne E
2012-02-01
To examine associations between occupation and respiratory health in a large, population-based cohort of adults in the United States. Data from 15,273 participants, aged 45 to 64 years, in the Atherosclerosis Risk in Communities study were used to examine associations of current or most recent job held with the prevalence of self-reported chronic cough, chronic bronchitis, wheezing, asthma, and measures of lung function collected by spirometry. Eleven percent of participants reported wheezing and 9% were classified as having airway obstruction. Compared with individuals in managerial and administrative jobs, increased prevalences of respiratory outcomes were observed among participants in selected occupations, including construction and extractive trades (wheezing, prevalence ratio = 1.92, 95% confidence interval = 1.35, 2.73; airway obstruction, prevalence ratio = 1.31, 95% confidence interval = 1.05, 1.65). Specific occupations are associated with adverse respiratory health.
Armellino, Donna; Cifu, Kelly; Wallace, Maureen; Johnson, Sherly; DiCapua, John; Dowling, Oonagh; Jacobs, Mitchel; Browning, Susan
2018-05-01
A pilot initiative to assess the use of remote video auditing in monitoring compliance with manual-cleaning protocols for endoscopic retrograde cholangiopancreatography (ERCP) endoscopes was performed. Compliance with manual-cleaning steps following the initiation of feedback was measured. A video feed of the ERCP reprocessing room was provided to remote auditors who scored items of an ERCP endoscope manual-cleaning checklist. Compliance feedback was provided in the form of reports and reeducation. Outcomes were reported as checklist compliance. The use of remote video auditing to document manual processing is a feasible approach and feedback and reeducation increased manual-cleaning compliance from 53.1% (95% confidence interval, 34.7-71.6) to 98.9% (95.0% confidence interval, 98.1-99.6). Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Brownstein, Daniel J; Salagre, Estela; Köhler, Cristiano; Stubbs, Brendon; Vian, João; Pereira, Ciria; Chavarria, Victor; Karmakar, Chandan; Turner, Alyna; Quevedo, João; Carvalho, André F; Berk, Michael; Fernandes, Brisa S
2018-01-01
It is unclear whether blockade of the angiotensin system has effects on mental health. Our objective was to determine the impact of angiotensin converting enzyme inhibitors and angiotensin II type 1 receptor (AT1R) blockers on mental health domain of quality of life. Meta-analysis of published literature. PubMed and clinicaltrials.gov databases. The last search was conducted in January 2017. Randomized controlled trials comparing any angiotensin converting enzyme inhibitor or AT1R blocker versus placebo or non-angiotensin converting enzyme inhibitor or non-AT1R blocker were selected. Study participants were adults without any major physical symptoms. We adhered to meta-analysis reporting methods as per PRISMA and the Cochrane Collaboration. Eleven studies were included in the analysis. When compared with placebo or other antihypertensive medications, AT1R blockers and angiotensin converting enzyme inhibitors were associated with improved overall quality of life (standard mean difference = 0.11, 95% confidence interval = [0.08, 0.14], p < 0.0001), positive wellbeing (standard mean difference = 0.11, 95% confidence interval = [0.05, 0.17], p < 0.0001), mental (standard mean difference = 0.15, 95% confidence interval = [0.06, 0.25], p < 0.0001), and anxiety (standard mean difference = 0.08, 95% confidence interval = [0.01, 0.16], p < 0.0001) domains of QoL. No significant difference was found for the depression domain (standard mean difference = 0.05, 95% confidence interval = [0.02, 0.12], p = 0.15). Use of angiotensin blockers and inhibitors for the treatment of hypertension in otherwise healthy adults is associated with improved mental health domains of quality of life. Mental health quality of life was a secondary outcome in the included studies. Research specifically designed to analyse the usefulness of drugs that block the angiotensin system is necessary to properly evaluate this novel psychiatric target.
Involving American Indians and medically underserved rural populations in cancer clinical trials.
Guadagnolo, B Ashleigh; Petereit, Daniel G; Helbig, Petra; Koop, David; Kussman, Patricia; Fox Dunn, Emily; Patnaik, Asha
2009-12-01
To assess cancer clinical trial recruitment and reasons for nonaccrual among a rural, medically underserved population served by a community-based cancer care center. We prospectively tracked clinical trial enrollment incidence among all new patients presenting at the Rapid City Regional Cancer Care Institute. Evaluating physicians completed questionnaires for each patient regarding clinical trial enrollment status and primary reasons for nonenrollment. Patients who identified as American Indian were referred to a program where patients were assisted in navigating the medical system by trained, culturally competent staff. Between September 2006 and January 2008, 891 new cancer patients were evaluated. Seventy-eight patients (9%; 95% confidence intervals, 7-11%) were enrolled on a clinical treatment trial. For 73% (95% confidence intervals, 69-75%) of patients (646 of 891) lack of relevant protocol availability or protocol inclusion criteria restrictiveness was the reason for nonenrollment. Only 45 (5%; 95% confidence intervals, 4-7%) patients refused enrollment on a trial. Of the 78 enrolled on a trial, 6 (8%; 95% confidence intervals, 3-16%) were American Indian. Three additional American Indian patients were enrolled under a nontreatment cancer control trial, bringing the total percentage enrolled of the 94 American Indians who presented to the clinic to 10% (95% confidence intervals, 5-17%). Eligibility rates were unable to be calculated and cross validation of the number in the cohort via registries or ICD-9 codes was not performed. Clinical trial participation in this medically underserved population was low overall, but approximately 3-fold higher than reported national accrual rates. Lack of availability of protocols for common cancer sites as well as stringent protocol inclusion criteria were the primary obstacles to clinical trial enrollment. Targeted interventions using a Patient Navigation program were used to engage AI patients and may have resulted in higher clinical trial enrollment among this racial/ethnic group.
Involving American Indians and medically underserved rural populations in cancer clinical trials
Guadagnolo, B Ashleigh; Petereit, Daniel G; Helbig, Petra; Koop, David; Kussman, Patricia; Dunn, Emily Fox; Patnaik, Asha
2010-01-01
Purpose To assess cancer clinical trial recruitment and reasons for nonaccrual among a rural, medically underserved population served by a community-based cancer care center. Methods We prospectively tracked clinical trial enrollment incidence among all new patients presenting at the Rapid City Regional Cancer Care Institute. Evaluating physicians completed questionnaires for each patient regarding clinical trial enrollment status and primary reasons for nonenrollment. Patients who identified as American Indian were referred to a program where patients were assisted in navigating the medical system by trained, culturally competent staff. Results Between September 2006 and January 2008, 891 new cancer patients were evaluated. Seventy-eight patients (9%; 95% confidence intervals, 7–11%) were enrolled on a clinical treatment trial. For 73% (95% confidence intervals, 69–75%) of patients (646 of 891) lack of relevant protocol availability or protocol inclusion criteria restrictiveness was the reason for nonenrollment. Only 45 (5%; 95% confidence intervals, 4–7%) patients refused enrollment on a trial. Of the 78 enrolled on a trial, 6 (8%; 95% confidence intervals, 3–16%) were American Indian. Three additional American Indian patients were enrolled under a nontreatment cancer control trial, bringing the total percentage enrolled of the 94 American Indians who presented to the clinic to 10% (95% confidence intervals, 5–17%). Limitations Eligibility rates were unable to be calculated and cross validation of the number in the cohort via registries or ICD-9 codes was not performed. Conclusion Clinical trial participation in this medically underserved population was low overall, but approximately 3-fold higher than reported national accrual rates. Lack of availability of protocols for common cancer sites as well as stringent protocol inclusion criteria were the primary obstacles to clinical trial enrollment. Targeted interventions using a Patient Navigation program were used to engage AI patients and may have resulted in higher clinical trial enrollment among this racial/ethnic group. PMID:19933720
Pivodic, Lara; Harding, Richard; Calanzani, Natalia; McCrone, Paul; Hall, Sue; Deliens, Luc; Higginson, Irene J; Gomes, Barbara
2016-01-01
Background: Stronger generalist end-of-life care at home for people with cancer is called for but the quality of end-of-life care delivered by general practitioners has been questioned. Aim: To determine the degree of and factors associated with bereaved relatives’ satisfaction with home end-of-life care delivered by general practitioners to cancer patients. Design: Population-based mortality followback survey. Setting/participants: Bereaved relatives of people who died of cancer in London, United Kingdom (identified from death registrations in 2009–2010), were invited to complete a postal questionnaire surveying the deceased’s final 3 months of life. Results: Questionnaires were completed for 596 decedents of whom 548 spent at least 1 day at home in the last 3 months of life. Of the respondents, 55% (95% confidence interval: 51%–59%) reported excellent/very good home care by general practitioners, compared with 78% (95% confidence interval: 74%–82%) for specialist palliative care providers and 68% (95% confidence interval: 64%–73%) for district/community/private nurses. The odds of high satisfaction (excellent/very good) with end-of-life care by general practitioners doubled if general practitioners made three or more compared with one or no home visits in the patient’s last 3 months of life (adjusted odds ratio: 2.54 (95% confidence interval: 1.52–4.24)) and halved if the patient died at hospital rather than at home (adjusted odds ratio: 0.55 (95% confidence interval: 0.31–0.998)). Conclusion: There is considerable room for improvement in the satisfaction with home care provided by general practitioners to terminally ill cancer patients. Ensuring an adequate offer of home visits by general practitioners may help to achieve this goal. PMID:26036688
Yang, Bo Ram; Kim, Ye-Jee; Kim, Mi-Sook; Jung, Sun-Young; Choi, Nam-Kyong; Hwang, Byungkwan; Park, Byung-Joo; Lee, Joongyub
2018-05-23
Zolpidem is one of the most frequently used hypnotics worldwide, but associations with serious adverse effects such as motor vehicle collisions have been reported. The objective of this study was to evaluate the association of fatal motor vehicle collisions with a prescription for zolpidem, considering the context of the motor vehicle collisions. We conducted a case-crossover study, where each case served as its own control, by linking data about fatal motor vehicle collisions from the Korean Road Traffic Authority between 2010 and 2014 with national health insurance data. The case period was defined as 1 day before the fatal motor vehicle collisions, and was matched to four control periods at 90-day intervals. Conditional logistic regression was performed to calculate the odds ratio for fatal motor vehicle collisions associated with zolpidem exposure, and odds ratios were adjusted for time-varying exposure to confounding medications. A stratified analysis was performed by age group (younger than 65 years or not), the Charlson Comorbidity Index, and whether patients were new zolpidem users. Among the 714 subjects, the adjusted odds ratio for a fatal motor vehicle collision associated with a prescription for zolpidem the previous day was 1.48 (95% confidence interval 1.06-2.07). After stratification, a significantly increased risk was observed in subjects with a high Charlson Comorbidity Index (odds ratio 1.81; 95% confidence interval 1.16-2.84), the younger age group (odds ratio: 1.62; 95% confidence interval 1.03-2.56), and new zolpidem users (odds ratio 2.37; 95% confidence interval 1.40-4.00). A prescription for zolpidem on the previous day was significantly related to an increased risk of fatal motor vehicle collisions in this population-based case-crossover study.
Franco Monsreal, José; Tun Cobos, Miriam Del Ruby; Hernández Gómez, José Ricardo; Serralta Peraza, Lidia Esther Del Socorro
2018-01-17
Low birth weight has been an enigma for science over time. There have been many researches on its causes and its effects. Low birth weight is an indicator that predicts the probability of a child surviving. In fact, there is an exponential relationship between weight deficit, gestational age, and perinatal mortality. Multiple logistic regression is one of the most expressive and versatile statistical instruments available for the analysis of data in both clinical and epidemiology settings, as well as in public health. To assess in a multivariate fashion the importance of 17 independent variables in low birth weight (dependent variable) of children born in the Mayan municipality of José María Morelos, Quintana Roo, Mexico. Analytical observational epidemiological cohort study with retrospective temporality. Births that met the inclusion criteria occurred in the "Hospital Integral Jose Maria Morelos" of the Ministry of Health corresponding to the Maya municipality of Jose Maria Morelos during the period from August 1, 2014 to July 31, 2015. The total number of newborns recorded was 1,147; 84 of which (7.32%) had low birth weight. To estimate the independent association between the explanatory variables (potential risk factors) and the response variable, a multiple logistic regression analysis was performed using the IBM SPSS Statistics 22 software. In ascending numerical order values of odds ratio > 1 indicated the positive contribution of explanatory variables or possible risk factors: "unmarried" marital status (1.076, 95% confidence interval: 0.550 to 2.104); age at menarche ≤ 12 years (1.08, 95% confidence interval: 0.64 to 1.84); history of abortion(s) (1.14, 95% confidence interval: 0.44 to 2.93); maternal weight < 50 kg (1.51, 95% confidence interval: 0.83 to 2.76); number of prenatal consultations ≤ 5 (1.86, 95% confidence interval: 0.94 to 3.66); maternal age ≥ 36 years (3.5, 95% confidence interval: 0.40 to 30.47); maternal age ≤ 19 years (3.59, 95% confidence interval: 0.43 to 29.87); number of deliveries = 1 (3.86, 95% confidence interval: 0.33 to 44.85); personal pathological history (4.78, 95% confidence interval: 2.16 to 10.59); pathological obstetric history (5.01, 95% confidence interval: 1.66 to 15.18); maternal height < 150 cm (5.16, 95% confidence interval: 3.08 to 8.65); number of births ≥ 5 (5.99, 95% confidence interval: 0.51 to 69.99); and smoking (15.63, 95% confidence interval: 1.07 to 227.97). Four of the independent variables (personal pathological history, obstetric pathological history, maternal stature <150 centimeters and smoking) showed a significant positive contribution, thus they can be considered as clear risk factors for low birth weight. The use of the logistic regression model in the Mayan municipality of José María Morelos, will allow estimating the probability of low birth weight for each pregnant woman in the future, which will be useful for the health authorities of the region.
Howard, George; McClure, Leslie A; Moy, Claudia S; Howard, Virginia J; Judd, Suzanne E; Yuan, Ya; Long, D Leann; Muntner, Paul; Safford, Monika M; Kleindorfer, Dawn O
2017-07-01
The standard for stroke risk stratification is the Framingham Stroke Risk Function (FSRF), an equation requiring an examination for blood pressure assessment, venipuncture for glucose assessment, and ECG to determine atrial fibrillation and heart disease. We assess a self-reported stroke risk function (SRSRF) to stratify stroke risk in comparison to the FSRF. Participants from the REGARDS study (Reasons for Geographic and Racial Differences in Stroke) were evaluated at baseline and followed for incident stroke. The FSRF was calculated using directly assessed stroke risk factors. The SRSRF was calculated from 13 self-reported questions to exclude those with prevalent stroke and assess stroke risk. Proportional hazards analysis was used to assess incident stroke risk using the FSRF and SRSRF. Over an average 8.2-year follow-up, 939 of 23 983 participants had a stroke. The FSRF and SRSRF produced highly correlated risk scores ( r Spearman =0.852; 95% confidence interval, 0.849-0.856); however, the SRSRF had higher discrimination of stroke risk than the FSRF (c SRSRF =0.7266; 95% confidence interval, 0.7076-0.7457; c FSRF =0.7075; 95% confidence interval, 0.6877-0.7273; P =0.0038). The 10-year stroke risk in the highest decile of predicted risk was 11.1% for the FSRF and 13.4% for the SRSRF. A simple self-reported questionnaire can be used to identify those at high risk for stroke better than the gold standard FSRF. This instrument can be used clinically to easily identify individuals at high risk for stroke and also scientifically to identify a subpopulation enriched for stroke risk. © 2017 American Heart Association, Inc.
Audit of lymphadenectomy in lung cancer resections using a specimen collection kit and checklist.
Osarogiagbon, Raymond U; Sareen, Srishti; Eke, Ransome; Yu, Xinhua; McHugh, Laura M; Kernstine, Kemp H; Putnam, Joe B; Robbins, Edward T
2015-02-01
Audits of operative summaries and pathology reports reveal wide discordance in identifying the extent of lymphadenectomy performed (the communication gap). We tested the ability of a prelabeled lymph node specimen collection kit and checklist to narrow the communication gap between operating surgeons, pathologists, and auditors of surgeons' operation notes. We conducted a prospective single cohort study of lung cancer resections performed with a lymph node collection kit from November 2010 to January 2013. We used the kappa statistic to compare surgeon claims on a checklist of lymph node stations harvested intraoperatively with pathology reports and an independent audit of surgeons' operative summaries. Lymph node collection procedures were classified into four groups based on the anatomic origin of resected lymph nodes: mediastinal lymph node dissection, systematic sampling, random sampling, and no sampling. From the pathology reports, 73% of 160 resections had a mediastinal lymph node dissection or systematic sampling procedure, 27% had random sampling. The concordance with surgeon claims was 80% (kappa statistic 0.69, 95% confidence interval: 0.60 to 0.79). Concordance between independent audits of the operation notes and either the pathology report (kappa 0.14, 95% confidence interval: 0.04 to 0.23) or surgeon claims (kappa 0.09, 95% confidence interval: 0.03 to 0.22) was poor. A prelabeled specimen collection kit and checklist significantly narrowed the communication gap between surgeons and pathologists in identifying the extent of lymphadenectomy. Audit of surgeons' operation notes did not accurately reflect the procedure performed, bringing its value for quality improvement work into question. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
H. T. Schreuder; M. S. Williams
2000-01-01
In simulation sampling from forest populations using sample sizes of 20, 40, and 60 plots respectively, confidence intervals based on the bootstrap (accelerated, percentile, and t-distribution based) were calculated and compared with those based on the classical t confidence intervals for mapped populations and subdomains within those populations. A 68.1 ha mapped...
Rea, Corinna J.; Smith, Renata L.; Taveras, Elsie M.
2016-01-01
Study Objectives: To examine the extent to which parent health behaviors and parenting practices are associated with school-age children's sleep duration. Methods: We surveyed 790 parents of children, aged 6 to 12 y, who had a body mass index (BMI) ≥ 90th percentile and were participating in a randomized controlled obesity trial. The main exposures were parent sleep duration, screen time and physical activity, parental limits placed on child TV viewing time and TV content, and parents' confidence regarding their ability to help their child get enough sleep. The primary outcome was child sleep duration. We used linear regression models to examine associations of parent behaviors and parenting practices with child sleep duration. Results: On average, children slept 9.2 h per night, whereas parents slept 6.9 h. Parents reported having an average of 1.9 h of screen time per day and 0.6 h of physical activity. There were 57.3% of parents who reported feeling very/extremely confident that they could help their child get enough sleep. In adjusted multivariate analyses, child sleep duration was 0.09 h/day (95% confidence interval: 0.03, 0.15) longer for each 1-h increment in parent sleep duration. Additionally, children whose parents reported being very/extremely confident they could help their child get age-appropriate sleep duration slept 0.67 h/day longer (95% confidence interval: 0.54, 0.81) than those whose parents were not/somewhat confident. Conclusions: Educating parents about their own sleep health and enhancing parent confidence to help their children get enough sleep are potential areas of intervention to increase child sleep duration. Citation: Rea CJ, Smith RL, Taveras EM. Associations of parent health behaviors and parenting practices with sleep duration in overweight and obese children. J Clin Sleep Med 2016;12(11):1493–1498. PMID:27655464
Mehta, Ambar; Xu, Tim; Hutfless, Susan; Makary, Martin A; Sinno, Abdulrahman K; Tanner, Edward J; Stone, Rebecca L; Wang, Karen; Fader, Amanda N
2017-05-01
Hysterectomy is among the most common major surgical procedures performed in women. Approximately 450,000 hysterectomy procedures are performed each year in the United States for benign indications. However, little is known regarding contemporary US hysterectomy trends for women with benign disease with respect to operative technique and perioperative complications, and the association between these 2 factors with patient, surgeon, and hospital characteristics. We sought to describe contemporary hysterectomy trends and explore associations between patient, surgeon, and hospital characteristics with surgical approach and perioperative complications. Hysterectomies performed for benign indications by general gynecologists from July 2012 through September 2014 were analyzed in the all-payer Maryland Health Services Cost Review Commission database. We excluded hysterectomies performed by gynecologic oncologists, reproductive endocrinologists, and female pelvic medicine and reconstructive surgeons. We included both open hysterectomies and those performed by minimally invasive surgery, which included vaginal hysterectomies. Perioperative complications were defined using the Agency for Healthcare Research and Quality patient safety indicators. Surgeon hysterectomy volume during the 2-year study period was analyzed (0-5 cases annually = very low, 6-10 = low, 11-20 = medium, and ≥21 = high). We utilized logistic regression and negative binomial regression to identify patient, surgeon, and hospital characteristics associated with minimally invasive surgery utilization and perioperative complications, respectively. A total of 5660 hospitalizations were identified during the study period. Most patients (61.5%) had an open hysterectomy; 38.5% underwent a minimally invasive surgery procedure (25.1% robotic, 46.6% laparoscopic, 28.3% vaginal). Most surgeons (68.2%) were very low- or low-volume surgeons. Factors associated with a lower likelihood of undergoing minimally invasive surgery included older patient age (reference 45-64 years; 20-44 years: adjusted odds ratio, 1.16; 95% confidence interval, 1.05-1.28), black race (reference white; adjusted odds ratio, 0.70; 95% confidence interval, 0.63-0.78), Hispanic ethnicity (adjusted odds ratio, 0.62; 95% confidence interval, 0.48-0.80), smaller hospital (reference large; small: adjusted odds ratio, 0.26; 95% confidence interval, 0.15-0.45; medium: adjusted odds ratio, 0.87; 95% confidence interval, 0.79-0.96), medium hospital hysterectomy volume (reference ≥200 hysterectomies; 100-200: adjusted odds ratio, 0.78; 95% confidence interval, 0.71-0.87), and medium vs high surgeon volume (reference high; medium: adjusted odds ratio, 0.87; 95% confidence interval, 0.78-0.97). Complications occurred in 25.8% of open and 8.2% of minimally invasive hysterectomies (P < .0001). Minimally invasive hysterectomy (adjusted odds ratio, 0.22; 95% confidence interval, 0.17-0.27) and large hysterectomy volume hospitals (reference ≥200 hysterectomies; 1-100: adjusted odds ratio, 2.26; 95% confidence interval, 1.60-3.20; 101-200: adjusted odds ratio, 1.63; 95% confidence interval, 1.23-2.16) were associated with fewer complications, while patient payer, including Medicare (reference private; adjusted odds ratio, 1.86; 95% confidence interval, 1.33-2.61), Medicaid (adjusted odds ratio, 1.63; 95% confidence interval, 1.30-2.04), and self-pay status (adjusted odds ratio, 2.41; 95% confidence interval, 1.40-4.12), and very-low and low surgeon hysterectomy volume (reference ≥21 cases; 1-5 cases: adjusted odds ratio, 1.73; 95% confidence interval, 1.22-2.47; 6-10 cases: adjusted odds ratio, 1.60; 95% confidence interval, 1.11-2.23) were associated with perioperative complications. Use of minimally invasive hysterectomy for benign indications remains variable, with most patients undergoing open, more morbid procedures. Older and black patients and smaller hospitals are associated with open hysterectomy. Patient race and payer status, hysterectomy approach, and surgeon volume were associated with perioperative complications. Hysterectomies performed for benign indications by high-volume surgeons or by minimally invasive techniques may represent an opportunity to reduce preventable harm. Copyright © 2017 Elsevier Inc. All rights reserved.
Hamer, Mark; Sabia, Severine; Batty, G David; Shipley, Martin J; Tabák, Adam G; Singh-Manoux, Archana; Kivimaki, Mika
2012-08-21
Inflammatory processes are putative mechanisms underlying the cardioprotective effects of physical activity. An inverse association between physical activity and inflammation has been demonstrated, but no long-term prospective data are available. We therefore examined the association between physical activity and inflammatory markers over a 10-year follow-up period. Participants were 4289 men and women (mean age, 49.2 years) from the Whitehall II cohort study. Self-reported physical activity and inflammatory markers (serum high-sensitivity C-reactive protein and interleukin-6) were measured at baseline (1991) and follow-up (2002). Forty-nine percent of the participants adhered to standard physical activity recommendations for cardiovascular health (2.5 h/wk moderate to vigorous physical activity) across all assessments. Physically active participants at baseline had lower C-reactive protein and interleukin-6 levels, and this difference remained stable over time. Compared with participants who rarely adhered to physical activity guidelines over the 10-year follow-up, the high-adherence group displayed lower log(e) C-reactive protein (β=-0.07; 95% confidence interval, -0.12 to -0.02) and log(e) interleukin-6 (β=-0.07; 95% confidence interval, -0.10 to -0.03) at follow-up after adjustment for a range of covariates. Compared with participants who remained stable, those who reported an increase in physical activity of at least 2.5 h/wk displayed lower log(e) C-reactive protein (β coefficient=-0.05; 95% confidence interval, -0.10 to -0.001) and log(e) interleukin-6 (β coefficient=-0.06; 95% confidence interval, -0.09 to -0.03) at follow-up. Regular physical activity is associated with lower markers of inflammation over 10 years of follow-up and thus may be important in preventing the proinflammatory state seen with aging.
Muscedere, John; Rewa, Oleksa; McKechnie, Kyle; Jiang, Xuran; Laporta, Denny; Heyland, Daren K
2011-08-01
Aspiration of secretions containing bacterial pathogens into the lower respiratory tract is the main cause of ventilator-associated pneumonia. Endotracheal tubes with subglottic secretion drainage can potentially reduce this and, therefore, the incidence of ventilator-associated pneumonia. New evidence on subglottic secretion drainage as a preventive measure for ventilator-associated pneumonia has been recently published and to consider the evidence in totality, we conducted an updated systematic review and meta-analysis. We searched computerized databases, reference lists, and personal files. We included randomized clinical trials of mechanically ventilated patients comparing standard endotracheal tubes to those with subglottic secretion drainage and reporting on the occurrence of ventilator-associated pneumonia. Studies were meta-analyzed for the primary outcome of ventilator-associated pneumonia and secondary clinical outcomes. We identified 13 randomized clinical trials that met the inclusion criteria with a total of 2442 randomized patients. Of the 13 studies, 12 reported a reduction in ventilator-associated pneumonia rates in the subglottic secretion drainage arm; in meta-analysis, the overall risk ratio for ventilator-associated pneumonia was 0.55 (95% confidence interval, 0.46-0.66; p < .00001) with no heterogeneity (I = 0%). The use of subglottic secretion drainage was associated with reduced intensive care unit length of stay (-1.52 days; 95% confidence interval, -2.94 to -0.11; p = .03); decreased duration of mechanically ventilated (-1.08 days; 95% confidence interval, -2.04 to -0.12; p = .03), and increased time to first episode of ventilator-associated pneumonia (2.66 days; 95% confidence interval, 1.06-4.26; p = .001). There was no effect on adverse events or on hospital or intensive care unit mortality. In those at risk for ventilator-associated pneumonia, the use of endotracheal tubes with subglottic secretion drainage is effective for the prevention of ventilator-associated pneumonia and may be associated with reduced duration of mechanical ventilation and intensive care unit length of stay.
Lindau, Stacy Tessler; Abramsohn, Emily M; Bueno, Héctor; D'Onofrio, Gail; Lichtman, Judith H; Lorenze, Nancy P; Mehta Sanghani, Rupa; Spatz, Erica S; Spertus, John A; Strait, Kelly; Wroblewski, Kristen; Zhou, Shengfan; Krumholz, Harlan M
2014-12-23
United States and European cardiovascular society guidelines recommend physicians counsel patients about resuming sexual activity after acute myocardial infarction (AMI), but little is known about patients' experience with counseling about sexual activity after AMI. The prospective, longitudinal Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients (VIRGO) study, conducted at 127 hospitals in the United States and Spain, was designed, in part, to evaluate gender differences in baseline sexual activity, function, and patient experience with physician counseling about sexual activity after an AMI. This study used baseline and 1-month data collected from the 2:1 sample of women (N=2349) and men (N=1152) ages 18 to 55 years with AMI. Median age was 48 years. Among those who reported discussing sexual activity with a physician in the month after AMI (12% of women, 19% of men), 68% were given restrictions: limit sex (35%), take a more passive role (26%), and/or keep the heart rate down (23%). In risk-adjusted analyses, factors associated with not discussing sexual activity with a physician included female gender (relative risk, 1.07; 95% confidence interval, 1.03-1.11), age (relative risk, 1.05 per 10 years; 95% confidence interval, 1.02-1.08), and sexual inactivity at baseline (relative risk, 1.11; 95% confidence interval, 1.08-1.15). Among patients who received counseling, women in Spain were significantly more likely to be given restrictions than U.S. women (relative risk; 1.36, 95% confidence interval, 1.11-1.66). Very few patients reported counseling for sexual activity after AMI. Those who did were commonly given restrictions not supported by evidence or guidelines. http://www.clinicaltrials.gov. Unique identifier: NCT00597922. © 2014 American Heart Association, Inc.
Janes, Francesco; Gigli, Gian Luigi; D'Anna, Lucio; Cancelli, Iacopo; Perelli, Anna; Canal, Giessica; Russo, Valentina; Zanchettin, Barbara; Valente, Mariarosaria
2013-10-01
Stroke incidence in high-income countries is reported to decrease, and new data on stroke incidence and outcome are needed to design stroke services and to ameliorate stroke management. This study is part of a two-year prospective community-based registry of all cerebrovascular events in the district of Udine (153,312 inhabitants), Friuli-Venezia Giulia region, northeast of Italy, between 1 April 2007 and 31 March 2009. Overlapping sources for case finding were used, combining hot and cold pursuit. We identified 784 stroke cases, 640 (81.6%) incident. The crude overall annual incidence rate per 100,000 residents was 256 (95% confidence interval 241-271) for all strokes and 209 (95% confidence interval 195-223) for first-ever strokes. Incidence rate for first-ever strokes was 181 (95% confidence interval 155-211) after adjustment to the 2007 Italian population and 104 (95% confidence interval 88-122) compared with the European standard population. Incidence rates for first-ever strokes was 215 (196-235) for women, 202 (183-223) for men. Crude annual incidence rates per 100,000 population were 167 (153-178) for ischemic stroke, 31 (26-37) for intracerebral hemorrhage, 8.1 (5.7-11.4) for sub-arachnoid hemorrhage, and 4.6 (2.8-7.1) for undetermined stroke. Overall case fatality rates for first-ever stroke were 20.6% at 28 days and 30.2% at 180 days. Our study shows incidence rates higher than previously reported in our region but not supporting the view of higher incidence rates in Northern than in Southern Italy. Results contribute to time-trends analysis on epidemiology, useful for dimensioning services in Italy and show the persistence of a gap between the outcome of stroke in Italy and that of the best performing European countries, urging to adopt better stroke management plans. © 2013 The Authors. International Journal of Stroke © 2013 World Stroke Organization.
Tsivgoulis, Georgios; Zand, Ramin; Katsanos, Aristeidis H; Goyal, Nitin; Uchino, Ken; Chang, Jason; Dardiotis, Efthimios; Putaala, Jukka; Alexandrov, Anne W; Malkoff, Marc D; Alexandrov, Andrei V
2015-05-01
Shortening door-to-needle time may lead to inadvertent intravenous thrombolysis (IVT) administration in stroke mimics (SMs). We sought to determine the safety of IVT in SMs using prospective, single-center data and by conducting a comprehensive meta-analysis of reported case-series. We prospectively analyzed consecutive IVT-treated patients during a 5-year period at a tertiary care stroke center. A systematic review and meta-analysis of case-series reporting safety of IVT in SMs and confirmed acute ischemic stroke were conducted. Symptomatic intracerebral hemorrhage was defined as imaging evidence of ICH with an National Institutes of Health Stroke scale increase of ≥4 points. Favorable functional outcome at hospital discharge was defined as a modified Rankin Scale score of 0 to 1. Of 516 consecutive IVT patients at our tertiary care center (50% men; mean age, 60±14 years; median National Institutes of Health Stroke scale, 11; range, 3-22), SMs comprised 75 cases. Symptomatic intracerebral hemorrhage occurred in 1 patient, whereas we documented no cases of orolingual edema or major extracranial hemorrhagic complications. In meta-analysis of 9 studies (8942 IVT-treated patients), the pooled rates of symptomatic intracerebral hemorrhage and orolingual edema among 392 patients with SM treated with IVT were 0.5% (95% confidence interval, 0%-2%) and 0.3% (95% confidence interval, 0%-2%), respectively. Patients with SM were found to have a significantly lower risk for symptomatic intracerebral hemorrhage compared with patients with acute ischemic stroke (risk ratio=0.33; 95% confidence interval, 0.14-0.77; P=0.010), with no evidence of heterogeneity or publication bias. Favorable functional outcome was almost 3-fold higher in patients with SM in comparison with patients with acute ischemic stroke (risk ratio=2.78; 95% confidence interval, 2.07-3.73; P<0.00001). Our prospective, single-center experience coupled with the findings of the comprehensive meta-analysis underscores the safety of IVT in SM. © 2015 American Heart Association, Inc.
Statistical Applications in Two Leading Educational Administration Journals
ERIC Educational Resources Information Center
Byrd, Jimmy; Eddy, Colleen
2009-01-01
Purpose: The purpose of this study was to review research published by "Journal of Educational Administration (JEA)" and the "Educational Administration Quarterly (EAQ)" over the past ten years to examine the type of research reported and to determine if confidence intervals and effect sizes were being reported as recommended by the American…
Hassan, Hadeel; Pinches, Anne; Picton, Susan V; Phillips, Robert S
2017-10-01
Diagnosis of a pediatric high grade brain stem glioma is devastating with dismal outcomes. This systematic review and meta-analysis was undertaken to determine the survival rates and assess potential prognostic factors including selected interventions. Studies included involved pediatric participants with high grade brain stem gliomas diagnosed by magnetic resonance imaging or biopsy reporting overall survival rates. Meta-analysis was undertaken using a binomial random effects model. Sixty-five studies (2336 participants) were included. Meta-analysis showed 1 year overall survival (OS) of 41% (95% confidence interval (CI) 38-44%, I-sq 52%, 2083 participants), 2 year OS of 15.3% (95% confidence interval 12-20%, I-sq 73.1%, 1329 participants) and 3 year OS of 7.3% (95% confidence interval 5.2-10%, I-sq 26%, 584 participants). Meta-analyses of median overall survival results was not possible due to the lack of reported measures of variance. Subgroup analysis comparing date of study, classification of tumor, use of temozolomide, non-standard interventions or phase 1/2 versus other studies demonstrated no difference in survival outcomes. There was insufficient data to undertake subgroup meta-analysis of patient age, duration of symptoms, K27M histone mutations and AVCR1 mutations. Survival outcomes of high grade brain stem gliomas have remained very poor, and do not clearly vary according to classification, phase of study or use of different therapeutic interventions. Future studies should harmonize outcome and prognostic variable reporting to enable accurate meta-analysis and better exploration of prognosis.
Miyawaki, Atsushi; Toyokawa, Satoshi; Inoue, Kazuo; Miyoshi, Yuji; Kobayashi, Yasuki
2016-01-01
Aims The purpose of this study was to examine whether periodontitis is associated with incident type 2 diabetes in a Japanese male worker cohort. Methods The study participants were Japanese men, aged 36–55 years, without diabetes. Data were extracted from the MY Health Up study, consisting of self-administered questionnaire surveys at baseline and following annual health examinations for an insurance company in Japan. The oral health status of the participants was classified by two self-reported indicators: (1) gingival hemorrhage and (2) tooth loosening. Type 2 diabetes incidence was determined by self-reporting or blood test data. Modified Poisson regression approach was used to estimate the relative risks and the 95% confidence intervals of incident diabetes with periodontitis. Covariates included age, body mass index, family history of diabetes, hypertension, current smoking habits, alcohol use, dyslipidemia, and exercise habits. Results Of the 2895 candidates identified at baseline in 2004, 2469 men were eligible for follow-up analysis, 133 of whom were diagnosed with diabetes during the 5-year follow-up period. Tooth loosening was associated with incident diabetes [adjusted relative risk = 1.73, 95% confidence interval = 1.14–2.64] after adjusting for other confounding factors. Gingival hemorrhage displayed a similar trend but was not significantly associated with incident diabetes [adjusted relative risk = 1.32, 95% confidence interval = 0.95–1.85]. Conclusions Tooth loosening is an independent predictor of incident type 2 diabetes in Japanese men. PMID:27115749
Ferrucci, Leah M; Vogel, Rachel Isaksson; Cartmel, Brenda; Lazovich, DeAnn; Mayne, Susan T
2014-11-01
Indoor tanning increases skin cancer risk. Beyond early research describing melanoma and sun lamps, few recent reports describe where individuals indoor tan and whether skin cancer risk varies by location (business, home-based). We sought to assess where individuals tanned indoors and skin cancer risk by tanning device location. Multivariate logistic regression was conducted in 2 US case-control studies of melanoma (1161 cases, 1083 controls, ages 25-59 years) and early-onset basal cell carcinoma (375 cases, 382 controls, age<40 years) conducted between 2004 and 2010. Most indoor tanners (86.4%-95.1%), especially younger individuals, tanned exclusively in businesses. Persons who used indoor tanning exclusively in businesses were at increased risk of melanoma (odds ratio 1.82, 95% confidence interval 1.47-2.26) and basal cell carcinoma (odds ratio 1.69, 95% confidence interval 1.15-2.48) compared with non-users. Melanoma risk was also increased in the small number who reported tanning indoors only at home relative to non-users (odds ratio 4.14, 95% confidence interval 1.75-9.78); 67.6% used sun lamps. Self-reported tanning and potential recall bias are limitations. Business-only tanning, despite claims of "safe" tanning, was positively associated with a significant risk of melanoma and basal cell carcinoma. Home tanning was uncommon and mostly from sun lamps, which were rarely used by younger participants. Regardless of location, indoor tanning was associated with increased risk of skin cancer. Copyright © 2014 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.
Biglands, John D; Ibraheem, Montasir; Magee, Derek R; Radjenovic, Aleksandra; Plein, Sven; Greenwood, John P
2018-05-01
This study sought to compare the diagnostic accuracy of visual and quantitative analyses of myocardial perfusion cardiovascular magnetic resonance against a reference standard of quantitative coronary angiography. Visual analysis of perfusion cardiovascular magnetic resonance studies for assessing myocardial perfusion has been shown to have high diagnostic accuracy for coronary artery disease. However, only a few small studies have assessed the diagnostic accuracy of quantitative myocardial perfusion. This retrospective study included 128 patients randomly selected from the CE-MARC (Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease) study population such that the distribution of risk factors and disease status was proportionate to the full population. Visual analysis results of cardiovascular magnetic resonance perfusion images, by consensus of 2 expert readers, were taken from the original study reports. Quantitative myocardial blood flow estimates were obtained using Fermi-constrained deconvolution. The reference standard for myocardial ischemia was a quantitative coronary x-ray angiogram stenosis severity of ≥70% diameter in any coronary artery of >2 mm diameter, or ≥50% in the left main stem. Diagnostic performance was calculated using receiver-operating characteristic curve analysis. The area under the curve for visual analysis was 0.88 (95% confidence interval: 0.81 to 0.95) with a sensitivity of 81.0% (95% confidence interval: 69.1% to 92.8%) and specificity of 86.0% (95% confidence interval: 78.7% to 93.4%). For quantitative stress myocardial blood flow the area under the curve was 0.89 (95% confidence interval: 0.83 to 0.96) with a sensitivity of 87.5% (95% confidence interval: 77.3% to 97.7%) and specificity of 84.5% (95% confidence interval: 76.8% to 92.3%). There was no statistically significant difference between the diagnostic performance of quantitative and visual analyses (p = 0.72). Incorporating rest myocardial blood flow values to generate a myocardial perfusion reserve did not significantly increase the quantitative analysis area under the curve (p = 0.79). Quantitative perfusion has a high diagnostic accuracy for detecting coronary artery disease but is not superior to visual analysis. The incorporation of rest perfusion imaging does not improve diagnostic accuracy in quantitative perfusion analysis. Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Ma, Chenhan; Avenell, Alison; Bolland, Mark; Hudson, Jemma; Stewart, Fiona; Robertson, Clare; Sharma, Pawana; Fraser, Cynthia; MacLennan, Graeme
2017-11-14
Objective To assess whether weight loss interventions for adults with obesity affect all cause, cardiovascular, and cancer mortality, cardiovascular disease, cancer, and body weight. Design Systematic review and meta-analysis of randomised controlled trials (RCTs) using random effects, estimating risk ratios, and mean differences. Heterogeneity investigated using Cochran's Q and I 2 statistics. Quality of evidence assessed by GRADE criteria. Data sources Medline, Embase, the Cochrane Central Register of Controlled Trials, and full texts in our trials' registry for data not evident in databases. Authors were contacted for unpublished data. Eligibility criteria for selecting studies RCTs of dietary interventions targeting weight loss, with or without exercise advice or programmes, for adults with obesity and follow-up ≥1 year. Results 54 RCTs with 30 206 participants were identified. All but one trial evaluated low fat, weight reducing diets. For the primary outcome, high quality evidence showed that weight loss interventions decrease all cause mortality (34 trials, 685 events; risk ratio 0.82, 95% confidence interval 0.71 to 0.95), with six fewer deaths per 1000 participants (95% confidence interval two to 10). For other primary outcomes moderate quality evidence showed an effect on cardiovascular mortality (eight trials, 134 events; risk ratio 0.93, 95% confidence interval 0.67 to 1.31), and very low quality evidence showed an effect on cancer mortality (eight trials, 34 events; risk ratio 0.58, 95% confidence interval 0.30 to 1.11). Twenty four trials (15 176 participants) reported high quality evidence on participants developing new cardiovascular events (1043 events; risk ratio 0.93, 95% confidence interval 0.83 to 1.04). Nineteen trials (6330 participants) provided very low quality evidence on participants developing new cancers (103 events; risk ratio 0.92, 95% confidence interval 0.63 to 1.36). Conclusions Weight reducing diets, usually low in fat and saturated fat, with or without exercise advice or programmes, may reduce premature all cause mortality in adults with obesity. Systematic review registration PROSPERO CRD42016033217. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Prospective study of physical activity and risk of postmenopausal breast cancer
Leitzmann, Michael F; Moore, Steven C; Peters, Tricia M; Lacey, James V; Schatzkin, Arthur; Schairer, Catherine; Brinton, Louise A; Albanes, Demetrius
2008-01-01
Introduction To prospectively examine the relation of total, vigorous and non-vigorous physical activity to postmenopausal breast cancer risk. Methods We studied 32,269 women enrolled in the Breast Cancer Detection Demonstration Project Follow-up Study. Usual physical activity (including household, occupational and leisure activities) throughout the previous year was assessed at baseline using a self-administered questionnaire. Postmenopausal breast cancer cases were identified through self-reports, death certificates and linkage to state cancer registries. A Cox proportional hazards regression was used to estimate the relative risk and 95% confidence intervals of postmenopausal breast cancer associated with physical activity. Results During 269,792 person-years of follow-up from 1987 to 1998, 1506 new incident cases of postmenopausal breast cancer were ascertained. After adjusting for potential risk factors of breast cancer, a weak inverse association between total physical activity and postmenopausal breast cancer was suggested (relative risk comparing extreme quintiles = 0.87; 95% confidence interval = 0.74 to 1.02; p for trend = 0.21). That relation was almost entirely contributed by vigorous activity (relative risk comparing extreme categories = 0.87; 95% confidence interval = 0.74 to 1.02; p for trend = 0.08). The inverse association with vigorous activity was limited to women who were lean (ie, body mass index <25.0 kg/m2: relative risk = 0.68; 95% confidence interval = 0.54 to 0.85). In contrast, no association with vigorous activity was noted among women who were overweight or obese (ie, body mass index ≥ 25.0 kg/m2: relative risk = 1.18; 95% confidence interval = 0.93 to 1.49; p for interaction = 0.008). Non-vigorous activity showed no relation to breast cancer (relative risk comparing extreme quintiles = 1.02; 95% confidence interval = 0.87 to 1.19; p for trend = 0.86). The physical activity and breast cancer relation was not specific to a certain hormone receptor subtype. Conclusions In this cohort of postmenopausal women, breast cancer risk reduction appeared to be limited to vigorous forms of activity; it was apparent among normal weight women but not overweight women, and the relation did not vary by hormone receptor status. Our findings suggest that physical activity acts through underlying biological mechanisms that are independent of body weight control. PMID:18976449
Opioid Analgesics and Adverse Outcomes among Hemodialysis Patients.
Ishida, Julie H; McCulloch, Charles E; Steinman, Michael A; Grimes, Barbara A; Johansen, Kirsten L
2018-05-07
Patients on hemodialysis frequently experience pain and may be particularly vulnerable to opioid-related complications. However, data evaluating the risks of opioid use in patients on hemodialysis are limited. Using the US Renal Data System, we conducted a cohort study evaluating the association between opioid use (modeled as a time-varying exposure and expressed in standardized oral morphine equivalents) and time to first emergency room visit or hospitalization for altered mental status, fall, and fracture among 140,899 Medicare-covered adults receiving hemodialysis in 2011. We evaluated risk according to average daily total opioid dose (>60 mg, ≤60 mg, and per 60-mg dose increment) and specific agents (per 60-mg dose increment). The median age was 61 years old, 52% were men, and 50% were white. Sixty-four percent received opioids, and 17% had an episode of altered mental status (15,658 events), fall (7646 events), or fracture (4151 events) in 2011. Opioid use was associated with risk for all outcomes in a dose-dependent manner: altered mental status (lower dose: hazard ratio, 1.28; 95% confidence interval, 1.23 to 1.34; higher dose: hazard ratio, 1.67; 95% confidence interval, 1.56 to 1.78; hazard ratio, 1.29 per 60 mg; 95% confidence interval, 1.26 to 1.33), fall (lower dose: hazard ratio, 1.28; 95% confidence interval, 1.21 to 1.36; higher dose: hazard ratio, 1.45; 95% confidence interval, 1.31 to 1.61; hazard ratio, 1.04 per 60 mg; 95% confidence interval, 1.03 to 1.05), and fracture (lower dose: hazard ratio, 1.44; 95% confidence interval, 1.33 to 1.56; higher dose: hazard ratio, 1.65; 95% confidence interval, 1.44 to 1.89; hazard ratio, 1.04 per 60 mg; 95% confidence interval, 1.04 to 1.05). All agents were associated with a significantly higher hazard of altered mental status, and several agents were associated with a significantly higher hazard of fall and fracture. Opioids were associated with adverse outcomes in patients on hemodialysis, and this risk was present even at lower dosing and for agents that guidelines have recommended for use. Copyright © 2018 by the American Society of Nephrology.
Pregnancy outcome in joint hypermobility syndrome and Ehlers-Danlos syndrome.
Sundelin, Heléne E K; Stephansson, Olof; Johansson, Kari; Ludvigsson, Jonas F
2017-01-01
An increased risk of preterm birth in women with joint hypermobility syndrome or Ehlers-Danlos syndrome is suspected. In this nationwide cohort study from 1997 through 2011, women with either joint hypermobility syndrome or Ehlers-Danlos syndrome or both disorders were identified through the Swedish Patient Register, and linked to the Medical Birth Register. Thereby, 314 singleton births to women with joint hypermobility syndrome/Ehlers-Danlos syndrome before delivery were identified. These births were compared with 1 247 864 singleton births to women without a diagnosis of joint hypermobility syndrome/Ehlers-Danlos syndrome. We used logistic regression, adjusted for maternal age, smoking, parity, and year of birth, to calculate adjusted odds ratios for adverse pregnancy outcomes. Maternal joint hypermobility syndrome/Ehlers-Danlos syndrome was not associated with any of our outcomes: preterm birth (adjusted odds ratio = 0.6, 95% confidence interval 0.3-1.2), preterm premature rupture of membranes (adjusted odds ratio = 0.8; 95% confidence interval 0.3-2.2), cesarean section (adjusted odds ratio = 0.9, 95% confidence interval 0.7-1.2), stillbirth (adjusted odds ratio = 1.1, 95% confidence interval 0.2-7.9), low Apgar score (adjusted odds ratio = 1.6, 95% confidence interval 0.7-3.6), small for gestational age (adjusted odds ratio = 0.9, 95% confidence interval 0.4-1.8) or large for gestational age (adjusted odds ratio = 1.2, 95% confidence interval 0.6-2.1). Examining only women with Ehlers-Danlos syndrome (n = 62), we found a higher risk of induction of labor (adjusted odds ratio = 2.6; 95% confidence interval 1.4-4.6) and amniotomy (adjusted odds ratio = 3.8; 95% confidence interval 2.0-7.1). No excess risks for adverse pregnancy outcome were seen in joint hypermobility syndrome. Women with joint hypermobility syndrome/Ehlers-Danlos syndrome do not seem to be at increased risk of adverse pregnancy outcome. © 2016 Nordic Federation of Societies of Obstetrics and Gynecology.
Rahn, Anne C; Backhus, Imke; Fuest, Franz; Riemann-Lorenz, Karin; Köpke, Sascha; van de Roemer, Adrianus; Mühlhauser, Ingrid; Heesen, Christoph
2016-09-20
Presentation of confidence intervals alongside information about treatment effects can support informed treatment choices in people with multiple sclerosis. We aimed to develop and pilot-test different written patient information materials explaining confidence intervals in people with relapsing-remitting multiple sclerosis. Further, a questionnaire on comprehension of confidence intervals was developed and piloted. We developed different patient information versions aiming to explain confidence intervals. We used an illustrative example to test three different approaches: (1) short version, (2) "average weight" version and (3) "worm prophylaxis" version. Interviews were conducted using think-aloud and teach-back approaches to test feasibility and analysed using qualitative content analysis. To assess comprehension of confidence intervals, a six-item multiple choice questionnaire was developed and tested in a pilot randomised controlled trial using the online survey software UNIPARK. Here, the average weight version (intervention group) was tested against a standard patient information version on confidence intervals (control group). People with multiple sclerosis were invited to take part using existing mailing-lists of people with multiple sclerosis in Germany and were randomised using the UNIPARK algorithm. Participants were blinded towards group allocation. Primary endpoint was comprehension of confidence intervals, assessed with the six-item multiple choice questionnaire with six points representing perfect knowledge. Feasibility of the patient information versions was tested with 16 people with multiple sclerosis. For the pilot randomised controlled trial, 64 people with multiple sclerosis were randomised (intervention group: n = 36; control group: n = 28). More questions were answered correctly in the intervention group compared to the control group (mean 4.8 vs 3.8, mean difference 1.1 (95 % CI 0.42-1.69), p = 0.002). The questionnaire's internal consistency was moderate (Cronbach's alpha = 0.56). The pilot-phase shows promising results concerning acceptability and feasibility. Pilot randomised controlled trial results indicate that the patient information is well understood and that knowledge gain on confidence intervals can be assessed with a set of six questions. German Clinical Trials Register: DRKS00008561 . Registered 8th of June 2015.
Ethnic Differences in Incidence and Outcomes of Childhood Nephrotic Syndrome.
Banh, Tonny H M; Hussain-Shamsy, Neesha; Patel, Viral; Vasilevska-Ristovska, Jovanka; Borges, Karlota; Sibbald, Cathryn; Lipszyc, Deborah; Brooke, Josefina; Geary, Denis; Langlois, Valerie; Reddon, Michele; Pearl, Rachel; Levin, Leo; Piekut, Monica; Licht, Christoph P B; Radhakrishnan, Seetha; Aitken-Menezes, Kimberly; Harvey, Elizabeth; Hebert, Diane; Piscione, Tino D; Parekh, Rulan S
2016-10-07
Ethnic differences in outcomes among children with nephrotic syndrome are unknown. We conducted a longitudinal study at a single regional pediatric center comparing ethnic differences in incidence from 2001 to 2011 census data and longitudinal outcomes, including relapse rates, time to first relapse, frequently relapsing disease, and use of cyclophosphamide. Among 711 children, 24% were European, 33% were South Asian, 10% were East/Southeast Asian, and 33% were of other origins. Over 10 years, the overall incidence increased from 1.99/100,000 to 4.71/100,000 among children ages 1-18 years old. In 2011, South Asians had a higher incidence rate ratio of 6.61 (95% confidence interval, 3.16 to 15.1) compared with Europeans. East/Southeast Asians had a similar incidence rate ratio (0.76; 95% confidence interval, 0.13 to 2.94) to Europeans. We determined outcomes in 455 children from the three largest ethnic groups with steroid-sensitive disease over a median of 4 years. South Asian and East/Southeast Asian children had significantly lower odds of frequently relapsing disease at 12 months (South Asian: adjusted odds ratio; 0.55; 95% confidence interval, 0.39 to 0.77; East/Southeast Asian: adjusted odds ratio; 0.42; 95% confidence interval, 0.34 to 0.51), fewer subsequent relapses (South Asian: adjusted odds ratio; 0.64; 95% confidence interval, 0.50 to 0.81; East/Southeast Asian: adjusted odds ratio; 0.47; 95% confidence interval, 0.24 to 0.91), lower risk of a first relapse (South Asian: adjusted hazard ratio, 0.74; 95% confidence interval, 0.67 to 0.83; East/Southeast Asian: adjusted hazard ratio, 0.65; 95% CI, 0.63 to 0.68), and lower use of cyclophosphamide (South Asian: adjusted hazard ratio, 0.82; 95% confidence interval, 0.53 to 1.28; East/Southeast Asian: adjusted hazard ratio, 0.54; 95% confidence interval, 0.41 to 0.71) compared with European children. Despite the higher incidence among South Asians, South and East/Southeast Asian children have significantly less complicated clinical outcomes compared with Europeans. Copyright © 2016 by the American Society of Nephrology.
Chow, Clara K; Jolly, Sanjit; Rao-Melacini, Purnima; Fox, Keith A A; Anand, Sonia S; Yusuf, Salim
2010-02-16
Although preventive drug therapy is a priority after acute coronary syndrome, less is known about adherence to behavioral recommendations. The aim of this study was to examine the influence of adherence to behavioral recommendations in the short term on risk of cardiovascular events. The study population included 18 809 patients from 41 countries enrolled in the Organization to Assess Strategies in Acute Ischemic Syndromes (OASIS) 5 randomized clinical trial. At the 30-day follow-up, patients reported adherence to diet, physical activity, and smoking cessation. Cardiovascular events (myocardial infarction, stroke, cardiovascular death) and all-cause mortality were documented to 6 months. About one third of smokers persisted in smoking. Adherence to neither diet nor exercise recommendations was reported by 28.5%, adherence to either diet or exercise by 41.6%, and adherence to both by 29.9%. In contrast, 96.1% of subjects reported antiplatelet use, 78.9% reported statin use, and 72.4% reported angiotensin-converting enzyme/angiotensin receptor blocker use. Quitting smoking was associated with a decreased risk of myocardial infarction compared with persistent smoking (odds ratio, 0.57; 95% confidence interval, 0.36 to 0.89). Diet and exercise adherence was associated with a decreased risk of myocardial infarction compared with nonadherence (odds ratio, 0.52; 95% confidence interval, 0.4 to 0.69). Patients who reported persistent smoking and nonadherence to diet and exercise had a 3.8-fold (95% confidence interval, 2.5 to 5.9) increased risk of myocardial infarction/stroke/death compared with never smokers who modified diet and exercise. Adherence to behavioral advice (diet, exercise, and smoking cessation) after acute coronary syndrome was associated with a substantially lower risk of recurrent cardiovascular events. These findings suggest that behavioral modification should be given priority similar to other preventive medications immediately after acute coronary syndrome. Clinical Trial Registration Information- URL: http://clinicaltrials.gov/ct2/show/NCT00139815. Unique identifier: NCT00139815.
Confidence intervals for correlations when data are not normal.
Bishara, Anthony J; Hittner, James B
2017-02-01
With nonnormal data, the typical confidence interval of the correlation (Fisher z') may be inaccurate. The literature has been unclear as to which of several alternative methods should be used instead, and how extreme a violation of normality is needed to justify an alternative. Through Monte Carlo simulation, 11 confidence interval methods were compared, including Fisher z', two Spearman rank-order methods, the Box-Cox transformation, rank-based inverse normal (RIN) transformation, and various bootstrap methods. Nonnormality often distorted the Fisher z' confidence interval-for example, leading to a 95 % confidence interval that had actual coverage as low as 68 %. Increasing the sample size sometimes worsened this problem. Inaccurate Fisher z' intervals could be predicted by a sample kurtosis of at least 2, an absolute sample skewness of at least 1, or significant violations of normality hypothesis tests. Only the Spearman rank-order and RIN transformation methods were universally robust to nonnormality. Among the bootstrap methods, an observed imposed bootstrap came closest to accurate coverage, though it often resulted in an overly long interval. The results suggest that sample nonnormality can justify avoidance of the Fisher z' interval in favor of a more robust alternative. R code for the relevant methods is provided in supplementary materials.
Shieh, G
2013-12-01
The use of effect sizes and associated confidence intervals in all empirical research has been strongly emphasized by journal publication guidelines. To help advance theory and practice in the social sciences, this article describes an improved procedure for constructing confidence intervals of the standardized mean difference effect size between two independent normal populations with unknown and possibly unequal variances. The presented approach has advantages over the existing formula in both theoretical justification and computational simplicity. In addition, simulation results show that the suggested one- and two-sided confidence intervals are more accurate in achieving the nominal coverage probability. The proposed estimation method provides a feasible alternative to the most commonly used measure of Cohen's d and the corresponding interval procedure when the assumption of homogeneous variances is not tenable. To further improve the potential applicability of the suggested methodology, the sample size procedures for precise interval estimation of the standardized mean difference are also delineated. The desired precision of a confidence interval is assessed with respect to the control of expected width and to the assurance probability of interval width within a designated value. Supplementary computer programs are developed to aid in the usefulness and implementation of the introduced techniques.
Braschel, Melissa C; Svec, Ivana; Darlington, Gerarda A; Donner, Allan
2016-04-01
Many investigators rely on previously published point estimates of the intraclass correlation coefficient rather than on their associated confidence intervals to determine the required size of a newly planned cluster randomized trial. Although confidence interval methods for the intraclass correlation coefficient that can be applied to community-based trials have been developed for a continuous outcome variable, fewer methods exist for a binary outcome variable. The aim of this study is to evaluate confidence interval methods for the intraclass correlation coefficient applied to binary outcomes in community intervention trials enrolling a small number of large clusters. Existing methods for confidence interval construction are examined and compared to a new ad hoc approach based on dividing clusters into a large number of smaller sub-clusters and subsequently applying existing methods to the resulting data. Monte Carlo simulation is used to assess the width and coverage of confidence intervals for the intraclass correlation coefficient based on Smith's large sample approximation of the standard error of the one-way analysis of variance estimator, an inverted modified Wald test for the Fleiss-Cuzick estimator, and intervals constructed using a bootstrap-t applied to a variance-stabilizing transformation of the intraclass correlation coefficient estimate. In addition, a new approach is applied in which clusters are randomly divided into a large number of smaller sub-clusters with the same methods applied to these data (with the exception of the bootstrap-t interval, which assumes large cluster sizes). These methods are also applied to a cluster randomized trial on adolescent tobacco use for illustration. When applied to a binary outcome variable in a small number of large clusters, existing confidence interval methods for the intraclass correlation coefficient provide poor coverage. However, confidence intervals constructed using the new approach combined with Smith's method provide nominal or close to nominal coverage when the intraclass correlation coefficient is small (<0.05), as is the case in most community intervention trials. This study concludes that when a binary outcome variable is measured in a small number of large clusters, confidence intervals for the intraclass correlation coefficient may be constructed by dividing existing clusters into sub-clusters (e.g. groups of 5) and using Smith's method. The resulting confidence intervals provide nominal or close to nominal coverage across a wide range of parameters when the intraclass correlation coefficient is small (<0.05). Application of this method should provide investigators with a better understanding of the uncertainty associated with a point estimator of the intraclass correlation coefficient used for determining the sample size needed for a newly designed community-based trial. © The Author(s) 2015.
Bueno de Souza, Roberta Oliveira; Marcon, Liliane de Faria; Arruda, Alex Sandro Faria de; Pontes Junior, Francisco Luciano; Melo, Ruth Caldeira de
2018-06-01
The present meta-analysis aimed to examine evidence from randomized controlled trials to determine the effects of mat Pilates on measures of physical functional performance in the older population. A search was conducted in the MEDLINE/PubMed, Scopus, Scielo, and PEDro databases between February and March 2017. Only randomized controlled trials that were written in English, included subjects aged 60 yrs who used mat Pilates exercises, included a comparison (control) group, and reported performance-based measures of physical function (balance, flexibility, muscle strength, and cardiorespiratory fitness) were included. The methodological quality of the studies was analyzed according to the PEDro scale and the best-evidence synthesis. The meta-analysis was conducted with the Review Manager 5.3 software. The search retrieved 518 articles, nine of which fulfilled the inclusion criteria. High methodological quality was found in five of these studies. Meta-analysis indicated a large effect of mat Pilates on dynamic balance (standardized mean difference = 1.10, 95% confidence interval = 0.29-1.90), muscle strength (standardized mean difference = 1.13, 95% confidence interval = 0.30-1.96), flexibility (standardized mean difference = 1.22, 95% confidence interval = 0.39-2.04), and cardiorespiratory fitness (standardized mean difference = 1.48, 95% confidence interval = 0.42-2.54) of elderly subjects. There is evidence that mat Pilates improves dynamic balance, lower limb strength, hip and lower back flexibility, and cardiovascular endurance in elderly individuals. Furthermore, high-quality studies are necessary to clarify the effects of mat Pilates on other physical functional measurements among older adults.
Miele, Luca; Cammarota, Giovanni; Vero, Vittoria; Racco, Simona; Cefalo, Consuelo; Marrone, Giuseppe; Pompili, Maurizio; Rapaccini, Gianlodovico; Bianco, Alessandro; Landolfi, Raffaele; Gasbarrini, Antonio; Grieco, Antonio
2012-12-01
Gastro-oesophageal reflux symptoms are usually reported by patients with obesity and metabolic syndrome. Aim of this study was to assess the prevalence and clinical characteristics of gastro-oesophageal reflux symptoms in subjects with non-alcoholic fatty liver disease. Cross-sectional, case-control study of 185 consecutive patients with non-alcoholic fatty liver disease and an age- and sex-matched control group of 112 healthy volunteers. Participants were interviewed with the aid of a previously validated questionnaire to assess lifestyle and reflux symptoms in the 3 months preceding enrolment. Odds ratios were determined before and after adjustment for body mass index, increased waist circumference, physical activity, metabolic syndrome and proton pump inhibitors and/or antiacid medication. The prevalence of heartburn and/or regurgitation and of at least one of gastro-oesophageal reflux symptoms was significantly higher in the non-alcoholic fatty liver disease group. Non-alcoholic fatty liver disease subjects were associated to higher prevalence of heartburn (adjusted odds ratios: 2.17, 95% confidence intervals: 1.16-4.04), regurgitation (adjusted odds ratios: 2.61, 95% confidence intervals: 1.24-5.48) and belching (adjusted odds ratios: 2.01, 95% confidence intervals: 1.12-3.59) and had higher prevalence of at least one GER symptom (adjusted odds ratios: 3.34, 95% confidence intervals: 1.76-6.36). Non-alcoholic fatty liver disease is associated with a higher prevalence of gastro-oesophageal reflux symptoms. Copyright © 2012 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.
Landes, Reid D.; Lensing, Shelly Y.; Kodell, Ralph L.; Hauer-Jensen, Martin
2014-01-01
The dose of a substance that causes death in P% of a population is called an LDP, where LD stands for lethal dose. In radiation research, a common LDP of interest is the radiation dose that kills 50% of the population by a specified time, i.e., lethal dose 50 or LD50. When comparing LD50 between two populations, relative potency is the parameter of interest. In radiation research, this is commonly known as the dose reduction factor (DRF). Unfortunately, statistical inference on dose reduction factor is seldom reported. We illustrate how to calculate confidence intervals for dose reduction factor, which may then be used for statistical inference. Further, most dose reduction factor experiments use hundreds, rather than tens of animals. Through better dosing strategies and the use of a recently available sample size formula, we also show how animal numbers may be reduced while maintaining high statistical power. The illustrations center on realistic examples comparing LD50 values between a radiation countermeasure group and a radiation-only control. We also provide easy-to-use spreadsheets for sample size calculations and confidence interval calculations, as well as SAS® and R code for the latter. PMID:24164553
Cooley, Richard L.
1993-01-01
A new method is developed to efficiently compute exact Scheffé-type confidence intervals for output (or other function of parameters) g(β) derived from a groundwater flow model. The method is general in that parameter uncertainty can be specified by any statistical distribution having a log probability density function (log pdf) that can be expanded in a Taylor series. However, for this study parameter uncertainty is specified by a statistical multivariate beta distribution that incorporates hydrogeologic information in the form of the investigator's best estimates of parameters and a grouping of random variables representing possible parameter values so that each group is defined by maximum and minimum bounds and an ordering according to increasing value. The new method forms the confidence intervals from maximum and minimum limits of g(β) on a contour of a linear combination of (1) the quadratic form for the parameters used by Cooley and Vecchia (1987) and (2) the log pdf for the multivariate beta distribution. Three example problems are used to compare characteristics of the confidence intervals for hydraulic head obtained using different weights for the linear combination. Different weights generally produced similar confidence intervals, whereas the method of Cooley and Vecchia (1987) often produced much larger confidence intervals.
Oono, Ryoko
2017-01-01
High-throughput sequencing technology has helped microbial community ecologists explore ecological and evolutionary patterns at unprecedented scales. The benefits of a large sample size still typically outweigh that of greater sequencing depths per sample for accurate estimations of ecological inferences. However, excluding or not sequencing rare taxa may mislead the answers to the questions 'how and why are communities different?' This study evaluates the confidence intervals of ecological inferences from high-throughput sequencing data of foliar fungal endophytes as case studies through a range of sampling efforts, sequencing depths, and taxonomic resolutions to understand how technical and analytical practices may affect our interpretations. Increasing sampling size reliably decreased confidence intervals across multiple community comparisons. However, the effects of sequencing depths on confidence intervals depended on how rare taxa influenced the dissimilarity estimates among communities and did not significantly decrease confidence intervals for all community comparisons. A comparison of simulated communities under random drift suggests that sequencing depths are important in estimating dissimilarities between microbial communities under neutral selective processes. Confidence interval analyses reveal important biases as well as biological trends in microbial community studies that otherwise may be ignored when communities are only compared for statistically significant differences.
The Applicability of Confidence Intervals of Quantiles for the Generalized Logistic Distribution
NASA Astrophysics Data System (ADS)
Shin, H.; Heo, J.; Kim, T.; Jung, Y.
2007-12-01
The generalized logistic (GL) distribution has been widely used for frequency analysis. However, there is a little study related to the confidence intervals that indicate the prediction accuracy of distribution for the GL distribution. In this paper, the estimation of the confidence intervals of quantiles for the GL distribution is presented based on the method of moments (MOM), maximum likelihood (ML), and probability weighted moments (PWM) and the asymptotic variances of each quantile estimator are derived as functions of the sample sizes, return periods, and parameters. Monte Carlo simulation experiments are also performed to verify the applicability of the derived confidence intervals of quantile. As the results, the relative bias (RBIAS) and relative root mean square error (RRMSE) of the confidence intervals generally increase as return period increases and reverse as sample size increases. And PWM for estimating the confidence intervals performs better than the other methods in terms of RRMSE when the data is almost symmetric while ML shows the smallest RBIAS and RRMSE when the data is more skewed and sample size is moderately large. The GL model was applied to fit the distribution of annual maximum rainfall data. The results show that there are little differences in the estimated quantiles between ML and PWM while distinct differences in MOM.
2017-01-01
High-throughput sequencing technology has helped microbial community ecologists explore ecological and evolutionary patterns at unprecedented scales. The benefits of a large sample size still typically outweigh that of greater sequencing depths per sample for accurate estimations of ecological inferences. However, excluding or not sequencing rare taxa may mislead the answers to the questions ‘how and why are communities different?’ This study evaluates the confidence intervals of ecological inferences from high-throughput sequencing data of foliar fungal endophytes as case studies through a range of sampling efforts, sequencing depths, and taxonomic resolutions to understand how technical and analytical practices may affect our interpretations. Increasing sampling size reliably decreased confidence intervals across multiple community comparisons. However, the effects of sequencing depths on confidence intervals depended on how rare taxa influenced the dissimilarity estimates among communities and did not significantly decrease confidence intervals for all community comparisons. A comparison of simulated communities under random drift suggests that sequencing depths are important in estimating dissimilarities between microbial communities under neutral selective processes. Confidence interval analyses reveal important biases as well as biological trends in microbial community studies that otherwise may be ignored when communities are only compared for statistically significant differences. PMID:29253889
Inconsistent survey reporting in anesthesia journals.
Story, David A; Gin, Veronica; na Ranong, Vanida; Poustie, Stephanie; Jones, Daryl
2011-09-01
As with other types of research, there are concerns about reporting of survey research in anesthesia journals. We hypothesized that use of survey reporting items would be inconsistent in survey research reported in anesthesia journals. After a literature review we constructed a 17-item reporting list for a limited systematic review of survey reporting in 6 anesthesia journals. We identified survey reports by MEDLINE (PubMed) search for January 2000 to April 2009. The initial search identified 347 publications. Of these, we excluded 107 because they were not questionnaire surveys (often audits), were reviews, or were letters. We therefore identified 240 surveys published as full survey reports. From the 17-item reporting list, the median number of items recorded was 9 (interquartile range: 7 to 10; range 2 to 15). The number (and percentage) of surveys reporting specific items ranged widely for different items: from 9 surveys (4%; 95% confidence interval [CI]: 2% to 7%) for sample size to 240 surveys (100%; 95% CI: 98% to 100%) for response rate. In addition to sample size, the 5 least frequently reported items included the following: reporting confidence intervals, 21 surveys (9%; 95% CI: 6% to 13%); stating a hypothesis, 23 of 240 surveys (10%; 95% CI: 7% to 14%); accounting for nonresponders, 61 surveys (25%; 95% CI: 20% to 31%); and survey design, 67 surveys (28%; 95% CI: 33% to 34%). Inconsistent reporting may compromise the transparency and reproducibility of survey reports.
Primary repair of penetrating colon injuries: a systematic review.
Singer, Marc A; Nelson, Richard L
2002-12-01
Primary repair of penetrating colon injuries is an appealing management option; however, uncertainty about its safety persists. This study was conducted to compare the morbidity and mortality of primary repair with fecal diversion in the management of penetrating colon injuries by use of a meta-analysis of randomized, prospective trials. We searched for prospective, randomized trials in MEDLINE (1966 to November 2001), the Cochrane Library, and EMBase using the terms colon, penetrating, injury, colostomy, prospective, and randomized. Studies were included if they were randomized, controlled trials that compared the outcomes of primary repair with fecal diversion in the management of penetrating colon injuries. Five studies were included. Reviewers performed data extraction independently. Outcomes evaluated from each trial included mortality, total complications, infectious complications, intra-abdominal infections, wound complications, penetrating abdominal trauma index, and length of stay. Peto odds ratios for combined effect were calculated with a 95 percent confidence interval for each outcome. Heterogeneity was also assessed for each outcome. The penetrating abdominal trauma index of included subjects did not differ significantly between studies. Mortality was not significantly different between groups (odds ratio, 1.70; 95 percent confidence interval, 0.51-5.66). However, total complications (odds ratio, 0.28; 95 percent confidence interval, 0.18-0.42), total infectious complications (odds ratio, 0.41; 95 percent confidence interval, 0.27-0.63), abdominal infections including dehiscence (odds ratio, 0.59; 95 percent confidence interval, 0.38-0.94), abdominal infections excluding dehiscence (odds ratio, 0.52; 95 percent confidence interval, 0.31-0.86), wound complications including dehiscence (odds ratio, 0.55; 95 percent confidence interval, 0.34-0.89), and wound complications excluding dehiscence (odds ratio, 0.43; 95 percent confidence interval, 0.25-0.76) all significantly favored primary repair. Meta-analysis of currently published randomized, controlled trials favors primary repair over fecal diversion for penetrating colon injuries.
Ford, Rebecca; King, Tania; Priest, Naomi; Kavanagh, Anne
2017-09-01
To provide the first Australian population-based estimates of the association between bullying and adverse mental health outcomes and suicidality among Australian adolescents. Analysis of data from 3537 adolescents, aged 14-15 years from Wave 6 of the K-cohort of Longitudinal Study of Australian Children was conducted. We used Poisson and linear regression to estimate associations between bullying type (none, relational-verbal, physical, both types) and role (no role, victim, bully, victim and bully), and mental health (measured by the Strengths and Difficulties Questionnaire, symptoms of anxiety and depression) and suicidality. Adolescents involved in bullying had significantly increased Strengths and Difficulties Questionnaire, depression and anxiety scores in all bullying roles and types. In terms of self-harm and suicidality, bully-victims had the highest risk of self-harm (prevalence rate ratio 4.7, 95% confidence interval [3.26, 6.83]), suicidal ideation (prevalence rate ratio 4.3, 95% confidence interval [2.83, 6.49]), suicidal plan (prevalence rate ratio 4.1, 95% confidence interval [2.54, 6.58]) and attempts (prevalence rate ratio 2.7, 95% confidence interval [1.39, 5.13]), followed by victims then bullies. The experience of both relational-verbal and physical bullying was associated with the highest risk of self-harm (prevalence rate ratio 4.6, 95% confidence interval [3.15, 6.60]), suicidal ideation or plans (prevalence rate ratio 4.6, 95% confidence interval [3.05, 6.95]; and 4.8, 95% confidence interval [3.01, 7.64], respectively) or suicide attempts (prevalence rate ratio 3.5, 95% confidence interval [1.90, 6.30]). This study presents the first national, population-based estimates of the associations between bullying by peers and mental health outcomes in Australian adolescents. The markedly increased risk of poor mental health outcomes, self-harm and suicidal ideation and behaviours among adolescents who experienced bullying highlights the importance of addressing bullying in school settings.
Steiner, Markus FC; Cezard, Genevieve; Bansal, Narinder; Fischbacher, Colin; Douglas, Anne; Bhopal, Raj; Sheikh, Aziz
2015-01-01
Objective There is evidence of substantial ethnic variations in asthma morbidity and the risk of hospitalisation, but the picture in relation to lower respiratory tract infections is unclear. We carried out an observational study to identify ethnic group differences for lower respiratory tract infections. Design A retrospective, cohort study. Setting Scotland. Participants 4.65 million people on whom information was available from the 2001 census, followed from May 2001 to April 2010. Main outcome measures Hospitalisations and deaths (any time following first hospitalisation) from lower respiratory tract infections, adjusted risk ratios and hazard ratios by ethnicity and sex were calculated. We multiplied ratios and confidence intervals by 100, so the reference Scottish White population’s risk ratio and hazard ratio was 100. Results Among men, adjusted risk ratios for lower respiratory tract infection hospitalisation were lower in Other White British (80, 95% confidence interval 73–86) and Chinese (69, 95% confidence interval 56–84) populations and higher in Pakistani groups (152, 95% confidence interval 136–169). In women, results were mostly similar to those in men (e.g. Chinese 68, 95% confidence interval 56–82), although higher adjusted risk ratios were found among women of the Other South Asians group (145, 95% confidence interval 120–175). Survival (adjusted hazard ratio) following lower respiratory tract infection for Pakistani men (54, 95% confidence interval 39–74) and women (31, 95% confidence interval 18–53) was better than the reference population. Conclusions Substantial differences in the rates of lower respiratory tract infections amongst different ethnic groups in Scotland were found. Pakistani men and women had particularly high rates of lower respiratory tract infection hospitalisation. The reasons behind the high rates of lower respiratory tract infection in the Pakistani community are now required. PMID:26152675
Statistical Significance, Effect Size Reporting, and Confidence Intervals: Best Reporting Strategies
ERIC Educational Resources Information Center
Capraro, Robert M.
2004-01-01
With great interest the author read the May 2002 editorial in the "Journal for Research in Mathematics Education (JRME)" (King, 2002) regarding changes to the 5th edition of the "Publication Manual of the American Psychological Association" (APA, 2001). Of special note to him, and of great import to the field of mathematics education research, are…
Unprotected intercourse in the 2 weeks prior to requesting emergency intrauterine contraception.
Sanders, Jessica N; Howell, Laura; Saltzman, Hanna M; Schwarz, E Bimla; Thompson, Ivana S; Turok, David K
2016-11-01
Previous emergency contraception studies have excluded women who report >1 episode of unprotected or underprotected intercourse. Thus, clinical recommendations are based on exposure to a single episode of underprotected intercourse. We sought to assess the prevalence and timing of underprotected intercourse episodes among women requesting emergency contraception and to examine the probability of pregnancy following an emergency contraception regimen including placement of either a copper intrauterine device or a levonorgestrel intrauterine device with simultaneous administration of an oral levonorgestrel pill in women reporting multiple underprotected intercourse episodes, including episodes beyond the Food and Drug Administration-approved emergency contraception time frame (6-14 days). Women seeking emergency contraception who had a negative pregnancy test and desired either a copper intrauterine device or levonorgestrel emergency contraception regimen enrolled in this prospective observational study. At enrollment, participants reported the number and timing of underprotected intercourse episodes in the previous 14 days. Two weeks later, participants reported the results of a self-administered home pregnancy test. Of the 176 women who presented for emergency contraception and received a same-day intrauterine device, 43% (n = 76) reported multiple underprotected intercourse episodes in the 14 days prior to presenting for emergency contraception. Women with multiple underprotected intercourse episodes reported a median of 3 events (range 2-20). Two-week pregnancy data were available for 172 (98%) participants. Only 1 participant had a positive pregnancy test. Pregnancy occurred in 0 of 97 (0%; 95% confidence interval, 0-3.7%) women with a single underprotected intercourse episode and 1 of 75 (1.3%; 95% confidence interval, 0-7.2%) women reporting multiple underprotected intercourse episodes; this includes 1 of 40 (2.5%; 95% confidence interval, 0-13.2%) women reporting underprotected intercourse 6-14 days prior to intrauterine device insertion. Women seeking emergency contraception from clinics commonly reported multiple recent underprotected intercourse episodes, including episodes occurring beyond the Food and Drug Administration-approved emergency contraception time frame. However, the probability of pregnancy was low following same-day intrauterine device placement. Copyright © 2016 Elsevier Inc. All rights reserved.
Religious hospital policies on reproductive care: what do patients want to know?
Freedman, Lori R; Hebert, Luciana E; Battistelli, Molly F; Stulberg, Debra B
2018-02-01
Religious hospitals are a large and growing part of the American healthcare system. Patients who receive obstetric and other reproductive care in religious hospitals may face religiously-based restrictions on the treatment their doctor can provide. Little is known about patients' knowledge or preferences regarding religiously restricted reproductive healthcare. We aimed to assess women's preferences for knowing a hospital's religion and religiously based restrictions before deciding where to seek care and the acceptability of a hospital denying miscarriage treatment options for religious reasons, with and without informing the patient that other options may be available. We conducted a national survey of women aged 18-45 years. The sample was recruited from AmeriSpeak, a probability-based research panel of civilian noninstitutionalized adults. Of 2857 women invited to participate, 1430 completed surveys online or over the phone, for a survey response rate of 50.1%. All analyses adjusted for the complex sampling design and were weighted to generate estimates representative of the population of US adult reproductive-age women. We used χ 2 tests and multivariable logistic regression to evaluate associations. One third of women aged 18-45 years (34.5%) believe it is somewhat or very important to know a hospital's religion when deciding where to get care, but 80.7% feel it is somewhat or very important to know about a hospital's religious restrictions on care. Being Catholic or attending religious services more frequently does not make one more or less likely to want this information. Compared with Protestant women who do not identify as born-again, women of other religious backgrounds are more likely to consider it important to know a hospital's religious affiliation. These include religious minority women (adjusted odds ratio, 2.17; 95% confidence interval, 1.11-4.27), those who reported no religion/atheist/agnostic (adjusted odds ratio, 2.27; 95% confidence interval, 1.19-4.34), and born-again Protestants (adjusted odds ratio, 2.38; 95% confidence interval, 1.32-4.28). Religious minority women (adjusted odds ratio, 2.36; 95% confidence interval, 1.01-5.51) and those who reported no religion/atheist/agnostic (adjusted odds ratio, 3.16; 95% confidence interval, 1.42-7.04) were more likely to want to know a hospital's restrictions on care. More than two thirds of women find it unacceptable for the hospital to restrict information and treatment options during miscarriage based on religion. Women who attended weekly religious services were significantly more likely to accept such restrictions (adjusted odds ratio, 3.13; 95% confidence interval, 1.70-5.76) and to consider transfer to another site an acceptable solution (adjusted odds ratio, 3.22; 95% confidence interval, 1.69-6.12). The question, "When should a religious hospital be allowed to restrict care based on religion?" was asked, and 52.3% responded never; 16.6%, always; and 31.1%,"under some conditions. The vast majority of adult American women of reproductive age want information about a hospital's religious restrictions on care when deciding where to go for obstetrics/gynecology care. Growth in the US Catholic health care sector suggests an increasing need for transparency about these restrictions so that women can make informed decisions and, when needed, seek alternative providers. Copyright © 2017 Elsevier Inc. All rights reserved.
Relationship between chewing ability and sarcopenia in Japanese community-dwelling older adults.
Murakami, Masaharu; Hirano, Hirohiko; Watanabe, Yutaka; Sakai, Katsuhiko; Kim, Hunkyoung; Katakura, Akira
2015-08-01
It has been reported that if nutrient intake is unbalanced, muscle mass, muscle strength and physical performance declines, and therefore it is important to maintain chewing ability to keep a balanced nutrient intake. However, the relationship between chewing ability and sarcopenia has not been previously reported. Therefore, the present study investigated the relationship between chewing ability and sarcopenia in addition to known sarcopenia-related factors. We examined 761 participants (average age 73.0 ± 5.1 years), who lived in the Itabashi city of Tokyo. Our research was designed to examine the relationship between chewing ability and sarcopenia. We carried out regression analysis to analyze the relationship with sarcopenia-related factors with consideration of the age of the participants. The 761 participants were divided into two groups in terms of the stage of sarcopenia according to whether there was a deterioration of muscle strength or physical performance. Furthermore, we carried out logistic regression analyses on the value as a dependent variable, including known sarcopenia-related factors. There were significant correlations of sarcopenia with age (odds ratio 2.37, 95% confidence interval 1.52-3.70), body mass index (odds ratio 0.75, 95% confidence interval 0.69-0.81) and chewing ability (odds ratio 2.18, 95% confidence interval 1.21-3.93). The present study shows that chewing ability is related to sarcopenia, which is equal to the relationship with the known factor of age by odds ratio. © 2014 Japan Geriatrics Society.
Elming, H; Holm, E; Jun, L; Torp-Pedersen, C; Køber, L; Kircshoff, M; Malik, M; Camm, J
1998-09-01
To evaluate the prognostic value of the QT interval and QT interval dispersion in total and in cardiovascular mortality, as well as in cardiac morbidity, in a general population. The QT interval was measured in all leads from a standard 12-lead ECG in a random sample of 1658 women and 1797 men aged 30-60 years. QT interval dispersion was calculated from the maximal difference between QT intervals in any two leads. All cause mortality over 13 years, and cardiovascular mortality as well as cardiac morbidity over 11 years, were the main outcome parameters. Subjects with a prolonged QT interval (430 ms or more) or prolonged QT interval dispersion (80 ms or more) were at higher risk of cardiovascular death and cardiac morbidity than subjects whose QT interval was less than 360 ms, or whose QT interval dispersion was less than 30 ms. Cardiovascular death relative risk ratios, adjusted for age, gender, myocardial infarct, angina pectoris, diabetes mellitus, arterial hypertension, smoking habits, serum cholesterol level, and heart rate were 2.9 for the QT interval (95% confidence interval 1.1-7.8) and 4.4 for QT interval dispersion (95% confidence interval 1.0-19-1). Fatal and non-fatal cardiac morbidity relative risk ratios were similar, at 2.7 (95% confidence interval 1.4-5.5) for the QT interval and 2.2 (95% confidence interval 1.1-4.0) for QT interval dispersion. Prolongation of the QT interval and QT interval dispersion independently affected the prognosis of cardiovascular mortality and cardiac fatal and non-fatal morbidity in a general population over 11 years.
Randomized trials published in some Chinese journals: how many are randomized?
Wu, Taixiang; Li, Youping; Bian, Zhaoxiang; Liu, Guanjian; Moher, David
2009-07-02
The approximately 1100 medical journals now active in China are publishing a rapidly increasing number of research reports, including many studies identified by their authors as randomized controlled trials. It has been noticed that these reports mostly present positive results, and their quality and authenticity have consequently been called into question. We investigated the adequacy of randomization of clinical trials published in recent years in China to determine how many of them met acceptable standards for allocating participants to treatment groups. The China National Knowledge Infrastructure electronic database was searched for reports of randomized controlled trials on 20 common diseases published from January 1994 to June 2005. From this sample, a subset of trials that appeared to have used randomization methods was selected. Twenty-one investigators trained in the relevant knowledge, communication skills and quality control issues interviewed the original authors of these trials about the participant randomization methods and related quality-control features of their trials. From an initial sample of 37,313 articles identified in the China National Knowledge Infrastructure database, we found 3137 apparent randomized controlled trials. Of these, 1452 were studies of conventional medicine (published in 411 journals) and 1685 were studies of traditional Chinese medicine (published in 352 journals). Interviews with the authors of 2235 of these reports revealed that only 207 studies adhered to accepted methodology for randomization and could on those grounds be deemed authentic randomized controlled trials (6.8%, 95% confidence interval 5.9-7.7). There was no statistically significant difference in the rate of authenticity between randomized controlled trials of traditional interventions and those of conventional interventions. Randomized controlled trials conducted at hospitals affiliated to medical universities were more likely to be authentic than trials conducted at level 3 and level 2 hospitals (relative risk 1.58, 95% confidence interval 1.18-2.13, and relative risk 14.42, 95% confidence interval 9.40-22.10, respectively). The likelihood of authenticity was higher in level 3 hospitals than in level 2 hospitals (relative risk 9.32, 95% confidence interval 5.83-14.89). All randomized controlled trials of pre-market drug clinical trial were authentic by our criteria. Of the trials conducted at university-affiliated hospitals, 56.3% were authentic (95% confidence interval 32.0-81.0). Most reports of randomized controlled trials published in some Chinese journals lacked an adequate description of randomization. Similarly, most so called 'randomized controlled trials' were not real randomized controlled trials owing to a lack of adequate understanding on the part of the authors of rigorous clinical trial design. All randomized controlled trials of pre-market drug clinical trial included in this research were authentic. Randomized controlled trials conducted by authors in high level hospitals, especially in hospitals affiliated to medical universities had a higher rate of authenticity. That so many non-randomized controlled trials were published as randomized controlled trials reflected the fact that peer review needs to be improved and a good practice guide for peer review including how to identify the authenticity of the study urgently needs to be developed.
Randomized trials published in some Chinese journals: how many are randomized?
Wu, Taixiang; Li, Youping; Bian, Zhaoxiang; Liu, Guanjian; Moher, David
2009-01-01
Background The approximately 1100 medical journals now active in China are publishing a rapidly increasing number of research reports, including many studies identified by their authors as randomized controlled trials. It has been noticed that these reports mostly present positive results, and their quality and authenticity have consequently been called into question. We investigated the adequacy of randomization of clinical trials published in recent years in China to determine how many of them met acceptable standards for allocating participants to treatment groups. Methods The China National Knowledge Infrastructure electronic database was searched for reports of randomized controlled trials on 20 common diseases published from January 1994 to June 2005. From this sample, a subset of trials that appeared to have used randomization methods was selected. Twenty-one investigators trained in the relevant knowledge, communication skills and quality control issues interviewed the original authors of these trials about the participant randomization methods and related quality-control features of their trials. Results From an initial sample of 37,313 articles identified in the China National Knowledge Infrastructure database, we found 3137 apparent randomized controlled trials. Of these, 1452 were studies of conventional medicine (published in 411 journals) and 1685 were studies of traditional Chinese medicine (published in 352 journals). Interviews with the authors of 2235 of these reports revealed that only 207 studies adhered to accepted methodology for randomization and could on those grounds be deemed authentic randomized controlled trials (6.8%, 95% confidence interval 5.9–7.7). There was no statistically significant difference in the rate of authenticity between randomized controlled trials of traditional interventions and those of conventional interventions. Randomized controlled trials conducted at hospitals affiliated to medical universities were more likely to be authentic than trials conducted at level 3 and level 2 hospitals (relative risk 1.58, 95% confidence interval 1.18–2.13, and relative risk 14.42, 95% confidence interval 9.40–22.10, respectively). The likelihood of authenticity was higher in level 3 hospitals than in level 2 hospitals (relative risk 9.32, 95% confidence interval 5.83–14.89). All randomized controlled trials of pre-market drug clinical trial were authentic by our criteria. Of the trials conducted at university-affiliated hospitals, 56.3% were authentic (95% confidence interval 32.0–81.0). Conclusion Most reports of randomized controlled trials published in some Chinese journals lacked an adequate description of randomization. Similarly, most so called 'randomized controlled trials' were not real randomized controlled trials owing toa lack of adequate understanding on the part of the authors of rigorous clinical trial design. All randomized controlled trials of pre-market drug clinical trial included in this research were authentic. Randomized controlled trials conducted by authors in high level hospitals, especially in hospitals affiliated to medical universities had a higher rate of authenticity. That so many non-randomized controlled trials were published as randomized controlled trials reflected the fact that peer review needs to be improved and a good practice guide for peer review including how to identify the authenticity of the study urgently needs to be developed. PMID:19573242
Arsenault, Lisa N; Xu, Kathleen; Taveras, Elsie M; Hacker, Karen A
2014-01-01
Successful childhood obesity interventions frequently focus on behavioral modification and involve parents or family members. Parental confidence in supporting behavior change may be an element of successful family-based prevention efforts. We aimed to determine whether parents' own obesity-related behaviors were related to their confidence in supporting their child's achievement of obesity-related behavioral goals. Cross-sectional analyses of data collected at baseline of a randomized control trial testing a treatment intervention for obese children (n = 787) in primary care settings (n = 14). Five obesity-related behaviors (physical activity, screen time, sugar-sweetened beverage, sleep duration, fast food) were self-reported by parents for themselves and their child. Behaviors were dichotomized on the basis of achievement of behavioral goals. Five confidence questions asked how confident the parent was in helping their child achieve each goal. Logistic regression modeling high confidence was conducted with goal achievement and demographics as independent variables. Parents achieving physical activity or sleep duration goals were significantly more likely to be highly confident in supporting their child's achievement of those goals (physical activity, odds ratio 1.76; 95% confidence interval 1.19-2.60; sleep, odds ratio 1.74; 95% confidence interval 1.09-2.79) independent of sociodemographic variables and child's current behavior. Parental achievements of TV watching and fast food goals were also associated with confidence, but significance was attenuated after child's behavior was included in models. Parents' own obesity-related behaviors are factors that may affect their confidence to support their child's behavior change. Providers seeking to prevent childhood obesity should address parent/family behaviors as part of their obesity prevention strategies. Copyright © 2014 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.
Bernstein, Kyle T; Liu, Kai-Lih; Begier, Elizabeth M; Koblin, Beryl; Karpati, Adam; Murrill, Christopher
2008-07-14
While the Centers for Disease Control and Prevention recommends at least annual human immunodeficiency virus (HIV) screening for men who have sex with men (MSM), a large number of HIV infections among this population go unrecognized. We examined the association between disclosing to their medical providers (eg, physicians, nurses, physician assistants) same-sex attraction and self-reported HIV testing among MSM in New York City, New York. All men recruited from the New York City National HIV Behavioral Surveillance (NHBS) project who reported at least 1 male sex partner in the past year and self-reported as HIV seronegative were included in the analysis. The primary outcome of interest was a participant having told his health care provider that he is attracted to or has sex with other men. Sociodemographic and behavioral factors were examined in relation to disclosure of same-sex attraction. Among the 452 MSM respondents, 175 (39%) did not disclose to their health care providers. Black and Hispanic MSM (adjusted odds ratios, 0.28 [95% confidence interval, 0.14-0.53] and 0.46 [95% confidence interval, 0.24-0.85], respectively) were less likely than white MSM to have disclosed to their health care providers. No MSM who identified themselves as bisexual had disclosed to their health care providers. Those who had ever been tested for HIV were more likely to have disclosed to their health care providers (adjusted odds ratio, 2.10; 95% confidence interval, 1.01-4.38). These data suggest that risk-based HIV testing, which is contingent on health care providers being aware of their patients' risks, could miss these high-risk persons.
The development of the ICF vestibular environmental scale.
Whitney, Susan L; Alghadir, Ahmad; Alghwiri, Alia; Alshebber, Kefah M; Alshehri, Mohammed; Furman, Joseph M; Mueller, Martin; Grill, Eva
2016-07-02
People with vestibular disorders report changes in symptoms based on their environment with many situations increasing their symptoms. The purpose of this paper was to utilize the International Classification of Functioning Disability and Health (ICF) from the World Health Organization (WHO) to describe common environmental triggers for dizziness in persons living with balance and vestibular disorders. A multi-centre cross-sectional study was conducted with four different centres on three different continents, including patients from the United States (Pittsburgh), Germany (Munich), Jordan (Amman) and Saudi Arabia (Riyadh). Three hundred eighty one persons with vestibular disorders participated. A 9-item questionnaire (the Vestibular Environmental Scale) was developed from existing ICF items, which were compared to Dizziness Handicap Inventory (DHI) scores. Sixty-five percent of participants reported that "quick movements in the vicinity" increased symptoms, "crowds" at 45%, and "design of buildings, e.g. narrow hallways, stairs, elevators" at 42%. The "crowds" item was a good positive predictor of psychogenic vertigo (OR 1.8, 95% Confidence Interval 1.03-3.16), while "food" (OR 0.47, 95% Confidence Interval 0.17-1.29) and "light" (OR 0.41 95% Confidence Interval 0.23-0.75) were negative predictors of psychogenic vertigo. There also was a positive correlation between the number of triggers and DHI score (Spearman correlation coefficient 0.47, p < 0.0001). Sixty-eight percent of the subjects reported an increase in symptoms with between 1 and 4 environmental triggers. In our cross cultural sample, environmental triggers affect dizziness in persons living with balance and vestibular disorders. The use of items from the ICF of the WHO may help to promote cross cultural sharing of information in persons with dizziness.
The impact of prenatal parental tobacco smoking on risk of diabetes mellitus in middle-aged women.
La Merrill, M A; Cirillo, P M; Krigbaum, N Y; Cohn, B A
2015-06-01
Growing evidence indicates that parental smoking is associated with risk of offspring obesity. The purpose of this study was to identify whether parental tobacco smoking during gestation was associated with risk of diabetes mellitus. This is a prospective study of 44- to 54-year-old daughters (n = 1801) born in the Child Health and Development Studies pregnancy cohort between 1959 and 1967. Their mothers resided near Oakland California, were members of the Kaiser Foundation Health Plan and reported parental tobacco smoking during an early pregnancy interview. Daughters reported physician diagnoses of diabetes mellitus and provided blood samples for hemoglobin A1C measurement. Prenatal maternal smoking had a stronger association with daughters' diabetes mellitus risk than prenatal paternal smoking, and the former persisted after adjustment for parental race, diabetes and employment (aRR = 2.4 [95% confidence intervals 1.4-4.1] P < 0.01 and aRR = 1.7 [95% confidence intervals 1.0-3.0] P = 0.05, respectively). Estimates of the effect of parental smoking were unchanged when further adjusted by daughters' birth weight or current body mass index (BMI). Maternal smoking was also significantly associated with self-reported type 2 diabetes diagnosis (2.3 [95% confidence intervals 1.0-5.0] P < 0.05). Having parents who smoked during pregnancy was associated with an increased risk of diabetes mellitus among adult daughters, independent of known risk factors, providing further evidence that prenatal environmental chemical exposures independent of birth weight and current BMI may contribute to adult diabetes mellitus. While other studies seek to confirm our results, caution toward tobacco smoking by or proximal to pregnant women is warranted in diabetes mellitus prevention efforts.
Triggering of acute coronary occlusion by episodes of anger.
Buckley, Thomas; Hoo, Soon Y Soo; Fethney, Judith; Shaw, Elizabeth; Hanson, Peter S; Tofler, Geoffrey H
2015-12-01
The aim of this study was to report the association between episodes of anger and acute myocardial infarction (MI) in patients with angiographically confirmed coronary occlusion. 313 participants with acute coronary occlusion (Thrombolysis In Myocardial Infarction 0 or 1 at emergency angiography) reported frequency of anger episodes in the 48 h prior to MI. In primary analysis, anger exposures within 2 h and 2-4 h prior to symptom onset were compared with subjects' own usual yearly exposure to anger using case-crossover methodology. Anger level ≥5 (on an anger scale of 1-7) was reported by seven (2.2%) participants within 2 h of MI. Compared with usual frequency, the relative risk of onset of MI symptoms occurring within 2 h of anger level ≥5 (defined as very angry) was 8.5 (95% confidence interval 4.1-17.6). Anger level <5 was not associated with onset of MI symptoms. Compared with 24-26 h pre MI, anxiety scores >75th percentile on State-Trait Personality Inventory were associated with a relative risk of 2.0 (95% confidence interval 1.1-3.8) and in those above the 90th percentile, the relative risk of MI symptom onset was 9.5 (95% confidence interval 2.2-40.8). Findings confirm that episodes of intense anger, defined as being 'very angry, body tense, clenching fists or teeth' (within 2 h) are associated with increased relative risk for acute coronary occlusion. Additionally, increased anxiety was associated with coronary occlusion. Further study, including the role of potential modifiers, may provide insight into prevention of MI during acute emotional episodes. © The European Society of Cardiology 2015.
den Herder-van der Eerden, Marlieke; Ebenau, Anne; Payne, Sheila; Preston, Nancy; Radbruch, Lukas; Linge-Dahl, Lisa; Csikos, Agnes; Busa, Csilla; Van Beek, Karen; Groot, Marieke; Vissers, Kris; Hasselaar, Jeroen
2018-06-01
Although examining perspectives of patients on integrated palliative care organisation is essential, available literature is largely based on administrative data or healthcare professionals' perspectives. (1) Providing insight into the composition and quality of care networks of patients receiving palliative care and (2) describing perceived integration between healthcare professionals within these networks and its association with overall satisfaction. Cross-sectional explorative design. We recruited 157 patients (62% cancer, 25% chronic obstructive pulmonary disease, 13% chronic heart failure, mean age 68 years, 55% female) from 23 integrated palliative care initiatives in Belgium, Germany, the United Kingdom, Hungary and the Netherlands. About 33% reported contact with a palliative care specialist and 48% with a palliative care nurse. Relationships with palliative care specialists were rated significantly higher than other physicians ( p < 0.001). Compared to patients with cancer, patients with chronic obstructive pulmonary disease (odds ratio = 0.16, confidence interval (0.04; 0.57)) and chronic heart failure (odds ratio = 0.11, confidence interval (0.01; 0.93)) had significantly lower odds of reporting contact with palliative care specialists and patients with chronic obstructive pulmonary disease (odds ratio = 0.23, confidence interval (0.08; 0.71)) had significantly lower odds of reporting contact with palliative care nurses. Perceptions of main responsible healthcare professionals or caregivers in patient's care networks varied across countries. Perceived integration was significantly associated with overall satisfaction. Palliative care professionals are not always present or recognised as such in patients' care networks. Expert palliative care involvement needs to be explicated especially for non-cancer patients. One healthcare professional should support patients in understanding and navigating their palliative care network. Patients seem satisfied with care provision as long as continuity of care is provided.
Stokes, Andrew; Collins, Jason M; Berry, Kaitlyn M; Reynolds, Lindsay M; Fetterman, Jessica L; Rodriguez, Carlos J; Siegel, Michael B; Benjamin, Emelia J
2018-04-26
Characterizing electronic cigarette (e-cigarette) use patterns is important for guiding tobacco regulatory policy and projecting the future burden of tobacco-related diseases. Few studies have examined patterns of e-cigarette use in individuals with cardiovascular disease (CVD). We examined e-cigarette use in adults aged 18 to 89 years with a history of CVD, using data from the 2014 National Health Interview Survey. We investigated associations between ever and current e-cigarette use and smoking with multivariable logistic regression. In a secondary analysis, we modeled the association between e-cigarette use and a quit attempt over the past year. Former smokers with CVD who quit smoking within the past year showed 1.85 (95% confidence interval, 1.03, 3.33) times the odds of having ever used e-cigarettes as compared with those who reported being "some days" current smokers. Current smokers who attempted to quit smoking within the past year showed significantly increased odds of ever having used e-cigarettes (odds ratio, 1.70; 95% confidence interval, 1.25, 2.30) and currently using e-cigarettes (odds ratio, 1.97; 95% confidence interval, 1.32, 2.95) as compared with smokers who had not attempted to quit over the past year. Individuals with CVD who recently quit smoking or reported a recent quit attempt were significantly more likely to use e-cigarettes than current smokers and those who did not report a quit attempt. Our findings may indicate that this population is using e-cigarettes as an aid to smoking cessation. Characterizing emerging e-cigarette use behaviors in adults with CVD may help to inform outreach activities aimed at this high-risk population. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.
Longitudinal risk factors for persistent fatigue in adolescents.
Viner, Russell M; Clark, Charlotte; Taylor, Stephanie J C; Bhui, Kam; Klineberg, Emily; Head, Jenny; Booy, Robert; Stansfeld, Stephen A
2008-05-01
To examine whether sedentary behavior, obesity, smoking, and depression are risk factors for persistent fatigue in adolescents. Longitudinal population-based survey. Twenty-eight randomly selected schools in east London, England, in 2001 and 2003. A total of 1880 adolescents (49% male; 81% nonwhite British) aged 11 to 12 years and 13 to 14 years in 2000. Confidential questionnaires completed in class. Persistent fatigue (extreme tiredness twice weekly or more often in the previous month at both surveys), sedentary behavior, physical activity, depressive symptoms, body mass index, and smoking. Severe fatigue was reported in 11% of participants aged 11 to 14 years and 17% of participants aged 13 to 16 years. Eighty-four participants (4%) reported persistent fatigue. Across both surveys, only 3 pupils reported chronic fatigue syndrome. In multivariate logistic regression, risk of persistent fatigue was independently associated with being sedentary for more than 4 hours per day (odds ratio = 1.6; 95% confidence interval, 1.1-2.3; P = .01), being physically active (odds ratio = 1.5; 95% confidence interval, 1.1-2.3; P = .004), and depressive symptoms (odds ratio = 2.0; 95% confidence interval, 1.5-2.7; P < .001) in the first survey, after adjustment for age, sex, and socioeconomic status. Obesity and smoking were not associated with fatigue. Persistent fatigue is common. Being highly sedentary or highly active independently increased the risk of persistent fatigue, suggesting that divergence in either direction from healthy levels of activity increases the risk for persistent fatigue. Mental health is important in the etiology of persistent fatigue. To help define effective preventive strategies, further work is needed on the mechanisms by which these factors contribute to fatigue.
Richter, Randy R; Sebelski, Chris A; Austin, Tricia M
2016-09-01
The quality of abstract reporting in physical therapy literature is unknown. The purpose of this study was to provide baseline data for judging the future impact of the 2010 Consolidated Standards of Reporting Trials statement specifically referencing the 2008 Consolidated Standards of Reporting Trials statement for reporting of abstracts of randomized controlled trials across and between a broad sample and a core sample of physical therapy literature. A cross-sectional, bibliographic analysis was conducted. Abstracts of randomized controlled trials from 2009 were retrieved from PubMed, PEDro, and CENTRAL. Eligibility was determined using PEDro criteria. For outcomes measures, items from the Consolidated Standards of Reporting Trials statement for abstract reporting were used for assessment. Raters were not blinded to citation details. Using a computer-generated set of random numbers, 150 abstracts from 112 journals comprised the broad sample. A total of 53 abstracts comprised the core sample. Fourteen of 20 Consolidated Standards of Reporting Trials items for both samples were reported in less than 50% of the abstracts. Significantly more abstracts in the core sample reported (% difference core - broad; 95% confidence interval) title (28.4%; 12.9%-41.2%), blinding (15.2%; 1.6%-29.8%), setting (47.6%; 32.4%-59.4%), and confidence intervals (13.1%; 5.0%-25.1%). These findings provide baseline data for determining if continuing efforts to improve abstract reporting are heeded.
Use of aromatherapy products and increased risk of hand dermatitis in massage therapists.
Crawford, Glen H; Katz, Kenneth A; Ellis, Elliot; James, William D
2004-08-01
To determine the 12-month prevalence of hand dermatitis among massage therapists, to investigate a potential association between hand dermatitis and the use of aromatherapy products, and to study potential associations with other known risk factors for hand dermatitis. Mailed survey. Philadelphia, Pa. Members of a national massage therapy organization who live in the greater Philadelphia region. Self-reported and symptom-based prevalences of hand dermatitis. The number of respondents was 350 (57%). The 12-month prevalence of hand dermatitis in subjects was 15% by self-reported criteria and 23% by a symptom-based method. In multivariate analysis, statistically significant independent risk factors for self-reported hand dermatitis included use of aromatherapy products in massage oils, lotions, or creams (odds ratio, 3.27; 95% confidence interval, 1.53-7.02; P =.002) and history of atopic dermatitis (odds ratio, 8.06; 95% confidence interval, 3.39-19.17; P<.001). The prevalence of hand dermatitis in massage therapists is high. Significant independent risk factors include use of aromatherapy products in massage oils, creams, or lotions and history of atopic dermatitis.
Intakes of magnesium, potassium, and calcium and the risk of stroke among men.
Adebamowo, Sally N; Spiegelman, Donna; Flint, Alan J; Willett, Walter C; Rexrode, Kathryn M
2015-10-01
Intakes of magnesium, potassium, and calcium have been inversely associated with the incidence of hypertension, a known risk factor for stroke. However, only a few studies have examined intakes of these cations in relation to risk of stroke. The aim of this study was to investigate whether high intake of magnesium, potassium, and calcium is associated with reduced stroke risk among men. We prospectively examined the associations between intakes of magnesium, potassium, and calcium from diet and supplements, and the risk of incident stroke among 42 669 men in the Health Professionals Follow-up Study, aged 40 to 75 years and free of diagnosed cardiovascular disease and cancer at baseline in 1986. We calculated the hazard ratio of total, ischemic, and haemorrhagic strokes by quintiles of each cation intake, and of a combined dietary score of all three cations, using multivariate Cox proportional hazard models. During 24 years of follow-up, 1547 total stroke events were documented. In multivariate analyses, the relative risks and 95% confidence intervals of total stroke for men in the highest vs. lowest quintile were 0·87 (95% confidence interval, 0·74-1·02; P, trend = 0·04) for dietary magnesium, 0·89 (95% confidence interval, 0·76-1·05; P, trend = 0·10) for dietary potassium, and 0·89 (95% confidence interval, 0·75-1·04; P, trend = 0·25) for dietary calcium intake. The relative risk of total stroke for men in the highest vs. lowest quintile was 0·74 (95% confidence interval, 0·59-0·93; P, trend = 0·003) for supplemental magnesium, 0·66 (95% confidence interval, 0·50-0·86; P, trend = 0·002) for supplemental potassium, and 1·01 (95% confidence interval, 0·84-1·20; P, trend = 0·83) for supplemental calcium intake. For total intake (dietary and supplemental), the relative risk of total stroke for men in the highest vs. lowest quintile was 0·83 (95% confidence interval, 0·70-0·99; P, trend = 0·04) for magnesium, 0·88 (95% confidence interval, 0·75-4; P, trend = 6) for potassium, and 3 (95% confidence interval, 79-09; P, trend = 84) for calcium. Men in the highest quintile for a combined dietary score of all three cations had a multivariate relative risk of 0·79 (95% confidence interval, 0·67-0·92; P, trend = 0·008) for total stroke, compared with those in the lowest. A diet rich in magnesium, potassium, and calcium may contribute to reduced risk of stroke among men. Because of significant collinearity, the independent contribution of each cation is difficult to define. © 2015 World Stroke Organization.
Schroeder, Emily B; Chonchol, Michel; Shetterly, Susan M; Powers, J David; Adams, John L; Schmittdiel, Julie A; Nichols, Gregory A; O'Connor, Patrick J; Steiner, John F
2018-05-07
In individuals with diabetes, the comparative effectiveness of add-on antihypertensive medications added to an angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker on the risk of significant kidney events is unknown. We used an observational, multicenter cohort of 21,897 individuals with diabetes to compare individuals who added β -blockers, dihydropyridine calcium channel blockers, loop diuretics, or thiazide diuretics to angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers. We examined the hazard of significant kidney events, cardiovascular events, and death using Cox proportional hazard models with propensity score weighting. The composite significant kidney event end point was defined as the first occurrence of a ≥30% decline in eGFR to an eGFR<60 ml/min per 1.73 m 2 , initiation of dialysis, or kidney transplant. The composite cardiovascular event end point was defined as the first occurrence of hospitalization for acute myocardial infarction, acute coronary syndrome, stroke, or congestive heart failure; coronary artery bypass grafting; or percutaneous coronary intervention, and it was only examined in those free of cardiovascular disease at baseline. Over a maximum of 5 years, there were 4707 significant kidney events, 1498 deaths, and 818 cardiovascular events. Compared with thiazide diuretics, hazard ratios for significant kidney events for β -blockers, calcium channel blockers, and loop diuretics were 0.81 (95% confidence interval, 0.74 to 0.89), 0.67 (95% confidence interval, 0.58 to 0.78), and 1.19 (95% confidence interval, 1.00 to 1.41), respectively. Compared with thiazide diuretics, hazard ratios of mortality for β -blockers, calcium channel blockers, and loop diuretics were 1.19 (95% confidence interval, 0.97 to 1.44), 0.73 (95% confidence interval, 0.52 to 1.03), and 1.67 (95% confidence interval, 1.31 to 2.13), respectively. Compared with thiazide diuretics, hazard ratios of cardiovascular events for β -blockers, calcium channel blockers, and loop diuretics compared with thiazide diuretics were 1.65 (95% confidence interval, 1.39 to 1.96), 1.05 (95% confidence interval, 0.80 to 1.39), and 1.55 (95% confidence interval, 1.05 to 2.27), respectively. Compared with thiazide diuretics, calcium channel blockers were associated with a lower risk of significant kidney events and a similar risk of cardiovascular events. Copyright © 2018 by the American Society of Nephrology.
Du, Yongming; Ye, Man; Zheng, Feiyun
2014-07-01
To determine the specific effect of controlled cord traction in the third stage of labor in the prevention of postpartum hemorrhage. We searched PubMed, Scopus and Web of Science (inception to 30 October 2013). Randomized controlled trials comparing controlled cord traction with hands-off management in the third stage of labor were included. Five randomized controlled trials involving a total of 30 532 participants were eligible. No significant difference was found between controlled cord traction and hands-off management groups with respect to the incidence of severe postpartum hemorrhage (relative risk 0.91, 95% confidence interval 0.77-1.08), need for blood transfusion (relative risk 0.96, 95% confidence interval 0.69-1.33) or therapeutic uterotonics (relative risk 0.94, 95% confidence interval 0.88-1.01). However, controlled cord traction reduced the incidence of postpartum hemorrhage in general (relative risk 0.93, 95% confidence interval 0.87-0.99; number-needed-to-treat 111, 95% confidence interval 61-666), as well manual removal of the placenta (relative risk 0.70, 95% confidence interval 0.58-0.84) and duration of the third stage of labor (mean difference -3.20, 95% confidence interval -3.21 to -3.19). Controlled cord traction appears to reduce the risk of any postpartum hemorrhage in a general sense, as well as manual removal of the placenta and the duration of the third stage of labor. However, the reduction in the occurrence of severe postpartum hemorrhage, need for additional uterotonics and blood transfusion is not statistically significant. © 2014 Nordic Federation of Societies of Obstetrics and Gynecology.
Roland, Christina L; Starker, Lee F; Kang, Y; Chatterjee, Deyali; Estrella, Jeannelyn; Rashid, Asif; Katz, Matthew H; Aloia, Thomas A; Lee, Jeffrey E; Dasari, Arvind; Yao, James C; Fleming, Jason B
2017-03-01
Gastrointestinal neuroendocrine tumors have frequent loss of DPC4/SMAD4 expression, a known tumor suppressor. The impact of SMAD4 loss on gastrointestinal neuroendocrine tumors aggressiveness or cancer-related patient outcomes is not defined. We examined the expression of SMAD4 in resected gastrointestinal neuroendocrine tumors and its impact on oncologic outcomes. Patients who underwent complete curative operative resection of gastrointestinal neuroendocrine tumors were identified retrospectively (n = 38). Immunohistochemical staining for SMAD4 expression was scored by a blinded pathologist and correlated with clinicopathologic features and oncologic outcomes. Twenty-nine percent of the gastrointestinal neuroendocrine tumors were SMAD4-negative and 71% SMAD4-positive. Median overall survival was 155 months (95% confidence interval, 102-208 months). Loss of SMAD4 was associated with both decreased median disease-free survival (28 months; 95% confidence interval, 16-40) months compared with 223 months (95% confidence interval, 3-443 months) for SMAD4-positive patients (P = .03) and decreased median disease-specific survival (SMAD4: 137 [95% confidence interval, 81-194] months versus SMAD4-positive: 204 [95% confidence interval, 143-264] months; P = .04). This translated into a decrease in median overall survival (SMAD4-negative: 125 (95% confidence interval, 51-214) months versus SMAD4-positive: 185 (95% confidence interval, 138-232) months; P = .02). Consistent with the known biology of the DPC4/SMAD4 gene, an absence of its protein expression in primary gastrointestinal neuroendocrine tumors was negatively associated with outcomes after curative operative resection. Copyright © 2016 Elsevier Inc. All rights reserved.
Bansal, Ravi; Staib, Lawrence H.; Laine, Andrew F.; Xu, Dongrong; Liu, Jun; Posecion, Lainie F.; Peterson, Bradley S.
2010-01-01
Images from different individuals typically cannot be registered precisely because anatomical features within the images differ across the people imaged and because the current methods for image registration have inherent technological limitations that interfere with perfect registration. Quantifying the inevitable error in image registration is therefore of crucial importance in assessing the effects that image misregistration may have on subsequent analyses in an imaging study. We have developed a mathematical framework for quantifying errors in registration by computing the confidence intervals of the estimated parameters (3 translations, 3 rotations, and 1 global scale) for the similarity transformation. The presence of noise in images and the variability in anatomy across individuals ensures that estimated registration parameters are always random variables. We assume a functional relation among intensities across voxels in the images, and we use the theory of nonlinear, least-squares estimation to show that the parameters are multivariate Gaussian distributed. We then use the covariance matrix of this distribution to compute the confidence intervals of the transformation parameters. These confidence intervals provide a quantitative assessment of the registration error across the images. Because transformation parameters are nonlinearly related to the coordinates of landmark points in the brain, we subsequently show that the coordinates of those landmark points are also multivariate Gaussian distributed. Using these distributions, we then compute the confidence intervals of the coordinates for landmark points in the image. Each of these confidence intervals in turn provides a quantitative assessment of the registration error at a particular landmark point. Because our method is computationally intensive, however, its current implementation is limited to assessing the error of the parameters in the similarity transformation across images. We assessed the performance of our method in computing the error in estimated similarity parameters by applying that method to real world dataset. Our results showed that the size of the confidence intervals computed using our method decreased – i.e. our confidence in the registration of images from different individuals increased – for increasing amounts of blur in the images. Moreover, the size of the confidence intervals increased for increasing amounts of noise, misregistration, and differing anatomy. Thus, our method precisely quantified confidence in the registration of images that contain varying amounts of misregistration and varying anatomy across individuals. PMID:19138877
Juskewitch, Justin E; Prasad, Swati; Salas, Carlos F Santillan; Huskins, W Charles
2012-01-01
To assess interobserver reliability of the identification of episodes of the systemic inflammatory response syndrome in critically ill hospitalized infants and children. Retrospective, cross-sectional study of the application of the 2005 consensus definition of systemic inflammatory response syndrome in infants and children by two independent, trained reviewers using information in the electronic medical record. Eighteen-bed pediatric multidisciplinary medical/surgical pediatric intensive care unit. A randomly selected sample of children admitted consecutively to the pediatric intensive care unit between May 1 and September 30, 2009. None. Sixty infants and children were selected from a total of 343 admitted patients. Their median age was 3.9 yrs (interquartile range, 1.5-12.7), 57% were female, and 68% were Caucasian. Nineteen (32%) children were identified by both reviewers as having an episode of systemic inflammatory response syndrome (88% agreement, 95% confidence interval 78-94; κ = 0.75, 95% confidence interval 0.59-0.92). Among these 19 children, agreement between the reviewers for individual systemic inflammatory response syndrome criteria was: temperature (84%, 95% confidence interval 60-97); white blood cell count (89%, 95% confidence interval 67-99); respiratory rate (84%, 95% confidence interval 60-97); and heart rate (68%, 95% confidence interval 33-87). Episodes of systemic inflammatory response syndrome in critically ill infants and children can be identified reproducibly using the consensus definition.
NASA Technical Reports Server (NTRS)
Rutledge, Charles K.
1988-01-01
The validity of applying chi-square based confidence intervals to far-field acoustic flyover spectral estimates was investigated. Simulated data, using a Kendall series and experimental acoustic data from the NASA/McDonnell Douglas 500E acoustics test, were analyzed. Statistical significance tests to determine the equality of distributions of the simulated and experimental data relative to theoretical chi-square distributions were performed. Bias and uncertainty errors associated with the spectral estimates were easily identified from the data sets. A model relating the uncertainty and bias errors to the estimates resulted, which aided in determining the appropriateness of the chi-square distribution based confidence intervals. Such confidence intervals were appropriate for nontonally associated frequencies of the experimental data but were inappropriate for tonally associated estimate distributions. The appropriateness at the tonally associated frequencies was indicated by the presence of bias error and noncomformity of the distributions to the theoretical chi-square distribution. A technique for determining appropriate confidence intervals at the tonally associated frequencies was suggested.
EVALUATION OF ANALYTICAL REPORTING ERRORS GENERATED AS DESCRIBED IN SW-846 METHOD 8261A
SW-846 Method 8261A incorporates the vacuum distillation of analytes from samples, and their recoveries are characterized by internal standards. The internal standards measure recoveries with confidence intervals as functions of physical properties. The frequency the calculate...
Using and Evaluating Resampling Simulations in SPSS and Excel.
ERIC Educational Resources Information Center
Smith, Brad
2003-01-01
Describes and evaluates three computer-assisted simulations used with Statistical Package for the Social Sciences (SPSS) and Microsoft Excel. Designed the simulations to reinforce and enhance student understanding of sampling distributions, confidence intervals, and significance tests. Reports evaluations revealed improved student comprehension of…
Zierler, S; Rothman, K J
1985-08-08
To clarify the association of Bendectin and other drugs used in early pregnancy with the occurrence of congenital heart disease, we interviewed 298 mothers of children with congenital heart disease and 738 mothers of healthy controls. Differential recall of drug use by mothers of affected children and mothers of controls was evaluated by comparison of information collected by interview with that recorded in the prenatal record. Data derived from maternal interviews were generally consistent with the record data. Reported Bendectin use was minimally associated with congenital heart disease (prevalence odds ratio, 1.1; 90 per cent confidence interval, 0.8 to 1.5). The data from this study were consistent with previously reported associations of other drugs with congenital heart disease. In particular, aspirin use in early pregnancy was associated with about a twofold increase in the frequency of defects in septation of the truncus arteriosus (prevalence odds ratio, 2.1; 90 per cent confidence interval, 1.1 to 3.9).
Standard Errors and Confidence Intervals of Norm Statistics for Educational and Psychological Tests.
Oosterhuis, Hannah E M; van der Ark, L Andries; Sijtsma, Klaas
2016-11-14
Norm statistics allow for the interpretation of scores on psychological and educational tests, by relating the test score of an individual test taker to the test scores of individuals belonging to the same gender, age, or education groups, et cetera. Given the uncertainty due to sampling error, one would expect researchers to report standard errors for norm statistics. In practice, standard errors are seldom reported; they are either unavailable or derived under strong distributional assumptions that may not be realistic for test scores. We derived standard errors for four norm statistics (standard deviation, percentile ranks, stanine boundaries and Z-scores) under the mild assumption that the test scores are multinomially distributed. A simulation study showed that the standard errors were unbiased and that corresponding Wald-based confidence intervals had good coverage. Finally, we discuss the possibilities for applying the standard errors in practical test use in education and psychology. The procedure is provided via the R function check.norms, which is available in the mokken package.
Jacobson, Isabel G; Smith, Tyler C; Smith, Besa; Keel, Pamela K; Amoroso, Paul J; Wells, Timothy S; Bathalon, Gaston P; Boyko, Edward J; Ryan, Margaret A K
2009-02-15
The effect of military deployments to combat environments on disordered eating and weight changes is unknown. Using longitudinal data from Millennium Cohort Study participants who completed baseline (2001-2003) and follow-up (2004-2006) questionnaires (n=48,378), the authors investigated new-onset disordered eating and weight changes in a large military cohort. Multivariable logistic regression was used to compare these outcomes among those who deployed and reported combat exposures, those who deployed but did not report combat exposures, and those who did not deploy in support of the wars in Iraq and Afghanistan. Deployment was not significantly associated with new-onset disordered eating in women or men, after adjustment for baseline demographic, military, and behavioral characteristics. However, in subgroup comparison analyses of deployers, deployed women reporting combat exposures were 1.78 times more likely to report new-onset disordered eating (95% confidence interval: 1.02, 3.11) and 2.35 times more likely to lose 10% or more of their body weight compared with women who deployed but did not report combat exposures (95% confidence interval: 1.17, 4.70). Despite no significant overall association between deployment and disordered eating and weight changes, deployed women reporting combat exposures represent a subgroup at higher risk for developing eating problems and weight loss.
Phillips, Jane L; Heneka, Nicole; Hickman, Louise; Lam, Lawrence; Shaw, Tim
2014-06-01
Pain is a complex multidimensional phenomenon moderated by consumer, provider and health system factors. Effective pain management cuts across professional boundaries, with failure to screen and assess contributing to the burden of unrelieved pain. To test the impact of an online pain assessment learning module on specialist palliative care nurses' pain assessment competencies, and to determine whether this education impacted positively on palliative care patients' reported pain ratings. A quasi-experimental pain assessment education pilot study utilising 'Qstream © ', an online methodology to deliver 11 case-based pain assessment learning scenarios, developed by an interdisciplinary expert panel and delivered to participants' work emails over a 28-day period in mid-2012. The 'Self-Perceived Pain Assessment Competencies' survey and chart audit data, including patient-reported pain intensity ratings, were collected pre-intervention (T1) and post-intervention (T2) and analysed using inferential statistics to determine key outcomes. Nurses working at two Australian inpatient specialist palliative care services in 2012. The results reported conform to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Guidelines. Participants who completed the education intervention ( n = 34) increased their pain assessment knowledge, assessment tool knowledge and confidence to undertake a pain assessment ( p < 0.001). Participants were more likely to document pain intensity scores in patients' medical records than non-participants (95% confidence interval = 7.3%-22.7%, p = 0.021). There was also a significant reduction in the mean patient-reported pain ratings between the admission and audit date at post-test of 1.5 (95% confidence interval = 0.7-2.3) units in pain score. This pilot confers confidence of the education interventions capacity to improve specialist palliative care nurses' pain assessment practices and to reduce patient-rated pain intensity scores.
ERIC Educational Resources Information Center
Lerner, Matthew D.; Mikami, Amori Yee
2013-01-01
Odgaard and Fowler (2010) articulated the importance of reporting confidence intervals (CIs) on effect size estimates, and they provided useful formulas for doing so. However, one of their reported formulas, pertaining to the calculation of CIs on strength of association effect sizes (e.g., R[squared] or [eta][squared]), is erroneous. This comment…
Hodgkins, Glenn A.; Stewart, Gregory J.; Cohn, Timothy A.; Dudley, Robert W.
2007-01-01
Large amounts of rain fell on southern Maine from the afternoon of April 15, 2007, to the afternoon of April 16, 2007, causing substantial damage to houses, roads, and culverts. This report provides an estimate of the peak flows on two rivers in southern Maine--the Mousam River and the Little Ossipee River--because of their severe flooding. The April 2007 estimated peak flow of 9,230 ft3/s at the Mousam River near West Kennebunk had a recurrence interval between 100 and 500 years; 95-percent confidence limits for this flow ranged from 25 years to greater than 500 years. The April 2007 estimated peak flow of 8,220 ft3/s at the Little Ossipee River near South Limington had a recurrence interval between 100 and 500 years; 95-percent confidence limits for this flow ranged from 50 years to greater than 500 years.
Guida, Pietro; Mastro, Florinda; Scrascia, Giuseppe; Whitlock, Richard; Paparella, Domenico
2014-12-01
A systematic review of the European System for Cardiac Operative Risk Evaluation (euroSCORE) II performance for prediction of operative mortality after cardiac surgery has not been performed. We conducted a meta-analysis of studies based on the predictive accuracy of the euroSCORE II. We searched the Embase and PubMed databases for all English-only articles reporting performance characteristics of the euroSCORE II. The area under the receiver operating characteristic curve, the observed/expected mortality ratio, and observed-expected mortality difference with their 95% confidence intervals were analyzed. Twenty-two articles were selected, including 145,592 procedures. Operative mortality occurred in 4293 (2.95%), whereas the expected events according to euroSCORE II were 4802 (3.30%). Meta-analysis of these studies provided an area under the receiver operating characteristic curve of 0.792 (95% confidence interval, 0.773-0.811), an estimated observed/expected ratio of 1.019 (95% confidence interval, 0.899-1.139), and observed-expected difference of 0.125 (95% confidence interval, -0.269 to 0.519). Statistical heterogeneity was detected among retrospective studies including less recent procedures. Subgroups analysis confirmed the robustness of combined estimates for isolated valve procedures and those combined with revascularization surgery. A significant overestimation of the euroSCORE II with an observed/expected ratio of 0.829 (95% confidence interval, 0.677-0.982) was observed in isolated coronary artery bypass grafting and a slight underestimation of predictions in high-risk patients (observed/expected ratio 1.253 and observed-expected difference 1.859). Despite the heterogeneity, the results from this meta-analysis show a good overall performance of the euroSCORE II in terms of discrimination and accuracy of model predictions for operative mortality. Validation of the euroSCORE II in prospective populations needs to be further studied for a continuous improvement of patients' risk stratification before cardiac surgery. Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.
Yu, Lulu; Kronen, Ryan J; Simon, Laura E; Stoll, Carolyn R T; Colditz, Graham A; Tuuli, Methodius G
2018-02-01
The objective of the study was to assess the effect of prophylactic negative-pressure wound therapy on surgical site infections and other wound complications in women after cesarean delivery. We searched Ovid Medline, Embase, SCOPUS, Cochrane Database of Systematic Reviews, and ClinicalTrials.gov. We included randomized controlled trials and observational studies comparing prophylactic negative-pressure wound therapy with standard wound dressing for cesarean delivery. The primary outcome was surgical site infection after cesarean delivery. Secondary outcomes were composite wound complications, wound dehiscence, wound seroma, endometritis, and hospital readmission. Heterogeneity was assessed using Higgin's I 2 . Relative risks with 95% confidence intervals were calculated using random-effects models. Six randomized controlled trials and 3 cohort studies in high-risk mostly obese women met inclusion criteria and were included in the meta-analysis. Six were full-text articles, 2 published abstracts, and 1 report of trial results in ClinicalTrials.gov. Studies were also heterogeneous in the patients included and type of negative-pressure wound therapy device. The risk of surgical site infection was significantly lower with the use of prophylactic negative-pressure wound therapy compared with standard wound dressing (7 studies: pooled risk ratio, 0.45; 95% confidence interval, 0.31-0.66; adjusted risk ratio, -6.0%, 95% confidence interval, -10.0% to -3.0%; number needed to treat, 17, 95% confidence interval, 10-34). There was no evidence of significant statistical heterogeneity (I 2 = 9.9%) or publication bias (Egger P = .532). Of the secondary outcomes, only composite wound complications were significantly reduced in patients receiving prophylactic negative-pressure wound therapy compared with standard dressing (9 studies: pooled risk ratio, 0.68, 95% confidence interval, 0.49-0.94). Studies on the effectiveness of prophylactic negative-pressure wound therapy at cesarean delivery are heterogeneous but suggest a reduction in surgical site infection and overall wound complications. Larger definitive trials are needed to clarify the clinical utility of prophylactic negative-pressure wound therapy after cesarean delivery. Copyright © 2017 Elsevier Inc. All rights reserved.
Association of Modality with Mortality among Canadian Aboriginals
Hemmelgarn, Brenda; Rigatto, Claudio; Komenda, Paul; Yeates, Karen; Promislow, Steven; Mojica, Julie; Tangri, Navdeep
2012-01-01
Summary Background and objectives Previous studies have shown that Aboriginals and Caucasians experience similar outcome on dialysis in Canada. Using the Canadian Organ Replacement Registry, this study examined whether dialysis modality (peritoneal or hemodialysis) impacted mortality in Aboriginal patients. Design, setting, participants, & measurements This study identified 31,576 adult patients (hemodialysis: Aboriginal=1839, Caucasian=21,430; peritoneal dialysis: Aboriginal=554, Caucasian=6769) who initiated dialysis between January of 2000 and December of 2009. Aboriginal status was identified by self-report. Dialysis modality was determined 90 days after dialysis initiation. Multivariate Cox proportional hazards and competing risk models were constructed to determine the association between race and mortality by dialysis modality. Results During the study period, 939 (51.1%) Aboriginals and 12,798 (53.3%) Caucasians initiating hemodialysis died, whereas 166 (30.0%) and 2037 (30.1%), respectively, initiating peritoneal dialysis died. Compared with Caucasians, Aboriginals on hemodialysis had a comparable risk of mortality (adjusted hazards ratio=1.04, 95% confidence interval=0.96–1.11, P=0.37). However, on peritoneal dialysis, Aboriginals experienced a higher risk of mortality (adjusted hazards ratio=1.36, 95% confidence interval=1.13–1.62, P=0.001) and technique failure (adjusted hazards ratio=1.29, 95% confidence interval=1.03–1.60, P=0.03) than Caucasians. The risk of technique failure varied by patient age, with younger Aboriginals (<50 years old) more likely to develop technique failure than Caucasians (adjusted hazards ratio=1.76, 95% confidence interval=1.23–2.52, P=0.002). Conclusions Aboriginals on peritoneal dialysis experience higher mortality and technique failure relative to Caucasians. Reasons for this race disparity in peritoneal dialysis outcomes are unclear. PMID:22997343
Nationwide Estimates of 30-Day Readmission in Patients With Ischemic Stroke.
Vahidy, Farhaan S; Donnelly, John P; McCullough, Louise D; Tyson, Jon E; Miller, Charles C; Boehme, Amelia K; Savitz, Sean I; Albright, Karen C
2017-05-01
Readmission within 30 days of hospital discharge for ischemic stroke is an important quality of care metric. We aimed to provide nationwide estimates of 30-day readmission in the United States, describe important reasons for readmission, and sought to explore factors associated with 30-day readmission, particularly the association with recanalization therapy. We conducted a weighted analysis of the 2013 Nationwide Readmission Database to represent all US hospitalizations. Adult patients with acute ischemic stroke including those who received intravenous tissue-type plasminogen activator and intra-arterial therapy were identified using International Classification of Diseases -Ninth Revision codes. Readmissions were defined as any readmission during the 30-day post-index hospitalization discharge period for the eligible patient population. Proportions and 95% confidence intervals for overall 30-day readmissions and for unplanned and potentially preventable readmissions are reported. Survey design logistic regression models were fit for determining crude and adjusted odds ratios and 95% confidence interval for association between recanalization therapy and 30-day readmission. Of the 319 317 patients with acute ischemic stroke, 12.1% (95% confidence interval, 11.9-12.3) were readmitted. Of these, 89.6% were unplanned and 12.9% were potentially preventable. More than 20% of all readmissions were attributable to acute cerebrovascular disease. Readmitted patients were older and had a higher comorbidity burden. After controlling for age, sex, insurance status, and comorbidities, patients who underwent recanalization therapy had significantly lower odds of 30-day readmission (odds ratio, 0.82; 95% confidence interval, 0.77-0.89). Up to 12% of patients with ischemic stroke get readmitted within 30 days post-discharge period, and recanalization therapy is associated with 11% to 23% lower odds of 30-day readmission. © 2017 American Heart Association, Inc.
Age-Specific Sex Differences in Magnetic Resonance Imaging-Depicted Carotid Intraplaque Hemorrhage.
Singh, Navneet; Moody, Alan R; Zhang, Bowen; Kaminski, Isabella; Kapur, Kush; Chiu, Stephanie; Tyrrell, Pascal N
2017-08-01
Stroke rates are higher in men compared with women in the fourth through seventh decades of life, and higher rates may result from differences in carotid intraplaque hemorrhage (IPH), an unstable atherosclerotic plaque component. We report age-specific sex differences in the presence of magnetic resonance imaging-depicted carotid IPH. Patients (n=1115) underwent magnetic resonance imaging for carotid IPH between 2005 and 2014. Low-grade carotid stenosis patients (n=906) without prior endarterectomy were eligible for this cross-sectional study. Of the 906 patients included (mean age±SD in years, 66.98±15.15), 63 (6.95%) had carotid IPH. In men and women, carotid IPH was present in 11.43% (48 of 420) and 3.09% (15 of 486), respectively ( P <0.0001). Multivariable logistic regression analysis confirmed greater odds of carotid IPH in men for all ages: 45 to 54 (odds ratio=45.45; 95% confidence interval, 3.43-500), 55 to 64 years (odds ratio=21.74; 95% confidence interval, 3.21-142.86), 65 to 74 years (odds ratio=10.42; 95% confidence interval, 2.91-37.04), and ≥75 years (odds ratio=5.00; 95% confidence interval, 2.31-10.75). Male sex modified the effect of age on the presence of carotid IPH (β=0.074; SE=0.036; P =0.0411). Men have greater age-specific odds of magnetic resonance imaging-depicted carotid IPH compared with women. With increasing age post-menopause, the odds of carotid IPH in women becomes closer to that of men. Delayed onset of carotid IPH in women, an unstable plaque component, may partly explain differential stroke rates between sexes, and further studies are warranted. © 2017 American Heart Association, Inc.
Chiu, Hsien-Yi; Chang, Wei-Lun; Tsai, Tsen-Fang; Tsai, Yi-Wen; Shiu, Ming-Neng
2018-03-01
Several case studies have reported an association between antifungal drug use and psoriasis risk. The objective of this study was to investigate the association between terbinafine/itraconazole exposure and psoriasis incidence. Among patients with onychomycosis in the Taiwan National Health Insurance Research Database, 3831 incident psoriasis cases were identified during 2004-2010 and compared with 3831 age- and sex-matched controls with the same look-back period. Multivariate conditional logistic regression was used for the analysis. The psoriasis cases were significantly more likely than matched controls to have used terbinafine or itraconazole (59.85 vs. 42.70%, respectively; p < 0.0001). After adjusting for potential confounders and cumulative duration of antifungal drug prescription, terbinafine/itraconazole use was associated with an increased psoriasis risk (adjusted odds ratio 1.33, 95% confidence interval 1.15-1.54). The association was stronger for more recent drug exposure (adjusted odds ratio 2.96, 95% confidence interval 2.25-3.90 for ≤ 90 days before the sampling date; adjusted odds ratio 1.04, 95% confidence interval 0.89-1.22 for > 360 days). In a comparison of patients receiving terbinafine or itraconazole only, psoriasis risk was higher for itraconazole (adjusted odds ratio 1.21, 95% confidence interval 1.05-1.40). This large population-based case-control analysis showed that exposure to terbinafine or itraconazole is associated with an increased risk of incident psoriasis. The finding of an increased psoriasis risk for antifungal drug users, particularly for itraconazole, deserves attention in clinical practice although further prospective studies are necessary to confirm our findings and clarify the biological mechanisms that underlie these associations.
Gourraud, Jean-Baptiste; Chaix, Marie-A; Shohoudi, Azadeh; Pagé, Pierre; Dubuc, Marc; Thibault, Bernard; Poirier, Nancy C; Dore, Annie; Marcotte, François; Mongeon, François-Pierre; Asgar, Anita W; Ibrahim, Réda; Khairy, Paul; Mondésert, Blandine
2018-02-01
Safety and feasibility data on transvenous lead extraction (TLE) in the challenging population of adults with congenital heart disease (A-CHD) are limited. Herein, we report the results of TLE in A-CHD during a 20-year period. All consecutive TLE procedures in A-CHD were included in a monocentric prospective registry from 1996. A total of 121 leads were extracted in 49 A-CHD (median age, 38 years; 51% men) during 71 TLE procedures. Twenty-four (49%) patients had transposition of the great arteries. Main indications for extraction were infection in 34 (48%) and lead failure in 22 (31%). A laser sheath was required for 56 (46%) leads and a femoral approach for 10 (8%). Complete TLE was achieved for 111 leads (92%). In multivariable analysis, lead duration (odds ratio, 1.02; 95% confidence interval, 1.00-1.04; P <0.01) and number of previous cardiac surgeries (odds ratio, 2.65; 95% confidence interval, 1.52-4.67; P <0.01) were predictive of TLE failure. No perioperative death or pericardial effusion was observed. Subpulmonary atrioventricular valve regurgitation increased in 8 patients (5 with transposition of the great arteries) and was independently associated with an implantable cardioverter defibrillator lead (odds ratio, 9.69; 95% confidence interval, 1.31-71.64; P =0.03) and valvular vegetation (odds ratio, 7.29; 95% confidence interval, 1.32-40.51; P =0.02). After a median of 54 (19-134) months of follow-up after the first TLE, 3 deaths occurred independently from lead management. Despite complex anatomic issues, TLE can be achieved successfully in most A-CHD using advanced extraction techniques. Subpulmonary atrioventricular valve regurgitation is a prevalent complication, particularly in patients with transposition of the great arteries. © 2018 American Heart Association, Inc.
Magro-Malosso, Elena R; Saccone, Gabriele; Di Tommaso, Mariarosaria; Roman, Amanda; Berghella, Vincenzo
2017-08-01
Gestational hypertensive disorders, including gestational hypertension and preeclampsia, are one of the leading causes of maternal morbidity and mortality. The aim of our study was to evaluate the effect of exercise during pregnancy on the risk of gestational hypertensive disorders. Electronic databases were searched from their inception to February 2017. Selection criteria included only randomized controlled trials of uncomplicated pregnant women assigned before 23 weeks to an aerobic exercise regimen or not. The summary measures were reported as relative risk with 95% confidence intervals. The primary outcome was the incidence of gestational hypertensive disorders, defined as either gestational hypertension or preeclampsia. Seventeen trials, including 5075 pregnant women, were analyzed. Of them, seven contributed data to quantitative meta-analysis for the primary outcome. Women who were randomized in early pregnancy to aerobic exercise for about 30-60 min two to seven times per week had a significant lower incidence of gestational hypertensive disorders (5.9% vs. 8.5%; relative risk 0.70, 95% confidence interval 0.53-0.83; seven studies, 2517 participants), specifically a lower incidence of gestational hypertension (2.5% vs. 4.6%; relative risk 0.54, 95% confidence interval 0.40-0.74; 16 studies, 4641 participants) compared with controls. The incidence of preeclampsia (2.3% vs. 2.8%; relative risk 0.79, 95% confidence interval 0.45-1.38; six studies, 2230 participants) was similar in both groups. The incidence of cesarean delivery was decreased by 16% in the exercise group. Aerobic exercise for about 30-60 min two to seven times per week during pregnancy, as compared with being more sedentary, is associated with a significantly reduced risk of gestational hypertensive disorders overall, gestational hypertension, and cesarean delivery. © 2017 Nordic Federation of Societies of Obstetrics and Gynecology.
Yohanna, Seychelle; Alkatheeri, Ali M.A.; Brimble, Scott K.; McCormick, Brendan; Iansavitchous, Arthur; Blake, Peter G.
2015-01-01
Background and objectives Neutral-pH, low–glucose degradation products solutions were developed in an attempt to lessen the adverse effects of conventional peritoneal dialysis solutions. A systematic review was performed evaluating the effect of these solutions on residual renal function, urine volume, peritoneal ultrafiltration, and peritoneal small-solute transport (dialysate to plasma creatinine ratio) over time. Design, setting, participants, & measurements Multiple electronic databases were searched from January of 1995 to January of 2013. Randomized trials reporting on any of four prespecified outcomes were selected by consensus among multiple reviewers. Results Eleven trials of 643 patients were included. Trials were generally of poor quality. The meta-analysis was performed using a random effects model. The use of neutral-pH, low-glucose degradation products solutions resulted in better preserved residual renal function at various study durations, including >1 year (combined analysis: 11 studies; 643 patients; standardized mean difference =0.17 ml/min; 95% confidence interval, 0.01 to 0.32), and greater urine volumes (eight studies; 598 patients; mean difference =128 ml/d; 95% confidence interval, 58 to 198). There was no significant difference in peritoneal ultrafiltration (seven studies; 571 patients; mean difference =−110; 95% confidence interval, −312 to 91) or dialysate to plasma creatinine ratio (six studies; 432 patients; mean difference =0.03; 95% confidence interval, 0.00 to 0.06). Conclusions The use of neutral-pH, low–glucose degradation products solutions results in better preservation of residual renal function and greater urine volumes. The effect on residual renal function occurred early and persisted beyond 12 months. Additional studies are required to evaluate the use of neutral-pH, low–glucose degradation products solutions on hard clinical outcomes. PMID:26048890
Moro, M L; Salamina, G; Gori, A; Penati, V; Sacchetti, R; Mezzetti, F; Infuso, A; Sodano, L
2002-02-01
A 2-year, population-based, molecular epidemiological study was conducted in Milan, Italy, to determine the proportion of tuberculosis (TB) cases attributable to recent transmission. All strains were typed by restriction fragment length polymorphism (RFLP) analysis; clustering was considered indicative of recent transmission. Of the 581 cases, 239 (41.1%) belonged to clusters that consisted of 2 to 11 patients; 28.1% were attributable to recent transmission (number of clustered patients minus 1). Clustering was associated with multidrug-resistant Mycobacterium tuberculosis strains (74.2% of cases), AIDS (60.2%), and a history of incarceration (67.4%). The frequency of multidrug-resistant Mycobacterium tuberculosis was 5.3% overall (15.4% among AIDS patients). Among AIDS patients, infection with a resistant strain was independently associated with clustering (odds ratio, 1.32; 95% confidence interval, 1.07-1.163), while among non-AIDS patients, three factors were associated with clustering: history of incarceration (odds ratio, 2.03; 95% confidence interval, 1.41-2.92), age <30 years (odds ratio, 1.43; 95% confidence interval, 1.05-1.94), and native-born Italian nationality (odds ratio, 1.44; 95% confidence interval, 1.08-1.92). Of the 118 patients who belonged to either the smallest or the largest cluster, 19 (16.1%) reported an epidemiological link with another study patient. The results of this study highlight the need for control programs that focus on selected high-risk groups consisting primarily of HIV-infected individuals and persons with social and lifestyle risks for TB. These programs should be aimed at reducing the probability of transmission of drug-resistant TB through early identification of cases and provision of effective treatment until the individual is cured.
Hunter, Jessica Ezzell; Allen, Emily Graves; Shin, Mikyong; Bean, Lora J H; Correa, Adolfo; Druschel, Charlotte; Hobbs, Charlotte A; O'Leary, Leslie A; Romitti, Paul A; Royle, Marjorie H; Torfs, Claudine P; Freeman, Sallie B; Sherman, Stephanie L
2013-09-01
Advanced maternal age and altered recombination are known risk factors for Down syndrome cases due to maternal nondisjunction of chromosome 21, whereas the impact of other environmental and genetic factors is unclear. The aim of this study was to investigate an association between low maternal socioeconomic status and chromosome 21 nondisjunction. Data from 714 case and 977 control families were used to assess chromosome 21 meiosis I and meiosis II nondisjunction errors in the presence of three low socioeconomic status factors: (i) both parents had not completed high school, (ii) both maternal grandparents had not completed high school, and (iii) an annual household income of <$25,000. We applied logistic regression models and adjusted for covariates, including maternal age and race/ethnicity. As compared with mothers of controls (n = 977), mothers with meiosis II chromosome 21 nondisjunction (n = 182) were more likely to have a history of one low socioeconomic status factor (odds ratio = 1.81; 95% confidence interval = 1.07-3.05) and ≥2 low socioeconomic status factors (odds ratio = 2.17; 95% confidence interval = 1.02-4.63). This association was driven primarily by having a low household income (odds ratio = 1.79; 95% confidence interval = 1.14-2.73). The same statistically significant association was not detected among maternal meiosis I errors (odds ratio = 1.31; 95% confidence interval = 0.81-2.10), in spite of having a larger sample size (n = 532). We detected a significant association between low maternal socioeconomic status and meiosis II chromosome 21 nondisjunction. Further studies are warranted to explore which aspects of low maternal socioeconomic status, such as environmental exposures or poor nutrition, may account for these results.
Abnormal P-Wave Axis and Ischemic Stroke: The ARIC Study (Atherosclerosis Risk In Communities).
Maheshwari, Ankit; Norby, Faye L; Soliman, Elsayed Z; Koene, Ryan J; Rooney, Mary R; O'Neal, Wesley T; Alonso, Alvaro; Chen, Lin Y
2017-08-01
Abnormal P-wave axis (aPWA) has been linked to incident atrial fibrillation and mortality; however, the relationship between aPWA and stroke has not been reported. We hypothesized that aPWA is associated with ischemic stroke independent of atrial fibrillation and other stroke risk factors and tested our hypothesis in the ARIC study (Atherosclerosis Risk In Communities), a community-based prospective cohort study. We included 15 102 participants (aged 54.2±5.7 years; 55.2% women; 26.5% blacks) who attended the baseline examination (1987-1989) and without prevalent stroke. We defined aPWA as any value outside 0 to 75° using 12-lead ECGs obtained during study visits. Each case of incident ischemic stroke was classified in accordance with criteria from the National Survey of Stroke by a computer algorithm and adjudicated by physician review. Multivariable Cox regression was used to estimate hazard ratios and 95% confidence intervals for the association of aPWA with stroke. During a mean follow-up of 20.2 years, there were 657 incident ischemic stroke cases. aPWA was independently associated with a 1.50-fold (95% confidence interval, 1.22-1.85) increased risk of ischemic stroke in the multivariable model that included atrial fibrillation. When subtyped, aPWA was associated with a 2.04-fold (95% confidence interval, 1.42-2.95) increased risk of cardioembolic stroke and a 1.32-fold (95% confidence interval, 1.03-1.71) increased risk of thrombotic stroke. aPWA is independently associated with ischemic stroke. This association seems to be stronger for cardioembolic strokes. Collectively, our findings suggest that alterations in atrial electric activation may predispose to cardiac thromboembolism independent of atrial fibrillation. © 2017 American Heart Association, Inc.
Cardiac rehabilitation after percutaneous coronary intervention: Results from a nationwide survey.
Olsen, Siv Js; Schirmer, Henrik; Bønaa, Kaare H; Hanssen, Tove A
2018-03-01
The purpose of this study was to estimate the proportion of Norwegian coronary heart disease patients participating in cardiac rehabilitation programmes after percutaneous coronary intervention, and to determine predictors of cardiac rehabilitation participation. Participants were patients enrolled in the Norwegian Coronary Stent Trial. We assessed cardiac rehabilitation participation in 9013 of these patients who had undergone their first percutaneous coronary intervention during 2008-2011. Of these, 7068 patients (82%) completed a self-administered questionnaire on cardiac rehabilitation participation within three years after their percutaneous coronary intervention. Twenty-eight per cent of the participants reported engaging in cardiac rehabilitation. Participation rate differed among the four regional health authorities in Norway, varying from 20%-31%. Patients undergoing percutaneous coronary intervention for an acute coronary syndrome were more likely to participate in cardiac rehabilitation than patients with stable angina (odds ratio 3.2; 95% confidence interval 2.74-3.76). A multivariate statistical model revealed that men had a 28% lower probability ( p<0.001) of participating in cardiac rehabilitation, and the odds of attending cardiac rehabilitation decreased with increasing age ( p<0.001). Contributors to higher odds of cardiac rehabilitation participation were educational level >12 years (odds ratio 1.50; 95% confidence interval 1.32-1.71) and body mass index>25 (odds ratio 1.19; 95% confidence interval 1.05-1.36). Prior coronary artery bypass graft was associated with lower odds of cardiac rehabilitation participation (odds ratio 0.47; 95% confidence interval 0.32-0.70) Conclusion: The estimated cardiac rehabilitation participation rate among patients undergoing first-time percutaneous coronary intervention is low in Norway. The typical participant is young, overweight, well-educated, and had an acute coronary event. These results varied by geographical region.
Relationship between daily exposure to biomass fuel smoke and blood pressure in high-altitude Peru.
Burroughs Peña, Melissa; Romero, Karina M; Velazquez, Eric J; Davila-Roman, Victor G; Gilman, Robert H; Wise, Robert A; Miranda, J Jaime; Checkley, William
2015-05-01
Household air pollution from biomass fuel use affects 3 billion people worldwide; however, few studies have examined the relationship between biomass fuel use and blood pressure. We sought to determine if daily biomass fuel use was associated with elevated blood pressure in high altitude Peru and if this relationship was affected by lung function. We analyzed baseline information from a population-based cohort study of adults aged ≥ 35 years in Puno, Peru. Daily biomass fuel use was self-reported. We used multivariable regression models to examine the relationship between daily exposure to biomass fuel smoke and blood pressure outcomes. Interactions with sex and quartiles of forced vital capacity were conducted to evaluate for effect modification. Data from 1004 individuals (mean age, 55.3 years; 51.7% women) were included. We found an association between biomass fuel use with both prehypertension (adjusted relative risk ratio, 5.0; 95% confidence interval, 2.6-9.9) and hypertension (adjusted relative risk ratio, 3.5; 95% confidence interval, 1.7-7.0). Biomass fuel users had a higher systolic blood pressure (7.0 mm Hg; 95% confidence interval, 4.4-9.6) and a higher diastolic blood pressure (5.9 mm Hg; 95% confidence interval, 4.2-7.6) when compared with nonusers. We did not find interaction effects between daily biomass fuel use and sex or percent predicted forced vital capacity for either systolic blood pressure or diastolic blood pressure. Biomass fuel use was associated with a higher likelihood of having hypertension and higher blood pressure in Peru. Reducing exposure to household air pollution from biomass fuel use represents an opportunity for cardiovascular prevention. © 2015 American Heart Association, Inc.
Alternative methods to evaluate trial level surrogacy.
Abrahantes, Josè Cortiñas; Shkedy, Ziv; Molenberghs, Geert
2008-01-01
The evaluation and validation of surrogate endpoints have been extensively studied in the last decade. Prentice [1] and Freedman, Graubard and Schatzkin [2] laid the foundations for the evaluation of surrogate endpoints in randomized clinical trials. Later, Buyse et al. [5] proposed a meta-analytic methodology, producing different methods for different settings, which was further studied by Alonso and Molenberghs [9], in their unifying approach based on information theory. In this article, we focus our attention on the trial-level surrogacy and propose alternative procedures to evaluate such surrogacy measure, which do not pre-specify the type of association. A promising correction based on cross-validation is investigated. As well as the construction of confidence intervals for this measure. In order to avoid making assumption about the type of relationship between the treatment effects and its distribution, a collection of alternative methods, based on regression trees, bagging, random forests, and support vector machines, combined with bootstrap-based confidence interval and, should one wish, in conjunction with a cross-validation based correction, will be proposed and applied. We apply the various strategies to data from three clinical studies: in opthalmology, in advanced colorectal cancer, and in schizophrenia. The results obtained for the three case studies are compared; they indicate that using random forest or bagging models produces larger estimated values for the surrogacy measure, which are in general stabler and the confidence interval narrower than linear regression and support vector regression. For the advanced colorectal cancer studies, we even found the trial-level surrogacy is considerably different from what has been reported. In general the alternative methods are more computationally demanding, and specially the calculation of the confidence intervals, require more computational time that the delta-method counterpart. First, more flexible modeling techniques can be used, allowing for other type of association. Second, when no cross-validation-based correction is applied, overly optimistic trial-level surrogacy estimates will be found, thus cross-validation is highly recommendable. Third, the use of the delta method to calculate confidence intervals is not recommendable since it makes assumptions valid only in very large samples. It may also produce range-violating limits. We therefore recommend alternatives: bootstrap methods in general. Also, the information-theoretic approach produces comparable results with the bagging and random forest approaches, when cross-validation correction is applied. It is also important to observe that, even for the case in which the linear model might be a good option too, bagging methods perform well too, and their confidence intervals were more narrow.
Overconfidence over the lifespan
Prims, Julia P.; Moore, Don A.
2018-01-01
This research investigated how different forms of overconfidence correlate with age. Contrary to stereotypes that young people are more overconfident, the results provide little evidence that overestimation of one’s performance or overplacement of one’s performance relative to that of others is correlated with age. Instead, the results suggest that precision in judgment (confidence that one knows the truth) increases with age. This result is strongest for probabilistic elicitations, and not present in quantile elicitations or reported confidence intervals. The results suggest that a lifetime of experience, rather than leading to better calibration, instead may increase our confidence that we know what we’re talking about. PMID:29861807
2013-11-01
Ptrend 0.78 0.62 0.75 Unconditional logistic regression was used to estimate odds ratios (OR) and 95 % confidence intervals (CI) for risk of node...Ptrend 0.71 0.67 Unconditional logistic regression was used to estimate odds ratios (OR) and 95 % confidence intervals (CI) for risk of high-grade tumors... logistic regression was used to estimate odds ratios (OR) and 95 % confidence intervals (CI) for the associations between each of the seven SNPs and
Wintermann, Gloria-Beatrice; Weidner, Kerstin; Strauß, Bernhard; Rosendahl, Jenny; Petrowski, Katja
2016-12-01
Prolonged mechanical ventilation for acute medical conditions increases the risk of chronic critical illness (CCI). Close family members are confronted with the life-threatening condition of the CCI patients and are prone to develop posttraumatic stress disorder affecting their health-related quality of life (HRQL). Main aim of the present study was to investigate patient- and family-related risk factors for posttraumatic stress and decreased HRQL in family members of CCI patients. In a cross-sectional design nested within a prospective longitudinal cohort study, posttraumatic stress symptoms and quality of life were assessed in family members of CCI patients (n = 83, aged between 18 and 72 years) up to 6 months after transfer from ICU at acute care hospital to post-acute rehabilitation. Patients admitted a large rehabilitation hospital for ventilator weaning. The Posttraumatic Stress Scale-10 and the Euro-Quality of life-5D-3L were applied in both patients and their family members via telephone interview. A significant proportion of CCI patients and their family members (14.5 and 15.7 %, respectively) showed clinically relevant scores of posttraumatic stress. Both CCI patients and family members reported poorer HRQL than a normative sample. Factors independently associated with posttraumatic stress in family members were the time following ICU discharge (β = .256, 95 % confidence interval .053-.470) and the patients' diagnosis of PTSD (β = .264, 95 % confidence interval .045-.453). Perceived satisfaction with the relationship turned out to be a protective factor for posttraumatic stress in family members of CCI patients (β = -.231, 95 % confidence interval -.423 to -.015). Regarding HRQL in family members, patients' acute posttraumatic stress at ICU (β = -.290, 95 % confidence interval -.360 to -.088) and their own posttraumatic stress 3 to 6 months post-transfer (β = -.622, 95 % confidence interval -.640 to -.358) turned out to be significant predictors. Posttraumatic stress and HRQL should be routinely assessed in family members of CCI patients at regular intervals starting early at ICU. Preventive family-centered interventions are needed to improve posttraumatic stress and HRQL in both patients and their family members.
Rocca, Corinne H; Thompson, Kirsten M J; Goodman, Suzan; Westhoff, Carolyn L; Harper, Cynthia C
2016-06-01
Almost one-half of women having an abortion in the United States have had a previous procedure, which highlights a failure to provide adequate preventive care. Provision of intrauterine devices and implants, which have high upfront costs, can be uniquely challenging in the abortion care setting. We conducted a study of a clinic-wide training intervention on long-acting reversible contraception and examined the effect of the intervention, insurance coverage, and funding policies on the use of long-acting contraceptives after an abortion. This subanalysis of a cluster, randomized trial examines data from the 648 patients who had undergone an abortion who were recruited from 17 reproductive health centers across the United States. The trial followed participants 18-25 years old who did not desire pregnancy for a year. We measured the effect of the intervention, health insurance, and funding policies on contraceptive outcomes, which included intrauterine device and implant counseling and selection at the abortion visit, with the use of logistic regression with generalized estimating equations for clustering. We used survival analysis to model the actual initiation of these methods over 1 year. Women who obtained abortion care at intervention sites were more likely to report intrauterine device and implant counseling (70% vs 41%; adjusted odds ratio, 3.83; 95% confidence interval, 2.37-6.19) and the selection of these methods (36% vs 21%; adjusted odds ratio, 2.11; 95% confidence interval, 1.39-3.21). However, the actual initiation of methods was similar between study arms (22/100 woman-years each; adjusted hazard ratio, 0.88; 95% confidence interval, 0.51-1.51). Health insurance and funding policies were important for the initiation of intrauterine devices and implants. Compared with uninsured women, those women with public health insurance had a far higher initiation rate (adjusted hazard ratio, 2.18; 95% confidence interval, 1.31-3.62). Women at sites that provide state Medicaid enrollees abortion coverage also had a higher initiation rate (adjusted hazard ratio, 1.73; 95% confidence interval, 1.04-2.88), as did those at sites with state mandates for private health insurance to cover contraception (adjusted hazard ratio, 1.80; 95% confidence interval, 1.06-3.07). Few of the women with private insurance used it to pay for the abortion (28%), but those who did initiated long-acting contraceptive methods at almost twice the rate as women who paid for it themselves or with donated funds (adjusted hazard ratio, 1.94; 95% confidence interval, 1.10-3.43). The clinic-wide training increased long-acting reversible contraceptive counseling and selection but did not change initiation for abortion patients. Long-acting method use after abortion was associated strongly with funding. Restrictions on the coverage of abortion and contraceptives in abortion settings prevent the initiation of desired long-acting methods. Copyright © 2015 Elsevier Inc. All rights reserved.
Closed-form confidence intervals for functions of the normal mean and standard deviation.
Donner, Allan; Zou, G Y
2012-08-01
Confidence interval methods for a normal mean and standard deviation are well known and simple to apply. However, the same cannot be said for important functions of these parameters. These functions include the normal distribution percentiles, the Bland-Altman limits of agreement, the coefficient of variation and Cohen's effect size. We present a simple approach to this problem by using variance estimates recovered from confidence limits computed for the mean and standard deviation separately. All resulting confidence intervals have closed forms. Simulation results demonstrate that this approach performs very well for limits of agreement, coefficients of variation and their differences.
2013-01-01
Background The phenomenon of inequitable healthcare utilization in rural China interests policymakers and researchers; however, the inequity has not been actually measured to present the magnitude and trend using nationally representative data. Methods Based on the National Health Service Survey (NHSS) in 1993, 1998, 2003, and 2008, the Probit model with the probability of outpatient visit and the probability of inpatient visit as the dependent variables is applied to estimate need-predicted healthcare utilization. Furthermore, need-standardized healthcare utilization is assessed through indirect standardization method. Concentration index is measured to reflect income-related inequity of healthcare utilization. Results The concentration index of need-standardized outpatient utilization is 0.0486[95% confidence interval (0.0399, 0.0574)], 0.0310[95% confidence interval (0.0229, 0.0390)], 0.0167[95% confidence interval (0.0069, 0.0264)] and −0.0108[95% confidence interval (−0.0213, -0.0004)] in 1993, 1998, 2003 and 2008, respectively. For inpatient service, the concentration index is 0.0529[95% confidence interval (0.0349, 0.0709)], 0.1543[95% confidence interval (0.1356, 0.1730)], 0.2325[95% confidence interval (0.2132, 0.2518)] and 0.1313[95% confidence interval (0.1174, 0.1451)] in 1993, 1998, 2003 and 2008, respectively. Conclusions Utilization of both outpatient and inpatient services was pro-rich in rural China with the exception of outpatient service in 2008. With the same needs for healthcare, rich rural residents utilized more healthcare service than poor rural residents. Compared to utilization of outpatient service, utilization of inpatient service was more inequitable. Inequity of utilization of outpatient service reduced gradually from 1993 to 2008; meanwhile, inequity of inpatient service utilization increased dramatically from 1993 to 2003 and decreased significantly from 2003 to 2008. Recent attempts in China to increase coverage of insurance and primary healthcare could be a contributing factor to counteract the inequity of outpatient utilization, but better benefit packages and delivery strategies still need to be tested and scaled up to reduce future inequity in inpatient utilization in rural China. PMID:23688260
Exposure to power frequency electric fields and the risk of childhood cancer in the UK
Skinner, J; Mee, T J; Blackwell, R P; Maslanyj, M P; Simpson, J; Allen, S G; Day, N E
2002-01-01
The United Kingdom Childhood Cancer Study, a population-based case–control study covering the whole of Great Britain, incorporated a pilot study measuring electric fields. Measurements were made in the homes of 473 children who were diagnosed with a malignant neoplasm between 1992 and 1996 and who were aged 0–14 at diagnosis, together with 453 controls matched on age, sex and geographical location. Exposure assessments comprised resultant spot measurements in the child's bedroom and the family living-room. Temporal stability of bedroom fields was investigated through continuous logging of the 48-h vertical component at the child's bedside supported by repeat spot measurements. The principal exposure metric used was the mean of the pillow and bed centre measurements. For the 273 cases and 276 controls with fully validated measures, comparing those with a measured electric field exposure ⩾20 V m−1 to those in a reference category of exposure <10 V m−1, odds ratios of 1.31 (95% confidence interval 0.68–2.54) for acute lymphoblastic leukaemia, 1.32 (95% confidence interval 0.73–2.39) for total leukaemia, 2.12 (95% confidence interval 0.78–5.78) for central nervous system cancers and 1.26 (95% confidence interval 0.77–2.07) for all malignancies were obtained. When considering the 426 cases and 419 controls with no invalid measures, the corresponding odds ratios were 0.86 (95% confidence interval 0.49–1.51) for acute lymphoblastic leukaemia, 0.93 (95% confidence interval 0.56–1.54) for total leukaemia, 1.43 (95% confidence interval 0.68–3.02) for central nervous system cancers and 0.90 (95% confidence interval 0.59–1.35) for all malignancies. With exposure modelled as a continuous variable, odds ratios for an increase in the principal metric of 10 V m−1 were close to unity for all disease categories, never differing significantly from one. British Journal of Cancer (2002) 87, 1257–1266. doi:10.1038/sj.bjc.6600602 www.bjcancer.com © 2002 Cancer Research UK PMID:12439715
Lo, Monica Y; Bonthala, Nirupama; Holper, Elizabeth M; Banks, Kamakki; Murphy, Sabina A; McGuire, Darren K; de Lemos, James A; Khera, Amit
2013-03-15
Women with angina pectoris and abnormal stress test findings commonly have no epicardial coronary artery disease (CAD) at catheterization. The aim of the present study was to develop a risk score to predict obstructive CAD in such patients. Data were analyzed from 337 consecutive women with angina pectoris and abnormal stress test findings who underwent cardiac catheterization at our center from 2003 to 2007. Forward selection multivariate logistic regression analysis was used to identify the independent predictors of CAD, defined by ≥50% diameter stenosis in ≥1 epicardial coronary artery. The independent predictors included age ≥55 years (odds ratio 2.3, 95% confidence interval 1.3 to 4.0), body mass index <30 kg/m(2) (odds ratio 1.9, 95% confidence interval 1.1 to 3.1), smoking (odds ratio 2.6, 95% confidence interval 1.4 to 4.8), low high-density lipoprotein cholesterol (odds ratio 2.9, 95% confidence interval 1.5 to 5.5), family history of premature CAD (odds ratio 2.4, 95% confidence interval 1.0 to 5.7), lateral abnormality on stress imaging (odds ratio 2.8, 95% confidence interval 1.5 to 5.5), and exercise capacity <5 metabolic equivalents (odds ratio 2.4, 95% confidence interval 1.1 to 5.6). Assigning each variable 1 point summed to constitute a risk score, a graded association between the score and prevalent CAD (ptrend <0.001). The risk score demonstrated good discrimination with a cross-validated c-statistic of 0.745 (95% confidence interval 0.70 to 0.79), and an optimized cutpoint of a score of ≤2 included 62% of the subjects and had a negative predictive value of 80%. In conclusion, a simple clinical risk score of 7 characteristics can help differentiate those more or less likely to have CAD among women with angina pectoris and abnormal stress test findings. This tool, if validated, could help to guide testing strategies in women with angina pectoris. Copyright © 2013 Elsevier Inc. All rights reserved.
Yee, Lynn M; Caughey, Aaron B; Cheng, Yvonne W
2017-09-01
Gestational weight gain above or below the 2009 National Academy of Medicine guidelines has been associated with adverse maternal and neonatal outcomes. Although it has been well established that excess gestational weight gain is associated with the development of gestational hypertension and preeclampsia, the relationship between gestational weight gain and adverse perinatal outcomes among women with pregestational (chronic) hypertension is less clear. The objective of this study was to examine the relationship between gestational weight gain above and below National Academy of Medicine guidelines and perinatal outcomes in a large, population-based cohort of women with chronic hypertension. This is a population-based retrospective cohort study of women with chronic hypertension who had term, singleton, vertex births in the United States from 2012 through 2014. Prepregnancy body mass index was calculated using self-reported prepregnancy weight and height. Women were categorized into 4 groups based on gestational weight gain and prepregnancy body mass index: (1) weight gain less than, (2) weight gain within, (3) weight gain 1-19 lb in excess of, and (4) weight gain ≥20 lb in excess of the National Academy of Medicine guidelines. The χ 2 tests and multivariable logistic regression analysis were used for statistical comparisons. Stratified analyses by body mass index category were additionally performed. In this large birth cohort, 101,259 women met criteria for inclusion. Compared to hypertensive women who had gestational weight gain within guidelines, hypertensive women with weight gain ≥20 lb over National Academy of Medicine guidelines were more likely to have eclampsia (adjusted odds ratio, 1.93; 95% confidence interval, 1.54-2.42) and cesarean delivery (adjusted odds ratio, 1.60; 95% confidence interval, 1.50-1.70). Excess weight gain ≥20 lb over National Academy of Medicine guidelines was also associated with increased odds of 5-minute Apgar <7 (adjusted odds ratio, 1.29; 95% confidence interval, 1.13-1.47), neonatal intensive care unit admission (adjusted odds ratio, 1.23; 95% confidence interval, 1.14-1.33), and large-for-gestational-age neonates (adjusted odds ratio, 2.41; 95% confidence interval, 2.27-2.56) as well as decreased odds of small-for-gestational-age status (adjusted odds ratio, 0.52; 95% confidence interval, 0.46-0.58). Weight gain 1-19 lb over guidelines was associated with similar fetal growth outcomes although with a smaller effect size. In contrast, weight gain less than National Academy of Medicine guidelines was not associated with adverse maternal outcomes but was associated with increased odds of small for gestational age (adjusted odds ratio, 1.31; 95% confidence interval, 1.21-1.52) and decreased odds of large-for-gestational-age status (adjusted odds ratio, 0.86; 95% confidence interval, 0.81-0.92). Analysis of maternal and neonatal outcomes stratified by body mass index demonstrated similar findings. Women with chronic hypertension who gain less weight than National Academy of Medicine guidelines experience increased odds of small-for-gestational-age neonates, whereas excess weight gain ≥20 lb over National Academy of Medicine guidelines is associated with cesarean delivery, eclampsia, 5-minute Apgar <7, neonatal intensive care unit admission, and large-for-gestational-age neonates. Copyright © 2017 Elsevier Inc. All rights reserved.
Confidence Intervals for True Scores Using the Skew-Normal Distribution
ERIC Educational Resources Information Center
Garcia-Perez, Miguel A.
2010-01-01
A recent comparative analysis of alternative interval estimation approaches and procedures has shown that confidence intervals (CIs) for true raw scores determined with the Score method--which uses the normal approximation to the binomial distribution--have actual coverage probabilities that are closest to their nominal level. It has also recently…
ERIC Educational Resources Information Center
Hansson, Patrik; Juslin, Peter; Winman, Anders
2008-01-01
Research with general knowledge items demonstrates extreme overconfidence when people estimate confidence intervals for unknown quantities, but close to zero overconfidence when the same intervals are assessed by probability judgment. In 3 experiments, the authors investigated if the overconfidence specific to confidence intervals derives from…
Colon cancer in Chile before and after the start of the flour fortification program with folic acid.
Hirsch, Sandra; Sanchez, Hugo; Albala, Cecilia; de la Maza, María Pía; Barrera, Gladys; Leiva, Laura; Bunout, Daniel
2009-04-01
Folate depletion is associated with an increased risk of colorectal carcinogenesis. A temporal association between folic acid fortification of enriched cereal grains and an increase in the incidence of colorectal cancer in the USA and Canada has, however, been recently reported. To compare the rates of hospital discharges owing to colon cancer in Chile before and after the start of the mandatory flour fortification program with 220 microg of synthetic folic acid/100 g of wheat flour. Cancer and cardiovascular hospital discharge rates were compared using rate ratios between two study periods, 1992-1996, before folic acid fortification and 2001-2004, after the flour fortification with folic acid was established in the country. Standard errors of the log rate ratio to derive confidence intervals, and to test the null hypothesis of no difference, were calculated. The highest rate ratio between the two periods was for colon cancer in the group aged 45-64 years (rate ratio: 2.6, confidence interval: 99% 2.93-2.58) and in the 65-79 years (rate ratio: 2.9, confidence interval: 99% 3.25-2.86). Our data provide new evidence that a folate fortification program could be associated with an additional risk of colon cancer.
Hu, Peifeng; Wang, Serena; Lee, Jinkook
2017-09-01
Cardiovascular disease has become a major public health challenge in developing countries. The goal of this study is to compare socioeconomic status (SES) gradients of cardiovascular risk factors (CVRF) both within and between China and India. We used multivariable logistic regression models to examine the associations between SES and CVRF, using data from the China health and retirement longitudinal study and the longitudinal aging study in India. The results showed that, compared to illiteracy, the odds ratios of completing junior high school for high-risk waist circumference were 4.99 (95% confidence interval: 1.77-14.06) among Indian men, 3.42 (95% confidence interval: 1.66-7.05) among Indian women, but 0.74 (95% confidence interval: 0.59-0.92) among Chinese women. Similar patterns were observed between educational attainment and high-risk body mass index, and between education and hypertension, based on self-reported physician diagnosis and direct blood pressure measurements. SES is associated with CVRF in both China and India. However, this relationship showed opposite patterns across two countries, suggesting that this association is not fixed, but is subjective to underlying causal pathways, such as patterns of risky health behaviors and different social and health policies.
Towards the estimation of effect measures in studies using respondent-driven sampling.
Rotondi, Michael A
2014-06-01
Respondent-driven sampling (RDS) is an increasingly common sampling technique to recruit hidden populations. Statistical methods for RDS are not straightforward due to the correlation between individual outcomes and subject weighting; thus, analyses are typically limited to estimation of population proportions. This manuscript applies the method of variance estimates recovery (MOVER) to construct confidence intervals for effect measures such as risk difference (difference of proportions) or relative risk in studies using RDS. To illustrate the approach, MOVER is used to construct confidence intervals for differences in the prevalence of demographic characteristics between an RDS study and convenience study of injection drug users. MOVER is then applied to obtain a confidence interval for the relative risk between education levels and HIV seropositivity and current infection with syphilis, respectively. This approach provides a simple method to construct confidence intervals for effect measures in RDS studies. Since it only relies on a proportion and appropriate confidence limits, it can also be applied to previously published manuscripts.
Tully, Phillip J; Cosh, Suzanne M
2013-12-01
Generalized anxiety disorder prevalence and comorbidity with depression in coronary heart disease patients remain unquantified. Systematic searching of Medline, Embase, SCOPUS and PsycINFO databases revealed 1025 unique citations. Aggregate generalized anxiety disorder prevalence (12 studies, N = 3485) was 10.94 per cent (95% confidence interval: 7.8-13.99) and 13.52 per cent (95% confidence interval: 8.39-18.66) employing Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria (random effects). Lifetime generalized anxiety disorder prevalence was 25.80 per cent (95% confidence interval: 20.84-30.77). In seven studies, modest correlation was evident between generalized anxiety disorder and depression, Fisher's Z = .30 (95% confidence interval: .19-.42), suggesting that each psychiatric disorder is best conceptualized as contributing unique variance to coronary heart disease prognosis.
Maignen, François; Hauben, Manfred; Dogné, Jean-Michel
2017-01-01
Background: The lower bound of the 95% confidence interval of measures of disproportionality (Lower95CI) is widely used in signal detection. Masking is a statistical issue by which true signals of disproportionate reporting are hidden by the presence of other medicines. The primary objective of our study is to develop and validate a mathematical framework for assessing the masking effect of Lower95CI. Methods: We have developed our new algorithm based on the masking ratio (MR) developed for the measures of disproportionality. A MR for the Lower95CI (MRCI) is proposed. A simulation study to validate this algorithm was also conducted. Results: We have established the existence of a very close mathematical relation between MR and MRCI. For a given drug–event pair, the same product will be responsible for the highest masking effect with the measure of disproportionality and its Lower95CI. The extent of masking is likely to be very similar across the two methods. An important proportion of identical drug–event associations affected by the presence of an important masking effect is revealed by the unmasking exercise, whether the proportional reporting ratio (PRR) or its confidence interval are used. Conclusion: The detection of the masking effect of Lower95CI can be automated. The real benefits of this unmasking in terms of new true-positive signals (rate of true-positive/false-positive) or time gained by the revealing of signals using this method have not been fully assessed. These benefits should be demonstrated in the context of prospective studies. PMID:28845231
Immunohistochemical expression of ERG in the molecular epidemiology of fatal prostate cancer study.
Weinmann, Sheila; Van Den Eeden, Stephen K; Haque, Reina; Chen, Chuhe; Richert-Boe, Kathryn; Schwartzman, Jacob; Gao, Lina; Berry, Deborah L; Kallakury, Bhaskar V S; Alumkal, Joshi J
2013-09-01
Gene fusions between the ERG transcription factor and the androgen-regulated gene TMPRSS2 occur in a subset of prostate cancers and contribute to transformation of prostatic epithelial cells. Prior reports have used fluorescence in situ hybridization (FISH) or quantitative PCR (QPCR) to determine the presence of TMPRSS2-ERG fusions or ERG expression, respectively. Recently, several groups have reported on immunohistochemistry (IHC) to measure ERG expression, which is much more readily performed in clinical practice. However, the prior studies examining ERG expression by IHC had small sample sizes or they failed to clarify the association of ERG protein expression with important clinico-pathological features or prostate cancer-specific mortality. To address these deficits, we evaluated ERG expression by IHC in 208 radical prostatectomy samples from the Kaiser Permanente Molecular Epidemiology of Fatal Prostate Cancer (MEFPC) study, a case-control study of prostate cancer-specific mortality. Nuclear ERG expression was seen in neoplastic prostate epithelia in 49 of the samples (23.7%). ERG expression in tumor cells was associated with higher tumor stage (OR = 2.0, 95% confidence interval 1.0-4.0, P value = 0.04). ERG immunoreactivity was positively associated with prostate cancer-specific mortality, although the confidence interval was wide (OR = 1.9, 95% confidence interval 0.88-4.0, P value = 0.10). Our results demonstrate that ERG protein expression is readily quantifiable with an existing commercial antibody. Evaluating ERG protein expression may improve our ability to identify the subset of more aggressive, invasive prostate cancers. © 2013 Wiley Periodicals, Inc.
Tam, Teresa; Bilinski, Ewa; Lombard, Emily
2012-10-01
The purpose of the study is to evaluate the incidence of women with prior GBS genital colonization who have recolonization in subsequent pregnancies. This is a retrospective, cohort study of patients with a prior GBS genital colonization in pregnancy and a subsequent pregnancy with a recorded GBS culture result, from January 2000 through June 2007. Documentation of GBS status was through GBS culture performed between 35 to 37 weeks gestation. Exclusion criteria included pregnancies with unknown GBS status, patients with GBS bacteriuria, women with a previous neonate with GBS disease and GBS finding prior to 35 weeks. Data was analyzed using SPSS 15.0. The sample proportion of subjects with GBS genital colonization and its confidence interval were computed to estimate the incidence rate. Logistic regression was performed to assess potential determinants of GBS colonization. Regression coefficients, odds ratios and associated confidence intervals, and p-values were reported, with significant results reported. There were 371 pregnancies that met the test criteria. There were 151 subsequent pregnancies with GBS genital colonization and 220 without GBS recolonization. The incidence of GBS recolonization on patients with prior GBS genital colonization was 40.7% (95% confidence interval 35.7-45.69%). The incidence rate for the sample was significantly larger than 30% (p < .001), which is the estimated incidence rate for all pregnant women who are GBS carriers regardless of prior history. These results suggest that patients with a history of GBS are at a significantly higher risk of GBS recolonization in subsequent pregnancies.
Lymphovascular space invasion in robotic surgery for endometrial cancer.
Hopkins, Mark R; Richmond, Abby M; Cheng, Georgina; Davidson, Susan; Spillman, Monique A; Sheeder, Jeanelle; Post, Miriam D; Guntupalli, Saketh R
2014-01-01
Minimally invasive surgery has become a standard treatment for endometrial cancer and offers significant benefits over abdominal approaches. There are discrepant data regarding lymphovascular space invasion (LVSI) and positive peritoneal cytology with the use of a uterine manipulator, with previous small-scale studies demonstrating an increased incidence of these prognostically important events. We sought to determine if there was a higher incidence of LVSI in patients who underwent robot-assisted surgery for endometrial cancer. We performed a single-institution review of medical records for patients who underwent open abdominal or robot-assisted hysterectomy for endometrial cancer over a 24-month period. The following data were abstracted: age, tumor grade and stage, size, depth of invasion, LVSI, and peritoneal cytology. For patients with LVSI, slides were reviewed by 2 pathologists for confirmation of LVSI. Of 104 patients identified, LVSI was reported in 39 (37.5%) and positive peritoneal cytology in 6 (4.8%). Rates of peritoneal cytology were not significantly different between the 2 groups (odds ratio, 0.55; 95% confidence interval, 0.10-3.17; P=.50). LVSI was reported in significantly fewer robot-assisted hysterectomies than open procedures (odds ratio, 0.39; 95% confidence interval, 0.17-0.92; P=.03). In subgroup analyses restricted to early-stage disease (stage≤II), there was no significant difference in LVSI between open and robot-assisted hysterectomies (odds ratio, 0.64; 95% confidence interval, 0.22-1.85; P=.43). In this retrospective study, we found that use of a uterine manipulator in robot-assisted surgery did not increase the incidence of LVSI.
Marso, Steven P; Kennedy, Kevin F; House, John A; McGuire, Darren K
2010-04-01
We performed a meta-analysis of studies evaluating the effect of intensive glucose control on major adverse cardiovascular events in patients with type 2 diabetes from 1990 to 2009. A search of the published literature and the Cochran Central Register for Controlled Trials was performed using pre-specified inclusion criteria consisting of randomised controlled trials evaluating intensive glycaemic control and reporting the individual endpoints of all-cause mortality, non-fatal myocardial infarction, and non-fatal stroke. Incident rate ratios for these endpoints were calculated using standard meta-analytic techniques of pooled data from eligible trials. Six reports from four randomised trials including 27,544 patients met the pre-specified inclusion criteria. Mean follow-up was 5.4 years; haemoglobin A(1C) at study end was 6.6% vs. 7.4% in patients randomised to intensive compared with conventional glucose control. Intensive glucose control did not affect the incident rate ratio for all-cause mortality (1.01, 95% confidence interval 0.86-1.18, p=0.54) or stroke (1.02, 95% confidence interval 0.88-1.20, p=0.62). However, there was a statistically significant 14% reduction in non-fatal myocardial infarction in patients randomised to intensive glucose control (0.86, 95% confidence interval 0.77-0.97, p=0.015). Although intensification of glucose control did not affect mortality or non-fatal stroke, the risk for non-fatal myocardial infarction was significantly reduced in patients with type 2 diabetes.
Pandis, Nikolaos; Polychronopoulou, Argy; Madianos, Phoebus; Makou, Margarita; Eliades, Theodore
2011-06-01
The objective of this article was to record reporting characteristics related to study quality of research published in major specialty dental journals with the highest impact factor (Journal of Endodontics, Journal of Oral and Maxillofacial Surgery, American Journal of Orthodontics and Dentofacial Orthopedics; Pediatric Dentistry, Journal of Clinical Periodontology, and International Journal of Prosthetic Dentistry). The included articles were classified into the following 3 broad subject categories: (1) cross-sectional (snap-shot), (2) observational, and (3) interventional. Multinomial logistic regression was conducted for effect estimation using the journal as the response and randomization, sample calculation, confounding discussed, multivariate analysis, effect measurement, and confidence intervals as the explanatory variables. The results showed that cross-sectional studies were the dominant design (55%), whereas observational investigations accounted for 13%, and interventions/clinical trials for 32%. Reporting on quality characteristics was low for all variables: random allocation (15%), sample size calculation (7%), confounding issues/possible confounders (38%), effect measurements (16%), and multivariate analysis (21%). Eighty-four percent of the published articles reported a statistically significant main finding and only 13% presented confidence intervals. The Journal of Clinical Periodontology showed the highest probability of including quality characteristics in reporting results among all dental journals. Copyright © 2011 Elsevier Inc. All rights reserved.
Confidence intervals for a difference between lognormal means in cluster randomization trials.
Poirier, Julia; Zou, G Y; Koval, John
2017-04-01
Cluster randomization trials, in which intact social units are randomized to different interventions, have become popular in the last 25 years. Outcomes from these trials in many cases are positively skewed, following approximately lognormal distributions. When inference is focused on the difference between treatment arm arithmetic means, existent confidence interval procedures either make restricting assumptions or are complex to implement. We approach this problem by assuming log-transformed outcomes from each treatment arm follow a one-way random effects model. The treatment arm means are functions of multiple parameters for which separate confidence intervals are readily available, suggesting that the method of variance estimates recovery may be applied to obtain closed-form confidence intervals. A simulation study showed that this simple approach performs well in small sample sizes in terms of empirical coverage, relatively balanced tail errors, and interval widths as compared to existing methods. The methods are illustrated using data arising from a cluster randomization trial investigating a critical pathway for the treatment of community acquired pneumonia.
Adverse childhood experiences and disability in U.S. adults.
Schüssler-Fiorenza Rose, Sophia Miryam; Xie, Dawei; Stineman, Margaret
2014-08-01
To assess relationships between adverse childhood experiences and self-reported disabilities in adult life. Cross-sectional, random-digit-dialed, state-population-based survey (Behavioral Risk Factor Surveillance System). Fourteen states and the District of Columbia. Noninstitutionalized adults ages ≥18 years surveyed in 2009 and/or in 2010 (n = 81,184). The Behavioral Risk Factor Surveillance System Adverse Childhood Experience (ACE) Module asks about abuse (physical, sexual, emotional), family dysfunction (exposures to domestic violence, living with mentally ill, substance abusing, or incarcerated family member(s), and/or parental separation and/or divorce) that occurred before age 18 years. The ACE score sums affirmed ACE categories (range, 0-8). We controlled for demographic characteristics (age, race, education, income, and marital status) and self-reported physical health conditions (stroke, myocardial infarction, diabetes, coronary heart disease, asthma). Five states asked participants about mental health conditions (anxiety, depression). A subset analysis of participants in these states evaluated the effect of adjusting for these conditions. The primary outcome was disability (self-reported activity limitation and/or assistive device use). More than half of participants (57%) reported at least 1 adverse childhood experience category, and 23.2% reported disability. The odds ratio (95% confidence interval) of disability increased in a graded fashion from odds ratio 1.3 (95% confidence interval, 1.2-1.4) among those who experienced 1 adverse experience to odds ratio 5.8 (95% confidence interval, 4.6-7.5) among those with 7-8 adverse experiences compared with those with no such experiences when adjusting for demographic factors. The relationship between adverse experiences and disability remained strong after adjusting for physical and mental health conditions. There is a strong graded relationship between childhood exposure to abuse and household dysfunction and self-reported disability in adulthood, even after adjusting for potentially mediating health conditions. Greater clinician, researcher, and policymaker awareness of the impact of childhood adversity on disability is crucial to help those affected by childhood adversity lead more functional lives. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.
Kuhn, Andrew Warren; Solomon, Gary S
2014-01-01
Computerized neuropsychological testing batteries have provided a time-efficient and cost-efficient way to assess and manage the neurocognitive aspects of patients with sport-related concussion. These tests are straightforward and mostly self-guided, reducing the degree of clinician involvement required by traditional clinical neuropsychological paper-and-pencil tests. To determine if self-reported supervision status affected computerized neurocognitive baseline test performance in high school athletes. Retrospective cohort study. Supervised testing took place in high school computer libraries or sports medicine clinics. Unsupervised testing took place at the participant's home or another location with computer access. From 2007 to 2012, high school athletes across middle Tennessee (n = 3771) completed computerized neurocognitive baseline testing (Immediate Post-Concussion Assessment and Cognitive Testing [ImPACT]). They reported taking the test either supervised by a sports medicine professional or unsupervised. These athletes (n = 2140) were subjected to inclusion and exclusion criteria and then matched based on age, sex, and number of prior concussions. We extracted demographic and performance-based data from each de-identified baseline testing record. Paired t tests were performed between the self-reported supervised and unsupervised groups, comparing the following ImPACT baseline composite scores: verbal memory, visual memory, visual motor (processing) speed, reaction time, impulse control, and total symptom score. For differences that reached P < .05, the Cohen d was calculated to measure the effect size. Lastly, a χ(2) analysis was conducted to compare the rate of invalid baseline testing between the groups. All statistical tests were performed at the 95% confidence interval level. Self-reported supervised athletes demonstrated better visual motor (processing) speed (P = .004; 95% confidence interval [0.28, 1.52]; d = 0.12) and faster reaction time (P < .001; 95% confidence interval [-0.026, -0.014]; d = 0.21) composite scores than self-reported unsupervised athletes. Speed-based tasks were most affected by self-reported supervision status, although the effect sizes were relatively small. These data lend credence to the hypothesis that supervision status may be a factor in the evaluation of ImPACT baseline test scores.
The Distribution of the Product Explains Normal Theory Mediation Confidence Interval Estimation.
Kisbu-Sakarya, Yasemin; MacKinnon, David P; Miočević, Milica
2014-05-01
The distribution of the product has several useful applications. One of these applications is its use to form confidence intervals for the indirect effect as the product of 2 regression coefficients. The purpose of this article is to investigate how the moments of the distribution of the product explain normal theory mediation confidence interval coverage and imbalance. Values of the critical ratio for each random variable are used to demonstrate how the moments of the distribution of the product change across values of the critical ratio observed in research studies. Results of the simulation study showed that as skewness in absolute value increases, coverage decreases. And as skewness in absolute value and kurtosis increases, imbalance increases. The difference between testing the significance of the indirect effect using the normal theory versus the asymmetric distribution of the product is further illustrated with a real data example. This article is the first study to show the direct link between the distribution of the product and indirect effect confidence intervals and clarifies the results of previous simulation studies by showing why normal theory confidence intervals for indirect effects are often less accurate than those obtained from the asymmetric distribution of the product or from resampling methods.
Ishikawa, Joji; Ishikawa, Shizukiyo; Kario, Kazuomi
2015-03-01
We attempted to evaluate whether subjects who exhibit prolonged corrected QT (QTc) interval (≥440 ms in men and ≥460 ms in women) on ECG, with and without ECG-diagnosed left ventricular hypertrophy (ECG-LVH; Cornell product, ≥244 mV×ms), are at increased risk of stroke. Among the 10 643 subjects, there were a total of 375 stroke events during the follow-up period (128.7±28.1 months; 114 142 person-years). The subjects with prolonged QTc interval (hazard ratio, 2.13; 95% confidence interval, 1.22-3.73) had an increased risk of stroke even after adjustment for ECG-LVH (hazard ratio, 1.71; 95% confidence interval, 1.22-2.40). When we stratified the subjects into those with neither a prolonged QTc interval nor ECG-LVH, those with a prolonged QTc interval but without ECG-LVH, and those with ECG-LVH, multivariate-adjusted Cox proportional hazards analysis demonstrated that the subjects with prolonged QTc intervals but not ECG-LVH (1.2% of all subjects; incidence, 10.7%; hazard ratio, 2.70, 95% confidence interval, 1.48-4.94) and those with ECG-LVH (incidence, 7.9%; hazard ratio, 1.83; 95% confidence interval, 1.31-2.57) had an increased risk of stroke events, compared with those with neither a prolonged QTc interval nor ECG-LVH. In conclusion, prolonged QTc interval was associated with stroke risk even among patients without ECG-LVH in the general population. © 2014 American Heart Association, Inc.
A Call for Statistical Reform in EAQ
ERIC Educational Resources Information Center
Byrd, Jimmy K.
2007-01-01
Purpose: The purpose of this study was to review research published by Educational Administration Quarterly (EAQ) during the past 10 years to determine if confidence intervals and effect sizes were being reported as recommended by the American Psychological Association (APA) Publication Manual. Research Design: The author examined 49 volumes of…
Donald B.K. English
2000-01-01
In this paper I use bootstrap procedures to develop confidence intervals for estimates of total industrial output generated per thousand tourist visits. Mean expenditures from replicated visitor expenditure data included weights to correct for response bias. Impacts were estimated with IMPLAN. Ninety percent interval endpoints were 6 to 16 percent above or below the...
Pellar, T G; Ward, P J; Tuckerman, J F; Henderson, A R
1993-06-01
Test turnaround times are often monitored on a monthly basis. However, such an interval usually means that not all causes for delay in test reporting can be unequivocally identified for institution of remedial action. We have devised a daily chart--the freckle plot--that graphically displays the test turnaround times by laboratory receipt time. Different symbols are used to designate specimens reported within the test's turnaround time limit, those within 10 min beyond that limit, and those well outside the limit. These categories are adjustable to suit different limits of stringency. Freckle plots are produced on a daily basis and can be used to track down causes for test delays. Using the 1-h turnaround time "stat" potassium test as a model, we found 16 causes for test delay, of which 9 were potentially remediable. By applying these remedies, we were able to increase test compliance, in the day shift, from 91.5% (95% confidence interval 88.8%-93.7%) to 97.6% (95% confidence interval 96.4-98.55%), which is significant at P < 10(-7). This daily plot is a useful quality assurance tool, supplementing the more conventional tests used to ensure laboratory quality improvement.
Brand, Andrew; Bradley, Michael T
2016-02-01
Confidence interval ( CI) widths were calculated for reported Cohen's d standardized effect sizes and examined in two automated surveys of published psychological literature. The first survey reviewed 1,902 articles from Psychological Science. The second survey reviewed a total of 5,169 articles from across the following four APA journals: Journal of Abnormal Psychology, Journal of Applied Psychology, Journal of Experimental Psychology: Human Perception and Performance, and Developmental Psychology. The median CI width for d was greater than 1 in both surveys. Hence, CI widths were, as Cohen (1994) speculated, embarrassingly large. Additional exploratory analyses revealed that CI widths varied across psychological research areas and that CI widths were not discernably decreasing over time. The theoretical implications of these findings are discussed along with ways of reducing the CI widths and thus improving precision of effect size estimation.
Does blood transfusion affect intermediate survival after coronary artery bypass surgery?
Mikkola, R; Heikkinen, J; Lahtinen, J; Paone, R; Juvonen, T; Biancari, F
2013-01-01
The aim of this study was to investigate the impact of transfusion of blood products on intermediate outcome after coronary artery bypass surgery. Complete data on perioperative blood transfusion in patients undergoing coronary artery bypass surgery were available from 2001 patients who were operated at our institution. Transfusion of any blood product (relative risk = 1.678, 95% confidence interval = 1.087-2.590) was an independent predictor of all-cause mortality. The additive effect of each blood product on all-cause mortality (relative risk = 1.401, 95% confidence interval = 1.203-1.630) and cardiac mortality (relative risk = 1.553, 95% confidence interval = 1.273-1.895) was evident when the sum of each blood product was included in the regression models. However, when single blood products were included in the regression model, transfusion of fresh frozen plasma/Octaplas® was the only blood product associated with increased risk of all-cause mortality (relative risk = 1.692, 95% confidence interval = 1.222-2.344) and cardiac mortality (relative risk = 2.125, 95% confidence interval = 1.414-3.194). The effect of blood product transfusion was particularly evident during the first three postoperative months. Since follow-up was truncated at 3 months, transfusion of any blood product was a significant predictor of all-cause mortality (relative risk = 2.998, 95% confidence interval = 1.053-0.537). Analysis of patients who survived or had at least 3 months of potential follow-up showed that transfusion of any blood product was not associated with a significantly increased risk of intermediate all-cause mortality (relative risk = 1.430, 95% confidence interval = 0.880-2.323). Transfusion of any blood product is associated with a significant risk of all-cause and cardiac mortality after coronary artery bypass surgery. Such a risk seems to be limited to the early postoperative period and diminishes later on. Among blood products, perioperative use of fresh frozen plasma or Octaplas seems to be the main determinant of mortality.
Besson, Florent L; Henry, Théophraste; Meyer, Céline; Chevance, Virgile; Roblot, Victoire; Blanchet, Elise; Arnould, Victor; Grimon, Gilles; Chekroun, Malika; Mabille, Laurence; Parent, Florence; Seferian, Andrei; Bulifon, Sophie; Montani, David; Humbert, Marc; Chaumet-Riffaud, Philippe; Lebon, Vincent; Durand, Emmanuel
2018-04-03
Purpose To assess the performance of the ITK-SNAP software for fluorodeoxyglucose (FDG) positron emission tomography (PET) segmentation of complex-shaped lung tumors compared with an optimized, expert-based manual reference standard. Materials and Methods Seventy-six FDG PET images of thoracic lesions were retrospectively segmented by using ITK-SNAP software. Each tumor was manually segmented by six raters to generate an optimized reference standard by using the simultaneous truth and performance level estimate algorithm. Four raters segmented 76 FDG PET images of lung tumors twice by using ITK-SNAP active contour algorithm. Accuracy of ITK-SNAP procedure was assessed by using Dice coefficient and Hausdorff metric. Interrater and intrarater reliability were estimated by using intraclass correlation coefficients of output volumes. Finally, the ITK-SNAP procedure was compared with currently recommended PET tumor delineation methods on the basis of thresholding at 41% volume of interest (VOI; VOI 41 ) and 50% VOI (VOI 50 ) of the tumor's maximal metabolism intensity. Results Accuracy estimates for the ITK-SNAP procedure indicated a Dice coefficient of 0.83 (95% confidence interval: 0.77, 0.89) and a Hausdorff distance of 12.6 mm (95% confidence interval: 9.82, 15.32). Interrater reliability was an intraclass correlation coefficient of 0.94 (95% confidence interval: 0.91, 0.96). The intrarater reliabilities were intraclass correlation coefficients above 0.97. Finally, VOI 41 and VOI 50 accuracy metrics were as follows: Dice coefficient, 0.48 (95% confidence interval: 0.44, 0.51) and 0.34 (95% confidence interval: 0.30, 0.38), respectively, and Hausdorff distance, 25.6 mm (95% confidence interval: 21.7, 31.4) and 31.3 mm (95% confidence interval: 26.8, 38.4), respectively. Conclusion ITK-SNAP is accurate and reliable for active-contour-based segmentation of heterogeneous thoracic PET tumors. ITK-SNAP surpassed the recommended PET methods compared with ground truth manual segmentation. © RSNA, 2018.
Quantitative imaging biomarkers: Effect of sample size and bias on confidence interval coverage.
Obuchowski, Nancy A; Bullen, Jennifer
2017-01-01
Introduction Quantitative imaging biomarkers (QIBs) are being increasingly used in medical practice and clinical trials. An essential first step in the adoption of a quantitative imaging biomarker is the characterization of its technical performance, i.e. precision and bias, through one or more performance studies. Then, given the technical performance, a confidence interval for a new patient's true biomarker value can be constructed. Estimating bias and precision can be problematic because rarely are both estimated in the same study, precision studies are usually quite small, and bias cannot be measured when there is no reference standard. Methods A Monte Carlo simulation study was conducted to assess factors affecting nominal coverage of confidence intervals for a new patient's quantitative imaging biomarker measurement and for change in the quantitative imaging biomarker over time. Factors considered include sample size for estimating bias and precision, effect of fixed and non-proportional bias, clustered data, and absence of a reference standard. Results Technical performance studies of a quantitative imaging biomarker should include at least 35 test-retest subjects to estimate precision and 65 cases to estimate bias. Confidence intervals for a new patient's quantitative imaging biomarker measurement constructed under the no-bias assumption provide nominal coverage as long as the fixed bias is <12%. For confidence intervals of the true change over time, linearity must hold and the slope of the regression of the measurements vs. true values should be between 0.95 and 1.05. The regression slope can be assessed adequately as long as fixed multiples of the measurand can be generated. Even small non-proportional bias greatly reduces confidence interval coverage. Multiple lesions in the same subject can be treated as independent when estimating precision. Conclusion Technical performance studies of quantitative imaging biomarkers require moderate sample sizes in order to provide robust estimates of bias and precision for constructing confidence intervals for new patients. Assumptions of linearity and non-proportional bias should be assessed thoroughly.
Association between GFR Estimated by Multiple Methods at Dialysis Commencement and Patient Survival
Wong, Muh Geot; Pollock, Carol A.; Cooper, Bruce A.; Branley, Pauline; Collins, John F.; Craig, Jonathan C.; Kesselhut, Joan; Luxton, Grant; Pilmore, Andrew; Harris, David C.
2014-01-01
Summary Background and objectives The Initiating Dialysis Early and Late study showed that planned early or late initiation of dialysis, based on the Cockcroft and Gault estimation of GFR, was associated with identical clinical outcomes. This study examined the association of all-cause mortality with estimated GFR at dialysis commencement, which was determined using multiple formulas. Design, setting, participants, & measurements Initiating Dialysis Early and Late trial participants were stratified into tertiles according to the estimated GFR measured by Cockcroft and Gault, Modification of Diet in Renal Disease, or Chronic Kidney Disease-Epidemiology Collaboration formula at dialysis commencement. Patient survival was determined using multivariable Cox proportional hazards model regression. Results Only Initiating Dialysis Early and Late trial participants who commenced on dialysis were included in this study (n=768). A total of 275 patients died during the study. After adjustment for age, sex, racial origin, body mass index, diabetes, and cardiovascular disease, no significant differences in survival were observed between estimated GFR tertiles determined by Cockcroft and Gault (lowest tertile adjusted hazard ratio, 1.11; 95% confidence interval, 0.82 to 1.49; middle tertile hazard ratio, 1.29; 95% confidence interval, 0.96 to 1.74; highest tertile reference), Modification of Diet in Renal Disease (lowest tertile hazard ratio, 0.88; 95% confidence interval, 0.63 to 1.24; middle tertile hazard ratio, 1.20; 95% confidence interval, 0.90 to 1.61; highest tertile reference), and Chronic Kidney Disease-Epidemiology Collaboration equations (lowest tertile hazard ratio, 0.93; 95% confidence interval, 0.67 to 1.27; middle tertile hazard ratio, 1.15; 95% confidence interval, 0.86 to 1.54; highest tertile reference). Conclusion Estimated GFR at dialysis commencement was not significantly associated with patient survival, regardless of the formula used. However, a clinically important association cannot be excluded, because observed confidence intervals were wide. PMID:24178976
VizieR Online Data Catalog: Fermi/GBM GRB time-resolved spectral catalog (Yu+, 2016)
NASA Astrophysics Data System (ADS)
Yu, H.-F.; Preece, R. D.; Greiner, J.; Bhat, P. N.; Bissaldi, E.; Briggs, M. S.; Cleveland, W. H.; Connaughton, V.; Goldstein, A.; von Kienlin; A.; Kouveliotou, C.; Mailyan, B.; Meegan, C. A.; Paciesas, W. S.; Rau, A.; Roberts, O. J.; Veres, P.; Wilson-Hodge, C.; Zhang, B.-B.; van Eerten, H. J.
2016-01-01
Time-resolved spectral analysis results of BEST models: for each spectrum GRB name using the Fermi GBM trigger designation, spectrum number within individual burst, start time Tstart and end time Tstop for the time bin, BEST model, best-fit parameters of the BEST model, value of CSTAT per degrees of freedom, 10keV-1MeV photon and energy flux are given. Ep evolutionary trends: for each burst GRB name, number of spectra with Ep, Spearman's Rank Correlation Coefficients between Ep_ and photon flux and 90%, 95%, and 99% confidence intervals, Spearman's Rank Correlation Coefficients between Ep and energy flux and 90%, 95%, and 99% confidence intervals, Spearman's Rank Correlation Coefficient between Ep and time and 90%, 95%, and 99% confidence intervals, trends as determined by computer for 90%, 95%, and 99% confidence intervals, trends as determined by human eyes are given. (2 data files).
Intervals for posttest probabilities: a comparison of 5 methods.
Mossman, D; Berger, J O
2001-01-01
Several medical articles discuss methods of constructing confidence intervals for single proportions and the likelihood ratio, but scant attention has been given to the systematic study of intervals for the posterior odds, or the positive predictive value, of a test. The authors describe 5 methods of constructing confidence intervals for posttest probabilities when estimates of sensitivity, specificity, and the pretest probability of a disorder are derived from empirical data. They then evaluate each method to determine how well the intervals' coverage properties correspond to their nominal value. When the estimates of pretest probabilities, sensitivity, and specificity are derived from more than 80 subjects and are not close to 0 or 1, all methods generate intervals with appropriate coverage properties. When these conditions are not met, however, the best-performing method is an objective Bayesian approach implemented by a simple simulation using a spreadsheet. Physicians and investigators can generate accurate confidence intervals for posttest probabilities in small-sample situations using the objective Bayesian approach.
Luke, Barbara
2017-09-01
Infertility, defined as the inability to conceive within 1 year of unprotected intercourse, affects an estimated 80 million individuals worldwide, or 10-15% of couples of reproductive age. Assisted reproductive technology includes all infertility treatments to achieve conception; in vitro fertilization is the process by which an oocyte is fertilized by semen outside the body; non-in vitro fertilization assisted reproductive technology treatments include ovulation induction, artificial insemination, and intrauterine insemination. Use of assisted reproductive technology has risen steadily in the United States during the past 2 decades due to several reasons, including childbearing at older maternal ages and increasing insurance coverage. The number of in vitro fertilization cycles in the United States has nearly doubled from 2000 through 2013 and currently 1.7% of all live births in the United States are the result of this technology. Since the birth of the first child from in vitro fertilization >35 years ago, >5 million babies have been born from in vitro fertilization, half within the past 6 years. It is estimated that 1% of singletons, 19% of twins, and 25% of triplet or higher multiples are due to in vitro fertilization, and 4%, 21%, and 52%, respectively, are due to non-in vitro fertilization assisted reproductive technology. Higher plurality at birth results in a >10-fold increase in the risks for prematurity and low birthweight in twins vs singletons (adjusted odds ratio, 11.84; 95% confidence interval, 10.56-13.27 and adjusted odds ratio, 10.68; 95% confidence interval, 9.45-12.08, respectively). The use of donor oocytes is associated with increased risks for pregnancy-induced hypertension (adjusted odds ratio, 1.43; 95% confidence interval, 1.14-1.78) and prematurity (adjusted odds ratio, 1.43; 95% confidence interval, 1.11-1.83). The use of thawed embryos is associated with higher risks for pregnancy-induced hypertension (adjusted odds ratio, 1.30; 95% confidence interval, 1.08-1.57) and large-for-gestation birthweight (adjusted odds ratio, 1.74; 95% confidence interval, 1.45-2.08). Among singletons, in vitro fertilization is associated with increased risk of severe maternal morbidity compared with fertile deliveries (vaginal: adjusted odds ratio, 2.27; 95% confidence interval, 1.78-2.88; cesarean: adjusted odds ratio, 1.67; 95% confidence interval, 1.40-1.98, respectively) and subfertile deliveries (vaginal: adjusted odds ratio, 1.97; 95% confidence interval, 1.30-3.00; cesarean: adjusted odds ratio, 1.75; 95% confidence interval, 1.30-2.35, respectively). Among twins, cesarean in vitro fertilization deliveries have significantly greater severe maternal morbidity compared to cesarean fertile deliveries (adjusted odds ratio, 1.48; 95% confidence interval, 1.14-1.93). Subfertility, with or without in vitro fertilization or non-in vitro fertilization infertility treatments to achieve a pregnancy, is associated with increased risks of adverse maternal and perinatal outcomes. The major risk from in vitro fertilization treatments of multiple births (and the associated excess of perinatal morbidity) has been reduced over time, with fewer and better-quality embryos being transferred. Copyright © 2017. Published by Elsevier Inc.
Cust, Anne E; Armstrong, Bruce K; Smith, Ben J; Chau, Josephine; van der Ploeg, Hidde P; Bauman, Adrian
2009-05-01
Self-reported confidence ratings have been used in other research disciplines as a tool to assess data quality, and may be useful in epidemiologic studies. We examined whether self-reported confidence in recall of physical activity was a predictor of the validity and retest reliability of physical activity measures from the European Prospective Investigation into Cancer and Nutrition (EPIC) past-year questionnaire and the International Physical Activity Questionnaire (IPAQ) last-7-day questionnaire.During 2005-2006 in Sydney, Australia, 97 men and 80 women completed both questionnaires at baseline and at 10 months and wore an accelerometer as an objective comparison measure for three 7-day periods during the same timeframe. Participants rated their confidence in recalling physical activity for each question using a 5-point scale and were dichotomized at the median confidence value. Participants in the high-confidence group had higher validity and repeatability coefficients than those in the low-confidence group for most comparisons. The differences were most apparent for validity of IPAQ moderate activity: Spearman correlation rho = 0.34 (95% confidence interval [CI] = 0.08 to 0.55) and 0.01 (-0.17 to 0.20) for high- and low-confidence groups, respectively; and repeatability of EPIC household activity: rho = 0.81 (0.72 to 0.87) and 0.63 (0.48 to 0.74), respectively, and IPAQ vigorous activity: rho = 0.58 (0.43 to 0.70) and 0.29 (0.07 to 0.49), respectively. Women were less likely than men to report high recall confidence of past-year activity (adjusted odds ratio = 0.38; 0.18 to 0.80). Confidence ratings could be useful as indicators of recall accuracy (ie, validity and repeatability) of physical activity measures, and possibly for detecting differential measurement error and identifying questionnaire items that require improvement.
Biomarker validation of self-reported sex among middle-aged female sex workers in China.
Guida, Jennifer; Fukunaga, Ami; Liu, Hongjie
2017-03-01
The objective of this study was to examine information bias arising from self-reported sexual activity and its association with syphilitic infections among female sex workers (FSWs) aged 35 years and older in China. A questionnaire was administered to 1245 middle-aged FSWs. Respondents self-reported sexual intercourse in the past 48 hours. The prostate-specific antigen test was used to verify self-reported sexual activity. FSWs were considered discordant if they indicated no sexual intercourse in the past 48 hours on the questionnaire and had a positive prostate-specific antigen test. Logistic regression was used to assess the associations between discordance and syphilis. Three hundred twenty FSWs self-reported no engagement in sexual intercourse in the past 48 hours. One-fourth of respondents (25%) were discordant. Twenty-two percent and 35.8% of discordant FSWs tested positive for active and prevalent syphilis, respectively. After adjusting for confounders, discordant FSWs had 3.8 times the odds of active syphilis (95% confidence interval: 1.52-9.30) and 2.6 times the odds of prevalent syphilis (95% confidence interval: 1.37-5.02), compared with concordant FSWs. FSWs who had active or prevalent syphilis were more likely to be discordant. Data collected via self-reported questionnaire may not be a valid tool to assess sexual behavior. Copyright © 2017 Elsevier Inc. All rights reserved.
Saps, M; Lavigne, J V
2015-06-01
The Food and Drug Administration (FDA) recommended ≥30% decrease on patient-reported outcomes for pain be considered clinically significant in clinical trials for adults with irritable bowel syndrome. This percent change approach may not be appropriate for children. We compared three alternate approaches to determining clinically significant reductions in pain among children. 80 children with functional abdominal pain participated in a study of the efficacy of amitriptyline. Endpoints included patient-reported estimates of feeling better, and pain Visual Analog Scale (VAS). The minimum clinically important difference in pain report was calculated as (i) mean change in VAS score for children reporting being 'better'; (ii) percent changes in pain (≥30% and ≥50%) on the VAS; and (iii) statistically reliable changes on the VAS for 68% and 95% confidence intervals. There was poor agreement between the three approaches. 43.6% of the children who met the FDA ≥30% criterion for clinically significant change did not achieve a reliable level of improvement (95% confidence interval). Children's self-reported ratings of being better may not be statistically reliable. A combined approach in which children must report improvement as better and achieve a statistically significant change may be more appropriate for outcomes in clinical trials. © 2015 John Wiley & Sons Ltd.
Mohd Shariff, Noorsuzana; Shah, Shamsul Azhar; Kamaludin, Fadzilah
2016-03-01
The number of multidrug-resistant tuberculosis patients is increasing each year in many countries all around the globe. Malaysia has no exception in facing this burdensome health problem. We aimed to investigate the factors that contribute to the occurrence of multidrug-resistant tuberculosis among Malaysian tuberculosis patients. An unmatched case-control study was conducted among tuberculosis patients who received antituberculosis treatments from April 2013 until April 2014. Cases are those diagnosed as pulmonary tuberculosis patients clinically, radiologically, and/or bacteriologically, and who were confirmed to be resistant to both isoniazid and rifampicin through drug-sensitivity testing. On the other hand, pulmonary tuberculosis patients who were sensitive to all first-line antituberculosis drugs and were treated during the same time period served as controls. A total of 150 tuberculosis patients were studied, of which the susceptible cases were 120. Factors found to be significantly associated with the occurrence of multidrug-resistant tuberculosis are being Indian or Chinese (odds ratio 3.17, 95% confidence interval 1.04-9.68; and odds ratio 6.23, 95% confidence interval 2.24-17.35, respectively), unmarried (odds ratio 2.58, 95% confidence interval 1.09-6.09), living in suburban areas (odds ratio 2.58, 95% confidence interval 1.08-6.19), are noncompliant (odds ratio 4.50, 95% confidence interval 1.71-11.82), were treated previously (odds ratio 8.91, 95% confidence interval 3.66-21.67), and showed positive sputum smears at the 2nd (odds ratio 7.00, 95% confidence interval 2.46-19.89) and 6th months of treatment (odds ratio 17.96, 95% confidence interval 3.51-91.99). Living in suburban areas, positive sputum smears in the 2nd month of treatment, and was treated previously are factors that independently contribute to the occurrence of multidrug-resistant tuberculosis. Those with positive smears in the second month of treatment, have a history of previous treatment, and live in suburban areas are found to have a higher probability of becoming multidrug resistant. The results presented here may facilitate improvements in the screening and detection process of drug-resistant patients in Malaysia in the future. Copyright © 2015 Asian-African Society for Mycobacteriology. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Lilly, P.; Yanai, R. D.; Buckley, H. L.; Case, B. S.; Woollons, R. C.; Holdaway, R. J.; Johnson, J.
2016-12-01
Calculations of forest biomass and elemental content require many measurements and models, each contributing uncertainty to the final estimates. While sampling error is commonly reported, based on replicate plots, error due to uncertainty in the regression used to estimate biomass from tree diameter is usually not quantified. Some published estimates of uncertainty due to the regression models have used the uncertainty in the prediction of individuals, ignoring uncertainty in the mean, while others have propagated uncertainty in the mean while ignoring individual variation. Using the simple case of the calcium concentration of sugar maple leaves, we compare the variation among individuals (the standard deviation) to the uncertainty in the mean (the standard error) and illustrate the declining importance in the prediction of individual concentrations as the number of individuals increases. For allometric models, the analogous statistics are the prediction interval (or the residual variation in the model fit) and the confidence interval (describing the uncertainty in the best fit model). The effect of propagating these two sources of error is illustrated using the mass of sugar maple foliage. The uncertainty in individual tree predictions was large for plots with few trees; for plots with 30 trees or more, the uncertainty in individuals was less important than the uncertainty in the mean. Authors of previously published analyses have reanalyzed their data to show the magnitude of these two sources of uncertainty in scales ranging from experimental plots to entire countries. The most correct analysis will take both sources of uncertainty into account, but for practical purposes, country-level reports of uncertainty in carbon stocks, as required by the IPCC, can ignore the uncertainty in individuals. Ignoring the uncertainty in the mean will lead to exaggerated estimates of confidence in estimates of forest biomass and carbon and nutrient contents.
Stapled versus handsewn methods for colorectal anastomosis surgery.
Lustosa, S A; Matos, D; Atallah, A N; Castro, A A
2001-01-01
Randomized controlled trials comparing stapled with handsewn colorectal anastomosis have not shown either technique to be superior, perhaps because individual studies lacked statistical power. A systematic review, with pooled analysis of results, might provide a more definitive answer. To compare the safety and effectiveness of stapled and handsewn colorectal anastomosis. The following primary hypothesis was tested: the stapled technique is more effective because it decreases the level of complications. The RCT register of the Cochrane Review Group was searched for any trial or reference to a relevant trial (published, in-press, or in progress). All publications were sought through computerised searches of EMBASE, LILACS, MEDLINE, the Cochrane Controlled Clinical Trials Database, and through letters to industrial companies and authors. There were no limits upon language, date, or other criteria. All randomized clinical trials (RCTs) in which stapled and handsewn colorectal anastomosis were compared. Adult patients submitted electively to colorectal anastomosis. Endoluminal circular stapler and handsewn colorectal anastomosis. a) Mortality b) Overall Anastomotic Dehiscence c) Clinical Anastomotic Dehiscence d) Radiological Anastomotic Dehiscence e) Stricture f) Anastomotic Haemorrhage g) Reoperation h) Wound Infection i) Anastomosis Duration j) Hospital Stay. Data were independently extracted by the two reviewers (SASL, DM) and cross-checked. The methodological quality of each trial was assessed by the same two reviewers. Details of the randomization (generation and concealment), blinding, whether an intention-to-treat analysis was done, and the number of patients lost to follow-up were recorded. The results of each RCT were summarised on an intention-to-treat basis in 2 x 2 tables for each outcome. External validity was defined by characteristics of the participants, the interventions and the outcomes. The RCTs were stratified according to the level of colorectal anastomosis. The Risk Difference method (random effects model) and NNT for dichotomous outcomes measures and weighted mean difference for continuous outcomes measures, with the corresponding 95% confidence interval, were presented in this review. Statistical heterogeneity was evaluated by using funnel plot and chi-square testing. Of the 1233 patients enrolled ( in 9 trials), 622 were treated with stapled, and 611 with manual, suture. The following main results were obtained: a) Mortality: result based on 901 patients; Risk Difference - 0.6% Confidence Interval -2.8% to +1.6%. b) Overall Dehiscence: result based on 1233 patients; Risk Difference 0.2%, 95% Confidence Interval -5.0% to +5.3%. c) Clinical Anastomotic Dehiscence : result based on 1233 patients; Risk Difference -1.4%, 95% Confidence Interval -5.2 to +2.3%. d) Radiological Anastomotic Dehiscence : result based on 825 patients; Risk Difference 1.2%, 95% Confidence Interval -4.8% to +7.3%. e) Stricture: result based on 1042 patients; Risk Difference 4.6%, 95% Confidence Interval 1.2% to 8.1%. Number needed to treat 17, 95% confidence interval 12 to 31. f) Anastomotic Hemorrhage: result based on 662 patients; Risk Difference 2.7%, 95% Confidence Interval - 0.1% to +5.5%. g) Reoperation: result based on 544 patients; Risk Difference 3.9%, 95% Confidence Interval 0.3% to 7.4%. h) Wound Infection: result based on 567 patients; Risk Difference 1.0%, 95% Confidence Interval -2.2% to +4.3%. i) Anastomosis duration: result based on one study (159 patients); Weighted Mean Difference -7.6 minutes, 95% Confidence Interval -12.9 to -2.2 minutes. j) Hospital Stay: result based on one study (159 patients), Weighted Mean Difference 2.0 days, 95% Confidence Interval -3.27 to +7.2 days. The evidence found was insufficient to demonstrate any superiority of stapled over handsewn techniques in colorectal anastomosis, regardless of the level of anastomosis.
Age and fecundability in a North American preconception cohort study.
Wesselink, Amelia K; Rothman, Kenneth J; Hatch, Elizabeth E; Mikkelsen, Ellen M; Sørensen, Henrik T; Wise, Lauren A
2017-12-01
There is a well-documented decline in fertility treatment success with increasing female age; however, there are few preconception cohort studies that have examined female age and natural fertility. In addition, data on male age and fertility are inconsistent. Given the increasing number of couples who are attempting conception at older ages, a more detailed characterization of age-related fecundability in the general population is of great clinical utility. The purpose of this study was to examine the association between female and male age with fecundability. We conducted a web-based preconception cohort study of pregnancy planners from the United States and Canada. Participants were enrolled between June 2013 and July 2017. Eligible participants were 21-45 years old (female) or ≥21 years old (male) and had not been using fertility treatments. Couples were followed until pregnancy or for up to 12 menstrual cycles. We analyzed data from 2962 couples who had been trying to conceive for ≤3 cycles at study entry and reported no history of infertility. We used life-table methods to estimate the unadjusted cumulative pregnancy proportion at 6 and 12 cycles by female and male age. We used proportional probabilities regression models to estimate fecundability ratios, the per-cycle probability of conception for each age category relative to the referent (21-24 years old), and 95% confidence intervals. Among female patients, the unadjusted cumulative pregnancy proportion at 6 cycles of attempt time ranged from 62.0% (age 28-30 years) to 27.6% (age 40-45 years); the cumulative pregnancy proportion at 12 cycles of attempt time ranged from 79.3% (age 25-27 years old) to 55.5% (age 40-45 years old). Similar patterns were observed among male patients, although differences between age groups were smaller. After adjusting for potential confounders, we observed a nearly monotonic decline in fecundability with increasing female age, with the exception of 28-33 years, at which point fecundability was relatively stable. Fecundability ratios were 0.91 (95% confidence interval, 0.74-1.11) for ages 25-27, 0.88 (95% confidence interval, 0.72-1.08) for ages 28-30, 0.87 (95% confidence interval, 0.70-1.08) for ages 31-33, 0.82 (95% confidence interval, 0.64-1.05) for ages 34-36, 0.60 (95% confidence interval, 0.44-0.81) for ages 37-39, and 0.40 (95% confidence interval, 0.22-0.73) for ages 40-45, compared with the reference group (age, 21-24 years). The association was stronger among nulligravid women. Male age was not associated appreciably with fecundability after adjustment for female age, although the number of men >45 years old was small (n=37). In this preconception cohort study of North American pregnancy planners, increasing female age was associated with an approximately linear decline in fecundability. Although we found little association between male age and fecundability, the small number of men in our study >45 years old limited our ability to draw conclusions on fecundability in older men. Copyright © 2017 Elsevier Inc. All rights reserved.
Cuttance, E L; Mason, W A; McDermott, J; Laven, R A; McDougall, S; Phyn, C V C
2017-10-01
The aims of this study were to (1) estimate the perinatal (birth to 24 h) and postnatal (∼24 h to the mean weaning age of 13 wk) mortality risk in pasture-based dairy calves until weaning, and (2) identify associated risk factors in the 2015 calving season. A prospective survey of 32 seasonal calving dairy farms was undertaken. Farmers recorded (daily) the number and sex of the calves alive or dead in the paddocks where cows calved. All daily animal movements in and out of the calf rearing facilities, including death and euthanasia, and the identification of the animals (if applicable) were recorded, and a survey of the farm management practices was undertaken. Individual and farm-level risk factors for perinatal mortality were modeled separately using generalized logistic mixed models with a random effect fitted for herd. Postnatal mortality incidence risk was calculated using time at risk for each calf from 24 h of age, collapsed into weeks, and multiplying the incidence risk by the mean weaning age of the study population. Farm-level risk factors contributing to postnatal mortality in the first week of life were assessed using a multivariable logistic mixed regression model. The mean perinatal mortality risk was 5.7% (95% confidence interval 5.4 to 6.1%) with a range from 2.2 to 8.6% (18,437 calves, 30 farms). Perinatal calf mortality was greater for male relative to female calves (odds ratio 1.39; 95% confidence interval 1.22 to 1.59), calves born in the first week of the calving period in comparison to wk 2 to 11 (odds ratio 0.32 to 0.66), and those born on days with greater rainfall (odds ratio 1.01 per 1 mm increase; 95% confidence interval 1.00 to 1.02). At the farm level, perinatal mortality increased for every extra week of calving period length (odds ratio 1.12; 95% confidence interval 1.06 to 1.17). The mean postnatal mortality risk was 4.1% (95% confidence interval 3.6 to 4.6%) with a range of 0 to 11% between farms. Farm-level risk factors contributing to mortality in the first week of life included farmer-reported disease problems in calves (odds ratio 2.2; 95% confidence interval 1.62 to 2.96), or calves hand-fed colostrum in the first 12 h of life (odds ratio 1.66; 95% confidence interval 1.26 to 2.19), which was assumed to be associated with poor colostrum quality and bacterial contamination. Regional differences were also observed in both perinatal and postnatal mortality risks, indicating that weather conditions, herd size, and management variations contribute to mortality incidence. In summary, the mortality risk of perinatal calves and postnatal calves until weaning on pasture-based farms is comparable with data published from other dairying systems despite the notable management differences. Several risk factors were identified that could be managed to reduce mortality incidence of dairy calves. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Durell, Todd M; Adler, Lenard A; Williams, Dave W; Deldar, Ahmed; McGough, James J; Glaser, Paul E; Rubin, Richard L; Pigott, Teresa A; Sarkis, Elias H; Fox, Bethany K
2013-02-01
Attention-deficit/hyperactivity disorder (ADHD) is associated with significant impairment in multiple functional domains. This trial evaluated efficacy in ADHD symptoms and functional outcomes in young adults treated with atomoxetine. Young adults (18-30 years old) with ADHD were randomized to 12 weeks of double-blind treatment with atomoxetine (n = 220) or placebo (n = 225). The primary efficacy measure of ADHD symptom change was Conners' Adult ADHD Rating Scale (CAARS): Investigator-Rated: Screening Version Total ADHD Symptoms score with adult prompts. Secondary outcomes scales included the Adult ADHD Quality of Life-29, Clinical Global Impression-ADHD-Severity, Patient Global Impression-Improvement, CAARS Self-Report, Behavior Rating Inventory of Executive Function-Adult Version Self-Report, and assessments of depression, anxiety, sleepiness, driving behaviors, social adaptation, and substance use. Atomoxetine was superior to placebo on CAARS: Investigator-Rated: Screening Version (atomoxetine [least-squares mean ± SE, -13.6 ± 0.8] vs placebo [-9.3 ± 0.8], 95% confidence interval [-6.35 to -2.37], P < 0.001), Clinical Global Impression-ADHD-Severity (atomoxetine [-1.1 ± 0.1] vs placebo [-0.7 ± 0.1], 95% confidence interval [-0.63 to -0.24], P < 0.001), and CAARS Self-Report (atomoxetine [-11.9 ± 0.8] vs placebo [-7.8 ± 0.7], 95% confidence interval [-5.94 to -2.15], P < 0.001) but not on Patient Global Impression-Improvement. In addition, atomoxetine was superior to placebo on Adult ADHD Quality of Life-29 and Behavior Rating Inventory of Executive Function-Adult Version Self-Report. Additional assessments failed to detect significant differences (P ≥ 0.05) between atomoxetine and placebo. The adverse event profile was similar to that observed in other atomoxetine studies. Nausea, decreased appetite, insomnia, dry mouth, irritability, dizziness, and dyspepsia were reported significantly more often with atomoxetine than with placebo. Atomoxetine reduced ADHD symptoms and improved quality of life and executive functioning deficits in young adults compared with placebo. Atomoxetine was also generally well tolerated.
PTSD, combat injury, and headache in Veterans Returning from Iraq/Afghanistan.
Afari, Niloofar; Harder, Laura H; Madra, Naju J; Heppner, Pia S; Moeller-Bertram, Tobias; King, Clay; Baker, Dewleen G
2009-10-01
To examine the relationship between posttraumatic stress disorder, combat injury, and headache in Operation Iraqi Freedom and Operation Enduring Freedom veterans at the VA San Diego Healthcare System. Previous investigations suggest that a relationship between posttraumatic stress disorder and primary headache disorders exists and could be complicated by the contribution of physical injury, especially one that results in loss of consciousness. These associations have not been systematically examined in Operation Iraqi Freedom and Operation Enduring Freedom veterans. In this observational cross-sectional study, a battery of self-report, standardized questionnaires was completed by 308 newly registered veterans between March and October 2006. The Davidson Trauma Scale was used to determine the degree of posttraumatic stress disorder symptoms and combat-related physical injury was assessed by self-report. The presence of headache was based on a symptom checklist measure and self-reported doctor diagnoses. Logistic regression analysis was performed to predict presence of headache and determine odds ratios and 95% confidence intervals associated with demographic, military, in-theatre, and mental health characteristics. About 40% of the veterans met the criteria for posttraumatic stress disorder; 40% self-reported current headache, 10% reported a physician diagnosis of migraine, 12% a physician diagnosis of tension-type headache, and 6% reported both types of headache. Results from the logistic regression model indicated that combat-related physical injury (odds ratio: 2.25; 95% confidence interval: 1.17-4.33) and posttraumatic stress disorder (odds ratio: 4.13; 95% confidence interval: 2.44-6.99) were independent predictors of self-reported headache. Additional analyses found that veterans with both tension and migraine headache had higher rates of posttraumatic stress disorder (chi-square [d.f. = 3] = 15.89; P = .001) whereas veterans with migraine headache alone had higher rates of combat-related physical injury (chi-square [d.f. = 9] = 22.00; P = .009). Posttraumatic stress disorder and combat-related physical injury were related to higher rates of self-reported headache in newly returning veterans. Our finding that posttraumatic stress disorder and injury during combat are differentially related to migraine and tension-type headache, point to a complex relationship between physical and psychological trauma and headache. These findings have implications for a comprehensive approach to interventions for headache and the physical and psychological sequelae of trauma.
Amort, Margareth; Fluri, Felix; Weisskopf, Florian; Gensicke, Henrik; Bonati, Leo H; Lyrer, Philippe A; Engelter, Stefan T
2012-01-01
In patients with transient ischemic attacks (TIA), etiological classification systems are not well studied. The Trial of ORG 10172 in Acute Stroke Treatment (TOAST), the Causative Classification System (CCS), and the Atherosclerosis Small Vessel Disease Cardiac Source Other Cause (ASCO) classification may be useful to determine the underlying etiology. We aimed at testing the feasibility of each of the 3 systems. Furthermore, we studied and compared their prognostic usefulness. In a single-center TIA registry prospectively ascertained over 2 years, we applied 3 etiological classification systems. We compared the distribution of underlying etiologies, the rates of patients with determined versus undetermined etiology, and studied whether etiological subtyping distinguished TIA patients with versus without subsequent stroke or TIA within 3 months. The 3 systems were applicable in all 248 patients. A determined etiology with the highest level of causality was assigned similarly often with TOAST (35.9%), CCS (34.3%), and ASCO (38.7%). However, the frequency of undetermined causes differed significantly between the classification systems and was lowest for ASCO (TOAST: 46.4%; CCS: 37.5%; ASCO: 18.5%; p < 0.001). In TOAST, CCS, and ASCO, cardioembolism (19.4/14.5/18.5%) was the most common etiology, followed by atherosclerosis (11.7/12.9/14.5%). At 3 months, 33 patients (13.3%, 95% confidence interval 9.3-18.2%) had recurrent cerebral ischemic events. These were strokes in 13 patients (5.2%; 95% confidence interval 2.8-8.8%) and TIAs in 20 patients (8.1%, 95% confidence interval 5.0-12.2%). Patients with a determined etiology (high level of causality) had higher rates of subsequent strokes than those without a determined etiology [TOAST: 6.7% (95% confidence interval 2.5-14.1%) vs. 4.4% (95% confidence interval 1.8-8.9%); CSS: 9.3% (95% confidence interval 4.1-17.5%) vs. 3.1% (95% confidence interval 1.0-7.1%); ASCO: 9.4% (95% confidence interval 4.4-17.1%) vs. 2.6% (95% confidence interval 0.7-6.6%)]. However, this difference was only significant in the ASCO classification (p = 0.036). Using ASCO, there was neither an increase in risk of subsequent stroke among patients with incomplete diagnostic workup (at least one subtype scored 9) compared with patients with adequate workup (no subtype scored 9), nor among patients with multiple causes compared with patients with a single cause. In TIA patients, all etiological classification systems provided a similar distribution of underlying etiologies. The increase in stroke risk in TIA patients with determined versus undetermined etiology was most evident using the ASCO classification. Copyright © 2012 S. Karger AG, Basel.
ERIC Educational Resources Information Center
Onwuegbuzie, Anthony J.; Daniel, Larry G.
The purposes of this paper are to identify common errors made by researchers when dealing with reliability coefficients and to outline best practices for reporting and interpreting reliability coefficients. Common errors that researchers make are: (1) stating that the instruments are reliable; (2) incorrectly interpreting correlation coefficients;…
Chapter 13: Applying GTR 220 Concepts on the Sagehen Experimental Forest
P. Stine; S. Conway
2012-01-01
Applying science to the practice of forest management is a difficult process. Scientific results tend to be expressed in terms such as variances, confidence intervals, and probability distributions. Rarely does science provide unequivocal information, yet land managers must make definitive decisions on the ground. The General Technical Report "An Ecosystem...
Large Sample Confidence Intervals for Item Response Theory Reliability Coefficients
ERIC Educational Resources Information Center
Andersson, Björn; Xin, Tao
2018-01-01
In applications of item response theory (IRT), an estimate of the reliability of the ability estimates or sum scores is often reported. However, analytical expressions for the standard errors of the estimators of the reliability coefficients are not available in the literature and therefore the variability associated with the estimated reliability…
Duplex ultrasound surveillance after carotid artery endarterectomy.
Al Shakarchi, Julien; Lowry, Danielle; Nath, Jay; Khawaja, Aurangzaib Z; Inston, Nicholas; Tiwari, Alok
2016-06-01
After carotid endarterectomy (CEA), patients have been regularly followed up by duplex ultrasound imaging. However, the evidence for long-term follow-up is not clear, especially if the results from an early duplex scan are normal. This study assessed and systematically reviewed the evidence base for long-term surveillance after CEA and a normal early scan. Electronic databases were searched for studies assessing duplex surveillance after CEA in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The primary outcome for this study was the incidence of restenosis after a normal early scan. The secondary outcome was the number of reinterventions after a normal early scan. The review included seven studies that reported 2317 procedures. Of those patients with a normal early scan, 2.8% (95% confidence interval, 0.7%-6%) developed a restenosis, and 0.4% (95% confidence interval, 0%-0.9%) underwent a reintervention for their restenosis during the follow-up period. This review confirms that routine postoperative duplex ultrasound surveillance after CEA is not necessary if the early duplex scan is normal. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.
Calvert, Eric; Chambers, Gordon Keith; Regan, William; Hawkins, Robert H; Leith, Jordan M
2009-05-01
The diagnosis of a superior labrum anterior posterior (SLAP) lesion through physical examination has been widely reported in the literature. Most of these studies report high sensitivities and specificities, and claim to be accurate, valid, and reliable. The purpose of this study was to critically evaluate these studies to determine if there was sufficient evidence to support the use of the SLAP physical examination tests as valid and reliable diagnostic test procedures. Strict epidemiologic methodology was used to obtain and collate all relevant articles. Sackett's guidelines were applied to all articles. Confidence intervals and likelihood ratios were determined. Fifteen of 29 relevant studies met the criteria for inclusion. Only one article met all of Sackett's critical appraisal criteria. Confidence intervals for both the positive and negative likelihood ratios contained the value 1. The current literature being used as a resource for teaching in medical schools and continuing education lacks the validity necessary to be useful. There are no good physical examination tests that exist for effectively diagnosing a SLAP lesion.
Labandeira-Rey, Maria; Janowicz, Diane M; Blick, Robert J; Fortney, Kate R; Zwickl, Beth; Katz, Barry P; Spinola, Stanley M; Hansen, Eric J
2009-08-01
Haemophilus ducreyi 35000HP contains a homologue of the luxS gene, which encodes an enzyme that synthesizes autoinducer 2 (AI-2) in other gram-negative bacteria. H. ducreyi 35000HP produced AI-2 that functioned in a Vibrio harveyi-based reporter system. A H. ducreyi luxS mutant was constructed by insertional inactivation of the luxS gene and lost the ability to produce AI-2. Provision of the H. ducreyi luxS gene in trans partially restored AI-2 production by the mutant. The luxS mutant was compared with its parent for virulence in the human challenge model of experimental chancroid. The pustule-formation rate in 5 volunteers was 93.3% (95% confidence interval, 81.7%-99.9%) at 15 parent sites and 60.0% (95% confidence interval, 48.3%-71.7%) at 15 mutant sites (1-tailed P < .001). Thus, the luxS mutant was partially attenuated for virulence. This is the first report of AI-2 production contributing to the pathogenesis of a genital ulcer disease.
National Practice Patterns of Obtaining Informed Consent for Stroke Thrombolysis.
Mendelson, Scott J; Courtney, D Mark; Gordon, Elisa J; Thomas, Leena F; Holl, Jane L; Prabhakaran, Shyam
2018-03-01
No standard approach to obtaining informed consent for stroke thrombolysis with tPA (tissue-type plasminogen activator) currently exists. We aimed to assess current nationwide practice patterns of obtaining informed consent for tPA. An online survey was developed and distributed by e-mail to clinicians involved in acute stroke care. Multivariable logistic regression analyses were performed to determine independent factors contributing to always obtaining informed consent for tPA. Among 268 respondents, 36.7% reported always obtaining informed consent and 51.8% reported the informed consent process caused treatment delays. Being an emergency medicine physician (odds ratio, 5.8; 95% confidence interval, 2.9-11.5) and practicing at a nonacademic medical center (odds ratio, 2.1; 95% confidence interval, 1.0-4.3) were independently associated with always requiring informed consent. The most commonly cited cause of delay was waiting for a patient's family to reach consensus about treatment. Most clinicians always or often require informed consent for stroke thrombolysis. Future research should focus on standardizing content and delivery of tPA information to reduce delays. © 2018 American Heart Association, Inc.
Genetic influences on variation in female orgasmic function: a twin study
Dunn, Kate M; Cherkas, Lynn F; Spector, Tim D
2005-01-01
Orgasmic dysfunction in females is commonly reported in the general population with little consensus on its aetiology. We performed a classical twin study to explore whether there were observable genetic influences on female orgasmic dysfunction. Adult females from the TwinsUK register were sent a confidential survey including questions on sexual problems. Complete responses to the questions on orgasmic dysfunction were obtained from 4037 women consisting of 683 monozygotic and 714 dizygotic pairs of female twins aged between 19 and 83 years. One in three women (32%) reported never or infrequently achieving orgasm during intercourse, with a corresponding figure of 21% during masturbation. A significant genetic influence was seen with an estimated heritability for difficulty reaching orgasm during intercourse of 34% (95% confidence interval 27–40%) and 45% (95% confidence interval 38–52%) for orgasm during masturbation. These results show that the wide variation in orgasmic dysfunction in females has a genetic basis and cannot be attributed solely to cultural influences. These results should stimulate further research into the biological and perhaps evolutionary processes governing female sexual function. PMID:17148182
Genetic influences on variation in female orgasmic function: a twin study.
Dunn, Kate M; Cherkas, Lynn F; Spector, Tim D
2005-09-22
Orgasmic dysfunction in females is commonly reported in the general population with little consensus on its aetiology. We performed a classical twin study to explore whether there were observable genetic influences on female orgasmic dysfunction. Adult females from the TwinsUK register were sent a confidential survey including questions on sexual problems. Complete responses to the questions on orgasmic dysfunction were obtained from 4037 women consisting of 683 monozygotic and 714 dizygotic pairs of female twins aged between 19 and 83 years. One in three women (32%) reported never or infrequently achieving orgasm during intercourse, with a corresponding figure of 21% during masturbation. A significant genetic influence was seen with an estimated heritability for difficulty reaching orgasm during intercourse of 34% (95% confidence interval 27-40%) and 45% (95% confidence interval 38-52%) for orgasm during masturbation. These results show that the wide variation in orgasmic dysfunction in females has a genetic basis and cannot be attributed solely to cultural influences. These results should stimulate further research into the biological and perhaps evolutionary processes governing female sexual function.
Likelihood-based confidence intervals for estimating floods with given return periods
NASA Astrophysics Data System (ADS)
Martins, Eduardo Sávio P. R.; Clarke, Robin T.
1993-06-01
This paper discusses aspects of the calculation of likelihood-based confidence intervals for T-year floods, with particular reference to (1) the two-parameter gamma distribution; (2) the Gumbel distribution; (3) the two-parameter log-normal distribution, and other distributions related to the normal by Box-Cox transformations. Calculation of the confidence limits is straightforward using the Nelder-Mead algorithm with a constraint incorporated, although care is necessary to ensure convergence either of the Nelder-Mead algorithm, or of the Newton-Raphson calculation of maximum-likelihood estimates. Methods are illustrated using records from 18 gauging stations in the basin of the River Itajai-Acu, State of Santa Catarina, southern Brazil. A small and restricted simulation compared likelihood-based confidence limits with those given by use of the central limit theorem; for the same confidence probability, the confidence limits of the simulation were wider than those of the central limit theorem, which failed more frequently to contain the true quantile being estimated. The paper discusses possible applications of likelihood-based confidence intervals in other areas of hydrological analysis.
Agreement and accuracy using the FIGO, ACOG and NICE cardiotocography interpretation guidelines.
Santo, Susana; Ayres-de-Campos, Diogo; Costa-Santos, Cristina; Schnettler, William; Ugwumadu, Austin; Da Graça, Luís M
2017-02-01
One of the limitations reported with cardiotocography is the modest interobserver agreement observed in tracing interpretation. This study compared agreement, reliability and accuracy of cardiotocography interpretation using the International Federation of Gynecology and Obstetrics, American College of Obstetrics and Gynecology and National Institute for Health and Care Excellence guidelines. A total of 151 tracings were evaluated by 27 clinicians from three centers where International Federation of Gynecology and Obstetrics, American College of Obstetrics and Gynecology and National Institute for Health and Care Excellence guidelines were routinely used. Interobserver agreement was evaluated using the proportions of agreement and reliability with the κ statistic. The accuracy of tracings classified as "pathological/category III" was assessed for prediction of newborn acidemia. For all measures, 95% confidence interval were calculated. Cardiotocography classifications were more distributed with International Federation of Gynecology and Obstetrics (9, 52, 39%) and National Institute for Health and Care Excellence (30, 33, 37%) than with American College of Obstetrics and Gynecology (13, 81, 6%). The category with the highest agreement was American College of Obstetrics and Gynecology category II (proportions of agreement = 0.73, 95% confidence interval 0.70-76), and the ones with the lowest agreement were American College of Obstetrics and Gynecology categories I and III. Reliability was significantly higher with International Federation of Gynecology and Obstetrics (κ = 0.37, 95% confidence interval 0.31-0.43), and National Institute for Health and Care Excellence (κ = 0.33, 95% confidence interval 0.28-0.39) than with American College of Obstetrics and Gynecology (κ = 0.15, 95% confidence interval 0.10-0.21); however, all represent only slight/fair reliability. International Federation of Gynecology and Obstetrics and National Institute for Health and Care Excellence showed a trend towards higher sensitivities in prediction of newborn acidemia (89 and 97%, respectively) than American College of Obstetrics and Gynecology (32%), but the latter achieved a significantly higher specificity (95%). With American College of Obstetrics and Gynecology guidelines there is high agreement in category II, low reliability, low sensitivity and high specificity in prediction of acidemia. With International Federation of Gynecology and Obstetrics and National Institute for Health and Care Excellence guidelines there is higher reliability, a trend towards higher sensitivity, and lower specificity in prediction of acidemia. © 2016 Nordic Federation of Societies of Obstetrics and Gynecology.
Repetitive Transcranial Magnetic Stimulation (rTMS) Therapy in Parkinson Disease: A Meta-Analysis.
Wagle Shukla, Aparna; Shuster, Jonathan J; Chung, Jae Woo; Vaillancourt, David E; Patten, Carolynn; Ostrem, Jill; Okun, Michael S
2016-04-01
Several studies have reported repetitive transcranial magnetic stimulation (rTMS) therapy as an effective treatment for the control of motor symptoms in Parkinson disease. The objective of the study is to quantify the overall efficacy of this treatment. Systematic review and meta-analysis. We reviewed the literature on clinical rTMS trials in Parkinson disease since the technique was introduced in 1980. We used the following databases: MEDLINE, Web of Science, Cochrane, and CINAHL. Patients with Parkinson disease who were participating in prospective clinical trials that included an active arm and a control arm and change in motor scores on Unified Parkinson's Disease Rating Scale as the primary outcome. We pooled data from 21 studies that met these criteria. We then analyzed separately the effects of low- and high-frequency rTMS on clinical motor improvements. The overall pooled mean difference between treatment and control groups in the Unified Parkinson's Disease Rating Scale motor score was significant (4.0 points, 95% confidence interval, 1.5, 6.7; P = .005). rTMS therapy was effective when low-frequency stimulation (≤ 1 Hz) was used with a pooled mean difference of 3.3 points (95% confidence interval 1.6, 5.0; P = .005). There was a trend for significance when high-frequency stimulation (≥ 5 Hz) studies were evaluated with a pooled mean difference of 3.9 points (95% confidence interval, -0.7, 8.5; P = .08). rTMS therapy demonstrated benefits at short-term follow-up (immediately after a treatment protocol) with a pooled mean difference of 3.4 points (95% confidence interval, 0.3, 6.6; P = .03) as well as at long-term follow-up (average follow-up 6 weeks) with mean difference of 4.1 points (95% confidence interval, -0.15, 8.4; P = .05). There were insufficient data to statistically analyze the effects of rTMS when we specifically examined bradykinesia, gait, and levodopa-induced dyskinesia using quantitative methods. rTMS therapy in patients with Parkinson disease results in mild-to-moderate motor improvements and has the potential to be used as an adjunct therapy for the treatment of Parkinson disease. Future large, sample studies should be designed to isolate the specific clinical features of Parkinson disease that respond well to rTMS therapy. Copyright © 2016 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.
Robien, Kim; Bigler, Jeannette; Yasui, Yutaka; Potter, John D; Martin, Paul; Storb, Rainer; Ulrich, Cornelia M
2006-09-01
Methylenetetrahydrofolate reductase (MTHFR) and thymidylate synthase (TS) play key roles in intracellular folate metabolism. Polymorphisms in these enzymes have been shown to modify toxicity of methotrexate (MTX) after hematopoietic cell transplantation. In this study, we evaluated the risk of acute graft-versus-host disease (GVHD) associated with genetic variation in recipient and donor MTHFR and TS genotypes to assess whether genotype alters the efficacy of MTX in acute GVHD prophylaxis. Data on the transplantation course were abstracted from medical records for 304 adults who received allogeneic hematopoietic cell transplants. MTHFR (C677T and A1298C) and TS (enhancer-region 28-base pair repeat, TSER, and 1494del6) genotypes were determined using polymerase chain reaction/restriction fragment length polymorphism and TaqMan assays. Multivariable logistic regression was used to assess the associations between genotypes and risk of acute GVHD. Compared with recipients with the wild-type MTHFR 677CC genotype, those with the variant 677T allele showed a decreased risk of detectable acute GVHD (677CT: odds ratio, 0.8; 95% confidence interval, 0.4-1.6; 677TT: odds ratio, 0.4; 95% confidence interval, 0.2-0.8; P for trend = .01). The variant MTHFR 1298C allele in recipients was associated with an increased risk of acute GVHD compared with the wild-type MTHFR 1298AA genotype (1298AC: odds ratio, 2.0; 95% confidence interval, 1.1-3.9; 1298CC: odds ratio, 3.6; 95% confidence interval, 1.0-12.7; P for trend < .01). No association with risk of acute GVHD was observed for donor MTHFR genotypes or for recipient or donor TS genotypes, with the exception of an increase in acute GVHD among recipients whose donors had the TSER 3R/2R genotype (odds ratio, 3.0; 95% confidence interval, 1.3-7.2). These findings indicate that host, but not donor, MTHFR genotypes modify the risk of acute GVHD in recipients receiving MTX, in a manner consistent with our previously reported associations between MTHFR genotypes and MTX toxicity. A direct trade-off between drug toxicity and drug efficacy may play a role. Alternatively, the systemic folate environment, regulated by host tissues, might influence donor T-cell growth and activity.
Kubo, Ai; Ferrara, Assiamira; Laurent, Cecile A.; Windham, Gayle C.; Greenspan, Louise C.; Deardorff, Julianna; Hiatt, Robert A.; Quesenberry, Charles P.; Kushi, Lawrence H.
2016-01-01
Abstract We investigated whether in utero exposure to maternal pregravid obesity and/or gestational diabetes mellitus (GDM) was associated with early puberty in girls. We used data from a longitudinal study of 421 mother-daughter pairs enrolled in an integrated health services organization, Kaiser Permanente Northern California (2005–2012). Girls aged 6–8 years were followed annually through ages 12–14 years. Onset of puberty was assessed using study clinic-based Tanner staging. We examined associations of self-reported pregravid obesity and maternal GDM with timing of the daughter's transition to pubertal maturation stage 2 or above for development of breasts and pubic hair, using accelerated failure time regression models with interval censoring to estimate time ratios and hazard ratios and corresponding 95% confidence intervals. Maternal obesity (pregravid body mass index (BMI; weight (kg)/height (m)2) ≥30) was associated with a daughter's earlier transition to breast and pubic hair stage 2+ in comparison with girls whose mothers had pregravid BMI <25. These associations were attenuated and not statistically significant after adjustment for covariates. Girls whose mothers had both pregravid BMI ≥25 and GDM were at higher risk of an earlier transition to pubic hair stage 2+ than those whose mothers had neither condition (adjusted time ratio = 0.89, 95% confidence interval: 0.83, 0.96; hazard ratio = 2.97, 95% confidence interval: 1.52, 5.83). These findings suggest that exposure to maternal obesity and hyperglycemia places girls at higher risk of earlier pubarche. PMID:27268032
Hazard ratio estimation and inference in clinical trials with many tied event times.
Mehrotra, Devan V; Zhang, Yiwei
2018-06-13
The medical literature contains numerous examples of randomized clinical trials with time-to-event endpoints in which large numbers of events accrued over relatively short follow-up periods, resulting in many tied event times. A generally common feature across such examples was that the logrank test was used for hypothesis testing and the Cox proportional hazards model was used for hazard ratio estimation. We caution that this common practice is particularly risky in the setting of many tied event times for two reasons. First, the estimator of the hazard ratio can be severely biased if the Breslow tie-handling approximation for the Cox model (the default in SAS and Stata software) is used. Second, the 95% confidence interval for the hazard ratio can include one even when the corresponding logrank test p-value is less than 0.05. To help establish a better practice, with applicability for both superiority and noninferiority trials, we use theory and simulations to contrast Wald and score tests based on well-known tie-handling approximations for the Cox model. Our recommendation is to report the Wald test p-value and corresponding confidence interval based on the Efron approximation. The recommended test is essentially as powerful as the logrank test, the accompanying point and interval estimates of the hazard ratio have excellent statistical properties even in settings with many tied event times, inferential alignment between the p-value and confidence interval is guaranteed, and implementation is straightforward using commonly used software. Copyright © 2018 John Wiley & Sons, Ltd.
Del Rio, Paolo; Iapichino, Gioacchino; De Simone, Belinda; Bezer, Lamia; Arcuri, MariaFrancesca; Sianesi, Mario
2010-01-01
Hypocalcaemia is the most frequent complication after total thyroidectomy. The incidence of postoperative hypocalcaemia is reported with different percentages in literature. We report 227 patients undergoing surgery for benign thyroid disease. After obtaining patient's informed consent, we collected and analyzed prospectively the following data: calcium serum levels pre and postoperative in the first 24 hours after surgery according to sex, age, duration of surgery, number of parathyroids identified by the surgeon, surgical technique (open and minimally invasive video-assisted thyroidectomy, i.e., MIVAT). We have considered cases treated consecutively from the same two experienced endocrine surgeons. Hypocalcaemia is assumed when the value of serum calcium is below 7.5 mg/dL. Pre-and post-operative mean serum calcium, with confidence intervals at 99% divided by sex, revealed a statistically significant difference in the ANOVA test (p < 0.01) in terms of incidence. Female sex has higher incidence of hypocalcemia. The evaluation of the mean serum calcium in pre-and post-operative period, with confidence intervals at 95%, depending on the number of identified parathyroid glands by surgeon, showed that the result is not correlated with values of postoperative serum calcium. Age and pre-and postoperative serum calcium values with confidence intervals at 99% based on sex of patients, didn't show statistically significant differences. We haven't highlighted a significant difference in postoperative hypocalcemia in patients treated with conventional thyroidectomy versus MIVAT. A difference in pre- and postoperative mean serum calcium occurs in all patients surgically treated. The only statistical meaningful risk factor for hypocalcemia has been the female sex.
Bottled, filtered, and tap water use in Latino and non-Latino children.
Hobson, Wendy L; Knochel, Miguel L; Byington, Carrie L; Young, Paul C; Hoff, Charles J; Buchi, Karen F
2007-05-01
To describe bottled, filtered, and tap water consumption and fluoride use among pediatric patients; to analyze differences between ethnic and socioeconomic groups; and to describe the frequency of physician-parent discussions regarding water consumption. Convenience sample survey. An urban public health clinic. Parents attending a public health clinic. The primary outcome measure was the prevalence of tap, filtered, and bottled water use. The secondary outcome measures were supplemental fluoride use and the percentage of patients reporting discussions of water consumption with their physician. A total of 216 parents (80.5% Latino and 19.5% non-Latino) completed the survey. Of the parents, 30.1% never drank tap water and 41.2% never gave it to their children. Latino parents were less likely than non-Latino parents to drink tap water (odds ratio, 0.26; 95% confidence interval, 0.10-0.67) and less likely to give tap water to their children (odds ratio, 0.32; 95% confidence interval, 0.15-0.70). More Latinos believed that tap water would make them sick (odds ratio, 5.63; 95% confidence interval, 2.17-14.54). Approximately 40% of children who never drank tap water were not receiving fluoride supplements. Of the lowest-income families (
Screening for Behavioral Risk Factors Is Not Enough to Improve Preventive Services Delivery.
Drouin, Olivier; Winickoff, Jonathan P
Unhealthy behaviors are a major cause of chronic disease. Preappointment screening has been suggested as one way to improve preventive care delivery related to these behaviors by specifying risks to be addressed. We aimed to determine whether screening for health-related behaviors before the clinical encounter will lead to higher counseling rate and service delivery by clinicians. We used a pre/post design in one practice with a control practice to evaluate the effects of preappointment screening for 3 behavioral risk factors (tobacco smoke exposure, no recent dental care visit, and consumption of sugar-sweetened beverages). After their clinic visit, we asked English-speaking parents whose child had one or more risk factor whether they had received counseling or services from their pediatrician to address them. We recruited 264 parents in the pre phase and 242 in the post phase. Among 215 parents whose child had one or more risk factors, parents in the post phase were as likely to report receiving counseling than parents in the pre phase for each of the risk factors: smoking odds ratio 6.75 (95% confidence interval, 0.51, 88.88), dental health odds ratio 1.44 (95% confidence interval, 0.47, 4.41), and sugar-sweetened beverage consumption odds ratio 0.34 (95% confidence interval, 0.23, 5.18). Service delivery and reported behavior change were also similar in both phases. Counseling rates for tobacco, dental health, or sugar-sweetened beverage consumption were low in pediatric primary care, and preappointment screening did not significantly affect clinician counseling. Future efforts will require a more robust approach to effect change in counseling, provision of service, and family behavior. Copyright © 2018 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.
Wellman, Robert J; Sugarman, David B; DiFranza, Joseph R; Winickoff, Jonathan P
2006-12-01
To quantify the effect of exposure on initiation of tobacco use among adolescents. A systematic literature search of MEDLINE, PsychINFO, ABI/INFORM, and Business Source Premier through October/November 2005 was conducted. Unpublished studies were solicited from researchers. Of 401 citations initially identified, 51 (n = 141 949 participants) met the inclusion criteria: reporting on exposure and tobacco use outcomes and participants younger than 18 years. Included studies reported 146 effects; 89 were conceptually independent effects. Data were extracted independently by 3 of us using a standardized tool. Weighted averages were calculated using a linear mixed-effects model. Heterogeneity and publication bias were assessed. Main Exposures Exposures (tobacco advertising, promotions, and samples and pro-tobacco depictions in films, television, and videos) were categorized as low or high engagement based on the degree of psychological involvement required. Outcomes were categorized as cognitive (attitudes or intentions) or behavioral (initiation, tobacco use status, or progression of use). Exposure to pro-tobacco marketing and media increases the odds of youth holding positive attitudes toward tobacco use (odds ratio, 1.51; 95% confidence interval, 1.08-2.13) and more than doubles the odds of initiating tobacco use (odds ratio, 2.23; 95% confidence interval, 1.79-2.77). Highly engaging marketing and media are more effective at promoting use (odds ratio, 2.67; 95% confidence interval, 2.19-3.25). These effects are observed across time, in different countries, with different study designs and measures of exposure and outcome. Pro-tobacco marketing and media stimulate tobacco use among youth. A ban on all tobacco promotions is warranted to protect children.
Miller, Alison L; Gearhardt, Ashley N; Retzloff, Lauren; Sturza, Julie; Kaciroti, Niko; Lumeng, Julie C
2018-01-31
To identify whether psychosocial stress exposure during early childhood predicts subsequent increased eating in the absence of hunger (EAH), emotional overeating, food responsiveness, and enjoyment of food. This was an observational longitudinal study. Among 207 low-income children (54.6% non-Hispanic white, 46.9% girls), early childhood stress exposure was measured by parent report and a stress exposure index calculated, with higher scores indicating more stress exposure. Eating behaviors were measured in early (mean, 4.3; standard deviation, 0.5 years) and middle (mean, 7.9; standard deviation, 0.7 years) childhood. Observed EAH was assessed by measuring kilocalories of palatable food the child consumed after a meal. Parents reported on child eating behaviors on the Child Eating Behavior Questionnaire. Child weight and height were measured and body mass index z score (BMIz) calculated. Multivariable linear regression, adjusting for child sex, race/ethnicity, and BMIz, was used to examine the association of stress exposure with rate of change per year in each child eating behavior. Early childhood stress exposure predicted yearly increases in EAH (β = 0.14; 95% confidence interval, 0.002, 0.27) and Emotional Overeating (β = 0.14; 95% confidence interval, 0.008, 0.27). Stress exposure was not associated with Food Responsiveness (trend for decreased Enjoyment of Food; β = -0.13; 95% confidence interval, 0.002, -0.26). All child obesogenic eating behaviors increased with age (P < .05). Early stress exposure predicted increases in child eating behaviors known to associate with overweight/obesity. Psychosocial stress may confer overweight/obesity risk through eating behavior pathways. Targeting eating behaviors may be an important prevention strategy for children exposed to stress. Copyright © 2018 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.
Lemp, G F; Hirozawa, A M; Givertz, D; Nieri, G N; Anderson, L; Lindegren, M L; Janssen, R S; Katz, M
1994-08-10
To estimate the prevalence of human immunodeficiency virus (HIV) infection and risk behaviors among young homosexual and bisexual men sampled from public venues in San Francisco and Berkeley, Calif. A survey of 425 young homosexual and bisexual men sampled from 26 locations during 1992 and 1993. Participants were interviewed and blood specimens were drawn and tested for HIV, level of CD4+ T lymphocytes, and markers of hepatitis B and syphilis. Public venues in San Francisco and Berkeley, including street corners and sidewalks, dance clubs, bars, and parks. Homosexual and bisexual men aged 17 to 22 years. Prevalence of HIV infection and risk behaviors. The HIV seroprevalence was 9.4% (95% confidence interval, 6.8% to 12.6%). The prevalence of markers for hepatitis B was 19.8% (95% confidence interval, 16.1% to 23.9%), and that for syphilis was 1.0% (95% confidence interval, 0.3% to 2.4%). The HIV seroprevalence was significantly higher among African Americans (21.2%) than among other racial/ethnic groups (P = .002). Approximately one third (32.7%) of the participants reported unprotected anal intercourse, and 11.8% reported injecting drug use in the previous 6 months. At the time of interview, 70.0% of the HIV-infected men did not know that they were HIV seropositive, and only 22.5% were receiving medical care for HIV infection. The prevalence of HIV infection is high among this young population of homosexual and bisexual men, particularly among young African-American men. The high rates of HIV-related risk behaviors suggest a considerable risk for HIV transmission in this population. Prevention programs and health services need to be tailored to address the needs of a new generation of homosexual and bisexual men.
Fives, Cassie; Nae, Andreea; Roche, Phoebe; O'Leary, Gerard; Fitzgerald, Brendan; Feeley, Linda; Sheahan, Patrick
2017-04-01
Previous studies have reported variable results for the impact of bone invasion on survival in oral cancer. It is unclear whether bone invasion in small (≤4 cm) squamous cell carcinomas (SCC) of the oral cavity is an independent adverse prognosticator. Our objective was to investigate impact on survival of bone invasion in SCC of floor of mouth (FOM), lower alveolus (LA), and retromolar trigone (RMT) ≤4 cm in size. Retrospective study of 96 patients with SCC of the FOM, LA, and RMT undergoing primary surgical treatment. Original pathology reports and slides were reviewed by three pathologists. Level of bone invasion was categorized as cortical or medullary. Main outcome measures were local control (LC) and overall survival (OS). Bone invasion was present in 31 cases (32%). On review of pathology slides, all cases of bone invasion demonstrated medullary involvement. Median follow-up was 36 months for all patients, and 53 months for patients not dying from cancer. Among tumors ≤4 cm, bone invasion was associated with significantly worse LC (P =.04) and OS (P =.0005). Medullary invasion (hazard ratio: 2.2, 95% confidence interval: 1.1-4.4, P =.03), postoperative radiotherapy (hazard ratio: 0.3, 95% confidence interval: 0.1-0.5, P <.001), and positive pathologic nodal status (hazard ratio: 4.1, 95% confidence interval: 1.9-8.6, P <.001) were independent predictors of worse OS among the entire cohort. Mandibular medullary bone invasion is a poor prognosticator in oral cancers, irrespective of small size of primary tumor. Such cases should be considered for postoperative radiotherapy. 4. Laryngoscope, 127:849-854, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.
Johansson, Magdalena; Lind, Marcus; Jansson, Jan-Håkan; Fhärm, Eva; Johansson, Lars
2018-05-01
It remains unclear whether high plasma glucose levels are associated with venous thromboembolism (VTE). This study investigated the association between fasting plasma glucose (FPG), oral glucose tolerance test (two-hour post-load plasma glucose (2HPG)), diabetes, and VTE. The population-based, prospective Venous thromboEmbolism In Northern Sweden (VEINS) cohort study included 108,025 residents of Västerbotten County in northern Sweden. The participants were aged 30 to 60 years and had no previous VTE events. They were included from 1985 onwards and were followed until a VTE event, death, emigration, or the study end on September 5, 2014. All underwent a health examination that measured weight, height, FPG, and 2HPG and included a questionnaire regarding smoking, education level, and history of diabetes. Potential VTE events were identified by an extensive diagnosis registry search and were validated by reviewing medical records and radiology reports. An objectively verified first-time VTE event was experienced by 2054 participants during 1,496,669 person-years of follow-up. In univariable analysis, there were associations between FPG, 2HPG, diabetes, and the risk of VTE. These associations disappeared after adjustment for potential confounders (age, sex, body mass index, cancer at inclusion, education level, smoking, and hypertension). The adjusted hazard ratios were 1.01 (95% confidence interval 0.83-1.23) for diabetes, 1.01 for each standard deviation of FPG (95% confidence interval 0.97-1.05), and 0.96 for each standard deviation of 2HPG (95% confidence interval 0.91-1.00). There were no independent associations between FPG, 2HPG, diabetes, and future risk of VTE. Copyright © 2018 Elsevier Ltd. All rights reserved.
Socioeconomic status inconsistency and risk of stroke among Japanese middle-aged women.
Honjo, Kaori; Iso, Hiroyasu; Inoue, Manami; Sawada, Norie; Tsugane, Shoichiro
2014-09-01
Little research has been conducted to examine the effect of inconsistencies in socioeconomic status on cardiovascular health. In particular, no studies have been reported in Asian countries, including Japan, which is thought to have high socioeconomic status inconsistency among women. We examined the effect of status inconsistency between education level and occupation on stroke risk in a prospective 20-year study of 14 742 middle-aged Japanese women included in the prospective Japan Public Health Center-based (JPHC) Study Cohort I in 1990. Status inconsistency between education level and occupation was determined (qualified, overqualified, and underqualified), and the association with risk of stroke was examined. Cox proportional regression analysis was used to determine hazard ratios, which were adjusted for age, marital status, and geographical area. Adjusted hazard ratio for stroke in overqualified compared with qualified women was 2.06 (95% confidence interval, 1.13-3.78). Adjusted hazard ratios for stroke among highly educated manual workers and workers in service industry were 3.47 (95% confidence interval, 1.54-7.84) and 3.21 (95% confidence interval, 1.49-6.90), respectively, when compared with highly educated professionals/managers. High academic qualifications without an appropriate job could be a risk factor for stroke among Japanese women. Our result suggests that status inconsistency could be a potential explanation for the increased stroke risk among highly educated women. © 2014 American Heart Association, Inc.
Reliable change of the sensory organization test.
Broglio, Steven P; Ferrara, Michael S; Sopiarz, Kay; Kelly, Michael S
2008-03-01
To establish the sensitivity and specificity of the NeuroCom Sensory Organization Test (SOT) and provide practitioners with cut-scores for clinical decision making using estimates of reliable change. Retrospective cohort study. Research laboratory. Healthy (n = 66) and concussed (n = 63) young adult participants. Postural control assessments on the NeuroCom SOT were completed twice (baseline and follow-up) for both groups. Postconcussion assessments were administered within 24 hours of injury diagnosis. The reliable change technique was used to calculated cut-scores for each SOT variable (composite balance; somatosensory, visual, and vestibular ratios) at the 95%, 90%, 85%, 80%, 75%, and 70% confidence interval levels. When cut-scores were applied to the post-concussion evaluations, sensitivity and specificity varied with SOT variable and confidence interval. An evaluation for change on one or more SOT variable resulted in the highest combined sensitivity (57%) and specificity (80%) at the 75% confidence interval. Use of reliable change scores to detect significant changes in performance on the SOT resulted in decreased sensitivity and improved specificity compared to a previous report. These findings indicate that some concussed athletes may not show large changes in postconcussion postural control and this postural control evaluation should not be used in exclusion of other assessment techniques. The postural control assessment should be combined with other evaluative measures to gain the highest sensitivity to concussive injuries.
Lo, Suzanne H S; Chang, Anne M; Chau, Janita P C
2018-03-01
Evidence shows self-management programs are associated with improved recovery outcomes. This article reports on the effectiveness of a new nurse-led self-efficacy-based stroke self-management program. A randomized controlled trial of participants recruited from 3 acute stroke units was conducted. The intervention group received the 4-week stroke self-management program. The control group received usual care. All participants were assessed at baseline and 8 weeks after randomization. Data were analyzed using generalized estimating equations. Outcomes included self-efficacy, outcome expectation, and satisfaction with performance of self-management behaviors. One hundred twenty-eight participants were randomized with mean age, 67.46 years (SD, 11.95); 59% men; and mean duration poststroke, 45 days (SD, 26.16). At 8 weeks of follow-up in the intention-to-treat population, the intervention group improved significantly in self-efficacy (95% confidence interval, 2.55-12.45; P <0.01), outcome expectation (95% confidence interval, 5.47-14.01; P <0.01), and satisfaction with performance of self-management behaviors (95% confidence interval, 3.38-13.87; P <0.01) compared with the control. Similar results were obtained at 8 weeks of follow-up in the per-protocol population. The stroke self-management program improved survivors' self-efficacy, outcome expectation, and satisfaction with performance of self-management behaviors. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02112955. © 2018 American Heart Association, Inc.
2010-01-01
Background A community in northern Italy was previously reported to have an excess incidence of amyotrophic lateral sclerosis among residents exposed to high levels of inorganic selenium in their drinking water. Methods To assess the extent to which such association persisted in the decade following its initial observation, we conducted a population-based case-control study encompassing forty-one newly-diagnosed cases of amyotrophic lateral sclerosis and eighty-two age- and sex-matched controls. We measured long-term intake of inorganic selenium along with other potentially neurotoxic trace elements. Results We found that consumption of drinking water containing ≥ 1 μg/l of inorganic selenium was associated with a relative risk for amyotrophic lateral sclerosis of 5.4 (95% confidence interval 1.1-26) after adjustment for confounding factors. Greater amounts of cumulative inorganic selenium intake were associated with progressively increasing effects, with a relative risk of 2.1 (95% confidence interval 0.5-9.1) for intermediate levels of cumulative intake and 6.4 (95% confidence interval 1.3-31) for high intake. Conclusion Based on these results, coupled with other epidemiologic data and with findings from animal studies that show specific toxicity of the trace element on motor neurons, we hypothesize that dietary intake of inorganic selenium through drinking water increases the risk for amyotrophic lateral sclerosis. PMID:21134276
Rudant, Jérémie; Lightfoot, Tracy; Urayama, Kevin Y.; Petridou, Eleni; Dockerty, John D.; Magnani, Corrado; Milne, Elizabeth; Spector, Logan G.; Ashton, Lesley J.; Dessypris, Nikolaos; Kang, Alice Y.; Miller, Margaret; Rondelli, Roberto; Simpson, Jill; Stiakaki, Eftichia; Orsi, Laurent; Roman, Eve; Metayer, Catherine; Infante-Rivard, Claire; Clavel, Jacqueline
2015-01-01
The associations between childhood acute lymphoblastic leukemia (ALL) and several proxies of early stimulation of the immune system, that is, day-care center attendance, birth order, maternally reported common infections in infancy, and breastfeeding, were investigated by using data from 11 case-control studies participating in the Childhood Leukemia International Consortium (enrollment period: 1980–2010). The sample included 7,399 ALL cases and 11,181 controls aged 2–14 years. The data were collected by questionnaires administered to the parents. Pooled odds ratios and 95% confidence intervals were estimated by unconditional logistic regression adjusted for age, sex, study, maternal education, and maternal age. Day-care center attendance in the first year of life was associated with a reduced risk of ALL (odds ratio = 0.77, 95% confidence interval: 0.71, 0.84), with a marked inverse trend with earlier age at start (P < 0.0001). An inverse association was also observed with breastfeeding duration of 6 months or more (odds ratio = 0.86, 95% confidence interval: 0.79, 0.94). No significant relationship with a history of common infections in infancy was observed even though the odds ratio was less than 1 for more than 3 infections. The findings of this large pooled analysis reinforce the hypothesis that day-care center attendance in infancy and prolonged breastfeeding are associated with a decreased risk of ALL. PMID:25731888
Gamma Knife Treatment of Growing Vestibular Schwannoma in Norway: A Prospective Study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Varughese, Jobin Kotakkathu, E-mail: jobinv@gmail.com; Wentzel-Larsen, Tore; Centre for Child and Adolescent Mental Health, Eastern and Southern Norway, Oslo
2012-10-01
Purpose: Gamma Knife radiosurgery (GKRS) has been increasingly used in the treatment of vestibular schwannoma (VS). Very few studies relate tumor control and post-treatment growth rates to pretreatment growth rates. Methods and Materials: We prospectively included 45 consecutive VS patients who were initially treated conservatively and then received GKRS between 2000 and 2007 because of demonstrated tumor growth. Pretreatment and post-treatment tumor volumes were estimated. Patients underwent audiograms, reported their symptoms, and responded to the Short Form General Health Survey (SF-36) questionnaire on each visit. Results: Volume doubling times before and after treatment were 1.36 years (95% confidence intervals, 1.14-1.68)more » and -13.1 years (95% confidence intervals, -111.0 to -6.94), respectively. Tumor control, defined as a post-GKRS growth rate {<=}0, was achieved in 71.1% of patients, with highest odds for tumor control among older patients and those with larger tumors. The 5-year retreatment-free survival rate was 93.9% (95% confidence intervals, 76.5-98.5). None of the clinical endpoints investigated showed statistically significant changes after GKRS, but improvement was seen in a few SF-36 parameters. Conclusions: GKRS alters the natural course of the tumor by reducing growth. Mathematic models yield poorer tumor control rates than those found by clinical assessment. Symptoms were unaffected by treatment, but quality of life was improved.« less
Moyano, F Revelles; Valenza, M C; Martin, L Martin; Caballero, Y Castellote; Gonzalez-Jimenez, E; Demet, G Valenza
2013-05-01
To compare the effectiveness of proprioceptive neuromuscular facilitation combined with exercise, classic stretching physiotherapy intervention, and educational intervention at improving patient function and pain in patients with patellofemoral pain syndrome. Randomized, controlled, blind trial over four months. Urban population, Spain. Patients undergoing primary care for retropatellar pain. Subjects were allocated on three different treatment options: a proprioceptive neuromuscular facilitation and aerobic exercise group, a classic stretching group, and a control treatment were applied over four months under the supervision of a physiotherapist. Knee Society Score, pain reported (Visual analogue scale) and knee range of motion. Assessments were completed at baseline and after four months. 74 patients were enrolled in the study and distributed between groups. Both the proprioceptive neuromuscular facilitation and classic stretching group showed significant changes in all variables after four months intervention (p < 0.001). The difference in mean Kujala knee score changes between groups (classic stretching group vs. proprioceptive neuromuscular facilitation group vs. control group) at four months was -24.05 (95% confidence interval (CI) -30.19, -17.90), p ≤ 0.001; vs. -39.03 (95% confidence interval (CI) -42.5, -35.5), p ≤ 0.001; vs. -0.238 (95% confidence interval (CI) -1.2, 0.726), p = 0.621, respectively. A proprioceptive neuromuscular facilitation intervention protocol combined with aerobic exercise showed a better outcome than a classic stretching protocol after four months.
Dieting and smoking initiation in early adolescent girls and boys: a prospective study.
Austin, S B; Gortmaker, S L
2001-01-01
OBJECTIVES: This analysis tested the relation between dieting frequency and risk of smoking initiation in a longitudinal sample of adolescents. METHODS: From 1995 to 1997, 1295 middle school girls and boys participated in a nutrition and physical activity intervention study. The prospective association between dieting frequency at baseline and smoking initiation 2 years later was tested. RESULTS: Compared with girls who reported no dieting at baseline, girls who dieted up to once per week had 2 times the adjusted odds of becoming smokers (odds ratio = 2.0; 95% confidence interval = 1.1, 3.5), and girls who dieted more often had 4 times the adjusted odds of becoming smokers (odds ratio = 3.9; 95% confidence interval = 1.5, 10.4). CONCLUSIONS: Dieting among girls may exacerbate risk of initiating smoking, with increasing risk with greater dieting frequency. PMID:11236412
Mortality among three refinery/petrochemical plant cohorts. II. Retirees.
Gamble, J F; Lewis, R J; Jorgensen, G
2000-07-01
This study updates mortality data for 6238 retirees from three refinery/petrochemical plants. Almost 90% of the cohort was deceased. Deaths from all causes (standardized mortality ratio, 104; 95% confidence interval, 102 to 107) and all cancers (standardized mortality ratio, 109; 95% confidence interval, 102 to 116) were elevated. Increased deaths due to kidney cancer, mesothelioma, and the category of other lymphohemopoietic cancers also were observed. The rate of leukemia was not increased. There was little internal or external consistency to support an occupational relationship for kidney cancer, but findings for mesothelioma and other lymphohemopoietic cancers are consistent with reports for other petroleum cohorts. Analyses by age indicated significantly higher all-cause mortality rates among persons retiring before age 65. The results suggest that continued surveillance of mesothelioma and lymphohemopoietic cancer malignancies in younger workers with more contemporary exposures may be warranted. Furthermore, age at retirement should be considered when analyzing occupational cohorts.
Graff-Iversen, Sidsel; Selmer, Randi; Sørensen, Marit; Skurtveit, Svetlana
2007-06-01
This population-based 24-year follow-up study evaluated the association of occupational physical activity (OPA) with overweight and mortality in 47,405 men and women, healthy at baseline, and reporting OPA as sedentary (reference), light, moderately heavy, or heavy. The adjusted odds ratio for overweight was slightly less than 1 for all categories of current nonsedentary work in men but increased by OPA in women. Only heavy OPA conferred a lower mortality with an adjusted rate ratio of 0.84 (95 % confidence interval, 0.76-0.92) for men and 0.69 (95 % confidence interval, 0.52-0.91) for women. This observational study, with OPA recorded in the 1970s and 1980s, suggested a slight protective effect for overweight by nonsedentary work for men and lower mortality by heavy OPA for both genders.
HIV antibody seroprevalence among prisoners entering the California correctional system.
Singleton, J. A.; Perkins, C. I.; Trachtenberg, A. I.; Hughes, M. J.; Kizer, K. W.; Ascher, M.
1990-01-01
A cross-sectional blind study was conducted in the spring of 1988 to estimate the extent of human immunodeficiency virus (HIV) infection among inmates entering the California correctional system. Of the 6,834 inmates receiving entrance physical examinations during the study period, 6,179 (90.4%) had serum tested for the presence of HIV antibodies after routine blood work was completed and personal identifiers were removed. Seroprevalence was 2.5% (95% confidence interval, 2.1% to 3.0%) among the 5,372 men tested and 3.1% (95% confidence interval, 2.1% to 4.5%) among the 807 women tested. Seroprevalence was more than twice as high among men arrested in the San Francisco Bay Area as in those arrested elsewhere in the state. The regional differences in HIV seroprevalence observed among entering inmates mirror infection rates reported among intravenous drug users from the same regions. PMID:2244374
Substantiating the concept of work strain: its implication for the assessment of work stressors.
Szerencsi, Karolina; van Amelsvoort, Ludovic; Kant, Ijmert
2012-03-01
To assess which work stressors are substantially contributing to work strain and examine their relative contribution. We prospectively examined the association between work stressors and work strain, which was defined as employees reporting ill due to work stress. Relevant work stressors were combined into a stressor score with each stressor having its own relevance. Standardized odds ratios (SORs) were calculated using logistic regression analysis and used to compare the associations obtained between already existing scales and the stressor score with work strain. The stressor score yielded an SOR of 1.89 (95% confidence interval: 1.49 to 2.41) for work strain, while psychological demands (JCQ) yielded an SOR of 1.46 (95% confidence interval: 1.09 to 1.88) for work strain. We were able to extend and substantiate the range of relevant work stressors into a more comprehensive measure, which should be used to optimize prevention strategies.
Medium to long-term results of the UNIX uncemented unicompartmental knee replacement.
Hall, Matthew J; Connell, David A; Morris, Hayden G
2013-10-01
We report the first non-designer study of the Unix uncemented unicompartmental knee prosthesis. Eighty-five consecutive UKRs were carried out with sixty-five available for follow-up. Oxford Knee Scores, WOMAC questionnaire and radiological assessment were completed. The mean Oxford Knee Score was thirty-eight and WOMAC Score was twenty. Overall Kaplan Meier survival estimate is 76% (95% confidence interval 60%-97%) at 12years and 88% (95% confidence interval 76-100%) with aseptic loosening as the endpoint. Radiographic assessment showed lysis in the tibia in 6% of patients with no lysis evident around the central fin. Survivorship is comparable to other published series of UKRs. We suggest the central fin design is key to dissipating large forces throughout the proximal tibia, resulting in low levels of tibial loosening. Level of evidence IV. Copyright © 2012 Elsevier B.V. All rights reserved.
Kupersztych-Hagege, Elisa; Dubuisson, Etienne; Szekely, Barbara; Michel-Cherqui, Mireille; François Dreyfus, Jean; Fischler, Marc; Le Guen, Morgan
2017-04-01
To report the major complications (epidural hematoma and abscess) of postoperative thoracic epidural analgesia in patients who underwent lung surgery. Prospective, monocentric study. A university hospital. All lung surgical patients who received postoperative thoracic epidural analgesia between November 2007 and November 2015. Thoracic epidural analgesia for patients who underwent lung surgery. During the study period, data for 2,907 patients were recorded. The following 3 major complications were encountered: 1 case of epidural hematoma (0.34 case/1,000; 95% confidence interval 0.061-1.946), for which surgery was performed, and 2 cases of epidural abscesses (0.68 case/1,000; 95% confidence interval 0.189-2.505), which were treated medically. The risk range of serious complications was moderate; only the patient who experienced an epidural hematoma also experienced permanent sequelae. Copyright © 2017 Elsevier Inc. All rights reserved.
Asthma and school commuting time.
McConnell, Rob; Liu, Feifei; Wu, Jun; Lurmann, Fred; Peters, John; Berhane, Kiros
2010-08-01
This study examined associations of asthma with school commuting time. Time on likely school commute route was used as a proxy for on-road air pollution exposure among 4741 elementary school children at enrollment into the Children's Health Study. Lifetime asthma and severe wheeze (including multiple attacks, nocturnal, or with shortness of breath) were reported by parents. In asthmatic children, severe wheeze was associated with commuting time (odds ratio, 1.54 across the 9-minute 5% to 95% exposure distribution; 95% confidence interval, 1.01 to 2.36). The association was stronger in analysis restricted to asthmatic children with commuting times 5 minutes or longer (odds ratio, 1.97; 95% confidence interval, 1.02 to 3.77). No significant associations were observed with asthma prevalence. Among asthmatics, severe wheeze was associated with relatively short school commuting times. Further investigation of effects of on-road pollutant exposure is warranted.
Clinically significant weight gain 1 year after occupational back injury.
Keeney, Benjamin J; Fulton-Kehoe, Deborah; Wickizer, Thomas M; Turner, Judith A; Chan, Kwun Chuen Gary; Franklin, Gary M
2013-03-01
To examine the incidence of clinically significant weight gain 1 year after occupational back injury, and risk factors for that gain. A cohort of Washington State workers with wage-replacement benefits for back injuries completed baseline and 1-year follow-up telephone interviews. We obtained additional measures from claims and medical records. Among 1263 workers, 174 (13.8%) reported clinically significant weight gain (≥7%) 1 year after occupational back injury. Women and workers who had more than 180 days on wage replacement at 1 year were twice as likely (adjusted odds ratio = 2.17, 95% confidence interval = 1.54 to 3.07; adjusted odds ratio = 2.40, 95% confidence interval = 1.63 to 3.53, respectively; both P < 0.001) to have clinically significant weight gain. Women and workers on wage replacement for more than 180 days may be susceptible to clinically significant weight gain after occupational back injury.
Patil, Shantanu; McCauley, Julie C; Pulido, Pamela; Colwell, Clifford W
2015-01-01
At 14- to 17-year followup, we reported successful outcomes of the Press-fit Condylar total knee arthroplasty (TKA) system in 160 TKAs performed between 1986 and 1989. However, there are few published reports on TKA survivorship and patient function that include patients evaluated into the third decade after surgery. The study purpose was to determine (1) the survivorship of the implant; and (2) knee function in patients with this TKA system at a mean 20-year followup. We ascertained revision status of all living patients (42 of 160 knees) and all patients (22 knees) who died since the previous study. Among patients alive at the latest followup, Knee Society function scores were obtained and radiographs were evaluated. Kaplan-Meier survivorship analysis with 95% confidence intervals was performed with revision for any reason and aseptic loosening as endpoints. A competing risks analysis with 95% confidence intervals was also performed for revision for any reason as the endpoint. At the mean 20-year (range, 19-25 years) followup, all living patients retained their original implants from the index TKA, exclusive of three polyethylene exchanges. This study demonstrates an 87% Kaplan-Meier survivorship for revision for any reason (95% confidence interval [CI], 80%-92%) and a 98% Kaplan-Meier survivorship for revision for aseptic loosening (95% CI, 93%-99%). Competing risks survivorship was 79% (95% CI, 70%-85%) at 25 years for revision for any reason. Mean Knee Society function score was 46.9. Since the previous study, three revisions have been performed, all for polyethylene wear. The Press-fit Condylar implant system continues to be successful, maintaining longevity up to 25-year followup. This is one of the longest followup studies, reporting continued successes over 20 years, and should serve as a benchmark for current-generation implants. Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
Katsanos, Aristeidis H; Filippatou, Angeliki; Manios, Efstathios; Deftereos, Spyridon; Parissis, John; Frogoudaki, Alexandra; Vrettou, Agathi-Rosa; Ikonomidis, Ignatios; Pikilidou, Maria; Kargiotis, Odysseas; Voumvourakis, Konstantinos; Alexandrov, Anne W; Alexandrov, Andrei V; Tsivgoulis, Georgios
2017-01-01
Current recommendations do not specifically address the optimal blood pressure (BP) reduction for secondary stroke prevention in patients with previous cerebrovascular events. We conducted a systematic review and metaregression analysis on the association of BP reduction with recurrent stroke and cardiovascular events using data from randomized controlled clinical trials of secondary stroke prevention. For all reported events during each eligible study period, we calculated the corresponding risk ratios to express the comparison of event occurrence risk between patients randomized to antihypertensive treatment and those randomized to placebo. On the basis of the reported BP values, we performed univariate metaregression analyses according to the achieved BP values under the random-effects model (Method of Moments) for those adverse events reported in ≥10 total subgroups of included randomized controlled clinical trials. In pairwise meta-analyses, antihypertensive treatment lowered the risk for recurrent stroke (risk ratio, 0.73; 95% confidence interval, 0.62-0.87; P<0.001), disabling or fatal stroke (risk ratio, 0.71; 95% confidence interval, 0.59-0.85; P<0.001), and cardiovascular death (risk ratio, 0.85; 95% confidence interval, 0.75-0.96; P=0.01). In metaregression analyses, systolic BP reduction was linearly related to the lower risk of recurrent stroke (P=0.049), myocardial infarction (P=0.024), death from any cause (P=0.001), and cardiovascular death (P<0.001). Similarly, diastolic BP reduction was linearly related to a lower risk of recurrent stroke (P=0.026) and all-cause mortality (P=0.009). Funnel plot inspection and Egger statistical test revealed no evidence of publication bias. The extent of BP reduction is linearly associated with the magnitude of risk reduction in recurrent cerebrovascular and cardiovascular events. Strict and aggressive BP control seems to be essential for effective secondary stroke prevention. © 2016 American Heart Association, Inc.
Estimating equivalence with quantile regression
Cade, B.S.
2011-01-01
Equivalence testing and corresponding confidence interval estimates are used to provide more enlightened statistical statements about parameter estimates by relating them to intervals of effect sizes deemed to be of scientific or practical importance rather than just to an effect size of zero. Equivalence tests and confidence interval estimates are based on a null hypothesis that a parameter estimate is either outside (inequivalence hypothesis) or inside (equivalence hypothesis) an equivalence region, depending on the question of interest and assignment of risk. The former approach, often referred to as bioequivalence testing, is often used in regulatory settings because it reverses the burden of proof compared to a standard test of significance, following a precautionary principle for environmental protection. Unfortunately, many applications of equivalence testing focus on establishing average equivalence by estimating differences in means of distributions that do not have homogeneous variances. I discuss how to compare equivalence across quantiles of distributions using confidence intervals on quantile regression estimates that detect differences in heterogeneous distributions missed by focusing on means. I used one-tailed confidence intervals based on inequivalence hypotheses in a two-group treatment-control design for estimating bioequivalence of arsenic concentrations in soils at an old ammunition testing site and bioequivalence of vegetation biomass at a reclaimed mining site. Two-tailed confidence intervals based both on inequivalence and equivalence hypotheses were used to examine quantile equivalence for negligible trends over time for a continuous exponential model of amphibian abundance. ?? 2011 by the Ecological Society of America.
Sitnik, Debora; Santos, Itamar S; Goulart, Alessandra C; Staniak, Henrique L; Manson, JoAnn E; Lotufo, Paulo A; Bensenor, Isabela M
2016-11-01
We aimed to study the association between fasting plasma glucose, diabetes incidence and cardiovascular burden after 10-12 years. We evaluated diabetes and cardiovascular events incidences, carotid intima-media thickness and coronary artery calcium scores in ELSA-Brasil (the Brazilian Longitudinal Study of Adult Health) baseline (2008-2010) of 1536 adults without diabetes in 1998. We used regression models to estimate association with carotid intima-media thickness (in mm), coronary artery calcium scores (in Agatston points) and cardiovascular events according to fasting plasma glucose in 1998. Adjusted diabetes incidence rate was 9.8/1000 person-years (95% confidence interval: 7.7-13.6/1000 person-years). Incident diabetes was positively associated with higher fasting plasma glucose. Fasting plasma glucose levels 110-125 mg/dL were associated with higher carotid intima-media thickness (β = 0.028; 95% confidence interval: 0.003-0.053). Excluding those with incident diabetes, there was a borderline association between higher carotid intima-media thickness and fasting plasma glucose 110-125 mg/dL (β = 0.030; 95% confidence interval: -0.005 to 0.065). Incident diabetes was associated with higher carotid intima-media thickness (β = 0.034; 95% confidence interval: 0.015-0.053), coronary artery calcium scores ⩾400 (odds ratio = 2.84; 95% confidence interval: 1.17-6.91) and the combined outcome of a coronary artery calcium scores ⩾400 or incident cardiovascular event (odds ratio = 3.50; 95% confidence interval: 1.60-7.65). In conclusion, fasting plasma glucose in 1998 and incident diabetes were associated with higher cardiovascular burden. © The Author(s) 2016.
Prevalence of infections among residents of Residential Care Homes for the Elderly in Hong Kong.
Choy, C Sm; Chen, H; Yau, C Sw; Hsu, E K; Chik, N Y; Wong, A Ty
2016-08-01
A point prevalence study was conducted to study the epidemiology of common infections among residents in Residential Care Homes for the Elderly in Hong Kong and their associated factors. Residential Care Homes for the Elderly in Hong Kong were selected by stratified single-stage cluster random sampling. All residents aged 65 years or above from the recruited homes were surveyed. Infections were identified using standardised definitions. Demographic and health information-including medical history, immunisation record, antibiotic use, and activities of daily living (as measured by Barthel Index)-was collected by a survey team to determine any associated factors. Data were collected from 3857 residents in 46 Residential Care Homes for the Elderly from February to May 2014. A total of 105 residents had at least one type of infection based on the survey definition. The overall prevalence of all infections was 2.7% (95% confidence interval, 2.2%-3.4%). The three most common infections were of the respiratory tract (1.3%; 95% confidence interval, 0.9%-1.9%), skin and soft tissue (0.7%; 95% confidence interval, 0.5%-1.0%), and urinary tract (0.5%; 95% confidence interval, 0.3%-0.9%). Total dependence in activities of daily living, as indicated by low Barthel Index score of 0 to 20 (odds ratio=3.0; 95% confidence interval, 1.4-6.2), and presence of a wound or stoma (odds ratio=2.7; 95% confidence interval, 1.4-4.9) were significantly associated with presence of infection. This survey provides information about infections among residents in Residential Care Homes for the Elderly in the territory. Local data enable us to understand the burden of infections and formulate targeted measures for prevention.
Trotman, Carroll-Ann; Phillips, Ceib; Faraway, Julian J.; Hartman, Terry; van Aalst, John A.
2013-01-01
Objective To determine whether a systematic evaluation of facial soft tissues of patients with cleft lip and palate, using facial video images and objective three-dimensional measurements of movement, change surgeons’ treatment plans for lip revision surgery. Design Prospective longitudinal study. Setting The University of North Carolina School of Dentistry. Patients, Participants A group of patients with repaired cleft lip and palate (n = 21), a noncleft control group (n = 37), and surgeons experienced in cleft care. Interventions Lip revision. Main Outcome Measures (1) facial photographic images; (2) facial video images during animations; (3) objective three-dimensional measurements of upper lip movement based on z scores; and (4) objective dynamic and visual three-dimensional measurement of facial soft tissue movement. Results With the use of the video images plus objective three-dimensional measures, changes were made to the problem list of the surgical treatment plan for 86% of the patients (95% confidence interval, 0.64 to 0.97) and the surgical goals for 71% of the patients (95% confidence interval, 0.48 to 0.89). The surgeon group varied in the percentage of patients for whom the problem list was modified, ranging from 24% (95% confidence interval, 8% to 47%) to 48% (95% confidence interval, 26% to 70%) of patients, and the percentage for whom the surgical goals were modified, ranging from 14% (94% confidence interval, 3% to 36%) to 48% (95% confidence interval, 26% to 70%) of patients. Conclusions For all surgeons, the additional assessment components of the systematic valuation resulted in a change in clinical decision making for some patients. PMID:23855676
Lower hospital mortality and complications after pediatric hematopoietic stem cell transplantation.
Bratton, Susan L; Van Duker, Heather; Statler, Kimberly D; Pulsipher, Michael A; McArthur, Jennifer; Keenan, Heather T
2008-03-01
To assess protective and risk factors for mortality among pediatric patients during initial care after hematopoietic stem cell transplantation (HSCT) and to evaluate changes in hospital mortality. Retrospective cohort using the 1997, 2000, and 2003 Kids Inpatient Database, a probabilistic sample of children hospitalized in the United States with a procedure code for HSCT. Hospitalized patients in the United States submitted to the database. Age, <19 yrs. None. Hospital mortality significantly decreased from 12% in 1997 to 6% in 2003. Source of stem cells changed with increased use of cord blood. Rates of sepsis, graft versus host disease, and mechanical ventilation significantly decreased. Compared with autologous HSCT, patients who received an allogenic HSCT without T-cell depletion were more likely to die (adjusted odds ratio, 2.4; 95% confidence interval, 1.5, 3.9), while children who received cord blood HSCT were at the greatest risk of hospital death (adjusted odds ratio, 4.8; 95% confidence interval, 2.6, 9.1). Mechanical ventilation (adjusted odds ratio, 26.32; 95% confidence interval, 16.3-42.2), dialysis (adjusted odds ratio, 12.9; 95% confidence interval, 4.7-35.4), and sepsis (adjusted odds ratio, 3.9; 95% confidence interval, 2.5-6.1) were all independently associated with death, while care in 2003 was associated with decreased risk (adjusted odds ratio, 0.4; 95% confidence interval, 0.2-0.7) of death. Hospital mortality after HSCT in children decreased over time as did complications including need for mechanical ventilation, graft versus host disease, and sepsis. Prevention of complications is essential as the need for invasive support continues to be associated with high mortality risk.
Hashemi, Hassan; Rezvan, Farhad; Ostadimoghaddam, Hadi; Abdollahi, Majid; Hashemi, Maryam; Khabazkhoob, Mehdi
2013-01-01
The prevalence of myopia and hyperopia and determinants were determined in a rural population of Iran. Population-based cross-sectional study. Using random cluster sampling, 13 of the 83 villages of Khaf County in the north east of Iran were selected. Data from 2001 people over the age of 15 years were analysed. Visual acuity measurement, non-cycloplegic refraction and eye examinations were done at the Mobile Eye Clinic. The prevalence of myopia and hyperopia based on spherical equivalent worse than -0.5 dioptre and +0.5 dioptre, respectively. The prevalence of myopia, hyperopia and anisometropia in the total study sample was 28% (95% confidence interval: 25.9-30.2), 19.2% (95% confidence interval: 17.3-21.1), and 11.5% (95% confidence interval: 10.0-13.1), respectively. In the over 40 population, the prevalence of myopia and hyperopia was 32.5% (95% confidence interval: 28.9-36.1) and 27.9% (95% confidence interval: 24.5-31.3), respectively. In the multiple regression model for this group, myopia strongly correlated with cataract (odds ratio = 1.98 and 95% confidence interval: 1.33-2.93), and hyperopia only correlated with age (P < 0.001). The prevalence of high myopia and high hyperopia was 1.5% and 4.6%. In the multiple regression model, anisometropia significantly correlated with age (odds ratio = 1.04) and cataract (odds ratio = 5.2) (P < 0.001). The prevalence of myopia and anisometropia was higher than that in previous studies in urban population of Iran, especially in the elderly. Cataract was the only variable that correlated with myopia and anisometropia. © 2013 The Authors. Clinical and Experimental Ophthalmology © 2013 Royal Australian and New Zealand College of Ophthalmologists.
The Association Between Maternal Age and Cerebral Palsy Risk Factors.
Schneider, Rilla E; Ng, Pamela; Zhang, Xun; Andersen, John; Buckley, David; Fehlings, Darcy; Kirton, Adam; Wood, Ellen; van Rensburg, Esias; Shevell, Michael I; Oskoui, Maryam
2018-05-01
Advanced maternal age is associated with higher frequencies of antenatal and perinatal conditions, as well as a higher risk of cerebral palsy in offspring. We explore the association between maternal age and specific cerebral palsy risk factors. Data were extracted from the Canadian Cerebral Palsy Registry. Maternal age was categorized as ≥35 years of age and less than 20 years of age at the time of birth. Chi-square and multivariate logistic regressions were performed to calculate odds ratios and their 95% confidence intervals. The final sample consisted of 1391 children with cerebral palsy, with 19% of children having mothers aged 35 or older and 4% of children having mothers below the age of 20. Univariate analyses showed that mothers aged 35 or older were more likely to have gestational diabetes (odds ratio 1.9, 95% confidence interval 1.3 to 2.8), to have a history of miscarriage (odds ratio 1.8, 95% confidence interval 1.3 to 2.4), to have undergone fertility treatments (odds ratio 2.4, 95% confidence interval 1.5 to 3.9), and to have delivered by Caesarean section (odds ratio 1.6, 95% confidence interval 1.2 to 2.2). These findings were supported by multivariate analyses. Children with mothers below the age of 20 were more likely to have a congenital malformation (odds ratio 2.4, 95% confidence interval 1.4 to 4.2), which is also supported by multivariate analysis. The risk factor profiles of children with cerebral palsy vary by maternal age. Future studies are warranted to further our understanding of the compound causal pathways leading to cerebral palsy and the observed greater prevalence of cerebral palsy with increasing maternal age. Copyright © 2018 Elsevier Inc. All rights reserved.
Higginson, Irene J; Gomes, Barbara; Calanzani, Natalia; Gao, Wei; Bausewein, Claudia; Daveson, Barbara A; Deliens, Luc; Ferreira, Pedro L; Toscani, Franco; Gysels, Marjolein; Ceulemans, Lucas; Simon, Steffen T; Cohen, Joachim; Harding, Richard
2014-02-01
Health-care costs are growing, with little population-based data about people's priorities for end-of-life care, to guide service development and aid discussions. We examined variations in people's priorities for treatment, care and information across seven European countries. Telephone survey of a random sample of households; we asked respondents their priorities if 'faced with a serious illness, like cancer, with limited time to live' and used multivariable logistic regressions to identify associated factors. Members of the general public aged ≥ 16 years residing in England, Flanders, Germany, Italy, the Netherlands, Portugal and Spain. In total, 9344 individuals were interviewed. Most people chose 'improve quality of life for the time they had left', ranging from 57% (95% confidence interval: 55%-60%, Italy) to 81% (95% confidence interval: 79%-83%, Spain). Only 2% (95% confidence interval: 1%-3%, England) to 6% (95% confidence interval: 4%-7%, Flanders) said extending life was most important, and 15% (95% confidence interval: 13%-17%, Spain) to 40% (95% confidence interval: 37%-43%, Italy) said quality and extension were equally important. Prioritising quality of life was associated with higher education in all countries (odds ratio = 1.3 (Flanders) to 7.9 (Italy)), experience of caregiving or bereavement (England, Germany, Portugal), prioritising pain/symptom control over having a positive attitude and preferring death in a hospice/palliative care unit. Those prioritising extending life had the highest home death preference of all groups. Health status did not affect priorities. Across all countries, extending life was prioritised by a minority, regardless of health status. Treatment and care needs to be reoriented with patient education and palliative care becoming mainstream for serious conditions such as cancer.
Kaiser, Reinhard; Romieu, Isabelle; Medina, Sylvia; Schwartz, Joel; Krzyzanowski, Michal; Künzli, Nino
2004-01-01
Background The impact of outdoor air pollution on infant mortality has not been quantified. Methods Based on exposure-response functions from a U.S. cohort study, we assessed the attributable risk of postneonatal infant mortality in 23 U.S. metropolitan areas related to particulate matter <10 μm in diameter (PM10) as a surrogate of total air pollution. Results The estimated proportion of all cause mortality, sudden infant death syndrome (normal birth weight infants only) and respiratory disease mortality (normal birth weight) attributable to PM10 above a chosen reference value of 12.0 μg/m3 PM10 was 6% (95% confidence interval 3–11%), 16% (95% confidence interval 9–23%) and 24% (95% confidence interval 7–44%), respectively. The expected number of infant deaths per year in the selected areas was 106 (95% confidence interval 53–185), 79 (95% confidence interval 46–111) and 15 (95% confidence interval 5–27), respectively. Approximately 75% of cases were from areas where the current levels are at or below the new U.S. PM2.5 standard of 15 μg/m3 (equivalent to 25 μg/m3 PM10). In a country where infant mortality rates and air pollution levels are relatively low, ambient air pollution as measured by particulate matter contributes to a substantial fraction of infant death, especially for those due to sudden infant death syndrome and respiratory disease. Even if all counties would comply to the new PM2.5 standard, the majority of the estimated burden would remain. Conclusion Given the inherent limitations of risk assessments, further studies are needed to support and quantify the relationship between infant mortality and air pollution. PMID:15128459
Fung, Tak; Keenan, Kevin
2014-01-01
The estimation of population allele frequencies using sample data forms a central component of studies in population genetics. These estimates can be used to test hypotheses on the evolutionary processes governing changes in genetic variation among populations. However, existing studies frequently do not account for sampling uncertainty in these estimates, thus compromising their utility. Incorporation of this uncertainty has been hindered by the lack of a method for constructing confidence intervals containing the population allele frequencies, for the general case of sampling from a finite diploid population of any size. In this study, we address this important knowledge gap by presenting a rigorous mathematical method to construct such confidence intervals. For a range of scenarios, the method is used to demonstrate that for a particular allele, in order to obtain accurate estimates within 0.05 of the population allele frequency with high probability (> or = 95%), a sample size of > 30 is often required. This analysis is augmented by an application of the method to empirical sample allele frequency data for two populations of the checkerspot butterfly (Melitaea cinxia L.), occupying meadows in Finland. For each population, the method is used to derive > or = 98.3% confidence intervals for the population frequencies of three alleles. These intervals are then used to construct two joint > or = 95% confidence regions, one for the set of three frequencies for each population. These regions are then used to derive a > or = 95%% confidence interval for Jost's D, a measure of genetic differentiation between the two populations. Overall, the results demonstrate the practical utility of the method with respect to informing sampling design and accounting for sampling uncertainty in studies of population genetics, important for scientific hypothesis-testing and also for risk-based natural resource management.
Darney, Blair G; Saavedra-Avendano, Biani; Sosa-Rubi, Sandra G; Lozano, Rafael; Rodriguez, Maria I
2016-07-01
Associations between age and patient-reported quality of family planning services were examined among young women in Mexico. A repeated cross-sectional analysis of survey data collected in 2006, 2009, and 2014 was performed. Data from women aged 15-29years who had not undergone sterilization and were currently using a modern contraceptive method were included. The primary outcome was high-quality care, defined as positive responses to all five quality items regarding contraceptive services included in the survey. Multivariable logistic regression and marginal probabilities were used to compare adolescents and women aged 20-29years. The responses of respondents using different contraceptive methods were compared. Data were included from 15 835 individuals. The multivariable analysis demonstrated lower odds of reporting high-quality care among women aged 15-19years (odds ratio 0.73; 95% confidence interval 0.60-0.88) and 20-24years (odds ratio 0.85; 95% confidence interval 0.75-0.96) compared with women aged 25-29years. Adolescents using hormonal and long-acting reversible contraception had significantly lower odds of reporting high-quality care compared with women aged 25-29. Adolescents in Mexico reported a lower quality of family planning services compared with young adult women. Continued research and policies are needed to improve the quality of contraceptive services. Copyright © 2016 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.
Daerga, Laila; Sjölander, Per; Jacobsson, Lars; Edin-Liljegren, Anette
2012-08-01
To investigate the confidence in primary health care, psychiatry and social services among the reindeer-herding Sami and the non-Sami population of northern Sweden. A semi-randomized, cross-sectional study design comprising 325 reindeer-herding Sami (171 men, 154 women) and a control population of 1,437 non-Sami (684 men, 753 women). A questionnaire on the confidence in primary health care, psychiatry, social services, and work colleagues was distributed to members of reindeer-herding families through the Sami communities and to the control population through the post. The relative risk for poor confidence was analyzed by calculating odds ratios with 95% confidence intervals adjusted for age and level of education. The confidence in primary health care and psychiatry was significantly lower among the reindeer-herding Sami compared with the control group. No differences were found between men and women in the reindeer-herding Sami population. In both the reindeer-herding Sami and the control population, younger people (≤ 48 years) reported significantly lower confidence in primary health care than older individuals (>48 years). A conceivable reason for the poor confidence in health care organizations reported by the reindeer-herding Sami is that they experience health care staff as poorly informed about reindeer husbandry and Sami culture, resulting in unsuitable or unrealistic treatment suggestions. The findings suggest that the poor confidence constitutes a significant obstacle of the reindeer-herding Sami to fully benefit from public health care services.
Four Bootstrap Confidence Intervals for the Binomial-Error Model.
ERIC Educational Resources Information Center
Lin, Miao-Hsiang; Hsiung, Chao A.
1992-01-01
Four bootstrap methods are identified for constructing confidence intervals for the binomial-error model. The extent to which similar results are obtained and the theoretical foundation of each method and its relevance and ranges of modeling the true score uncertainty are discussed. (SLD)
Teach a Confidence Interval for the Median in the First Statistics Course
ERIC Educational Resources Information Center
Howington, Eric B.
2017-01-01
Few introductory statistics courses consider statistical inference for the median. This article argues in favour of adding a confidence interval for the median to the first statistics course. Several methods suitable for introductory statistics students are identified and briefly reviewed.
Dyke, Peter C; Yates, Andrew R; Cua, Clifford L; Hoffman, Timothy M; Hayes, John; Feltes, Timothy F; Springer, Michelle A; Taeed, Roozbeh
2007-05-01
The purpose of this study was to assess the association of calcium replacement therapy with morbidity and mortality in infants after cardiac surgery involving cardiopulmonary bypass. Retrospective chart review. The cardiac intensive care unit at a tertiary care children's hospital. Infants undergoing cardiac surgery involving cardiopulmonary bypass between October 2002 and August 2004. None. Total calcium replacement (mg/kg calcium chloride given) for the first 72 postoperative hours was measured. Morbidity and mortality data were collected. The total volume of blood products given during the first 72 hrs was recorded. Infants with confirmed chromosomal deletions at the 22q11 locus were noted. Correlation and logistic regression analyses were used to generate odds ratios and 95% confidence intervals, with p < .05 being significant. One hundred seventy-one infants met inclusion criteria. Age was 4 +/- 3 months and weight was 4.9 +/- 1.7 kg at surgery. Six infants had deletions of chromosome 22q11. Infants who weighed less required more calcium replacement (r = -.28, p < .001). Greater calcium replacement correlated with a longer intensive care unit length of stay (r = .27, p < .001) and a longer total hospital length of stay (r = .23, p = .002). Greater calcium replacement was significantly associated with morbidity (liver dysfunction [odds ratio, 3.9; confidence interval, 2.1-7.3; p < .001], central nervous system complication [odds ratio, 1.8; confidence interval, 1.1-3.0; p = .02], infection [odds ratio, 1.5; confidence interval, 1.0-2.2; p < .04], extracorporeal membrane oxygenation [odds ratio, 5.0; confidence interval, 2.3-10.6; p < .001]) and mortality (odds ratio, 5.8; confidence interval, 5.8-5.9; p < .001). Greater calcium replacement was not associated with renal insufficiency (odds ratio, 1.5; confidence interval, 0.9-2.3; p = .07). Infants with >1 sd above the mean of total calcium replacement received on average fewer blood products than the total study population. Greater calcium replacement is associated with increasing morbidity and mortality. Further investigation of the etiology and therapy of hypocalcemia in this population is warranted.
Pihlajamäki, Harri K; Kuikka, Paavo-Ilari; Leppänen, Vesa-Veikko; Kiuru, Martti J; Mattila, Ville M
2010-04-01
This diagnostic study was performed to determine the correlation between anterior knee pain and chondromalacia patellae and to define the reliability of magnetic resonance imaging for the diagnosis of chondromalacia patellae. Fifty-six young adults (median age, 19.5 years) with anterior knee pain had magnetic resonance imaging of the knee followed by arthroscopy. The patellar chondral lesions identified by magnetic resonance imaging were compared with the arthroscopic findings. Arthroscopy confirmed the presence of chondromalacia patellae in twenty-five (45%) of the fifty-six knees, a synovial plica in twenty-five knees, a meniscal tear in four knees, and a femorotibial chondral lesion in four knees; normal anatomy was seen in six knees. No association was found between the severity of the chondromalacia patellae seen at arthroscopy and the clinical symptoms of anterior knee pain syndrome (p = 0.83). The positive predictive value for the ability of 1.0-T magnetic resonance imaging to detect chondromalacia patellae was 75% (95% confidence interval, 53% to 89%), the negative predictive value was 72% (95% confidence interval, 56% to 84%), the sensitivity was 60% (95% confidence interval, 41% to 77%), the specificity was 84% (95% confidence interval, 67% to 93%), and the diagnostic accuracy was 73% (95% confidence interval, 60% to 83%). The sensitivity was 13% (95% confidence interval, 2% to 49%) for grade-I lesions and 83% (95% confidence interval, 59% to 94%) for grade-II, III, or IV lesions. Chondromalacia patellae cannot be diagnosed on the basis of symptoms or with current physical examination methods. The present study demonstrated no correlation between the severity of chondromalacia patellae and the clinical symptoms of anterior knee pain syndrome. Thus, symptoms of anterior knee pain syndrome should not be used as an indication for knee arthroscopy. The sensitivity of 1.0-T magnetic resonance imaging was low for grade-I lesions but considerably higher for more severe (grade-II, III, or IV) lesions. Magnetic resonance imaging may be considered an accurate diagnostic tool for identification of more severe cases of chondromalacia patellae.
Pérez de Prado, Armando; López-Gómez, Juan M.; Quiroga, Borja; Goicoechea, Marian; García-Prieto, Ana; Torres, Esther; Reque, Javier; Luño, José
2016-01-01
Background and objectives Supraventricular arrhythmias are associated with high morbidity and mortality. Nevertheless, this condition has received little attention in patients on hemodialysis. The objective of this study was to analyze the incidence of intradialysis supraventricular arrhythmia and its long–term prognostic value. Design, setting, participants, & measurements We designed an observational and prospective study in a cohort of patients on hemodialysis with a 10-year follow-up period. All patients were recruited for study participation and were not recruited for clinical indications. The study population comprised 77 patients (42 men and 35 women; mean age =58±15 years old) with sinus rhythm monitored using a Holter electrocardiogram over six consecutive hemodialysis sessions at recruitment. Results Hypertension was present in 68.8% of patients, and diabetes was present in 29.9% of patients. Supraventricular arrhythmias were recorded in 38 patients (49.3%); all of these were short, asymptomatic, and self-limiting. Age (hazard ratio, 1.04 per year; 95% confidence interval, 1.00 to 1.08) and right atrial enlargement (hazard ratio, 4.29; 95% confidence interval, 1.30 to 14.09) were associated with supraventricular arrhythmia in the multivariate analysis. During a median follow-up of 40 months, 57 patients died, and cardiovascular disease was the main cause of death (52.6%). The variables associated with all-cause mortality in the Cox model were age (hazard ratio, 1.04 per year; 95% confidence interval, 1.00 to 1.08), C-reactive protein (hazard ratio, 1.04 per 1 mg/L; 95% confidence interval, 1.00 to 1.08), and supraventricular arrhythmia (hazard ratio, 3.21; 95% confidence interval, 1.29 to 7.96). Patients with supraventricular arrhythmia also had a higher risk of nonfatal cardiovascular events (hazard ratio, 4.32; 95% confidence interval, 2.11 to 8.83) and symptomatic atrial fibrillation during follow-up (hazard ratio, 17.19; 95% confidence interval, 2.03 to 145.15). Conclusions The incidence of intradialysis supraventricular arrhythmia was high in our hemodialysis study population. Supraventricular arrhythmias were short, asymptomatic, and self-limiting, and although silent, these arrhythmias were independently associated with mortality and cardiovascular events. PMID:27697781
Verde, Eduardo; Pérez de Prado, Armando; López-Gómez, Juan M; Quiroga, Borja; Goicoechea, Marian; García-Prieto, Ana; Torres, Esther; Reque, Javier; Luño, José
2016-12-07
Supraventricular arrhythmias are associated with high morbidity and mortality. Nevertheless, this condition has received little attention in patients on hemodialysis. The objective of this study was to analyze the incidence of intradialysis supraventricular arrhythmia and its long-term prognostic value. We designed an observational and prospective study in a cohort of patients on hemodialysis with a 10-year follow-up period. All patients were recruited for study participation and were not recruited for clinical indications. The study population comprised 77 patients (42 men and 35 women; mean age =58±15 years old) with sinus rhythm monitored using a Holter electrocardiogram over six consecutive hemodialysis sessions at recruitment. Hypertension was present in 68.8% of patients, and diabetes was present in 29.9% of patients. Supraventricular arrhythmias were recorded in 38 patients (49.3%); all of these were short, asymptomatic, and self-limiting. Age (hazard ratio, 1.04 per year; 95% confidence interval, 1.00 to 1.08) and right atrial enlargement (hazard ratio, 4.29; 95% confidence interval, 1.30 to 14.09) were associated with supraventricular arrhythmia in the multivariate analysis. During a median follow-up of 40 months, 57 patients died, and cardiovascular disease was the main cause of death (52.6%). The variables associated with all-cause mortality in the Cox model were age (hazard ratio, 1.04 per year; 95% confidence interval, 1.00 to 1.08), C-reactive protein (hazard ratio, 1.04 per 1 mg/L; 95% confidence interval, 1.00 to 1.08), and supraventricular arrhythmia (hazard ratio, 3.21; 95% confidence interval, 1.29 to 7.96). Patients with supraventricular arrhythmia also had a higher risk of nonfatal cardiovascular events (hazard ratio, 4.32; 95% confidence interval, 2.11 to 8.83) and symptomatic atrial fibrillation during follow-up (hazard ratio, 17.19; 95% confidence interval, 2.03 to 145.15). The incidence of intradialysis supraventricular arrhythmia was high in our hemodialysis study population. Supraventricular arrhythmias were short, asymptomatic, and self-limiting, and although silent, these arrhythmias were independently associated with mortality and cardiovascular events. Copyright © 2016 by the American Society of Nephrology.
Long-term Results of an Obesity Program in an Ethnically Diverse Pediatric Population
Nowicka, Paulina; Shaw, Melissa; Yu, Sunkyung; Dziura, James; Chavent, Georgia; O'Malley, Grace; Serrecchia, John B.; Tamborlane, William V.; Caprio, Sonia
2011-01-01
OBJECTIVE: To determine if beneficial effects of a weight-management program could be sustained for up to 24 months in a randomized trial in an ethnically diverse obese population. PATIENTS AND METHODS: There were 209 obese children (BMI > 95th percentile), ages 8 to 16 of mixed ethnic backgrounds randomly assigned to the intensive lifestyle intervention or clinic control group. The control group received counseling every 6 months, and the intervention group received a family-based program, which included exercise, nutrition, and behavior modification. Lifestyle intervention sessions occurred twice weekly for the first 6 months, then twice monthly for the second 6 months; for the last 12 months there was no active intervention. There were 174 children who completed the 12 months of the randomized trial. Follow-up data were available for 76 of these children at 24 months. There were no statistical differences in dropout rates among ethnic groups or in any other aspects. RESULTS: Treatment effect was sustained at 24 months in the intervention versus control group for BMI z score (−0.16 [95% confidence interval: −0.23 to −0.09]), BMI (−2.8 kg/m2 [95% confidence interval: −4.0–1.6 kg/m2]), percent body fat (−4.2% [95% confidence interval: −6.4% to −2.0%]), total body fat mass (−5.8 kg [95% confidence interval: −9.1 kg to −2.6 kg]), total cholesterol (−13.0 mg/dL [95% confidence interval: −21.7 mg/dL to −4.2 mg/dL]), low-density lipoprotein cholesterol (−10.4 mg/dL [95% confidence interval: −18.3 mg/dL to −2.4 mg/dL]), and homeostasis model assessment of insulin resistance (−2.05 [95% confidence interval: −2.48 to −1.75]). CONCLUSIONS: This study, unprecedented because of the high degree of obesity and ethnically diverse backgrounds of children, reveals that benefits of an intensive lifestyle program can be sustained 12 months after completing the active intervention phase. PMID:21300674
Elevated lung cancer in younger adults and low concentrations of arsenic in water.
Steinmaus, Craig; Ferreccio, Catterina; Yuan, Yan; Acevedo, Johanna; González, Francisca; Perez, Liliana; Cortés, Sandra; Balmes, John R; Liaw, Jane; Smith, Allan H
2014-12-01
Arsenic concentrations greater than 100 µg/L in drinking water are a known cause of cancer, but the risks associated with lower concentrations are less well understood. The unusual geology and good information on past exposure found in northern Chile are key advantages for investigating the potential long-term effects of arsenic. We performed a case-control study of lung cancer from 2007 to 2010 in areas of northern Chile that had a wide range of arsenic concentrations in drinking water. Previously, we reported evidence of elevated cancer risks at arsenic concentrations greater than 100 µg/L. In the present study, we restricted analyses to the 92 cases and 288 population-based controls who were exposed to concentrations less than 100 µg/L. After adjustment for age, sex, and smoking behavior, these exposures from 40 or more years ago resulted in odds ratios for lung cancer of 1.00, 1.43 (90% confidence interval: 0.82, 2.52), and 2.01 (90% confidence interval: 1.14, 3.52) for increasing tertiles of arsenic exposure, respectively (P for trend = 0.02). Mean arsenic water concentrations in these tertiles were 6.5, 23.0, and 58.6 µg/L. For subjects younger than 65 years of age, the corresponding odds ratios were 1.00, 1.62 (90% confidence interval: 0.67, 3.90), and 3.41 (90% confidence interval: 1.51, 7.70). Adjustments for occupation, fruit and vegetable intake, and socioeconomic status had little impact on the results. These findings provide new evidence that arsenic water concentrations less than 100 µg/L are associated with higher risks of lung cancer. © The Author 2014. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Coulombe, Janie; Li, Linxin; Ganesh, Aravind; Silver, Louise; Rothwell, Peter M.
2017-01-01
Background and Purpose— Several studies have reported unexplained worse outcomes after stroke in women but none included the full spectrum of symptomatic ischemic cerebrovascular events while adjusting for prior handicap. Methods— Using a prospective population-based incident cohort of all transient ischemic attack/stroke (OXVASC [Oxford Vascular Study]) recruited between April 2002 and March 2014, we compared pre-morbid and post-event modified Rankin Scale score (mRS) in women and men and change in mRS score 1 month, 6 months, 1 year, and 5 years after stroke. Baseline stroke-related neurological impairment was measured with the National Institutes of Health Stroke Scale. Results— Among 2553 patients (50.6% women) with a first transient ischemic attack/ischemic stroke, women had a worse handicap 1 month after ischemic stroke (age-adjusted odds ratio for mRS score, 1.35; 95% confidence interval, 1.12–1.63). However, women also had a higher pre-morbid mRS score compared with men (age-adjusted odds ratio, 1.58; 95% confidence interval, 1.36–1.84). There was no difference in stroke severity when adjusting for age and pre-morbid mRS (odds ratio, 1.10; 95% confidence interval, 0.90–1.35) and no difference in the pre-/poststroke change in mRS at 1 month (age-adjusted odds ratio, 1.00; 95% confidence interval, 0.82–1.21), 6 months, 1 year, and 5 years. Women had a lower mortality rate, and there was no sex difference in risk of recurrent stroke. Conclusions— We found no evidence of a worse outcome of stroke in women when adjusting for age and pre-morbid mRS. Failure to account for sex differences in pre-morbid handicap could explain contradictory findings in previous studies. Properties of the mRS may also contribute to these inconsistencies. PMID:28798261
Renoux, Christel; Coulombe, Janie; Li, Linxin; Ganesh, Aravind; Silver, Louise; Rothwell, Peter M
2017-10-01
Several studies have reported unexplained worse outcomes after stroke in women but none included the full spectrum of symptomatic ischemic cerebrovascular events while adjusting for prior handicap. Using a prospective population-based incident cohort of all transient ischemic attack/stroke (OXVASC [Oxford Vascular Study]) recruited between April 2002 and March 2014, we compared pre-morbid and post-event modified Rankin Scale score (mRS) in women and men and change in mRS score 1 month, 6 months, 1 year, and 5 years after stroke. Baseline stroke-related neurological impairment was measured with the National Institutes of Health Stroke Scale. Among 2553 patients (50.6% women) with a first transient ischemic attack/ischemic stroke, women had a worse handicap 1 month after ischemic stroke (age-adjusted odds ratio for mRS score, 1.35; 95% confidence interval, 1.12-1.63). However, women also had a higher pre-morbid mRS score compared with men (age-adjusted odds ratio, 1.58; 95% confidence interval, 1.36-1.84). There was no difference in stroke severity when adjusting for age and pre-morbid mRS (odds ratio, 1.10; 95% confidence interval, 0.90-1.35) and no difference in the pre-/poststroke change in mRS at 1 month (age-adjusted odds ratio, 1.00; 95% confidence interval, 0.82-1.21), 6 months, 1 year, and 5 years. Women had a lower mortality rate, and there was no sex difference in risk of recurrent stroke. We found no evidence of a worse outcome of stroke in women when adjusting for age and pre-morbid mRS. Failure to account for sex differences in pre-morbid handicap could explain contradictory findings in previous studies. Properties of the mRS may also contribute to these inconsistencies. Copyright © 2017 The Author(s).
Bai, Ying; Deng, Hai; Shantsila, Alena; Lip, Gregory Y H
2017-04-01
This study was designed to evaluate the effectiveness and safety of rivaroxaban in real-world practice compared with effectiveness and safety of dabigatran or warfarin for stroke prevention in atrial fibrillation through meta-analyzing observational studies. Seventeen studies were included after searching in PubMed for studies reporting the comparative effectiveness and safety of rivaroxaban versus dabigatran (n=3), rivaroxaban versus Warfarin (n=11), or both (n=3) for stroke prevention in atrial fibrillation. Overall, the risks of stroke/systematic thromboembolism with rivaroxaban were similar when compared with those with dabigatran (stroke/thromboembolism: hazard ratio, 1.02; 95% confidence interval, 0.91-1.13; I 2 =70.2%, N=5), but were significantly reduced when compared with those with warfarin (hazard ratio, 0.75; 95% confidence interval, 0.64-0.85; I 2 =45.1%, N=9). Major bleeding risk was significantly higher with rivaroxaban than with dabigatran (hazard ratio, 1.38; 95% confidence interval, 1.27-1.49; I 2 =26.1%, N=5), but similar to that with warfarin (hazard ratio, 0.99; 95% confidence interval, 0.91-1.07; I 2 =0.0%, N=6). Rivaroxaban was associated with increased all-cause mortality and gastrointestinal bleeding, but similar risk of acute myocardial infarction and intracranial hemorrhage when compared with dabigatran. When compared with warfarin, rivaroxaban was associated with similar risk of any bleeding, mortality, and acute myocardial infarction, but a higher risk of gastrointestinal bleeding and lower risk of intracranial hemorrhage. In this systematic review and meta-analysis, rivaroxaban was as effective as dabigatran, but was more effective than warfarin for the prevention of stroke/thromboembolism in atrial fibrillation patients. Major bleeding risk was significantly higher with rivaroxaban than with dabigatran, as was all-cause mortality and gastrointestinal bleeding. Rivaroxaban was comparable to warfarin for major bleeding, with an increased risk in gastrointestinal bleeding and decreased risk of intracranial hemorrhage. © 2017 American Heart Association, Inc.
Whitson, Bryan A; Groth, Shawn S; Andrade, Rafael S; Mitiek, Mohi O; Maddaus, Michael A; D'Cunha, Jonathan
2012-03-01
We used a population-based data set to assess the association between the extent of pulmonary resection for bronchoalveolar carcinoma and survival. The reports thus far have been limited to small, institutional series. Using the Surveillance, Epidemiology, and End Results database (1988-2007), we identified patients with bronchoalveolar carcinoma who had undergone wedge resection, segmentectomy, or lobectomy. The bronchoalveolar carcinoma histologic findings were mucinous, nonmucinous, mixed, not otherwise specified, and alveolar carcinoma. To adjust for potential confounders, we used a Cox proportional hazards regression model. A total of 6810 patients met the inclusion criteria. Compared with the sublobar resections (wedge resections and segmentectomies), lobectomy conferred superior 5-year overall (59.5% vs 43.9%) and cancer-specific (67.1% vs 53.1%) survival (P < .0001). After adjusting for potential confounding patient and tumor characteristics, we found that patients who underwent an anatomic resection had significantly better overall (segmentectomy: hazard ratio, 0.59; 95% confidence interval, 0.43-0.81; lobectomy: hazard ratio, 0.50; 95% confidence interval, 0.44-0.57) and cancer-specific (segmentectomy: hazard ratio, 0.51; 95% confidence interval, 0.34-0.75; lobectomy: hazard ratio, 0.46; 95% confidence interval, 0.40-0.53) survival compared with patients who underwent wedge resection. Additionally, gender, race, tumor size, and degree of tumor de-differentiation were negative prognostic factors. Our results were unchanged when we limited our analysis to early-stage disease. Using a population-based data set, we found that anatomic resections for bronchoalveolar carcinoma conferred superior overall and cancer-specific survival rates compared with wedge resection. Bronchoalveolar carcinoma's propensity for intraparenchymal spread might be the underlying biologic basis of our observation of improved survival after anatomic resection. Copyright © 2012 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.
Gupta, Tanush; Kolte, Dhaval; Khera, Sahil; Agarwal, Nayan; Villablanca, Pedro A; Goel, Kashish; Patel, Kavisha; Aronow, Wilbert S; Wiley, Jose; Bortnick, Anna E; Aronow, Herbert D; Abbott, J Dawn; Pyo, Robert T; Panza, Julio A; Menegus, Mark A; Rihal, Charanjit S; Fonarow, Gregg C; Garcia, Mario J; Bhatt, Deepak L
2018-01-01
Prior studies have reported higher inhospital mortality in women versus men with non-ST-segment-elevation myocardial infarction. Whether this is because of worse baseline risk profile compared with men or sex-based disparities in treatment is not completely understood. We queried the 2003 to 2014 National Inpatient Sample databases to identify all hospitalizations in patients aged ≥18 years with the principal diagnosis of non-ST-segment-elevation myocardial infarction. Complex samples multivariable logistic regression models were used to examine sex differences in use of an early invasive strategy and inhospital mortality. Of 4 765 739 patients with non-ST-segment-elevation myocardial infarction, 2 026 285 (42.5%) were women. Women were on average 6 years older than men and had a higher comorbidity burden. Women were less likely to be treated with an early invasive strategy (29.4% versus 39.2%; adjusted odds ratio, 0.92; 95% confidence interval, 0.91-0.94). Women had higher crude inhospital mortality than men (4.7% versus 3.9%; unadjusted odds ratio, 1.22; 95% confidence interval, 1.20-1.25). After adjustment for age (adjusted odds ratio, 0.96; 95% confidence interval, 0.94-0.98) and additionally for comorbidities, other demographics, and hospital characteristics, women had 10% lower odds of inhospital mortality (adjusted odds ratio, 0.90; 95% confidence interval, 0.89-0.92). Further adjustment for differences in the use of an early invasive strategy did not change the association between female sex and lower risk-adjusted inhospital mortality. Although women were less likely to be treated with an early invasive strategy compared with men, the lower use of an early invasive strategy was not responsible for the higher crude inhospital mortality in women, which could be entirely explained by older age and higher comorbidity burden. © 2018 American Heart Association, Inc.
Heesen, Michael; Böhmer, Johannes; Klöhr, Sven; Hofmann, Thomas; Rossaint, Rolf; Straube, Sebastian
2015-07-01
Patient-controlled epidural analgesia (PCEA) has gained popularity, but it is still unclear whether adding a background infusion confers any benefit. A systematic literature search in PubMed, Embase, CINAHL, LILACS, CENTRAL, Clinicaltrials.gov, and ISI WOS was performed to identify randomized controlled double-blind trials that compare PCEA-only with PCEA combined with a continuous infusion (PCEA + CI) in parturients. The data were subjected to meta-analyses using the random-effects model. Our primary outcome was the incidence of instrumental vaginal delivery. Secondary outcomes were incidences of spontaneous vaginal and cesarean deliveries, duration of labor, analgesic outcomes, maternal outcomes (visual analog scale scores for pain, maternal satisfaction, nausea, pruritus, hypotension), and neonatal outcomes (Apgar score, umbilical artery pH). We identified 7 trials with a low risk of bias, reporting on 891 parturients, for inclusion in our systematic review. The risk of instrumental vaginal delivery was increased in the PCEA + CI group, risk ratio (RR) 1.66 (95% confidence interval 1.08-2.56, P = 0.02; I = 0%); the RR for cesarean delivery was 0.83 (95% confidence interval 0.61-1.13, I = 0%). The second stage of labor was prolonged (weighted mean difference 12.3 minutes, 95% confidence interval 5.1-19.5 minutes, P = 0.0008; I = 0%) in the PCEA + CI group. Fewer patients in the PCEA + CI group required physician-administered boluses (RR 0.35 [95% confidence interval 0.25-0.47, P < 0.00001; I = 0%]). No differences regarding maternal adverse events (nausea, pruritus, hypotension) or neonatal outcomes (Apgar scores <7, umbilical artery pH) were observed. On the basis of current evidence, no conclusion can be drawn regarding the risks or benefits of adding a continuous background infusion to PCEA compared with PCEA-only epidural labor analgesia. Further high-quality studies involving a sufficient number of patients are required.
Danchin, Nicolas; Cucherat, Michel; Thuillez, Christian; Durand, Eric; Kadri, Zena; Steg, Philippe G
2006-04-10
Results of randomized trials of angiotensin-converting enzyme inhibitors in patients with coronary artery disease (CAD) and preserved left ventricular function are conflicting. We undertook this study to determine whether long-term prescription of angiotensin-converting enzyme inhibitors decreases major cardiovascular events and mortality in patients who have CAD and no evidence of left ventricular systolic dysfunction. We searched MEDLINE, EMBASE, and IPA databases, the Cochrane Controlled Trials Register (1990-2004), and reports from scientific meetings (2003-2004), and we reviewed secondary sources. Search terms included angiotensin-converting enzyme inhibitors, coronary artery disease, randomi(s)zed controlled trials, clinical trials, and myocardial infarction. Eligible studies included randomized controlled trials in patients who had CAD and no heart failure or left ventricular dysfunction, with follow-up omicronf 2 years or longer. Of 1146 publications screened, 7 met our selection criteria and included a total of 33 960 patients followed up for a mean of 4.4 years. Five trials included only patients with documented CAD. One trial included patients with documented CAD (80%) or patients who had diabetes mellitus and 1 or more additional risk factors, and another trial included patients who had CAD, a history of transient ischemic attack, or intermittent claudication. Treatment with angiotensin-converting enzyme inhibitors decreased overall mortality (odds ratio, 0.86; 95% confidence interval, 0.79-0.93), cardiovascular mortality (odds ratio, 0.81; 95% confidence interval, 0.73-0.90), myocardial infarction (odds ratio, 0.82; 95% confidence interval, 0.75-0.89), and stroke (odds ratio, 0.77; 95% confidence interval, 0.66-0.88). Other end points, including resuscitation after cardiac arrest, myocardial revascularization, and hospitalization because of heart failure, were also reduced. Angiotensin-converting enzyme inhibitors reduce total mortality and major cardiovascular end points in patients who have CAD and no left ventricular systolic dysfunction or heart failure.
Sleep Duration and Health-Related Quality of Life in Predialysis CKD.
Sung, Su-Ah; Hyun, Young Youl; Lee, Kyu Beck; Park, Hayne Cho; Chung, Wookyung; Kim, Yeong Hoon; Kim, Yong-Soo; Park, Sue Kyung; Oh, Kook-Hwan; Ahn, Curie
2018-06-07
Sleep duration has been associated with cardiometabolic risk and mortality. The health-related quality of life represents a patient's comprehensive perception of health and is accepted as a health outcome. We examined the relationship between sleep duration and health-related quality of life in predialysis CKD. In this cross-sectional study, data from 1910 adults with CKD enrolled in the Korean Cohort Study for Outcome in Patients with CKD were analyzed. Health-related quality of life was assessed with the physical component summary and mental component summary of the Short Form-36 Health Survey. Low health-related quality of life was defined as a Short Form-36 Health Survey score >1 SD below the mean. Using a generalized additive model and multivariable logistic regression analysis, the relationship between self-reported sleep duration and health-related quality of life was examined. Seven-hour sleepers showed the highest health-related quality of life. We found an inverted U-shaped relationship between sleep duration and health-related quality of life as analyzed by a generalized additive model. In multivariable logistic analysis, short sleepers (≤5 h/d) had lower health-related quality of life (odds ratio, 3.23; 95% confidence interval, 1.86 to 5.60 for the physical component summary; odds ratio, 2.37; 95% confidence interval, 1.43 to 3.94 for the mental component summary), and long sleepers (≥9 h/d) had lower health-related quality of life (odds ratio, 2.80; 95% confidence interval, 1.55 to 5.03 for the physical component summary; odds ratio, 2.08; 95% confidence interval, 1.20 to 3.60 for the mental component summary) compared with 7-hour sleepers. Sleep duration had a significant U-shaped association with low health-related quality of life. These findings suggest that short or long sleep duration is independently associated with low health-related quality of life in adults with CKD. Copyright © 2018 by the American Society of Nephrology.
McLeod, Shelley L; Iansavichene, Alla; Cheskes, Sheldon
2017-05-17
Remote ischemic conditioning (RIC) is a noninvasive therapeutic strategy that uses brief cycles of blood pressure cuff inflation and deflation to protect the myocardium against ischemia-reperfusion injury. The objective of this systematic review was to determine the impact of RIC on myocardial salvage index, infarct size, and major adverse cardiovascular events when initiated before catheterization. Electronic searches of Medline, Embase, and Cochrane Central Register of Controlled Trials were conducted and reference lists were hand searched. Randomized controlled trials comparing percutaneous coronary intervention (PCI) with and without RIC for patients with ST-segment-elevation myocardial infarction were included. Two reviewers independently screened abstracts, assessed quality of the studies, and extracted data. Data were pooled using random-effects models and reported as mean differences and relative risk with 95% confidence intervals. Eleven articles (9 randomized controlled trials) were included with a total of 1220 patients (RIC+PCI=643, PCI=577). Studies with no events were excluded from meta-analysis. The myocardial salvage index was higher in the RIC+PCI group compared with the PCI group (mean difference: 0.08; 95% confidence interval, 0.02-0.14). Infarct size was reduced in the RIC+PCI group compared with the PCI group (mean difference: -2.46; 95% confidence interval, -4.66 to -0.26). Major adverse cardiovascular events were lower in the RIC+PCI group (9.5%) compared with the PCI group (17.0%; relative risk: 0.57; 95% confidence interval, 0.40-0.82). RIC appears to be a promising adjunctive treatment to PCI for the prevention of reperfusion injury in patients with ST-segment-elevation myocardial infarction; however, additional high-quality research is required before a change in practice can be considered. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.
Mumps vaccine performance among university students during a mumps outbreak.
Cortese, Margaret M; Jordan, Hannah T; Curns, Aaron T; Quinlan, Patricia A; Ens, Kim A; Denning, Patricia M; Dayan, Gustavo H
2008-04-15
The largest reported mumps outbreak at a US college in 19 years occurred in 2006 at a Kansas university with a 2-dose measles-mumps-rubella (MMR) vaccination policy. We assessed vaccine performance and mumps risk factors, including the possibility of waning vaccine protection. Case students were compared with a cohort of the university's approximately 19,000 undergraduates. The secondary attack rate for clinical mumps was determined among roommates exposed to case students. Time from receipt of the second dose of MMR vaccine was compared between case students and roommates without mumps. Coverage with > or =2 dose of MMR vaccine was > or =95% among 140 undergraduate case students and 444 cohort students. The secondary attack rate for clinical mumps among roommates who had received 2 doses of vaccine ranged from 2.2% to 7.7%, depending on the case definition. Compared with roommates without mumps, case students were more likely (odds ratio, 2.46; 95% confidence interval, 1.25-4.82) to have received their second dose of MMR vaccine > or =10 years earlier. The odds of being a case student increased with each 1-year increase in time from receipt of the second dose of MMR vaccine (odds ratio, 1.36; 95% confidence interval, 1.10-1.68) among case students and roommates aged 18-19 years but not among those aged > or =20 years. Students aged 18-19 years had a higher risk of mumps (risk ratio, 3.14; 95% confidence interval, 1.60-6.16), compared with students aged > or =22 years; women living in dormitories had increased risk of mumps (risk ratio, 1.95; 95% confidence interval, 1.01-3.76), compared with men not living in dormitories. High 2-dose MMR coverage protected many students from developing mumps but was not sufficient to prevent the mumps outbreak. Vaccine-induced protection may wane. Similar US settings where large numbers of young adults from wild-type naive cohorts live closely together may be at particular risk for mumps outbreaks.
Song, Yun; Xu, Benjamin; Xu, Richard; Tung, Renee; Frank, Eric; Tromble, Wayne; Fu, Tong; Zhang, Weiyi; Yu, Tao; Zhang, Chunyan; Fan, Fangfang; Zhang, Yan; Li, Jianping; Bao, Huihui; Cheng, Xiaoshu; Qin, Xianhui; Tang, Genfu; Chen, Yundai; Yang, Tianlun; Sun, Ningling; Li, Xiaoying; Zhao, Lianyou; Hou, Fan Fan; Ge, Junbo; Dong, Qiang; Wang, Binyan; Xu, Xiping; Huo, Yong
2016-07-01
Pulse wave velocity (PWV) has been shown to influence the effects of antihypertensive drugs in the prevention of cardiovascular diseases. Data are limited on whether PWV is an independent predictor of stroke above and beyond hypertension control. This longitudinal analysis examined the independent and joint effect of brachial-ankle PWV (baPWV) with hypertension control on the risk of first stroke. This report included 3310 hypertensive adults, a subset of the China Stroke Primary Prevention Trial (CSPPT) with baseline measurements for baPWV. During a median follow-up of 4.5 years, 111 participants developed first stroke. The risk of stroke was higher among participants with baPWV in the highest quartile than among those in the lower quartiles (6.3% versus 2.4%; hazard ratio, 1.66; 95% confidence interval, 1.06-2.60). Similarly, the participants with inadequate hypertension control had a higher risk of stroke than those with adequate control (5.1% versus 1.8%; hazard ratio, 2.32; 95% confidence interval, 1.49-3.61). When baPWV and hypertension control were examined jointly, participants in the highest baPWV quartile and with inadequate hypertension control had the highest risk of stroke compared with their counterparts (7.5% versus 1.3%; hazard ratio, 3.57; 95% confidence interval, 1.88-6.77). There was a significant and independent effect of high baPWV on stroke as shown among participants with adequate hypertension control (4.2% versus 1.3%; hazard ratio, 2.29, 95% confidence interval, 1.09-4.81). In summary, among hypertensive patients, baPWV and hypertension control were found to independently and jointly affect the risk of first stroke. Participants with high baPWV and inadequate hypertension control had the highest risk of stroke compared with other groups. © 2016 American Heart Association, Inc.
Muirhead, R; Drinkwater, K; O'Cathail, S M; Adams, R; Glynne-Jones, R; Harrison, M; Hawkins, M A; Sebag-Montefiore, D; Gilbert, D C
2017-03-01
UK guidance was recently developed for the treatment of anal cancer using intensity-modulated radiotherapy (IMRT). We audited the current use of radiotherapy in UK cancer centres for the treatment of anal cancer against such guidance. We describe the acute toxicity of IMRT in comparison with patient population in the audit treated with two-phase conformal radiotherapy and the previous published data from two-phase conformal radiotherapy, in the UK ACT2 trial. A Royal College of Radiologists' prospective national audit of patients treated with radiotherapy in UK cancer centres was carried out over a 6 month period between February and July 2015. Two hundred and forty-two cases were received from 40/56 cancer centres (71%). In total, 231 (95%) underwent full dose radiotherapy with prophylactic nodal irradiation. Of these, 180 (78%) received IMRT or equivalent, 52 (22%) two-phase conformal (ACT2) technique. The number of interruptions in radiotherapy treatment in the ACT2 trial was 15%. Interruptions were noted in 7% (95% confidence interval 0-14%) of courses receiving two-phase conformal and 4% (95% confidence interval 1-7%) of those receiving IMRT. The percentage of patients completing the planned radiotherapy dose, irrelevant of gaps, was 90% (95% confidence interval 82-98%) and 96% (95% confidence interval 93-99%), in two-phase conformal and IMRT respectively. The toxicity reported in the ACT2 trial, in patients receiving two-phase conformal in the audit and in patients receiving IMRT in the audit was: any toxic effect 71%, 54%, 48%, non-haematological 62%, 49%, 40% and haematological 26%, 13%, 18%, respectively. IMRT implementation for anal cancer is well underway in the UK with most patients receiving IMRT delivery, although its usage is not yet universal. This audit confirms that IMRT results in reduced acute toxicity and minimised treatment interruptions in comparison with previous two-phase conformal techniques. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Tran, Mark W; Weiland, Tracey J; Phillips, Georgina A
2015-01-01
Psychosocial factors such as marital status (odds ratio, 3.52; 95% confidence interval, 1.43-8.69; P = .006) and nonclinical factors such as outpatient nonattendances (odds ratio, 2.52; 95% confidence interval, 1.22-5.23; P = .013) and referrals made (odds ratio, 1.20; 95% confidence interval, 1.06-1.35; P = .003) predict hospital utilization for patients in a chronic disease management program. Along with optimizing patients' clinical condition by prescribed medical guidelines and supporting patient self-management, addressing psychosocial and nonclinical issues are important in attempting to avoid hospital utilization for people with chronic illnesses.
Health significance and statistical uncertainty. The value of P-value.
Consonni, Dario; Bertazzi, Pier Alberto
2017-10-27
The P-value is widely used as a summary statistics of scientific results. Unfortunately, there is a widespread tendency to dichotomize its value in "P<0.05" (defined as "statistically significant") and "P>0.05" ("statistically not significant"), with the former implying a "positive" result and the latter a "negative" one. To show the unsuitability of such an approach when evaluating the effects of environmental and occupational risk factors. We provide examples of distorted use of P-value and of the negative consequences for science and public health of such a black-and-white vision. The rigid interpretation of P-value as a dichotomy favors the confusion between health relevance and statistical significance, discourages thoughtful thinking, and distorts attention from what really matters, the health significance. A much better way to express and communicate scientific results involves reporting effect estimates (e.g., risks, risks ratios or risk differences) and their confidence intervals (CI), which summarize and convey both health significance and statistical uncertainty. Unfortunately, many researchers do not usually consider the whole interval of CI but only examine if it includes the null-value, therefore degrading this procedure to the same P-value dichotomy (statistical significance or not). In reporting statistical results of scientific research present effects estimates with their confidence intervals and do not qualify the P-value as "significant" or "not significant".
Abbott, Eduardo F; Serrano, Valentina P; Rethlefsen, Melissa L; Pandian, T K; Naik, Nimesh D; West, Colin P; Pankratz, V Shane; Cook, David A
2018-02-01
To characterize reporting of P values, confidence intervals (CIs), and statistical power in health professions education research (HPER) through manual and computerized analysis of published research reports. The authors searched PubMed, Embase, and CINAHL in May 2016, for comparative research studies. For manual analysis of abstracts and main texts, they randomly sampled 250 HPER reports published in 1985, 1995, 2005, and 2015, and 100 biomedical research reports published in 1985 and 2015. Automated computerized analysis of abstracts included all HPER reports published 1970-2015. In the 2015 HPER sample, P values were reported in 69/100 abstracts and 94 main texts. CIs were reported in 6 abstracts and 22 main texts. Most P values (≥77%) were ≤.05. Across all years, 60/164 two-group HPER studies had ≥80% power to detect a between-group difference of 0.5 standard deviations. From 1985 to 2015, the proportion of HPER abstracts reporting a CI did not change significantly (odds ratio [OR] 2.87; 95% CI 1.04, 7.88) whereas that of main texts reporting a CI increased (OR 1.96; 95% CI 1.39, 2.78). Comparison with biomedical studies revealed similar reporting of P values, but more frequent use of CIs in biomedicine. Automated analysis of 56,440 HPER abstracts found 14,867 (26.3%) reporting a P value, 3,024 (5.4%) reporting a CI, and increased reporting of P values and CIs from 1970 to 2015. P values are ubiquitous in HPER, CIs are rarely reported, and most studies are underpowered. Most reported P values would be considered statistically significant.
Dekkers, Olaf M; Cevallos, Myriam; Bührer, Jonas; Poncet, Antoine; Ackermann Rau, Sabine; Perneger, Thomas V; Egger, Matthias
2015-05-01
To compare noninferiority margins defined in study protocols and trial registry records with margins reported in subsequent publications. Comparison of protocols of noninferiority trials submitted 2001 to 2005 to ethics committees in Switzerland and The Netherlands with corresponding publications and registry records. We searched MEDLINE via PubMed, the Cochrane Controlled Trials Register (Cochrane Library issue 01/2012), and Google Scholar in September 2013 to identify published reports, and the International Clinical Trials Registry Platform of the World Health Organization in March 2013 to identify registry records. Two readers recorded the noninferiority margin and other data using a standardized data-abstraction form. The margin was identical in study protocol and publication in 43 (80%) of 54 pairs of study protocols and articles. In the remaining pairs, reporting was inconsistent (five pairs, 9%), or the noninferiority margin was either not reported in the publication (five pairs, 9%) or not defined in the study protocol (one pair). The confidence interval or the exact P-value required to judge whether the result was compatible with noninferior, inferior, or superior efficacy was reported in 43 (80%) publications. Complete and consistent reporting of both noninferiority margin and confidence interval (or exact P-value) was present in 39 (72%) protocol-publication pairs. Twenty-nine trials (54%) were registered in trial registries, but only one registry record included the noninferiority margin. The reporting of noninferiority margins was incomplete and inconsistent with study protocols in a substantial proportion of published trials, and margins were rarely reported in trial registries. Copyright © 2015 Elsevier Inc. All rights reserved.
Illness perception and adherence to healthy behaviour in Jordanian coronary heart disease patients.
Mosleh, Sultan M; Almalik, Mona Ma
2016-06-01
Patients diagnosed with coronary heart disease are strongly recommended to adopt healthier behaviours and adhere to prescribed medication. Previous research on patients with a wide range of health conditions has explored the role of patients' illness perceptions in explaining coping and health outcomes. However, among coronary heart disease patients, this has not been well examined. The purpose of this study was to explore coronary heart disease patients' illness perception beliefs and investigate whether these beliefs could predict adherence to healthy behaviours. A multi-centre cross-sectional study was conducted at four tertiary hospitals in Jordan. A convenience sample of 254 patients (73% response rate), who visited the cardiac clinic for routine review, participated in the study. Participants completed a self-reported questionnaire, which included the Brief Illness Perception Questionnaire, the Godin Leisure Time Activity questionnaire and the Morisky Medication Adherence Scale. Patients reported high levels of disease understanding (coherence) and they were convinced that they were able to control their condition by themselves and/or with appropriate treatment. Male patients perceived lower consequences (p<0.05) and had a better understanding of their illness than female patients (p<0.001). There were significant associations between increasing age and each of timeline (r=0.326, p<0.001), (r=0.146, p<0.024) and coherence (r=-0.166, p<0.010). Adjusted regression analysis showed that exercise adherence was predicted by both a strong perception in personal control (β 2.66, 95% confidence interval 1.28-4.04), timeline (β -1.85, 95% confidence interval 0. 8-2.88) and illness coherence (β 2.12, 95% confidence interval 0.35-3.90). Medication adherence was predicted by perception of personal control and treatment control. Adherence to a low-fat diet regimen was predicted by perception of illness coherence only (odds ratio 12, 95% confidence interval 1.04-1.33). Finally, the majority of patients thought that the cause of their heart problem was related to coronary heart disease risk factors such as obesity and high-fat meals. Patients' illness beliefs are candidates for a psycho-educational intervention that should be targeted at improved disease management practices and better adherence to recommended healthy behaviours. © The European Society of Cardiology 2014.
Solomon, Scott D; Claggett, Brian; Desai, Akshay S; Packer, Milton; Zile, Michael; Swedberg, Karl; Rouleau, Jean L; Shi, Victor C; Starling, Randall C; Kozan, Ömer; Dukat, Andrej; Lefkowitz, Martin P; McMurray, John J V
2016-03-01
The angiotensin receptor neprilysin inhibitor sacubitril/valsartan (LCZ696) reduced cardiovascular morbidity and mortality compared with enalapril in patients with heart failure (HF) and reduced ejection fraction (EF) in the Prospective Comparison of ARNI with ACEI to Determine Impact on Global Mortality and Morbidity in Heart Failure (PARADIGM-HF) trial. We evaluated the influence of EF on clinical outcomes and on the effectiveness of sacubitril/valsartan compared with enalapril. Eight thousand three hundred ninety-nine patients with New York Heart Association class II to IV HF with reduced EF [left ventricular EF (LVEF) ≤40%] were randomized to sacubitril/valsartan 97/103 mg twice daily versus enalapril 10 mg twice daily and followed for a median of 27 months. The primary study end point was cardiovascular death or HF hospitalization. LVEF was assessed at the sites and recorded on case report forms. We related LVEF to study outcomes and assessed the effectiveness of sacubitril/valsartan across the LVEF spectrum. The mean LVEF in PARADIGM-HF, reported by sites, was 29.5 (interquartile range, 25-34). The risk of all outcomes increased with decreasing LVEF. Each 5-point reduction in LVEF was associated with a 9% increased risk of cardiovascular death or HF hospitalization (hazard ratio, 1.09; 95% confidence interval, 1.05-1.13; P<0.001), a 9% increased risk for CV death (hazard ratio, 1.09; 95% confidence interval, 1.04-1.14), a 9% increased risk in HF hospitalization (hazard ratio, 1.09; 95% confidence interval, 1.04-1.14) and a 7% increased risk in all-cause mortality (hazard ratio, 1.07; 95% confidence interval, 1.03-1.12) in adjusted analyses. Sacubitril/valsartan was effective across the LVEF spectrum, with no evidence of heterogeneity, when modeled either in tertiles (P interaction=0.87) or continuously (P interaction=0.95). In patients with HF and reduced EF enrolled in PARADIGM-HF, LVEF was a significant and independent predictor of all outcomes. Sacubitril/valsartan was effective at reducing cardiovascular death and HF hospitalization throughout the LVEF spectrum. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01035255. © 2016 American Heart Association, Inc.
Buffel du Vaure, Céline; Boutron, Isabelle; Perrodeau, Elodie; Ravaud, Philippe
2014-04-28
Systematic reporting of funding sources is recommended in the CONSORT Statement for abstracts. However, no specific recommendation is related to the reporting of conflicts of interest (CoI). The objective was to compare physicians' confidence in the conclusions of abstracts of randomized controlled trials of pharmaceutical treatment indexed in PubMed. We planned a three-arm parallel-group randomized trial. French general practitioners (GPs) were invited to participate and were blinded to the study's aim. We used a representative sample of 75 abstracts of pharmaceutical industry-funded randomized controlled trials published in 2010 and indexed in PubMed. Each abstract was standardized and reported in three formats: 1) no mention of the funding source or CoI; 2) reporting the funding source only; and 3) reporting the funding source and CoI. GPs were randomized according to a computerized randomization on a secure Internet system at a 1:1:1 ratio to assess one abstract among the three formats. The primary outcome was GPs' confidence in the abstract conclusions (0, not at all, to 10, completely confident). The study was planned to detect a large difference with an effect size of 0.5. Between October 2012 and June 2013, among 605 GPs contacted, 354 were randomized, 118 for each type of abstract. The mean difference (95% confidence interval) in GPs' confidence in abstract findings was 0.2 (-0.6; 1.0) (P = 0.84) for abstracts reporting the funding source only versus no funding source or CoI; -0.4 (-1.3; 0.4) (P = 0.39) for abstracts reporting the funding source and CoI versus no funding source and CoI; and -0.6 (-1.5; 0.2) (P = 0.15) for abstracts reporting the funding source and CoI versus the funding source only. We found no evidence of a large impact of trial report abstracts mentioning funding sources or CoI on GPs' confidence in the conclusions of the abstracts. ClinicalTrials.gov identifier: NCT01679873.
Confidence Interval Coverage for Cohen's Effect Size Statistic
ERIC Educational Resources Information Center
Algina, James; Keselman, H. J.; Penfield, Randall D.
2006-01-01
Kelley compared three methods for setting a confidence interval (CI) around Cohen's standardized mean difference statistic: the noncentral-"t"-based, percentile (PERC) bootstrap, and biased-corrected and accelerated (BCA) bootstrap methods under three conditions of nonnormality, eight cases of sample size, and six cases of population…
Persistent opioid use following Cesarean delivery: patterns and predictors among opioid naïve women
Bateman, Brian T.; Franklin, Jessica M.; Bykov, Katsiaryna; Avorn, Jerry; Shrank, William H.; Brennan, Troyen A.; Landon, Joan E.; Rathmell, James P.; Huybrechts, Krista F.; Fischer, Michael A.; Choudhry, Niteesh K.
2016-01-01
Background The incidence of opioid-related death in women has increased five-fold over the past decade. For many women, their initial opioid exposure will occur in the setting of routine medical care. Approximately 1 in 3 deliveries in the U.S. is by Cesarean and opioids are commonly prescribed for post-surgical pain management. Objective The objective of this study was to determine the risk that opioid naïve women prescribed opioids after Cesarean delivery will subsequently become consistent prescription opioid users in the year following delivery, and to identify predictors for this behavior. Study Design We identified women in a database of commercial insurance beneficiaries who underwent Cesarean delivery and who were opioid-naïve in the year prior to delivery. To identify persistent users of opioids, we used trajectory models, which group together patients with similar patterns of medication filling during follow-up, based on patterns of opioid dispensing in the year following Cesarean delivery. We then constructed a multivariable logistic regression model to identify independent risk factors for membership in the persistent user group. Results 285 of 80,127 (0.36%, 95% confidence interval 0.32 to 0.40), opioid-naïve women became persistent opioid users (identified using trajectory models based on monthly patterns of opioid dispensing) following Cesarean delivery. Demographics and baseline comorbidity predicted such use with moderate discrimination (c statistic = 0.73). Significant predictors included a history of cocaine abuse (risk 7.41%; adjusted odds ratio 6.11, 95% confidence interval 1.03 to 36.31) and other illicit substance abuse (2.36%; adjusted odds ratio 2.78, 95% confidence interval 1.12 to 6.91), tobacco use (1.45%; adjusted odds ratio 3.04, 95% confidence interval 2.03 to 4.55), back pain (0.69%; adjusted odds ratio 1.74, 95% confidence interval 1.33 to 2.29), migraines (0.91%; adjusted odds ratio 2.14, 95% confidence interval 1.58 to 2.90), antidepressant use (1.34%; adjusted odds ratio 3.19, 95% confidence interval 2.41 to 4.23) and benzodiazepine use (1.99%; adjusted odds ratio 3.72, 95% confidence interval 2.64 to 5.26) in the year prior to Cesarean delivery. Conclusions A very small proportion of opioid-naïve women (approximately 1 in 300) become persistent prescription opioid users following Cesarean delivery. Pre-existing psychiatric comorbidity, certain pain conditions, and substance use/abuse conditions identifiable at the time of initial opioid prescribing were predictors of persistent use. PMID:26996986
Emergency department patient satisfaction survey in Imam Reza Hospital, Tabriz, Iran
2011-01-01
Introduction Patient satisfaction is an important indicator of the quality of care and service delivery in the emergency department (ED). The objective of this study was to evaluate patient satisfaction with the Emergency Department of Imam Reza Hospital in Tabriz, Iran. Methods This study was carried out for 1 week during all shifts. Trained researchers used the standard Press Ganey questionnaire. Patients were asked to complete the questionnaire prior to discharge. The study questionnaire included 30 questions based on a Likert scale. Descriptive and analytical statistics were used throughout data analysis in a number of ways using SPSS version 13. Results Five hundred patients who attended our ED were included in this study. The highest satisfaction rates were observed in the terms of physicians' communication with patients (82.5%), security guards' courtesy (78.3%) and nurses' communication with patients (78%). The average waiting time for the first visit to a physician was 24 min 15 s. The overall satisfaction rate was dependent on the mean waiting time. The mean waiting time for a low rate of satisfaction was 47 min 11 s with a confidence interval of (19.31, 74.51), and for very good level of satisfaction it was 14 min 57 s with a (10.58, 18.57) confidence interval. Approximately 63% of the patients rated their general satisfaction with the emergency setting as good or very good. On the whole, the patient satisfaction rate at the lowest level was 7.7 with a confidence interval of (5.1, 10.4), and at the low level it was 5.8% with a confidence interval of (3.7, 7.9). The rate of satisfaction for the mediocre level was 23.3 with a confidence interval of (19.1, 27.5); for the high level of satisfaction it was 28.3 with a confidence interval of (22.9, 32.8), and for the very high level of satisfaction, this rate was 32.9% with a confidence interval of (28.4, 37.4). Conclusion The study findings indicated the need for evidence-based interventions in emergency care services in areas such as medical care, nursing care, courtesy of staff, physical comfort and waiting time. Efforts should focus on shortening waiting intervals and improving patients' perceptions about waiting in the ED, and also improving the overall cleanliness of the emergency room. PMID:21407998
ERIC Educational Resources Information Center
Young, Jamaal Rashad; Young, Jemimah Lea
2016-01-01
In this article, the authors provide a single group summary using the Mathematics Anxiety Rating Scale (MARS) to characterize and delineate the measurement of mathematics anxiety (MA) reported among Black students. Two research questions are explored: (a) What are the characteristics of studies administering the MARS and its derivatives to…
Khan, Ainee; Dickens, Andrew P; Adab, Peymane; Jordan, Rachel E
2017-07-20
Self-management support for chronic obstructive pulmonary disease (COPD) patients is recommended by UK national guidelines, but extent of implementation is unknown. We aimed to describe self-management behaviour and support among COPD patients and explore behaviour associated with having a self-management plan. We undertook cross-sectional analysis of self-reported data from diagnosed COPD patients in the Birmingham COPD Cohort study. Questionnaire items relevant to self-management behaviour, knowledge of COPD, receipt of self-management plans and advice from healthcare professionals were examined. Multiple regression models were used to identify behaviour associated with having a self-management plan. One-thousand seventy-eight participants (676 males, 62.7%, mean age 69.8 (standard deviation 9.0) years) were included. The majority reported taking medications as instructed (940, 94.0%) and receiving annual influenza vaccinations (962, 89.2%). Only 400 (40.4%) participants had self-management plans, 538 (49.9%) reported never having received advice on diet/exercise and 110 (42.7%) current smokers had been offered practical help to stop smoking in the previous year. General knowledge about COPD was moderate (mean total Bristol COPD Knowledge Questionnaire score: 31.5 (standard deviation 10.7); max score 65), corresponding to 48.5% of questions answered correctly. Having a self-management plan was positively associated with self-reported adherence to medication (odds ratio 3.10, 95% confidence interval 1.43 to 6.72), attendance at a training course (odds ratio 2.72, 95% confidence interval 1.81 to 4.12), attendance at a support group (odds ratio 6.28, 95% confidence interval 2.96 to 13.35) and better disease knowledge (mean difference 4.87, 95% confidence interval 3.16 to 6.58). Primary care healthcare professionals should ensure more widespread implementation of individualised self-management plans for all patients and improve the lifestyle advice provided. CALL FOR WIDER IMPLEMENTATION OF SELF-MANAGEMENT PLANS: Health professionals should ensure all patients with chronic lung disease receive individualized self-management plans and lifestyle advice. UK national guidelines state that patients with chronic obstructive pulmonary disease (COPD) should receive personalized self-management plans and comprehensive support to help them manage their disease. Ainee Khan and colleagues at the University of Birmingham analyzed patient questionnaire data gathered during the Birmingham COPD Cohort study to explore self-management behavior, receipt of self-management plans and advice, and patient knowledge of COPD. Of 1,078 participants, only 400 had self-management plans, and less than half reported receiving lifestyle advice or support. Those with plans were more likely to adhere to medication, had greater knowledge about COPD and were more likely to attend support groups and training courses. The authors recommend carefully-planned, wider implementation of COPD self-management plans and associated support.
Khan, Muhammad; Lin, Jie; Liao, Guixiang; Li, Rong; Wang, Baiyao; Xie, Guozhu; Zheng, Jieling; Yuan, Yawei
2017-07-01
Whole brain radiotherapy has been a standard treatment of brain metastases. Stereotactic radiosurgery provides more focal and aggressive radiation and normal tissue sparing but worse local and distant control. This meta-analysis was performed to assess and compare the effectiveness of whole brain radiotherapy alone, stereotactic radiosurgery alone, and their combination in the treatment of brain metastases based on randomized controlled trial studies. Electronic databases (PubMed, MEDLINE, Embase, and Cochrane Library) were searched to identify randomized controlled trial studies that compared treatment outcome of whole brain radiotherapy and stereotactic radiosurgery. This meta-analysis was performed using the Review Manager (RevMan) software (version 5.2) that is provided by the Cochrane Collaboration. The data used were hazard ratios with 95% confidence intervals calculated for time-to-event data extracted from survival curves and local tumor control rate curves. Odds ratio with 95% confidence intervals were calculated for dichotomous data, while mean differences with 95% confidence intervals were calculated for continuous data. Fixed-effects or random-effects models were adopted according to heterogeneity. Five studies (n = 763) were included in this meta-analysis meeting the inclusion criteria. All the included studies were randomized controlled trials. The sample size ranged from 27 to 331. In total 202 (26%) patients with whole brain radiotherapy alone, 196 (26%) patients receiving stereotactic radiosurgery alone, and 365 (48%) patients were in whole brain radiotherapy plus stereotactic radiosurgery group. No significant survival benefit was observed for any treatment approach; hazard ratio was 1.19 (95% confidence interval: 0.96-1.43, p = 0.12) based on three randomized controlled trials for whole brain radiotherapy only compared to whole brain radiotherapy plus stereotactic radiosurgery and hazard ratio was 1.03 (95% confidence interval: 0.82-1.29, p = 0.81) for stereotactic radiosurgery only compared to combined approach. Local control was best achieved when whole brain radiotherapy was combined with stereotactic radiosurgery. Hazard ratio 2.05 (95% confidence interval: 1.36-3.09, p = 0.0006) and hazard ratio 1.84 (95% confidence interval: 1.26-2.70, p = 0.002) were obtained from comparing whole brain radiotherapy only and stereotactic radiosurgery only to whole brain radiotherapy + stereotactic radiosurgery, respectively. No difference in adverse events for treatment difference; odds ratio 1.16 (95% confidence interval: 0.77-1.76, p = 0.48) and odds ratio 0.92 (95% confidence interval: 0.59-1.42, p = 71) for whole brain radiotherapy + stereotactic radiosurgery versus whole brain radiotherapy only and whole brain radiotherapy + stereotactic radiosurgery versus stereotactic radiosurgery only, respectively. Adding stereotactic radiosurgery to whole brain radiotherapy provides better local control as compared to whole brain radiotherapy only and stereotactic radiosurgery only with no difference in radiation related toxicities.
Rundek, Tatjana; Elkind, Mitchell S V; Di Tullio, Marco R; Carrera, Emmanuel; Jin, Zhezhen; Sacco, Ralph L; Homma, Shunichi
2008-09-30
A causal relationship between patent foramen ovale (PFO) and migraine has been hypothesized, and improvement of migraine frequency and severity after percutaneous PFO closure has been reported. Population-based data on the relationship between PFO and migraine are sparse, however. The objective of this study was to examine the association between PFO and migraine among stroke-free individuals in an urban, population-based, multiethnic cohort. As a part of the ongoing Northern Manhattan Study (NOMAS), 1101 stroke-free subjects were assessed for self-reported history of migraine. The presence of PFO was assessed by transthoracic echocardiography. The mean age of the group was 69+/-10 years; 58% were women. Forty-eight percent were Caribbean Hispanic, 24% were white, 26% were black, and 2% were another race/ethnicity. The prevalence of self-reported migraine was 16% (13% migraine with aura). The prevalence of PFO was 15%. Migraine was significantly more frequent among younger subjects, women, and Hispanics. The prevalence of PFO was not significantly different between subjects who had migraine (26/178, or 14.6%) and those who did not (138/923, or 15.0%; P=0.9). In an adjusted multivariate logistic regression model, the presence of PFO was not associated with increased prevalence of migraine (odds ratio 1.01, 95% confidence interval 0.63 to 1.61). Increasing age was associated with lower prevalence of migraine in both subjects with a PFO (odds ratio 0.94, 95% confidence interval 0.90 to 0.99 per year) and those without PFO (odds ratio 0.97, 95% confidence interval 0.95 to 0.99 per year). The observed lack of association between PFO and migraine (with or without aura) was not modified by diabetes mellitus, hypertension, cigarette smoking, or dyslipidemia. In this multiethnic, elderly, population-based cohort, PFO detected with transthoracic echocardiography and agitated saline was not associated with self-reported migraine. The causal relationship between PFO and migraine remains uncertain, and the role of PFO closure among unselected patients with migraine remains questionable.
Matziou, Vasiliki; Vlachioti, Efrosini; Megapanou, Eustathia; Ntoumou, Agapi; Dionisakopoulou, Christina; Dimitriou, Vasia; Tsoumakas, Konstantinos; Matziou, Theodora; Perdikaris, Pantelis
2016-09-01
The aim of the study was to assess pain levels and perceptions concerning pain by both children and their parents during hospitalization, as well as the impact of that pain upon parents' quality of life. The sample of the study consisted of 92 pediatric cancer patients, 159 pediatric patients with musculoskeletal problems and one of their parents. The study was performed between November 2010 and May 2011. The Pediatric Pain Questionnaire (Parent Version) and the PedsQL-Family Impact Module were used for pain assessment and the quality of life by the parents. Young patients completed the pediatric version of the Pediatric Pain Questionnaire for the evaluation of pediatric pain. Pain was measured by using the Wong-Baker facial pain scale, included in both parent and child version of the Pediatric Pain Questionnaire. This rating scale is recommended for children 3 years and older. Young patients reported higher acute pain scores than their parents (z = -2.5, P = 0.011; 99% confidence interval: 0.008-0.013). Young patients with orthopedic disorders had higher acute and chronic pain scores in comparison to their parents' reports (z = -3.4, P = 0.001; 99% confidence interval: 0.000-0.001 and z = -2.3, P = 0.021; 99% confidence interval: 0.017-0.025, respectively). Girls reported higher pain scores than boys (z = -2.0, P = 0.047; 99% CI: 0.041-0.052). Parental reports tended to underestimated children's pain, especially acute pain. The sex of children, the age and the marital status affect the perceptions of both children and their parents about pain. The parental quality of life is affected especially when the pain is caused by life-threatening diseases such as cancer. However, it improves as the treatment of their children is completed with no complications. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Coefficient Omega Bootstrap Confidence Intervals: Nonnormal Distributions
ERIC Educational Resources Information Center
Padilla, Miguel A.; Divers, Jasmin
2013-01-01
The performance of the normal theory bootstrap (NTB), the percentile bootstrap (PB), and the bias-corrected and accelerated (BCa) bootstrap confidence intervals (CIs) for coefficient omega was assessed through a Monte Carlo simulation under conditions not previously investigated. Of particular interests were nonnormal Likert-type and binary items.…
WASP (Write a Scientific Paper) using Excel - 6: Standard error and confidence interval.
Grech, Victor
2018-03-01
The calculation of descriptive statistics includes the calculation of standard error and confidence interval, an inevitable component of data analysis in inferential statistics. This paper provides pointers as to how to do this in Microsoft Excel™. Copyright © 2018 Elsevier B.V. All rights reserved.
Robust Confidence Interval for a Ratio of Standard Deviations
ERIC Educational Resources Information Center
Bonett, Douglas G.
2006-01-01
Comparing variability of test scores across alternate forms, test conditions, or subpopulations is a fundamental problem in psychometrics. A confidence interval for a ratio of standard deviations is proposed that performs as well as the classic method with normal distributions and performs dramatically better with nonnormal distributions. A simple…
The microcomputer scientific software series 2: general linear model--regression.
Harold M. Rauscher
1983-01-01
The general linear model regression (GLMR) program provides the microcomputer user with a sophisticated regression analysis capability. The output provides a regression ANOVA table, estimators of the regression model coefficients, their confidence intervals, confidence intervals around the predicted Y-values, residuals for plotting, a check for multicollinearity, a...
Toward Using Confidence Intervals to Compare Correlations
ERIC Educational Resources Information Center
Zou, Guang Yong
2007-01-01
Confidence intervals are widely accepted as a preferred way to present study results. They encompass significance tests and provide an estimate of the magnitude of the effect. However, comparisons of correlations still rely heavily on significance testing. The persistence of this practice is caused primarily by the lack of simple yet accurate…
Jelovsek, J Eric; Barber, Matthew D
2006-05-01
Women who seek treatment for pelvic organ prolapse strive for an improvement in quality of life. Body image has been shown to be an important component of differences in quality of life. To date, there are no data on body image in patients with advanced pelvic organ prolapse. Our objective was to compare body image and quality of life in women with advanced pelvic organ prolapse with normal controls. We used a case-control study design. Cases were defined as subjects who presented to a tertiary urogynecology clinic with advanced pelvic organ prolapse (stage 3 or 4). Controls were defined as subjects who presented to a tertiary care gynecology or women's health clinic for an annual visit with normal pelvic floor support (stage 0 or 1) and without urinary incontinence. All patients completed a valid and reliable body image scale and a generalized (Short Form Health Survey) and condition-specific (Pelvic Floor Distress Inventory-20) quality-of-life scale. Linear and logistic regression analyses were performed to adjust for possible confounding variables. Forty-seven case and 51 control subjects were enrolled. After controlling for age, race, parity, previous hysterectomy, and medical comorbidities, subjects with advanced pelvic organ prolapse were more likely to feel self-conscious (adjusted odds ratio 4.7; 95% confidence interval 1.4 to 18, P = .02), less likely to feel physically attractive (adjusted odds ratio 11; 95% confidence interval 2.9 to 51, P < .001), less likely to feel feminine (adjusted odds ratio 4.0; 95% confidence interval 1.2 to 15, P = .03), and less likely to feel sexually attractive (adjusted odds ratio 4.6; 95% confidence interval 1.4 to 17, P = .02) than normal controls. The groups were similar in their feeling of dissatisfaction with appearance when dressed, difficulty looking at themselves naked, avoiding people because of appearance, and overall dissatisfaction with their body. Subjects with advanced pelvic organ prolapse suffered significantly lower quality of life on the physical scale of the SF-12 (mean 42; 95% confidence interval 39 to 45 versus mean 50; 95% confidence interval 47 to 53, P < .009). However, no differences between groups were noted on the mental scale of the SF-12 (mean 51; 95% confidence interval 50 to 54 versus mean 50; 95% confidence interval 47 to 52, P = .56). Additionally, subjects with advanced pelvic organ prolapse scored significantly worse on the prolapse, urinary, and colorectal scales and overall summary score of Pelvic Floor Distress Inventory-20 than normal controls (mean summary score 104; 95% confidence interval 90 to 118 versus mean 29; 95% confidence interval 16 to 43, P < .0001), indicating a decrease in condition-specific quality of life. Worsening body image correlated with lower quality of life on both the physical and mental scales of the SF-12 as well as the prolapse, urinary, and colorectal scales and overall summary score of Pelvic Floor Distress Inventory-20 in subjects with advanced pelvic organ prolapse. Women seeking treatment for advanced pelvic organ prolapse have decreased body image and overall quality of life. Body image may be a key determinant for quality of life in patients with advanced prolapse and may be an important outcome measure for treatment evaluation in clinical trials.
Odgaard, Eric C; Fowler, Robert L
2010-06-01
In 2005, the Journal of Consulting and Clinical Psychology (JCCP) became the first American Psychological Association (APA) journal to require statistical measures of clinical significance, plus effect sizes (ESs) and associated confidence intervals (CIs), for primary outcomes (La Greca, 2005). As this represents the single largest editorial effort to improve statistical reporting practices in any APA journal in at least a decade, in this article we investigate the efficacy of that change. All intervention studies published in JCCP in 2003, 2004, 2007, and 2008 were reviewed. Each article was coded for method of clinical significance, type of ES, and type of associated CI, broken down by statistical test (F, t, chi-square, r/R(2), and multivariate modeling). By 2008, clinical significance compliance was 75% (up from 31%), with 94% of studies reporting some measure of ES (reporting improved for individual statistical tests ranging from eta(2) = .05 to .17, with reasonable CIs). Reporting of CIs for ESs also improved, although only to 40%. Also, the vast majority of reported CIs used approximations, which become progressively less accurate for smaller sample sizes and larger ESs (cf. Algina & Kessleman, 2003). Changes are near asymptote for ESs and clinical significance, but CIs lag behind. As CIs for ESs are required for primary outcomes, we show how to compute CIs for the vast majority of ESs reported in JCCP, with an example of how to use CIs for ESs as a method to assess clinical significance.
Perceived impact of the Medicare policy to adjust payment for health care-associated infections
Lee, Grace M.; Hartmann, Christine W.; Graham, Denise; Kassler, William; Linn, Maya Dutta; Krein, Sarah; Saint, Sanjay; Goldmann, Donald A.; Fridkin, Scott; Horan, Teresa; Jernigan, John; Jha, Ashish
2014-01-01
Background In 2008, the Centers for Medicare and Medicaid Services (CMS) ceased additional payment for hospitalizations resulting in complications deemed preventable, including several health care-associated infections. We sought to understand the impact of the CMS payment policy on infection prevention efforts. Methods A national survey of infection preventionists from a random sample of US hospitals was conducted in December 2010. Results Eighty-one percent reported increased attention to HAIs targeted by the CMS policy, whereas one-third reported spending less time on nontargeted HAIs. Only 15% reported increased funding for infection control as a result of the CMS policy, whereas most reported stable (77%) funding. Respondents reported faster removal of urinary (71%) and central venous (50%) catheters as a result of the CMS policy, whereas routine urine and blood cultures on admission occurred infrequently (27% and 13%, respectively). Resource shifting (ie, less time spent on nontargeted HAIs) occurred more commonly in large hospitals (odds ratio, 2.3; 95% confidence interval: 1.0–5.1; P = .038) but less often in hospitals where front-line staff were receptive to changes in clinical processes (odds ratio, 0.5; 95% confidence interval: 0.3–0.8; P = .005). Conclusion Infection preventionists reported greater hospital attention to preventing targeted HAIs as a result of the CMS nonpayment policy. Whether the increased focus and greater engagement in HAI prevention practices has led to better patient outcomes is unclear. PMID:22541855
Identifying family members who may struggle in the role of surrogate decision maker.
Majesko, Alyssa; Hong, Seo Yeon; Weissfeld, Lisa; White, Douglas B
2012-08-01
Although acting as a surrogate decision maker can be highly distressing for some family members of intensive care unit patients, little is known about whether there are modifiable risk factors for the occurrence of such difficulties. To identify: 1) factors associated with lower levels of confidence among family members to function as surrogates and 2) whether the quality of clinician-family communication is associated with the timing of decisions to forego life support. We conducted a prospective study of 230 surrogate decision makers for incapacitated, mechanically ventilated patients at high risk of death in four intensive care units at University of California San Francisco Medical Center from 2006 to 2007. Surrogates completed a questionnaire addressing their perceived ability to act as a surrogate and the quality of their communication with physicians. We used clustered multivariate logistic regression to identify predictors of low levels of perceived ability to act as a surrogate and a Cox proportional hazard model to determine whether quality of communication was associated with the timing of decisions to withdraw life support. There was substantial variability in family members' confidence to act as surrogate decision makers, with 27% rating their perceived ability as 7 or lower on a 10-point scale. Independent predictors of lower role confidence were the lack of prior experience as a surrogate (odds ratio 2.2, 95% confidence interval [1.04-4.46], p=.04), no prior discussions with the patient about treatment preferences (odds ratio 3.7, 95% confidence interval [1.79-7.76], p<.001), and poor quality of communication with the ICU physician (odds ratio 1.2, 95% confidence interval [1.09-1.35] p<.001). Higher quality physician-family communication was associated with a significantly shorter duration of life-sustaining treatment among patients who died (β=0.11, p=.001). Family members without prior experience as a surrogate and those who had not engaged in advanced discussions with the patient about treatment preferences were at higher risk to report less confidence in carrying out the surrogate role. Better-quality clinician-family communication was associated with both more confidence among family members to act as surrogates and a shorter duration of use of life support among patients who died.
Inverse modeling with RZWQM2 to predict water quality
Nolan, Bernard T.; Malone, Robert W.; Ma, Liwang; Green, Christopher T.; Fienen, Michael N.; Jaynes, Dan B.
2011-01-01
This chapter presents guidelines for autocalibration of the Root Zone Water Quality Model (RZWQM2) by inverse modeling using PEST parameter estimation software (Doherty, 2010). Two sites with diverse climate and management were considered for simulation of N losses by leaching and in drain flow: an almond [Prunus dulcis (Mill.) D.A. Webb] orchard in the San Joaquin Valley, California and the Walnut Creek watershed in central Iowa, which is predominantly in corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] rotation. Inverse modeling provides an objective statistical basis for calibration that involves simultaneous adjustment of model parameters and yields parameter confidence intervals and sensitivities. We describe operation of PEST in both parameter estimation and predictive analysis modes. The goal of parameter estimation is to identify a unique set of parameters that minimize a weighted least squares objective function, and the goal of predictive analysis is to construct a nonlinear confidence interval for a prediction of interest by finding a set of parameters that maximizes or minimizes the prediction while maintaining the model in a calibrated state. We also describe PEST utilities (PAR2PAR, TSPROC) for maintaining ordered relations among model parameters (e.g., soil root growth factor) and for post-processing of RZWQM2 outputs representing different cropping practices at the Iowa site. Inverse modeling provided reasonable fits to observed water and N fluxes and directly benefitted the modeling through: (i) simultaneous adjustment of multiple parameters versus one-at-a-time adjustment in manual approaches; (ii) clear indication by convergence criteria of when calibration is complete; (iii) straightforward detection of nonunique and insensitive parameters, which can affect the stability of PEST and RZWQM2; and (iv) generation of confidence intervals for uncertainty analysis of parameters and model predictions. Composite scaled sensitivities, which reflect the total information provided by the observations for a parameter, indicated that most of the RZWQM2 parameters at the California study site (CA) and Iowa study site (IA) could be reliably estimated by regression. Correlations obtained in the CA case indicated that all model parameters could be uniquely estimated by inverse modeling. Although water content at field capacity was highly correlated with bulk density (−0.94), the correlation is less than the threshold for nonuniqueness (0.95, absolute value basis). Additionally, we used truncated singular value decomposition (SVD) at CA to mitigate potential problems with highly correlated and insensitive parameters. Singular value decomposition estimates linear combinations (eigenvectors) of the original process-model parameters. Parameter confidence intervals (CIs) at CA indicated that parameters were reliably estimated with the possible exception of an organic pool transfer coefficient (R45), which had a comparatively wide CI. However, the 95% confidence interval for R45 (0.03–0.35) is mostly within the range of values reported for this parameter. Predictive analysis at CA generated confidence intervals that were compared with independently measured annual water flux (groundwater recharge) and median nitrate concentration in a collocated monitoring well as part of model evaluation. Both the observed recharge (42.3 cm yr−1) and nitrate concentration (24.3 mg L−1) were within their respective 90% confidence intervals, indicating that overall model error was within acceptable limits.
Communication in critical care environments: mobile telephones improve patient care.
Soto, Roy G; Chu, Larry F; Goldman, Julian M; Rampil, Ira J; Ruskin, Keith J
2006-02-01
Most hospital policies prohibiting the use of wireless devices cite reports of disruption of medical equipment by cellular telephones. There have been no studies to determine whether mobile telephones may have a beneficial impact on safety. At the 2003 meeting of the American Society of Anesthesiologists 7878 surveys were distributed to attendees. The five-question survey polled anesthesiologists regarding modes of communication used in the operating room/intensive care unit and experience with communications delays and medical errors. Survey reliability was verified using test-retest analysis and proportion agreement in a convenience sample of 17 anesthesiologists. Four-thousand-eighteen responses were received. The test-retest reliability of the survey instrument was excellent (Kappa = 0.75; 95% confidence interval, 0.56-0.94). Sixty-five percent of surveyed anesthesiologists reported using pagers as their primary mode of communications, whereas only 17% used cellular telephones. Forty-five percent of respondents who use pagers reported delays in communications compared with 31% of cellular telephone users. Cellular telephone use by anesthesiologists is associated with a reduction in the risk of medical error or injury resulting from communication delay (relative risk = 0.78; 95% confidence interval, 0.6234-0.9649). The small risks of electromagnetic interference between mobile telephones and medical devices should be weighed against the potential benefits of improved communication.
Global Prevalence of Elder Abuse: A Meta-analysis and Meta-regression.
Ho, C Sh; Wong, S Y; Chiu, M M; Ho, R Cm
2017-06-01
Elder abuse is increasingly recognised as a global public health and social problem. There has been limited inter-study comparison of the prevalence and risk factors for elder abuse. This study aimed to estimate the pooled and subtype prevalence of elder abuse worldwide and identify significant associated risk factors. We conducted a meta-analysis and meta-regression of 34 population-based and 17 non-population-based studies. The pooled prevalences of elder abuse were 10.0% (95% confidence interval, 5.2%-18.6%) and 34.3% (95% confidence interval, 22.9%-47.8%) in population-based studies and third party- or caregiver-reported studies, respectively. Being in a marital relationship was found to be a significant moderator using random-effects model. This meta-analysis revealed that third parties or caregivers were more likely to report abuse than older abused adults. Subgroup analyses showed that females and those resident in non-western countries were more likely to be abused. Emotional abuse was the most prevalent elder abuse subtype and financial abuse was less commonly reported by third parties or caregivers. Heterogeneity in the prevalence was due to the high proportion of married older adults in the sample. Subgroup analysis showed that cultural factors, subtypes of abuse, and gender also contributed to heterogeneity in the pooled prevalence of elder abuse.
A simple method for assessing occupational exposure via the one-way random effects model.
Krishnamoorthy, K; Mathew, Thomas; Peng, Jie
2016-11-01
A one-way random effects model is postulated for the log-transformed shift-long personal exposure measurements, where the random effect in the model represents an effect due to the worker. Simple closed-form confidence intervals are proposed for the relevant parameters of interest using the method of variance estimates recovery (MOVER). The performance of the confidence bounds is evaluated and compared with those based on the generalized confidence interval approach. Comparison studies indicate that the proposed MOVER confidence bounds are better than the generalized confidence bounds for the overall mean exposure and an upper percentile of the exposure distribution. The proposed methods are illustrated using a few examples involving industrial hygiene data.
Walter, William R; Goldberg-Stein, Shlomit; Levsky, Jeffrey M; Cohen, Hillel W; Scheinfeld, Meir H
2015-08-01
The aim of this study was to compare the accuracy of coronary atherosclerosis reporting before and after the implementation of a structured reporting chest CT template. A noncardiac, noncontrast chest CT structured reporting template was developed and mandated for department-wide use at a large academic center. The template included the statement "There are no coronary artery calcifications." All noncardiac, noncontrast chest CT examinations reported over 3 days, 1 month after template implementation (structured template group), and from a 3-day period 1 year prior (control group) were retrospectively collected. Final radiology reports were reviewed and designated positive or negative for coronary calcifications. CT images were reviewed in consensus by 2 radiologists, who scored each case for the presence or absence of coronary calcifications, blinded to the original report. Statistical analysis was performed using Pearson χ(2) and Fisher exact tests. Sixty-five percent (69 of 106) of structured template group and 58% (62 of 106) of control group cases had coronary calcifications. Reports from the structured template group were more likely to correctly state the presence or absence of coronary atherosclerosis compared with those from the control group (96.2% vs 85.8%; odds ratio, 4.2; 95% confidence interval, 1.3-13.1; P = .008). Structured template group reports were less likely to be falsely negative compared with control group reports (3.8% vs 11.7%; odds ratio, 3.4; 95% confidence interval, 1.0-10.8; P = .03). Implementing a structured reporting template improves reporting accuracy of coronary calcifications. Copyright © 2015 American College of Radiology. Published by Elsevier Inc. All rights reserved.
Hill, Micah J; Levens, Eric D; Levy, Gary; Ryan, Mary E; Csokmay, John M; DeCherney, Alan H; Whitcomb, Brian W
2012-05-01
To evaluate the effect of recombinant LH in assisted reproduction technology (ART) cycles in patients of advanced reproductive age. A systematic review and meta-analysis. Published randomized controlled clinical trials comparing recombinant LH plus recombinant FSH versus recombinant FSH only in patients of advanced reproductive age. Patients 35 years and older undergoing assisted reproduction. Recombinant LH plus recombinant FSH controlled ovarian hyperstimulation (COH) versus recombinant FSH stimulation only in assisted reproduction cycles. Implantation and clinical pregnancy. Seven trials were identified that met inclusion criteria and comprised 902 assisted reproduction technology cycles. No differences in serum E(2) on the day of hCG administration were reported in any trials. Two trials reported lower oocyte yield and one trial reported lower metaphase II oocyte yield in the recombinant LH-supplemented group. One trial reported higher fertilization rates in the recombinant LH-supplemented group. In a fixed effect model, implantation was higher in the recombinant LH-supplemented group (odds ratio 1.36, 95% confidence interval 1.05-1.78). Similarly, clinical pregnancy was increased in the recombinant LH-supplemented group (odds ratio 1.37, 95% confidence interval 1.03-1.83). The addition of recombinant LH to ART cycles may improve implantation and clinical pregnancy in patients of advanced reproductive age. Copyright © 2012 American Society for Reproductive Medicine. All rights reserved.
Valle, Adolfo Martinez
2009-01-01
Background Examining the association between social inequality and health is not new. However, there is little empirical evidence of this association in the Latin American literature, much less from the Mexican scholars. Its research, including the one conducted in Mexico, has mostly followed a theoretical approach and has not been able to provide strong empirical evidence of their important theoretical and conceptual contributions, mainly because reliable, complete and valid data are unavailable. Methods To empirically examine the gradient effect of social class on self-rated health in Mexico, a secondary cross-sectional mixed-level analysis was designed. Using individual level data from the Second National Health Survey (ENSA II), social class categories were specified following a stratification approach according to the occupation and education indicators available from ENSA II. Two types of categories were made, one for t urban and one for the rural labor force. Two indicators of perceived health status were used as health outcomes: self-assessed health and reported morbidity. Furthermore, the marginality index, an indicator of relative deprivation was used to examine its contextual effect at the state and regional level. The analysis was conducted using logistic multivariate models. Results The cross-sectional analysis showed a gradient effect of social class for good assessed-health. Relative to the low urban class, the odds ratio (OR) for a good perception of health for individuals belonging to the high urban class was 2.9 (95% confidence interval: 2.1–3.9). The OR for the middle high class was 2.8 (95% confidence interval: 2.4–3.4), while the OR for the middle low class was 1.8 (95% confidence interval: 1.6–2.1). However, for the rural labour force an OR of 1.5 was only significant between the high class who considered their health as good relative to the low class (95% confidence interval: 1.02–2.2). At the aggregate level, the results also showed individuals living in deprived regions were less likely to report their health as good than individuals living in relatively less deprived ones, OR = 0.6 (95% confidence interval: 0.4–0.7). Conclusion Overall, the findings of this study provided empirical evidence that social inequality negatively influences health through a differential exposure and an unequal distribution of resources across the class spectrum: the lower the social class, the poorer the perception of health. The results also showed that living in more deprived regions had a further negative effect on health. From a policy perspective, the gradient effects of social class suggest that non-targeted policies should be designed to address both material conditions at the individual level as well as deprived living conditions at higher levels of aggregation to improve health across the social spectrum. PMID:19236708
Rocco, Paolo; Cilurzo, Francesco; Minghetti, Paola; Vistoli, Giulio; Pedretti, Alessandro
2017-10-01
The data presented in this article are related to the article titled "Molecular Dynamics as a tool for in silico screening of skin permeability" (Rocco et al., 2017) [1]. Knowledge of the confidence interval and maximum theoretical value of the correlation coefficient r can prove useful to estimate the reliability of developed predictive models, in particular when there is great variability in compiled experimental datasets. In this Data in Brief article, data from purposely designed numerical simulations are presented to show how much the maximum r value is worsened by increasing the data uncertainty. The corresponding confidence interval of r is determined by using the Fisher r → Z transform.
Charan, J; Saxena, D
2014-01-01
Biased negative studies not only reflect poor research effort but also have an impact on 'patient care' as they prevent further research with similar objectives, leading to potential research areas remaining unexplored. Hence, published 'negative studies' should be methodologically strong. All parameters that may help a reader to judge validity of results and conclusions should be reported in published negative studies. There is a paucity of data on reporting of statistical and methodological parameters in negative studies published in Indian Medical Journals. The present systematic review was designed with an aim to critically evaluate negative studies published in prominent Indian Medical Journals for reporting of statistical and methodological parameters. Systematic review. All negative studies published in 15 Science Citation Indexed (SCI) medical journals published from India were included in present study. Investigators involved in the study evaluated all negative studies for the reporting of various parameters. Primary endpoints were reporting of "power" and "confidence interval." Power was reported in 11.8% studies. Confidence interval was reported in 15.7% studies. Majority of parameters like sample size calculation (13.2%), type of sampling method (50.8%), name of statistical tests (49.1%), adjustment of multiple endpoints (1%), post hoc power calculation (2.1%) were reported poorly. Frequency of reporting was more in clinical trials as compared to other study designs and in journals having impact factor more than 1 as compared to journals having impact factor less than 1. Negative studies published in prominent Indian medical journals do not report statistical and methodological parameters adequately and this may create problems in the critical appraisal of findings reported in these journals by its readers.
Likelihood-Based Confidence Intervals in Exploratory Factor Analysis
ERIC Educational Resources Information Center
Oort, Frans J.
2011-01-01
In exploratory or unrestricted factor analysis, all factor loadings are free to be estimated. In oblique solutions, the correlations between common factors are free to be estimated as well. The purpose of this article is to show how likelihood-based confidence intervals can be obtained for rotated factor loadings and factor correlations, by…
Statistical inference for remote sensing-based estimates of net deforestation
Ronald E. McRoberts; Brian F. Walters
2012-01-01
Statistical inference requires expression of an estimate in probabilistic terms, usually in the form of a confidence interval. An approach to constructing confidence intervals for remote sensing-based estimates of net deforestation is illustrated. The approach is based on post-classification methods using two independent forest/non-forest classifications because...
Results from a NIST-EPA Interagency Agreement on Understanding Systematic Measurement Error in Thermal-Optical Analysis for PM Black Carbon Using Response Surfaces and Surface Confidence Intervals will be presented at the American Association for Aerosol Research (AAAR) 24th Annu...
The impact of effort-reward imbalance on quality of life among Japanese working men.
Watanabe, Mayumi; Tanaka, Katsutoshi; Aratake, Yutaka; Kato, Noritada; Sakata, Yumi
2008-07-01
Health-related quality of life (HRQL) is an important measure of health outcome in working and healthy populations. Here, we investigated the impact of effort-reward imbalance (ERI), a representative work-stress model, on HRQL of Japanese working men. The study targeted 1,096 employees from a manufacturing plant in Japan. To assess HRQL and ERI, participants were surveyed using the Japanese version of the Short-Form 8 Health Survey (SF-8) and effort-reward imbalance model. Of the 1,096 employees, 1,057 provided valid responses to the questionnaire. For physical summary scores, the adjusted effort-reward imbalance odds ratios of middle vs. bottom and top vs. bottom tertiles were 0.24 (95% confidence interval, 0.08-0.70) and 0.09 (95% confidence interval, 0.03-0.28), respectively. For mental summary scores, ratios were 0.21 (95% confidence interval, 0.07-0.63) and 0.07 (95% confidence interval, 0.02-0.25), respectively. These findings demonstrate that effort-reward imbalance is independently associated with HRQL among Japanese employees.
Reinhardt Pedersen, C; Madsen, M
2002-11-01
To study the association between parents' labour market participation and children's health and wellbeing. Parent reported data on health and wellbeing among their children from the survey Health and welfare among children and adolescents in the Nordic countries, 1996. A cross sectional study of random samples of children and their families in five Nordic countries (Denmark, Finland, Iceland, Norway, and Sweden). A total of 10 317 children aged 2-17 years. Children in families with no parents employed in the past six months had higher prevalence of recurrent psychosomatic symptoms (odds ratio 1.67, 95% confidence intervals 1.16 to 2.40), chronic illness (odds ratio 1.35, 95% confidence intervals 1.00 to 1.84), and low wellbeing (odds ratio 1.47, 95% confidence intervals 1.12 to 1.94). Social class, family type, parents' immigrant status, gender and age of the child, respondent, and country were included as confounders. When social class, family type and the parents' immigrant status (one or more born in the Nordic country versus both born elsewhere) were introduced into the model, the odds ratios were reduced but were still statistically significant. Health outcomes and parents' labour market participation were associated in all five countries. Children in families with no parents employed in the past six months had higher prevalence of ill health and low wellbeing in the five Nordic countries despite differences in employment rates and social benefits.
Socioeconomic inequality and peripheral artery disease prevalence in US adults.
Pande, Reena L; Creager, Mark A
2014-07-01
Lower socioeconomic status is associated with cardiovascular disease. We sought to determine whether there is a higher prevalence of peripheral artery disease (PAD) in individuals with lower socioeconomic status. We analyzed data from the National Health and Nutrition Examination Survey 1999 to 2004. PAD was defined based on an ankle.brachial index .0.90. Measures of socioeconomic status included poverty.income ratio,a ratio of self-reported income relative to the poverty line, and attained education level. Of 6791 eligible participants,overall weighted prevalence of PAD was 5.8% (SE, 0.3). PAD prevalence was significantly higher in individuals with low income and lower education. Individuals in the lowest of the 6 poverty.income ratio categories had more than a2-fold increased odds of PAD compared with those in the highest poverty-income ratio category (odds ratio, 2.69; 95%confidence interval, 1.80.4.03; P<0.0001). This association remained significant even after multivariable adjustment(odds ratio, 1.64; 95% confidence interval, 1.04.2.6; P=0.034). Lower attained education level also associated with higher PAD prevalence (odds ratio, 2.8; 95% confidence interval, 1.96.4.0; P<0.0001) but was no longer significant after multivariable adjustment. Low income and lower attained education level are associated with PAD in US adults. These data suggest that individuals of lower socioeconomic status remain at high risk and highlight the need for education and advocacy efforts focused on these at-risk populations.
Briel, Matthias; Studer, Marco; Glass, Tracy R; Bucher, Heiner C
2004-10-15
To assess if lipid-lowering interventions (statins, fibrates, resins, n-3 fatty acids, diet) prevent nonfatal and fatal strokes in patients with and without coronary heart disease. We systematically searched the literature up to August 2002 to retrieve all randomized controlled trials of lipid-lowering interventions that reported nonfatal and fatal stroke and mortality data. The search yielded 65 trials with 200,607 patients for a meta-analysis to determine whether treatment effects differed between types of lipid-lowering interventions and between patient samples with and without coronary heart disease. The risk ratio for nonfatal and fatal stroke for statins as compared with control interventions was 0.82 (95% confidence interval [CI]: 0.76 to 0.90). The corresponding risk ratios for statins as compared with control were 0.75 (95% CI: 0.65 to 0.87) for patients with coronary heart disease and 0.77 (95% CI: 0.62 to 0.95) for those without coronary heart disease. The confidence intervals of risk ratios for nonfatal and fatal stroke associated with fibrates, resins, n-3 fatty acids, and diet all included 1, as did the confidence intervals for these interventions in patients with and without coronary heart disease. Weighted meta-regression analysis suggested a stronger association of stroke reduction with statin treatment than with the extent of cholesterol reduction. This meta-analysis suggests that statins reduce the incidence of stroke in patients with and without coronary heart disease.
Wang, JianLi; Patten, Scott B.; Currie, Shawn; Sareen, Jitender; Schmitz, Norbert
2012-01-01
To investigate the relation between work environmental factors and the risk of major depressive disorder (MDD) over 1 year, the authors conducted a population-based longitudinal study of randomly selected employees in Alberta, Canada (January 2008 to November 2011). Participants without a current or lifetime diagnosis of MDD at baseline (n = 2,752) were followed for 1 year. MDD was assessed using the World Health Organization’s Composite International Diagnostic Interview-Auto 2.1. The overall 1-year incidence of MDD was 3.6% (95% confidence interval: 2.8, 4.6); it was 2.9% (95% confidence interval: 1.9, 4.2) in men and 4.5% (95% confidence interval: 3.3, 6.2) in women. The relations between work environmental factors and MDD differed by sex. In men, high job strain increased the risk of MDD in those who worked 35–40 hours per week; job insecurity and family-to-work conflict were predictive of MDD. Women who worked 35–40 hours per week and reported job insecurity, a high effort-reward imbalance, and work-to-family conflict were at a higher risk of developing MDD. Job strain, effort-reward imbalance, job insecurity, and work-to-family conflicts are important risk factors for the onset of MDD and should be targets of primary prevention. However, these work environmental factors appear to operate differently in men and in women. PMID:22556191
Schweiger, Regev; Fisher, Eyal; Rahmani, Elior; Shenhav, Liat; Rosset, Saharon; Halperin, Eran
2018-06-22
Estimation of heritability is an important task in genetics. The use of linear mixed models (LMMs) to determine narrow-sense single-nucleotide polymorphism (SNP)-heritability and related quantities has received much recent attention, due of its ability to account for variants with small effect sizes. Typically, heritability estimation under LMMs uses the restricted maximum likelihood (REML) approach. The common way to report the uncertainty in REML estimation uses standard errors (SEs), which rely on asymptotic properties. However, these assumptions are often violated because of the bounded parameter space, statistical dependencies, and limited sample size, leading to biased estimates and inflated or deflated confidence intervals (CIs). In addition, for larger data sets (e.g., tens of thousands of individuals), the construction of SEs itself may require considerable time, as it requires expensive matrix inversions and multiplications. Here, we present FIESTA (Fast confidence IntErvals using STochastic Approximation), a method for constructing accurate CIs. FIESTA is based on parametric bootstrap sampling, and, therefore, avoids unjustified assumptions on the distribution of the heritability estimator. FIESTA uses stochastic approximation techniques, which accelerate the construction of CIs by several orders of magnitude, compared with previous approaches as well as to the analytical approximation used by SEs. FIESTA builds accurate CIs rapidly, for example, requiring only several seconds for data sets of tens of thousands of individuals, making FIESTA a very fast solution to the problem of building accurate CIs for heritability for all data set sizes.
Wege, Natalia; Angerer, Peter; Li, Jian
2017-08-11
Unemployment and job insecurity have been reported to be associated with a higher risk of depression. The purpose of this study was to evaluate the separate and combined effects of lifetime unemployment experience and job insecurity on the incidence of depression in an unselected working population in Germany. Data from the German Socio-Economic Panel (GSOEP) study were used, as was a final sample of those currently employed, with complete data at baseline (2009) and follow-up (2011) restricted to those free of depression in 2009 ( n = 7073). Poisson regression analysis was applied to test the prospective associations between unemployment, job insecurity, and a two-year incident of depression. Results showed that the experience of unemployment and perceived job insecurity were significantly associated with a higher risk of depression during the two-year follow-up (risk ratios 1.64; 95% confidence intervals (1.16, 2.31) and risk ratios 1.48; 95% confidence intervals (1.13, 1.92), respectively). Notably, the strongest risk was observed among participants with insecure jobs and past long-term unemployment (risk ratios 2.15; 95% confidence intervals (1.32; 3.52)). In conclusion, even during employment, the experience of lifetime unemployment led to a higher risk of depression. The combination of previous unemployment experience and anticipated job insecurity increased the risk of developing depression. Results support health promotion with special emphasis on unemployment and precarious working conditions.
Pope, Daniel P; Mishra, Vinod; Thompson, Lisa; Siddiqui, Amna Rehana; Rehfuess, Eva A; Weber, Martin; Bruce, Nigel G
2010-01-01
Exposure to indoor air pollution from solid fuel use (IAP) has been linked to approximately 1.5 million annual deaths (World Health Organization (http://www.who.int/indoorair/publications/fuelforlife/en/index.html)) due to acute lower respiratory infections in children <5 years of age and chronic obstructive lung disease and lung cancer in adults. Emerging evidence suggests that IAP increases the risk of other conditions, including adverse pregnancy outcomes. To establish the relation of IAP with birth weight and stillbirth, systematic reviews with meta-analyses were conducted. Studies reporting outcomes of mean birth weight, percentage of low birth weight (LBW; <2,500 g), and/or stillbirth and assessing IAP were identified. Five LBW studies (of 982) and 3 stillbirth studies (of 171) met inclusion criteria for the reviews. Fixed-effect meta-analyses (I(2) = 0%) found that IAP was associated with increased risk of percentage LBW (odds ratio = 1.38, 95% confidence interval: 1.25, 1.52) and stillbirth (odds ratio = 1.51, 95% confidence interval: 1.23, 1.85) and reduced mean birth weight (-95.6 g, 95% confidence interval: -68.5, -124.7). Evidence from secondhand smoke, ambient air pollution, and animal studies--and suggested plausible mechanisms--substantiate these associations. Because a majority of pregnant women in developing countries, where rates of LBW and stillbirth are high, are heavily exposed to IAP, increased relative risk translates into substantial population attributable risks of 21% (LBW) and 26% (stillbirth).
Socioeconomic position and education in patients with coeliac disease.
Olén, Ola; Bihagen, Erik; Rasmussen, Finn; Ludvigsson, Jonas F
2012-06-01
Socioeconomic position and education are strongly associated with several chronic diseases, but their relation to coeliac disease is unclear. We examined educational level and socioeconomic position in patients with coeliac disease. We identified 29,096 patients with coeliac disease through biopsy reports (defined as Marsh 3: villous atrophy) from all Swedish pathology departments (n=28). Age- and sex-matched controls were randomly sampled from the Swedish Total Population Register (n=145,090). Data on level of education and socioeconomic position were obtained from the Swedish Education Register and the Occupational Register. We calculated odds ratios for the risk of having coeliac disease based on socioeconomic position according to the European Socioeconomic Classification (9 levels) and education. Compared to individuals with high socioeconomic position (level 1 of 9) coeliac disease was less common in the lowest socioeconomic stratum (routine occupations=level 9 of 9: adjusted odds ratio=0.89; 95% confidence interval=0.84-0.94) but not less common in individuals with moderately low socioeconomic position: (level 7/9: adjusted odds ratio=0.96; 95% confidence interval=0.91-1.02; and level 8/9: adjusted odds ratio=0.99; 95% confidence interval=0.93-1.05). Coeliac disease was not associated with educational level. In conclusion, diagnosed coeliac disease was slightly less common in individuals with low socioeconomic position but not associated with educational level. Coeliac disease may be unrecognised in individuals of low socioeconomic position. Copyright © 2012 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.
Kishore, Amit; Vail, Andy; Majid, Arshad; Dawson, Jesse; Lees, Kennedy R; Tyrrell, Pippa J; Smith, Craig J
2014-02-01
Atrial fibrillation (AF) confers a high risk of recurrent stroke, although detection methods and definitions of paroxysmal AF during screening vary. We therefore undertook a systematic review and meta-analysis to determine the frequency of newly detected AF using noninvasive or invasive cardiac monitoring after ischemic stroke or transient ischemic attack. Prospective observational studies or randomized controlled trials of patients with ischemic stroke, transient ischemic attack, or both, who underwent any cardiac monitoring for a minimum of 12 hours, were included after electronic searches of multiple databases. The primary outcome was detection of any new AF during the monitoring period. We prespecified subgroup analysis of selected (prescreened or cryptogenic) versus unselected patients and according to duration of monitoring. A total of 32 studies were analyzed. The overall detection rate of any AF was 11.5% (95% confidence interval, 8.9%-14.3%), although the timing, duration, method of monitoring, and reporting of diagnostic criteria used for paroxysmal AF varied. Detection rates were higher in selected (13.4%; 95% confidence interval, 9.0%-18.4%) than in unselected patients (6.2%; 95% confidence interval, 4.4%-8.3%). There was substantial heterogeneity even within specified subgroups. Detection of AF was highly variable, and the review was limited by small sample sizes and marked heterogeneity. Further studies are required to inform patient selection, optimal timing, methods, and duration of monitoring for detection of AF/paroxysmal AF.
Söderström, Lovisa; Perez-Vicente, Raquel; Juárez, Sol; Merlo, Juan
2013-01-01
A recent population-based, longitudinal study from Finland observed a dose-response association between smoking during pregnancy (SDP) and use of psychotropic medications in exposed children and young adults. However, this association may be confounded by unmeasured familial characteristics related to both SDP and offspring mental health. Consequently, we aim to investigate the effect of SDP by means of a sibling design that to some extent allows controlling for unknown environmental and genetic confounders. Using the Swedish Medical Birth Register (1987-1993), which was linked to the Swedish Prescribed Drugs Register (July 2005-December 2008), we investigated 579,543 children and among them 39, 007 were discordant for use of psychotropic medication and 4,021 siblings discordant for both use of psychotropic medication and for smoking exposure. Replicating the Finnish study using traditional logistic regression methods we found an association between exposure to ≥10 cigarettes per day during pregnancy and psychotropic drug use (odds ratio = 1.61, 95% confidence interval 1.56, 1.66). Similar in size to the association reported from Finland (odds ratio = 1.63; 95% confidence interval 1.53, 1.74). However, in the adjusted sibling analysis using conditional logistic regression, the association was considerably reduced (odds ratio 1.22; 95% confidence interval 1.08, 1.38). Preventing smoking is of major public health importance. However, SDP per se appears to have less influence on offspring psychotropic drug use than previously suggested.
Relationships between dog ownership and physical activity in postmenopausal women.
Garcia, David O; Wertheim, Betsy C; Manson, JoAnn E; Chlebowski, Rowan T; Volpe, Stella L; Howard, Barbara V; Stefanick, Marcia L; Thomson, Cynthia A
2015-01-01
Positive associations between dog ownership and physical activity in older adults have been previously reported. The objective of this study was to examine cross-sectional associations between dog ownership and physical activity measures in a well-characterized, diverse sample of postmenopausal women. Analyses included 36,984 dog owners (mean age: 61.5years), and 115,645 non-dog owners (mean age: 63.9years) enrolled in a clinical trial or the observational study of the Women's Health Initiative between 1993 and 1998. Logistic regression models were used to test for associations between dog ownership and physical activity, adjusted for potential confounders. Owning a dog was associated with a higher likelihood of walking ≥150min/wk (Odds Ratio, 1.14; 95% Confidence Interval, 1.10-1.17) and a lower likelihood of being sedentary ≥8h/day (Odds Ratio, 0.86; 95% Confidence Interval, 0.83-0.89) as compared to not owning a dog. However, dog owners were less likely to meet ≥7.5MET-h/wk of total physical activity as compared to non-dog owners (Odds Ratio, 1.03; 95% Confidence Interval, 1.00-1.07). Dog ownership is associated with increased physical activity in older women, particularly among women living alone. Health promotion efforts aimed at older adults should highlight the benefits of regular dog walking for both dog owners and non-dog owners. Copyright © 2014 Elsevier Inc. All rights reserved.
Vaccination Confidence and Parental Refusal/Delay of Early Childhood Vaccines.
Gilkey, Melissa B; McRee, Annie-Laurie; Magnus, Brooke E; Reiter, Paul L; Dempsey, Amanda F; Brewer, Noel T
2016-01-01
To support efforts to address parental hesitancy towards early childhood vaccination, we sought to validate the Vaccination Confidence Scale using data from a large, population-based sample of U.S. parents. We used weighted data from 9,354 parents who completed the 2011 National Immunization Survey. Parents reported on the immunization history of a 19- to 35-month-old child in their households. Healthcare providers then verified children's vaccination status for vaccines including measles, mumps, and rubella (MMR), varicella, and seasonal flu. We used separate multivariable logistic regression models to assess associations between parents' mean scores on the 8-item Vaccination Confidence Scale and vaccine refusal, vaccine delay, and vaccination status. A substantial minority of parents reported a history of vaccine refusal (15%) or delay (27%). Vaccination confidence was negatively associated with refusal of any vaccine (odds ratio [OR] = 0.58, 95% confidence interval [CI], 0.54-0.63) as well as refusal of MMR, varicella, and flu vaccines specifically. Negative associations between vaccination confidence and measures of vaccine delay were more moderate, including delay of any vaccine (OR = 0.81, 95% CI, 0.76-0.86). Vaccination confidence was positively associated with having received vaccines, including MMR (OR = 1.53, 95% CI, 1.40-1.68), varicella (OR = 1.54, 95% CI, 1.42-1.66), and flu vaccines (OR = 1.32, 95% CI, 1.23-1.42). Vaccination confidence was consistently associated with early childhood vaccination behavior across multiple vaccine types. Our findings support expanding the application of the Vaccination Confidence Scale to measure vaccination beliefs among parents of young children.
Salminen, Marika; Vahlberg, Tero; Räihä, Ismo; Niskanen, Leo; Kivelä, Sirkka-Liisa; Irjala, Kerttu
2015-05-01
To analyze whether sex hormone levels predict the incidence of type2 diabetes among elderly Finnish men. This was a prospective population-based study, with a 9-year follow up period. The study population in the municipality of Lieto, Finland, consisted of elderly (age ≥64 years) men free of type 2 diabetes at baseline in 1998-1999 (n = 430). Body mass index and cardiovascular disease-adjusted hazard ratios and their 95% confidence intervals for type 2 diabetes predicted by testosterone, free testosterone, sex hormone-binding globulin, luteinizing hormone, and testosterone/luteinizing hormone were estimated. A total of 30 new cases of type 2 diabetes developed during the follow-up period. After adjustment, only higher levels of testosterone (hazard ratio for one-unit increase 0.93, 95% confidence interval 0.87-0.99, P = 0.020) and free testosterone (hazard ratio for 10-unit increase 0.96, 95% confidence interval 0.91-1.00, P = 0.044) were associated with a lower risk of incident type 2 diabetes during the follow up. These associations (0.94, 95% confidence interval 0.87-1.00, P = 0.050 and 0.95, 95% confidence interval 0.90-1.00, P = 0.035, respectively) persisted even after additional adjustment of sex hormone-binding globulin. Higher levels of testosterone and free testosterone independently predicted a reduced risk of type 2 diabetes in the elderly men. © 2014 Japan Geriatrics Society.
Hosen, Md Bayejid; Islam, Jahidul; Salam, Md Abdus; Islam, Md Fakhrul; Hawlader, M Zakir Hossain; Kabir, Yearul
2015-03-01
To investigate the association between the three most common single nucleotide polymorphisms of the N-acetyltransferase 2 gene together with cigarette smoking and the risk of developing bladder cancer and its aggressiveness. A case-control study on 102 bladder cancer patients and 140 control subjects was conducted. The genomic DNA was extracted from peripheral white blood cells and N-acetyltransferase 2 alleles were differentiated by polymerase chain reaction-based restriction fragment length polymorphism methods. Bladder cancer risk was estimated as odds ratio and 95% confidence interval using binary logistic regression models adjusting for age and gender. Overall, N-acetyltransferase 2 slow genotypes were associated with bladder cancer risk (odds ratio=4.45; 95% confidence interval=2.26-8.77). The cigarette smokers with slow genotypes were found to have a sixfold increased risk to develop bladder cancer (odds ratio=6.05; 95% confidence interval=2.23-15.82). Patients with slow acetylating genotypes were more prone to develop high-grade (odds ratio=6.63; 95% confidence interval=1.15-38.13; P<0.05) and invasive (odds ratio=10.6; 95% confidence interval=1.00-111.5; P=0.05) tumor. N-acetyltransferase 2 slow genotype together with tobacco smoking increases bladder cancer risk. Patients with N-acetyltransferase 2 slow genotypes were more likely to develop a high-grade and invasive tumor. N-acetyltransferase 2 slow genotype is an important genetic determinant for bladder cancer in Bangladesh population. © 2014 Wiley Publishing Asia Pty Ltd.
Ruanpeng, Darin; Ungprasert, Patompong; Sangtian, Jutarat; Harindhanavudhi, Tasma
2017-09-01
Sodium-glucose cotransporter 2 (SGLT2) inhibitors could potentially alter calcium and phosphate homeostasis and may increase the risk of bone fracture. The current meta-analysis was conducted to investigate the fracture risk among patients with type 2 diabetes mellitus treated with SGLT2 inhibitors. Randomized controlled trials that compared the efficacy of SGLT2 inhibitors to placebo were identified. The risk ratios of fracture among patients who received SGLT2 inhibitors versus placebo were extracted from each study. Pooled risk ratios and 95% confidence intervals were calculated using a random-effect, Mantel-Haenszel analysis. A total of 20 studies with 8286 patients treated with SGLT2 inhibitors were included. The pooled risk ratio of bone fracture in patients receiving SGLT2 inhibitors versus placebo was 0.67 (95% confidence interval, 0.42-1.07). The pooled risk ratio for canagliflozin, dapagliflozin, and empagliflozin was 0.66 (95% confidence interval, 0.37-1.19), 0.84 (95% confidence interval, 0.22-3.18), and 0.57 (95% confidence interval, 0.20-1.59), respectively. Increased risk of bone fracture among patients with type 2 diabetes mellitus treated with SGLT2 inhibitors compared with placebo was not observed in this meta-analysis. However, the results were limited by short duration of treatment/follow-up and low incidence of the event of interest. Copyright © 2017 John Wiley & Sons, Ltd.
ERIC Educational Resources Information Center
Zhang, Zhiyong; Yuan, Ke-Hai
2016-01-01
Cronbach's coefficient alpha is a widely used reliability measure in social, behavioral, and education sciences. It is reported in nearly every study that involves measuring a construct through multiple items. With non-tau-equivalent items, McDonald's omega has been used as a popular alternative to alpha in the literature. Traditional estimation…
ERIC Educational Resources Information Center
Zhang, Zhiyong; Yuan, Ke-Hai
2016-01-01
Cronbach's coefficient alpha is a widely used reliability measure in social, behavioral, and education sciences. It is reported in nearly every study that involves measuring a construct through multiple items. With non-tau-equivalent items, McDonald's omega has been used as a popular alternative to alpha in the literature. Traditional estimation…
Vaag, Jonas; Saksvik-Lehouillier, Ingvild; Bjørngaard, Johan Håkon; Bjerkeset, Ottar
2016-01-01
Sleep problems are reported as common among performing artists and musicians. However, epidemiological research comparing musicians to different groups of the general population is lacking. For this study, 4,168 members of the Norwegian Musician's Union were invited to an online survey regarding work and health. Of the 2,121 (51%) respondents, 1,607 were active performing musicians. We measured prevalence of insomnia symptoms using the Bergen Insomnia Scale (BIS), and compared this sample to a representative sample of the general Norwegian population (n = 2,645). Overall, musicians had higher prevalence of insomnia symptoms compared to the general population (Prevalence Difference 6.9, 95% Confidence Interval 3.9-10.0). Item response analysis showed that this difference was mainly explained by nonrestorative sleep and dissatisfaction with sleep among musicians. An additional analysis, comparing musicians to the general Norwegian workforce (n = 8,518) on sleep difficulties, confirmed this tendency (Prevalence Difference 6.2, 95% Confidence Interval 4.3-8.1). Musicians performing classical, contemporary, rock, and country music reported the highest prevalence of insomnia, and these genres might be of special interest when developing preventative measures, treatment strategies, and further research on sleep difficulties among musicians.
A Profile of Indian Health Service Emergency Departments.
Bernard, Kenneth; Hasegawa, Kohei; Sullivan, Ashley; Camargo, Carlos
2017-06-01
The Indian Health Service provides health care to eligible American Indians and Alaskan Natives. No published data exist on emergency services offered by this unique health care system. We seek to determine the characteristics and capabilities of Indian Health Service emergency departments (EDs). All Indian Health Service EDs were surveyed about demographics and operational characteristics for 2014 with the National Emergency Department Inventory survey (available at http://www.emnet-nedi.org/). Of the forty eligible sites, there were 34 respondents (85% response rate). Respondents reported a total of 637,523 ED encounters, ranging from 521 to 63,200 visits per site. Overall, 85% (95% confidence interval 70% to 94%) had continuous physician coverage. Of all physicians staffing the ED, a median of 13% (interquartile range 0% to 50%) were board certified or board prepared in emergency medicine. Overall, 50% (95% confidence interval 34% to 66%) of respondents reported that their ED was operating over capacity. Indian Health Service EDs varied widely in visit volume, with many operating over capacity. Most were not staffed by board-certified or -prepared emergency physicians. Most lacked access to specialty consultation and telemedicine capabilities. Copyright © 2016 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.
Can the Internet be used to reach parents for family-based childhood obesity interventions?
Hohman, Katherine H; Price, Sarah N; Sonneville, Kendrin; Rifas-Shiman, Sheryl L; Gortmaker, Steven L; Gillman, Matthew W; Taveras, Elsie M
2012-04-01
This study aimed to identify socioeconomic correlates of computer/Internet use among parents of overweight preschool-aged children. A total of 470 baseline participants in a trial to prevent obesity in children 2 to 6.9 years old with body mass index ≥ 95th percentile or 85th to 95th percentile with one overweight parent were studied. Interviews with parents used Health Information National Trends Survey questions. Overall, 94% of the participants had home computers and 93% reported Internet usage. In adjusted models, parents with ≤ college degree (odds ratio = 4.8; 95% confidence interval = 1.2-18.3) or with household income ≤$50,000 (odds ratio = 7.6; 95% confidence interval = 2.2-26.8) had decreased likelihood of computer ownership. Of parents who reported going online, 63% used Internet to look for health/medical information for themselves and 42% for their children. Parents with ≤ a college degree or with body mass index <25 kg/m(2) were less likely to use Internet. Results support using the Internet for early childhood obesity prevention with enhanced outreach efforts for low socioeconomic status families.
Crosby, Richard A; Mena, Leandro; Salazar, Laura F; Hardin, James W; Brown, Tim; Vickers Smith, Rachel
2018-03-01
To test the efficacy of a single-session, clinic-based intervention designed to promote condom use among young black men who have sex with men (YBMSM). Six hundred YBMSM were enrolled in a randomized controlled trial, using a 12-month observation period. An intent-to-treat analysis was performed, with multiple imputation for missing data. Compared with the reference group, human immunodeficiency virus (HIV)-infected men in the intervention group had 64% greater odds of reporting consistent condom use for anal receptive sex over 12 months (estimated odds ratio, 1.64; 95% confidence interval, 1.23-2.17, P = 0.001). Also, compared with the reference group, HIV-uninfected men in the intervention group had more than twice the odds of reporting consistent condom use for anal receptive sex over 12 months (estimated odds ratio, 2.14; 95% confidence interval, 1.74-2.63, P < 0.001). Significant intervention effects relative to incident sexually transmitted diseases were not observed. A single-session, clinic-based, intervention may help protect HIV-uninfected YBMSM against HIV acquisition and HIV-infected YBMSM from transmitting the virus to insertive partners.
Lu, Chun-Yi; Chang, Luan-Yin; Shao, Pei-Lan; Suryakiran, Pemmaraju Venkata; Han, Htay-Htay; Huang, Li-Min
2013-09-01
This Phase-IV study evaluated the human rotavirus (RV) vaccine Rotarix (RIX4414) to provide additional local clinical data to the Taiwan Food and Drug Association (NCT01198769). Healthy infants aged 6-12 weeks who were given a hepatitis B immunoglobulin (HBIg) dose after birth, received two doses of RIX4414 (0, 2-month schedule). Anti-RV IgA antibody concentrations were measured using ELISA. A total of 15 infants were enrolled, and included in the according-to-protocol cohort. The anti-RV IgA antibody seroconversion rate 2 months post-Dose 2 was 100% (95% confidence interval = 78.2-100) and the geometric mean concentration was 254.7 U/ml (95% confidence interval = 145.0-447.7). Two episodes of gastroenteritis were reported, and one stool sample was tested for RV, which was negative. No fatal serious adverse events were reported during the study period between November 2010 and April 2011. The two-dose regimen of RIX4414 was highly immunogenic and safe when administered to healthy Taiwanese infants who received a HBIg dose after birth. NCT01198769. Copyright © 2012. Published by Elsevier B.V.
Albumin treatment regimen for type 1 hepatorenal syndrome: a dose-response meta-analysis.
Salerno, Francesco; Navickis, Roberta J; Wilkes, Mahlon M
2015-11-25
Recommended treatment for type 1 hepatorenal syndrome consists of albumin and vasoconstrictor. The optimal albumin dose remains poorly characterized. This meta-analysis aimed to determine the impact of albumin dose on treatment outcomes. Clinical studies of type 1 hepatorenal syndrome treatment with albumin and vasoconstrictor were sought. Search terms included: hepatorenal syndrome; albumin; vasoconstrictor; terlipressin; midodrine; octreotide; noradrenaline; and norepinephrine. A meta-analysis was performed of hepatorenal syndrome reversal and survival in relation to albumin dose. Nineteen clinical studies with 574 total patients were included, comprising 8 randomized controlled trials, 8 prospective studies and 3 retrospective studies. The pooled percentage of patients achieving hepatorenal syndrome reversal was 49.5% (95% confidence interval, 40.0-59.1%). Increments of 100 g in cumulative albumin dose were accompanied by significantly increased survival (hazard ratio, 1.15; 95% confidence interval, 1.02-1.31; p = 0.023). A non-significant increase of similar magnitude in hepatorenal syndrome reversal was also observed (odds ratio, 1.15; 95% confidence interval, 0.97-1.37; p = 0.10). Expected survival rates at 30 days among patients receiving cumulative albumin doses of 200, 400 and 600 g were 43.2% (95% confidence interval, 36.4-51.3%), 51.4% (95% confidence interval, 46.3-57.1%) and 59.0% (95% confidence interval, 51.9-67.2), respectively. Neither survival nor hepatorenal syndrome reversal was significantly affected by vasoconstrictor dose or type, treatment duration, age, baseline serum creatinine, bilirubin or albumin, baseline mean arterial pressure, or study design, size or time period. This meta-analysis suggests a dose-response relationship between infused albumin and survival in patients with type 1 hepatorenal syndrome. The meta-analysis provides the best current evidence on the potential role of albumin dose selection in improving outcomes of treatment for type 1 HRS and furnishes guidance for the design of future dose-ranging studies.
Corona-Rivera, Jorge Román; Bobadilla-Morales, Lucina; Corona-Rivera, Alfredo; Peña-Padilla, Christian; Olvera-Molina, Sandra; Orozco-Martín, Miriam A; García-Cruz, Diana; Ríos-Flores, Izabel M; Gómez-Rodríguez, Brian Gabriel; Rivas-Soto, Gemma; Pérez-Molina, J Jesús
2018-02-19
We determined the overall prevalence of typical orofacial clefts and the potential risks for nonsyndromic cleft lip with or without cleft palate in a university hospital from West México. For the prevalence, 227 liveborn infants with typical orofacial clefts were included from a total of 81,193 births occurred during the period 2009-2016 at the "Dr. Juan I. Menchaca" Civil Hospital of Guadalajara (Guadalajara, Jalisco, Mexico). To evaluate potential risks, a case-control study was conducted among 420 newborns, including only those 105 patients with nonsyndromic cleft lip with or without cleft palate (cases), and 315 infants without birth defects (controls). Data were analyzed using multivariable logistic regression analysis expressed as adjusted odds ratio with 95% confidence intervals . The overall prevalence for typical orofacial clefts was 28 per 10,000 (95% confidence interval: 24.3-31.6), or 1 per 358 live births. The mean values for the prepregnancy weight, antepartum weight, and pre-pregnancy body mass index were statistically higher among the mothers of cases. Infants with nonsyndromic cleft lip with or without cleft palate had a significantly higher risk for previous history of any type of congenital anomaly (adjusted odds ratio: 2.7; 95% confidence interval: 1.4-5.1), history of a relative with cleft lip with or without cleft palate (adjusted odds ratio: 19.6; 95% confidence interval: 8.2-47.1), and first-trimester exposures to progestogens (adjusted odds ratio: 6.8; 95% CI 1.8-25.3), hyperthermia (adjusted odds ratio: 3.4; 95% confidence interval: 1.1-10.6), and common cold (adjusted odds ratio: 3.6; 95% confidence interval: 1.1-11.9). These risks could have contributed to explain the high prevalence of orofacial clefts in our region of Mexico, emphasizing that except for history of relatives with cleft lip with or without cleft palate, most are susceptible of modification. © 2018 Japanese Teratology Society.
Liakopoulou, Paraskevi; Liakos, Aris; Vasilakou, Despoina; Athanasiadou, Eleni; Bekiari, Eleni; Kazakos, Kyriakos; Tsapas, Apostolos
2017-06-01
Basal insulin controls primarily fasting plasma glucose but causes hypoglycaemia and weight gain, whilst glucagon like peptide 1 receptor agonists induce weight loss without increasing risk for hypoglycaemia. We conducted a systematic review and meta-analysis of randomised controlled trials to investigate the efficacy and safety of fixed ratio combinations of basal insulin with glucagon like peptide 1 receptor agonists. We searched Medline, Embase, and the Cochrane Library as well as conference abstracts up to December 2016. We assessed change in haemoglobin A 1c , body weight, and incidence of hypoglycaemia and gastrointestinal adverse events. We included eight studies with 5732 participants in the systematic review. Switch from basal insulin to fixed ratio combinations with a glucagon like peptide 1 receptor agonist was associated with 0.72% reduction in haemoglobin A 1c [95% confidence interval -1.03 to -0.41; I 2 = 93%] and 2.35 kg reduction in body weight (95% confidence interval -3.52 to -1.19; I 2 = 93%), reducing also risk for hypoglycaemia [odds ratio 0.70; 95% confidence interval 0.57 to 0.86; I 2 = 85%] but increasing incidence of nausea (odds ratio 6.89; 95% confidence interval 3.73-12.74; I 2 = 79%). Similarly, switching patients from treatment with a glucagon like peptide 1 receptor agonist to a fixed ratio combination with basal insulin was associated with 0.94% reduction in haemoglobin A 1c (95% confidence interval -1.11 to -0.77) and an increase in body weight by 2.89 kg (95% confidence interval 2.17-3.61). Fixed ratio combinations of basal insulin with glucagon like peptide 1 receptor agonists improve glycaemic control whilst balancing out risk for hypoglycaemia and gastrointestinal side effects.
Neonatal Infection in Children With Cerebral Palsy: A Registry-Based Cohort Study.
Smilga, Anne-Sophie; Garfinkle, Jarred; Ng, Pamela; Andersen, John; Buckley, David; Fehlings, Darcy; Kirton, Adam; Wood, Ellen; van Rensburg, Esias; Shevell, Michael; Oskoui, Maryam
2018-03-01
The goal of this study was to explore the association between neonatal infection and outcomes in children with cerebral palsy. We conducted a retrospective cohort study using the Canadian CP Registry. Neonatal infection was defined as meeting one of the following criteria: (1) septicemia, (2) septic shock, or (3) administration of antibiotics for ≥10 days. Phenotypic profiles of children with cerebral palsy with and without an antecedent neonatal infection were compared. Subgroup analysis was performed, stratified by gestational age (term versus preterm). Of the 1229 registry participants, 505 (41.1%) were preterm, and 192 (15.6%) met the criteria for neonatal infection with 29% of preterm children having a neonatal infection compared with 6.5% in term-born children. Children with prior neonatal infection were more likely to have a white matter injury (odds ratio 2.2, 95% confidence interval 1.5 to 3.2), spastic diplegic neurological subtype (odds ratio 1.6, 95% confidence interval 1.1 to 2.3), and sensorineural auditory impairment (odds ratio 2.1, 95% confidence interval 1.4 to 3.3). Among preterm children, neonatal infection was not associated with a difference in phenotypic profile. Term-born children with neonatal infection were more likely to have spastic triplegia or quadriplegia (odds ratio 2.4, 95% confidence interval 1.3 to 4.3), concomitant white matter and cortical injury (odds ratio 4.1, 95% confidence interval 1.6 to 10.3), and more severe gross motor ability (Gross Motor Function Classification System IV to V) (odds ratio 2.6, 95% confidence interval 1.4 to 4.8) compared with preterm children. Findings suggest a role of systemic infection on the developing brain in term-born infants, and the possibility to develop targeted therapeutic and preventive strategies to reduce cerebral palsy morbidity. Copyright © 2017. Published by Elsevier Inc.
Mackenzie, P; Pryor, D; Burmeister, E; Foote, M; Panizza, B; Burmeister, B; Porceddu, S
2014-10-01
To determine prognostic factors for locoregional relapse (LRR), distant relapse and all-cause death in a contemporary cohort of locoregionally advanced oropharyngeal squamous cell carcinoma (OSCC) treated with definitive chemoradiotherapy or radiotherapy alone. OSCC patients treated with definitive radiotherapy between 2005 and 2010 were identified from a prospective head and neck database. Patient age, gender, smoking history, human papillomavirus (HPV) status, T- and N-category, lowest involved nodal level and gross tumour volume of the primary (GTV-p) and nodal (GTV-n) disease were analysed in relation to LRR, distant relapse and death by way of univariate and multivariate analysis. In total, 130 patients were identified, 88 HPV positive, with a median follow-up of 42 months. On multivariate analysis HPV status was a significant predictor of LRR (hazard ratio 0.15; 95% confidence interval 0.05-0.51) and death (hazard ratio 0.29; 95% confidence interval 0.14-0.59) but not distant relapse (hazard ratio 0.53, 95% confidence interval 0.22-1.27). Increasing T-category was associated with a higher risk of LRR (hazard ratio 1.80 for T3/4 versus T1/2; 95% confidence interval 1.08-2.99), death (hazard ratio 1.37, 95% confidence interval 1.06-1.77) and distant relapse (hazard ratio 1.35; 95% confidence interval 1.00-1.83). Increasing GTV-p was associated with increased risk of distant relapse and death. N3 disease and low neck nodes were significant for LRR, distant relapse and death on univariate analysis only. Tumour HPV status was the strongest predictor of LRR and death. T-category is more predictive of distant relapse and may provide additional prognostic value for LRR and death when accounting for HPV status. Copyright © 2014 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Hartung, Tim J; Friedrich, Michael; Johansen, Christoffer; Wittchen, Hans-Ulrich; Faller, Herman; Koch, Uwe; Brähler, Elmar; Härter, Martin; Keller, Monika; Schulz, Holger; Wegscheider, Karl; Weis, Joachim; Mehnert, Anja
2017-11-01
Depression screening in patients with cancer is recommended by major clinical guidelines, although the evidence on individual screening tools is limited for this population. Here, the authors assess and compare the diagnostic accuracy of 2 established screening instruments: the depression modules of the 9-item Patient Health Questionnaire (PHQ-9) and the Hospital Anxiety and Depression Scale (HADS-D), in a representative sample of patients with cancer. This multicenter study was conducted with a proportional, stratified, random sample of 2141 patients with cancer across all major tumor sites and treatment settings. The PHQ-9 and HADS-D were assessed and compared in terms of diagnostic accuracy and receiver operating characteristic (ROC) curves for Diagnostic and Statistical Manual of Mental Disorders, 4th edition diagnosis of major depressive disorder using the Composite International Diagnostic Interview for Oncology as the criterion standard. The diagnostic accuracy of the PHQ-9 and HADS-D was fair for diagnosing major depressive disorder, with areas under the ROC curves of 0.78 (95% confidence interval, 0.76-0.79) and 0.75 (95% confidence interval, 0.74-0.77), respectively. The 2 questionnaires did not differ significantly in their areas under the ROC curves (P = .15). The PHQ-9 with a cutoff score ≥7 had the best screening performance, with a sensitivity of 83% (95% confidence interval, 78%-89%) and a specificity of 61% (95% confidence interval, 59%-63%). The American Society of Clinical Oncology guideline screening algorithm had a sensitivity of 44% (95% confidence interval, 36%-51%) and a specificity of 84% (95% confidence interval, 83%-85%). In patients with cancer, the screening performance of both the PHQ-9 and the HADS-D was limited compared with a standardized diagnostic interview. Costs and benefits of routinely screening all patients with cancer should be weighed carefully. Cancer 2017;123:4236-4243. © 2017 American Cancer Society. © 2017 American Cancer Society.
Mocroft, Amanda; Sterne, Jonathan A C; Egger, Matthias; May, Margaret; Grabar, Sophie; Furrer, Hansjakob; Sabin, Caroline; Fatkenheuer, Gerd; Justice, Amy; Reiss, Peter; d'Arminio Monforte, Antonella; Gill, John; Hogg, Robert; Bonnet, Fabrice; Kitahata, Mari; Staszewski, Schlomo; Casabona, Jordi; Harris, Ross; Saag, Michael
2009-04-15
The extent to which mortality differs following individual acquired immunodeficiency syndrome (AIDS)-defining events (ADEs) has not been assessed among patients initiating combination antiretroviral therapy. We analyzed data from 31,620 patients with no prior ADEs who started combination antiretroviral therapy. Cox proportional hazards models were used to estimate mortality hazard ratios for each ADE that occurred in >50 patients, after stratification by cohort and adjustment for sex, HIV transmission group, number of antiretroviral drugs initiated, regimen, age, date of starting combination antiretroviral therapy, and CD4+ cell count and HIV RNA load at initiation of combination antiretroviral therapy. ADEs that occurred in <50 patients were grouped together to form a "rare ADEs" category. During a median follow-up period of 43 months (interquartile range, 19-70 months), 2880 ADEs were diagnosed in 2262 patients; 1146 patients died. The most common ADEs were esophageal candidiasis (in 360 patients), Pneumocystis jiroveci pneumonia (320 patients), and Kaposi sarcoma (308 patients). The greatest mortality hazard ratio was associated with non-Hodgkin's lymphoma (hazard ratio, 17.59; 95% confidence interval, 13.84-22.35) and progressive multifocal leukoencephalopathy (hazard ratio, 10.0; 95% confidence interval, 6.70-14.92). Three groups of ADEs were identified on the basis of the ranked hazard ratios with bootstrapped confidence intervals: severe (non-Hodgkin's lymphoma and progressive multifocal leukoencephalopathy [hazard ratio, 7.26; 95% confidence interval, 5.55-9.48]), moderate (cryptococcosis, cerebral toxoplasmosis, AIDS dementia complex, disseminated Mycobacterium avium complex, and rare ADEs [hazard ratio, 2.35; 95% confidence interval, 1.76-3.13]), and mild (all other ADEs [hazard ratio, 1.47; 95% confidence interval, 1.08-2.00]). In the combination antiretroviral therapy era, mortality rates subsequent to an ADE depend on the specific diagnosis. The proposed classification of ADEs may be useful in clinical end point trials, prognostic studies, and patient management.
Nelson, Winnie W; Wang, Li; Baser, Onur; Damaraju, Chandrasekharrao V; Schein, Jeffrey R
2015-02-01
Although efficacious in stroke prevention in non-valvular atrial fibrillation, many warfarin patients are sub-optimally managed. To evaluate the association of international normalized ratio control and clinical outcomes among new warfarin patients with non-valvular atrial fibrillation. Adult non-valvular atrial fibrillation patients (≥18 years) initiating warfarin treatment were selected from the US Veterans Health Administration dataset between 10/2007 and 9/2012. Valid international normalized ratio values were examined from the warfarin initiation date through the earlier of the first clinical outcome, end of warfarin exposure or death. Each patient contributed multiple in-range and out-of-range time periods. The relative risk ratios of clinical outcomes associated with international normalized ratio control were estimated. 34,346 patients were included for analysis. During the warfarin exposure period, the incidence of events per 100 person-years was highest when patients had international normalized ratio <2:13.66 for acute coronary syndrome; 10.30 for ischemic stroke; 2.93 for transient ischemic attack; 1.81 for systemic embolism; and 4.55 for major bleeding. Poisson regression confirmed that during periods with international normalized ratio <2, patients were at increased risk of developing acute coronary syndrome (relative risk ratio: 7.9; 95 % confidence interval 6.9-9.1), ischemic stroke (relative risk ratio: 7.6; 95 % confidence interval 6.5-8.9), transient ischemic attack (relative risk ratio: 8.2; 95 % confidence interval 6.1-11.2), systemic embolism (relative risk ratio: 6.3; 95 % confidence interval 4.4-8.9) and major bleeding (relative risk ratio: 2.6; 95 % confidence interval 2.2-3.0). During time periods with international normalized ratio >3, patients had significantly increased risk of major bleeding (relative risk ratio: 1.5; 95 % confidence interval 1.2-2.0). In a Veterans Health Administration non-valvular atrial fibrillation population, exposure to out-of-range international normalized ratio values was associated with significantly increased risk of adverse clinical outcomes.
The prevalence of diagnosed tourette syndrome in Canada: A national population-based study.
Yang, Jaeun; Hirsch, Lauren; Martino, Davide; Jette, Nathalie; Roberts, Jodie; Pringsheim, Tamara
2016-11-01
The objective of this study was to examine: (1) the prevalence of diagnosed Tourette syndrome in Canada by sex in youth (aged 12-17) and adults and (2) socioeconomic factors in this population. The majority of epidemiological studies of tics have focused on children and youth, with few studies describing the prevalence of tics in adult populations. Canadian data on Tourette syndrome prevalence were derived from the Canadian Community Health Survey 2010 and 2011 cycles, a Statistics Canada population-based cross-sectional survey that collects information related to health status. We determined the prevalence of diagnosed Tourette syndrome and examined sociodemographic factors, including age, sex, education, income, employment, and birthplace. Overall, 122,884 Canadians participated in the surveys, with 122 participants diagnosed with Tourette syndrome. The prevalence of Tourette syndrome was higher in males in youth: 6.03 per 1000 (95% confidence interval: 3.24-8.81) in males versus 0.48 per 1,000 (95% confidence interval: 0.05-0.91) in females, with a prevalence risk ratio of 5.31 (95% confidence interval: 2.38-11.81). In adults, the prevalence of Tourette syndrome was 0.89 per 1,000 (95% confidence interval: 0.48-1.29) in males versus 0.44 (95% confidence interval: 0.16.0-0.71) in females, with a prevalence risk ratio of 1.93 (95% confidence interval: 1.21-3.08). After adjusting for age and sex, adults with Tourette syndrome had lower odds of receiving postsecondary education or being employed and higher odds of having income lower than the median and receiving governmental support. Data on the prevalence of Tourette syndrome in adults are scarce because most studies focus on children. Our data demonstrate a decreasing prevalence risk ratio for sex in adults compared to children. A diagnosis of Tourette syndrome is associated with lower education, income, and employment in adulthood. © 2016 International Parkinson and Movement Disorder Society. © 2016 International Parkinson and Movement Disorder Society.
Suicide in patients with gastric cancer: a population-based study.
Sugawara, Akitomo; Kunieda, Etsuo
2016-09-01
We conducted this study to examine the rate of suicide in patients with gastric cancer and to identify factors associated with increased risk of suicide using the Surveillance, Epidemiology, and End Results database. The database was queried for patients who were diagnosed with gastric cancer from 1998 to 2011. The rate of suicide and standardized mortality ratio were calculated. Multivariable analyses were conducted to identify factors associated with increased risk of suicide. A total of 65 535 patients with 109 597 person-years of follow-up were included. A total of 68 patients died of suicide. The age-adjusted rate of suicide was 34.6 per 100 000 person-years (standardized mortality ratios, 4.07; 95% confidence interval, 3.18-5.13). The rate of suicide was highest within the first 3 months after cancer diagnosis (standardized mortality ratios, 67.67; 95% confidence interval, 40.74-106.15). Results of multivariable analyses showed that male sex (incidence rate ratio, 7.15; 95% confidence interval, 3.05-16.78; P < 0.0001), White race (incidence rate ratio, 3.23; 95% confidence interval, 1.00-10.35; P = 0.0491), unmarried status (incidence rate ratio, 2.01; 95% confidence interval, 1.22-3.30; P = 0.0060) and distant stage disease (incidence rate ratio, 2.90; 95% confidence interval, 1.72-4.92; P < 0.0001) were significantly associated with increased risk of suicide. Patients with gastric cancer have an ~4-fold higher risk of suicide compared with the general US population. The suicide risk is highest within the first 3 months after diagnosis. Male sex, White race, unmarried status and distant stage disease are significantly associated with increased risk of suicide. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Tan, Woan Shin; Lee, Angel; Yang, Sze Yee; Chan, Susan; Wu, Huei Yaw; Ng, Charis Wei Ling; Heng, Bee Hoon
2016-07-01
Terminally ill patients at the end-of-life do transit between care settings due to their complex care needs. Problems of care fragmentation could result in poor quality of care. We aimed to evaluate the impact of an integrated hospice home care programme on acute care service usage and on the share of home deaths. The retrospective study cohort comprised patients who were diagnosed with cancer, had an expected prognosis of 1 year or less, and were referred to a home hospice. The intervention group comprised deceased patients enrolled in the integrated hospice home care programme between September 2012 and June 2014. The historical comparison group comprised deceased patients who were referred to other home hospices between January 2007 and January 2011. There were 321 cases and 593 comparator subjects. Relative to the comparator group, the share of hospital deaths was significantly lower for programme participants (12.1% versus 42.7%). After adjusting for differences at baseline, the intervention group had statistically significantly lower emergency department visits at 30 days (incidence rate ratio: 0.38; 95% confidence interval: 0.31-0.47), 60 days (incidence rate ratio: 0.61; 95% confidence interval: 0.54-0.69) and 90 days (incidence rate ratio: 0.69; 95% confidence interval: 0.62-0.77) prior to death. Similar results held for the number of hospitalisations at 30 days (incidence rate ratio: 0.48; 95% confidence interval: 0.40-0.58), 60 days (incidence rate ratio: 0.71; 95% confidence interval: 0.62-0.82) and 90 days (incidence rate ratio: 0.77; 95% confidence interval: 0.68-0.88) prior to death. Our results demonstrated that by integrating services between acute care and home hospice care, a reduction in acute care service usage could occur. © The Author(s) 2016.
Prevalence of dry eye syndrome in an adult population.
Hashemi, Hassan; Khabazkhoob, Mehdi; Kheirkhah, Ahmad; Emamian, Mohammad Hassan; Mehravaran, Shiva; Shariati, Mohammad; Fotouhi, Akbar
2014-04-01
To determine the prevalence of dry eye syndrome in the general 40- to 64-year-old population of Shahroud, Iran. Population-based cross-sectional study. Through cluster sampling, 6311 people were selected and 5190 participated. Assessment of dry eye was done in a random subsample of 1008 people. Subjective assessment for dry eye syndrome was performed using Ocular Surface Disease Index questionnaire. In addition, the following objective tests of dry eye syndrome were employed: Schirmer test, tear break-up time, and fluorescein and Rose Bengal staining using the Oxford grading scheme. Those with an Ocular Surface Disease Index score ≥23 were considered symptomatic, and dry eye syndrome was defined as having symptoms and at least one positive objective sign. The prevalence of dry eye syndrome was 8.7% (95% confidence interval 6.9-10.6). Assessment of signs showed an abnormal Schirmer score in 17.8% (95% confidence interval 15.5-20.0), tear break-up time in 34.2% (95% confidence interval 29.5-38.8), corneal fluorescein staining (≥1) in 11.3% (95% confidence interval 8.5-14.1) and Rose Bengal staining (≥3 for cornea and/or conjunctiva) in 4.9% (95% confidence interval 3.4-6.5). According to the Ocular Surface Disease Index scores, 18.3% (95% confidence interval 15.9-20.6) had dry eye syndrome symptoms. The prevalence of dry eye syndrome was significantly higher in women (P = 0.010) and not significantly associated with age (P = 0.291). The objective dry eye syndrome signs significantly increased with age. Based on the findings, the prevalence of dry eye syndrome in the studied population is in the mid-range. The prevalence is higher in women. Also, objective tests tend to turn abnormal at higher age. Pterygium is associated with dry eye syndrome and increased its symptoms. © 2013 Royal Australian and New Zealand College of Ophthalmologists.
The diagnostic value of narrow-band imaging for early and invasive lung cancer: a meta-analysis.
Zhu, Juanjuan; Li, Wei; Zhou, Jihong; Chen, Yuqing; Zhao, Chenling; Zhang, Ting; Peng, Wenjia; Wang, Xiaojing
2017-07-01
This study aimed to compare the ability of narrow-band imaging to detect early and invasive lung cancer with that of conventional pathological analysis and white-light bronchoscopy. We searched the PubMed, EMBASE, Sinomed, and China National Knowledge Infrastructure databases for relevant studies. Meta-disc software was used to perform data analysis, meta-regression analysis, sensitivity analysis, and heterogeneity testing, and STATA software was used to determine if publication bias was present, as well as to calculate the relative risks for the sensitivity and specificity of narrow-band imaging vs those of white-light bronchoscopy for the detection of early and invasive lung cancer. A random-effects model was used to assess the diagnostic efficacy of the above modalities in cases in which a high degree of between-study heterogeneity was noted with respect to their diagnostic efficacies. The database search identified six studies including 578 patients. The pooled sensitivity and specificity of narrow-band imaging were 86% (95% confidence interval: 83-88%) and 81% (95% confidence interval: 77-84%), respectively, and the pooled sensitivity and specificity of white-light bronchoscopy were 70% (95% confidence interval: 66-74%) and 66% (95% confidence interval: 62-70%), respectively. The pooled relative risks for the sensitivity and specificity of narrow-band imaging vs the sensitivity and specificity of white-light bronchoscopy for the detection of early and invasive lung cancer were 1.33 (95% confidence interval: 1.07-1.67) and 1.09 (95% confidence interval: 0.84-1.42), respectively, and sensitivity analysis showed that narrow-band imaging exhibited good diagnostic efficacy with respect to detecting early and invasive lung cancer and that the results of the study were stable. Narrow-band imaging was superior to white light bronchoscopy with respect to detecting early and invasive lung cancer; however, the specificities of the two modalities did not differ significantly.
Ahlin, Kristina; Jacobsson, Bo; Nilsson, Staffan; Himmelmann, Kate
2017-07-01
Antecedents of accompanying impairments in cerebral palsy and their relation to neuroimaging patterns need to be explored. A population-based study of 309 children with cerebral palsy born at term between 1983 and 1994. Prepartum, intrapartum, and postpartum variables previously studied as antecedents of cerebral palsy type and motor severity were analyzed in children with cerebral palsy and cognitive impairment and/or epilepsy, and in children with cerebral palsy without these accompanying impairments. Neuroimaging patterns and their relation to identified antecedents were analyzed. Data were retrieved from the cerebral palsy register of western Sweden, and from obstetric and neonatal records. Children with cerebral palsy and accompanying impairments more often had low birthweight (kg) (odds ratio 0.5, 95% confidence interval 0.3-0.8), brain maldevelopment known at birth (p = 0.007, odds ratio ∞) and neonatal infection (odds ratio 5.4, 95% confidence interval 1.04-28.4). Moreover, neuroimaging patterns of maldevelopment (odds ratio 7.2, 95% confidence interval 2.9-17.2), cortical/subcortical lesions (odds ratio 5.3, 95% confidence interval 2.3-12.2) and basal ganglia lesions (odds ratio 7.6, 95% confidence interval 1.4-41.3) were more common, wheras white matter injury was found significantly less often (odds ratio 0.2, 95% confidence interval 0.1-0.5). In most children with maldevelopment, the intrapartum and postpartum periods were uneventful (p < 0.05). Cerebral maldevelopment was associated with prepartum antecedents, whereas subcortical/cortical and basal ganglia lesions were associated with intrapartum and postpartum antecedents. No additional factor other than those related to motor impairment was associated with epilepsy and cognitive impairment in cerebral palsy. Timing of antecedents deemed important for the development of cerebral palsy with accompanying impairments were supported by neuroimaging patterns. © 2017 Nordic Federation of Societies of Obstetrics and Gynecology.
Breast cancer biology varies by method of detection and may contribute to overdiagnosis.
Hayse, Brandon; Hooley, Regina J; Killelea, Brigid K; Horowitz, Nina R; Chagpar, Anees B; Lannin, Donald R
2016-08-01
Recently, it has been suggested that screening mammography may result in some degree of overdiagnosis (ie, detection of breast cancers that would never become clinically important within the lifespan of the patient). The extent and biology of these overdiagnosed cancers, however, is not well understood, and the effect of newer screening modalities on overdiagnosis is unknown. We performed a retrospective review of a prospectively collected database of breast cancers diagnosed at the Yale Breast Center from 2004-2014. The mode of initial presentation was categorized into 5 groups: screening mammogram, screening magnetic resonance imaging, screening ultrasonography, self-detected masses, and physician-detected masses. Compared with cancers presenting with masses, cancers detected by image-based screening were more likely to present with ductal carcinoma-in-situ or T1 cancers (P < .001). In addition to a simple stage shift, however, cancers detected by image-based screening were also more likely to be luminal and low-grade cancers; symptomatic cancers were more likely high-grade and triple-negative (P < .001, respectively). On a multivariate analysis, adjusting for age, race, and tumor size, cancers detected by mammogram, US, and magnetic resonance imaging had greater odds of being luminal (odds ratio 1.8, 95% confidence interval, 1.5-2.3; odds ratio 2.2, 95% confidence interval, 1.1-4.7; and odds ratio 4.7, 95% confidence interval, 2.1-10.6, respectively), and low-grade (odds ratio 2.2, 95% confidence interval, 1.6-2.9; odds ratio 4.9, 95% confidence interval, 2.7-8.9; and odds ratio 4.6, 95% confidence interval, 2.6-8.1, respectively) compared with cancers presenting with self-detected masses. Screening detects cancers with more indolent biology, potentially contributing to the observed rate of overdiagnosis. With magnetic resonance imaging and US being used more commonly for screening, the rate of overdiagnosis may increase further. Copyright © 2016. Published by Elsevier Inc.
Alvarado-Esquivel, Cosme; Rico-Almochantaf, Yazmin Del Rosario; Hernández-Tinoco, Jesús; Quiñones-Canales, Gerardo; Sánchez-Anguiano, Luis Francisco; Torres-González, Jorge; Ramírez-Valles, Eda Guadalupe; Minjarez-Veloz, Andrea
2018-01-01
This study aimed to determine the association between infection with Toxoplasma gondii and epilepsy in patients attended to in a public hospital in the northern Mexican city of Durango. We performed an age- and gender-matched case-control study of 99 patients suffering from epilepsy and 99 without epilepsy. Sera of participants were analyzed for anti- T. gondii IgG and IgM antibodies using commercially available enzyme-linked immunoassays. Seropositive samples to T. gondii were further analyzed for detection of T. gondii DNA by polymerase chain reaction. Anti- T. gondii IgG antibodies were found in 10 (10.1%) of the 99 cases and in 6 (6.1%) of the 99 controls (odds ratio = 1.74; 95% confidence interval: 0.60-4.99; p = 0.43). High (> 150 IU/mL) levels of anti- T. gondii IgG antibodies were found in 6 of the 99 cases and in 4 of the 99 controls (odds ratio = 1.53; 95% confidence interval: 0.41-5.60; p = 0.74). Anti- T. gondii IgM antibodies were found in 2 of the 10 IgG seropositive cases, and in 2 of the 6 IgG seropositive controls (odds ratio = 0.50; 95% confidence interval: 0.05-4.97; p = 0.60). T. gondii DNA was not found in any of the 10 anti- T. gondii IgG positive patients. Bivariate analysis of IgG seropositivity to T. gondii and International Statistical Classification of Diseases and related Health Problems, 10th Edition codes of epilepsy showed an association between seropositivity and G40.1 code (odds ratio = 22.0; 95% confidence interval: 2.59-186.5; p = 0.008). Logistic regression analysis showed an association between T. gondii infection and consumption of goat meat (odds ratio = 6.5; 95% confidence interval: 1.22-34.64; p = 0.02), unwashed raw vegetables (odds ratio = 26.3; 95% confidence interval: 2.61-265.23; p = 0.006), and tobacco use (odds ratio = 6.2; 95% confidence interval: 1.06-36.66; p = 0.04). Results suggest that T. gondii infection does not increase the risk of epilepsy in our setting; however, infection might be linked to specific types of epilepsy. Factors associated with T. gondii infection found in this study may aid in the design of preventive measures against toxoplasmosis.
Agarwal, Silky; Changotra, Harish
2017-01-01
Protein tyrosine phosphatase, non-receptor type 22 gene, which translates to lymphoid tyrosine phosphatase, is considered to be a susceptibility gene marker associated with several autoimmune diseases. Several studies have demonstrated the association of protein tyrosine phosphatase, non-receptor type 22 +1858C→T polymorphism with vitiligo. However, these studies showed conflicting results. Meta-analysis of the same was conducted earlier that included fewer number of publications in their study. We performed a meta-analysis of a total of seven studies consisting of 2094 cases and 3613 controls to evaluate the possible association of protein tyrosine phosphatase, non-receptor type 22 +1858C>T polymorphism with vitiligo susceptibility. We conducted a literature search in PubMed, Google Scholar and Dogpile for all published paper on protein tyrosine phosphatase, non-receptor type 22 +1858C→T polymorphism and vitiligo risk till June 2016. Data analysis was performed by RevMan 5.3 and comprehensive meta-analysis v3.0 software. Meta-analysis showed an overall significant association of protein tyrosine phosphatase, non- receptor type 22 +1858C→T polymorphism with vitiligo in all models (allelic model [T vs. C]: odds ratio = 1.50, 95% confidence interval [1.32-1.71], P< 0.001; dominant model [TT + CT vs. CC]: odds ratio = 1.61, 95% confidence interval [1.16-2.24], P = 0.004; recessive model [TT vs. CT + CC]: odds ratio = 4.82, 95% confidence interval [1.11-20.92], P = 0.04; homozygous model [TT vs. CC]: odds ratio = 5.34, 95% confidence interval [1.23-23.24], P = 0.03; co-dominant model [CT vs. CC]: odds ratio = 1.52, 95% confidence interval [1.09-2.13], P = 0.01). No publication bias was detected in the funnel plot study. Limited ethnic-based studies, unable to satisfy data by gender or vitiligo-type are some limitations of the present meta-analysis. Stratifying data by ethnicity showed an association of protein tyrosine phosphatase, non-receptor type 22 +1858C→T with vitiligo in European population (odds ratio = 1.53, 95% confidence interval [1.34-1.75], P< 0.001) but not in Asian population (odds ratio = 0.59, 95% confidence interval [0.26-1.32], P = 0.2). In conclusion, protein tyrosine phosphatase, non-receptor type 22 +1858 T allele predisposes European individuals to vitiligo.
Teacher and peer reports of overweight and bullying among young primary school children.
Jansen, Pauline W; Verlinden, Marina; Dommisse-van Berkel, Anke; Mieloo, Cathelijne L; Raat, Hein; Hofman, Albert; Jaddoe, Vincent W V; Verhulst, Frank C; Jansen, Wilma; Tiemeier, Henning
2014-09-01
Overweight is a potential risk factor for peer victimization in late childhood and adolescence. The current study investigated the association between BMI in early primary school and different bullying involvement roles (uninvolved, bully, victim, and bully-victim) as reported by teachers and children themselves. In a population-based study in the Netherlands, measured BMI and teacher-reported bullying behavior were available for 4364 children (mean age = 6.2 years). In a subsample of 1327 children, a peer nomination method was used to obtain child reports of bullying. In both teacher- and child-reported data, a higher BMI was associated with more victimization and more bullying perpetration. For instance, a 1-point increase in BMI was associated with a 0.05 increase on the standardized teacher-reported victimization score (95% confidence interval, 0.03 to 0.07; P < .001). Combining the victimization and bullying scores into different types of bullying involvement showed that children with obesity, but not children with overweight, had a significantly higher risk to be a bully-victim (odds ratio = 2.25; 95% confidence interval, 1.62 to 3.14) than normal-weight peers. At school entry, a high BMI is a risk factor associated with victimization and bullying perpetration, with obese children particularly likely to be victims and aggressors. Results were consistent for teacher and child reports of bullying, supporting the validity of our findings. Possibly, obesity triggers peer problems, but the association may also reflect a common underlying cause that makes obese children vulnerable to bullying involvement. Copyright © 2014 by the American Academy of Pediatrics.
Holdenrieder, Stefan; Molina, Rafael; Qiu, Ling; Zhi, Xiuyi; Rutz, Sandra; Engel, Christine; Kasper-Sauer, Pia; Dayyani, Farshid; Korse, Catharina M
2018-04-01
In squamous cell carcinoma, squamous cell carcinoma antigen levels are often elevated. This multi-center study evaluated the technical performance of a new Elecsys ® squamous cell carcinoma assay, which measures serum squamous cell carcinoma antigen 1 and 2 levels in an equimolar manner, and investigated the potential of squamous cell carcinoma antigen for differential diagnosis of cervical, lung, and head and neck squamous cell carcinoma.Assay precision and method comparison experiments were performed across three European sites. Reference ranges for reportedly healthy individuals were determined using samples from banked European and Chinese populations. Differential diagnosis experiments determined whether cervical, lung, or head and neck cancer could be differentiated from apparently healthy, benign, or other malignant cohorts using squamous cell carcinoma antigen levels alone. Squamous cell carcinoma antigen cut-off levels were calculated based on squamous cell carcinoma antigen levels at 95% specificity. Repeatability coefficients of variation across nine analyte concentrations were ≤5.3%, and intermediate precision coefficients of variation were ≤10.3%. Method comparisons showed good correlations with Architect and Kryptor systems (slopes of 1.1 and 1.5, respectively). Reference ranges for 95th percentiles for apparently healthy individuals were 2.3 ng/mL (95% confidence interval: 1.9-3.8; European cohort, n = 153) and 2.7 ng/mL (95% confidence interval: 2.2-3.3; Chinese cohort, n = 146). Strongest differential diagnosis results were observed for cervical squamous cell carcinoma: receiver operating characteristic analysis showed that squamous cell carcinoma antigen levels (2.9 ng/mL cut-off) differentiate cervical squamous cell carcinoma (n = 127) from apparently healthy females (n = 286; area under the curve: 86.2%; 95% confidence interval: 81.8-90.6; sensitivity: 61.4%; specificity: 95.6%), benign diseases (n = 187; area under the curve: 86.3%; 95% confidence interval: 81.2-91.3; sensitivity: 61.4%; specificity: 95.0%), and other cervical cancers (n = 157; area under the curve: 78.9%; 95% confidence interval: 70.8-87.1; sensitivity: 61.4%; specificity: 86.7%). Squamous cell carcinoma may also aid in the differential diagnosis of lung cancer. The Elecsys squamous cell carcinoma assay exhibited good technical performance and is suitable for differential diagnosis of cervical squamous cell carcinoma in clinical practice.
Pihlajamäki, Harri; Hietaniemi, Kalevi; Paavola, Mika; Visuri, Tuomo; Mattila, Ville M
2010-10-20
Some have recommended surgical treatment of Grade-III lateral ligament injuries in very active individuals with high functional demands on the ankle. The purpose of this study was to establish whether surgery provides better long-term results than functional treatment for acute ruptures of the lateral ligaments of the ankle. Physically active Finnish men (mean age, 20.4 years) with an acute Grade-III lateral ligament rupture of the ankle were randomly allocated to surgical (n = 25) or functional (n = 26) treatment. Ligament injury was confirmed with stress radiographs. Surgical treatment comprised suture repair of the injured ligament(s) within the first week after injury. A below-the-knee plaster cast was worn for six weeks with full weight-bearing. Functional treatment consisted of the use of an Aircast ankle brace for three weeks. The main outcome measures included final follow-up examinations, calculation of an ankle score, stress radiographs, and magnetic resonance imaging scans. Fifteen (60%) of twenty-five surgically treated patients and eighteen (69%) of twenty-six functionally treated patients returned for long-term follow-up (mean duration, fourteen years). All patients in both groups had recovered their preinjury activity level and reported that they could walk and run normally. The prevalence of reinjury was one of fifteen in the surgical group and seven of eighteen in the functional treatment group (risk difference: 32%; 95% confidence interval: 6% to 58%). The mean ankle score did not differ significantly between the groups (mean difference: 8.3 points; 95% confidence interval: -0.03 to 16.6 points). Stress radiographs revealed no difference between groups with regard to the mean anterior drawer (-1 mm in the surgical group and 0 mm in the functional treatment group; mean difference: 0.7 mm; 95% confidence interval: -1.4 to 2.7 mm) or mean tilt angle (0° in both groups; mean difference: 0.1°; 95% confidence interval: -3.2° to 3.5°). Grade-II osteoarthritis was observed on magnetic resonance images of four of the fifteen surgically treated patients and in none of the eighteen functionally treated patients (risk difference: 27%; 95% confidence interval: 4% to 49%). These findings indicate that, in terms of recovery of the preinjury activity level, the long-term results of surgical treatment of acute lateral ligament rupture of the ankle correspond with those of functional treatment. Although surgery appeared to decrease the prevalence of reinjury of the lateral ligaments, there may be an increased risk for the subsequent development of osteoarthritis.
Alhazzani, Waleed; Alenezi, Farhan; Jaeschke, Roman Z; Moayyedi, Paul; Cook, Deborah J
2013-03-01
Critically ill patients may develop bleeding caused by stress ulceration. Acid suppression is commonly prescribed for patients at risk of stress ulcer bleeding. Whether proton pump inhibitors are more effective than histamine 2 receptor antagonists is unclear. To determine the efficacy and safety of proton pump inhibitors vs. histamine 2 receptor antagonists for the prevention of upper gastrointestinal bleeding in the ICU. We searched Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, ACPJC, CINHAL, online trials registries (clinicaltrials.gov, ISRCTN Register, WHO ICTRP), conference proceedings databases, and reference lists of relevant articles. Randomized controlled parallel group trials comparing proton pump inhibitors to histamine 2 receptor antagonists for the prevention of upper gastrointestinal bleeding in critically ill patients, published before March 2012. Two reviewers independently applied eligibility criteria, assessed quality, and extracted data. The primary outcomes were clinically important upper gastrointestinal bleeding and overt upper gastrointestinal bleeding; secondary outcomes were nosocomial pneumonia, ICU mortality, ICU length of stay, and Clostridium difficile infection. Trial authors were contacted for additional or clarifying information. Fourteen trials enrolling a total of 1,720 patients were included. Proton pump inhibitors were more effective than histamine 2 receptor antagonists at reducing clinically important upper gastrointestinal bleeding (relative risk 0.36; 95% confidence interval 0.19-0.68; p = 0.002; I = 0%) and overt upper gastrointestinal bleeding (relative risk 0.35; 95% confidence interval 0.21-0.59; p < 0.0001; I = 15%). There were no differences between proton pump inhibitors and histamine 2 receptor antagonists in the risk of nosocomial pneumonia (relative risk 1.06; 95% confidence interval 0.73-1.52; p = 0.76; I = 0%), ICU mortality (relative risk 1.01; 95% confidence interval 0.83-1.24; p = 0.91; I = 0%), or ICU length of stay (mean difference -0.54 days; 95% confidence interval -2.20 to 1.13; p = 0.53; I = 39%). No trials reported on C. difficile infection. In critically ill patients, proton pump inhibitors seem to be more effective than histamine 2 receptor antagonists in preventing clinically important and overt upper gastrointestinal bleeding. The robustness of this conclusion is limited by the trial methodology, differences between lower and higher quality trials, sparse data, and possible publication bias. We observed no differences between drugs in the risk of pneumonia, death, or ICU length of stay.
Deferasirox for managing transfusional iron overload in people with sickle cell disease.
Meerpohl, Joerg J; Schell, Lisa K; Rücker, Gerta; Motschall, Edith; Fleeman, Nigel; Niemeyer, Charlotte M; Bassler, Dirk
2014-05-27
Sickle cell disease (SCD) is a group of genetic haemoglobin disorders, that occurs in about 2.2 per 1000 births worldwide. Increasingly, some people with SCD develop secondary iron overload due to occasional red blood cell transfusions or are on long-term transfusion programmes for e.g. secondary stroke prevention. Iron chelation therapy can prevent long-term complications.Deferoxamine and deferiprone have been found to be efficacious. However, questions exist about the effectiveness and safety of the newer oral chelator deferasirox. To assess the effectiveness and safety of oral deferasirox in people with SCD and secondary iron overload. We searched the Cystic Fibrosis & Genetic Disorders Group's Haemoglobinopathies Trials Register: date of most recent search:13 March 2014.We searched MEDLINE, Embase, Biosis Previews, Web of Science, Derwent Drug File, XTOXLINE, EBMR and The Cochrane Library, respectively; date of most recent searches: 02 August 2013.We searched four trial registries: www.controlled-trials.com; www.clinicaltrials.gov; www.who.int./ictrp/en/; www.drks.de; date of most recent searches: 03 June 2013. Randomised controlled trials comparing deferasirox with no therapy or placebo or with another iron chelating treatment schedule. Two authors independently assessed risk of bias and extracted data. We contacted the corresponding study authors for additional information. Two studies (with 203 and 212 people) comparing the efficacy and safety of deferasirox and deferoxamine after 12 months and 24 weeks, respectively, were included. The overall quality, according to GRADE, for the main outcomes was moderate to low. Only limited data were available on mortality and end-organ damage, although one study did assess mortality, relative risk 1.26 (95% confidence interval 0.05 to 30.41), the 24-week follow up was too short to allow us to draw firm conclusions. One study reported a relative risk of 1.26 for the incidence of type 2 diabetes mellitus (95% confidence interval 0.05 to 30.41). Serum ferritin reduction was significantly greater with deferoxamine, mean difference of change of 440.69 µg/l (95% confidence interval 11.73 to 869.64). Liver iron concentration (reported in one study) measured by superconduction quantum interference device showed no significant difference for the overall group of patients adjusted for transfusion category, mean difference -0.20 mg Fe/g dry weight (95% confidence interval -3.15 to 2.75).The occurrence of serious adverse events did not differ between drugs. Nausea, diarrhoea and rash occurred significantly more often in people treated with deferasirox, while adverse events of any kind were more often reported for patients treated with deferoxamine (one study). The mean increase of creatinine was also significantly higher with deferasirox, mean difference 3.24 (95% confidence interval 0.45 to 6.03). Long-term adverse events could not be measured in the included studies (follow up 52 weeks and 24 weeks). Patient satisfaction and the likelihood of continuing treatment, were significantly better with deferasirox. Deferasirox appears to be of similar efficacy to deferoxamine depending on depending on the appropriate ratio of doses of deferoxamine and deferasirox being compared. However, only limited evidence is available assessing the efficacy regarding patient-important outcomes. The short-term safety of deferasirox seems to be acceptable, however, follow up in the available studies was too short to assess long-term side effects. Long-term safety and efficacy data are available from a non-controlled extension phase not included in our review; however, no valid comparative conclusions can be drawn and future studies should assess comparatively long-term outcomes both for safety and efficacy.
Howden-Chapman, Philippa; Pierse, Nevil; Nicholls, Sarah; Gillespie-Bennett, Julie; Viggers, Helen; Cunningham, Malcolm; Phipps, Robyn; Boulic, Mikael; Fjällström, Pär; Free, Sarah; Chapman, Ralph; Lloyd, Bob; Wickens, Kristin; Shields, David; Baker, Michael; Cunningham, Chris; Woodward, Alistair; Bullen, Chris; Crane, Julian
2008-09-23
To assess whether non-polluting, more effective home heating (heat pump, wood pellet burner, flued gas) has a positive effect on the health of children with asthma. Randomised controlled trial. Households in five communities in New Zealand. 409 children aged 6-12 years with doctor diagnosed asthma. Installation of a non-polluting, more effective home heater before winter. The control group received a replacement heater at the end of the trial. The primary outcome was change in lung function (peak expiratory flow rate and forced expiratory volume in one second, FEV(1)). Secondary outcomes were child reported respiratory tract symptoms and daily use of preventer and reliever drugs. At the end of winter 2005 (baseline) and winter 2006 (follow-up) parents reported their child's general health, use of health services, overall respiratory health, and housing conditions. Nitrogen dioxide levels were measured monthly for four months and temperatures in the living room and child's bedroom were recorded hourly. Improvements in lung function were not significant (difference in mean FEV(1) 130.7 ml, 95% confidence interval -20.3 to 281.7). Compared with children in the control group, however, children in the intervention group had 1.80 fewer days off school (95% confidence interval 0.11 to 3.13), 0.40 fewer visits to a doctor for asthma (0.11 to 0.62), and 0.25 fewer visits to a pharmacist for asthma (0.09 to 0.32). Children in the intervention group also had fewer reports of poor health (adjusted odds ratio 0.48, 95% confidence interval 0.31 to 0.74), less sleep disturbed by wheezing (0.55, 0.35 to 0.85), less dry cough at night (0.52, 0.32 to 0.83), and reduced scores for lower respiratory tract symptoms (0.77, 0.73 to 0.81) than children in the control group. The intervention was associated with a mean temperature rise in the living room of 1.10 degrees C (95% confidence interval 0.54 degrees C to 1.64 degrees C) and in the child's bedroom of 0.57 degrees C (0.05 degrees C to 1.08 degrees C). Lower levels of nitrogen dioxide were measured in the living rooms of the intervention households than in those of the control households (geometric mean 8.5 microg/m(3) v 15.7 microg/m(3), P<0.001). A similar effect was found in the children's bedrooms (7.3 microg/m(3) v 10.9 microg/m(3), P<0.001). Installing non-polluting, more effective heating in the homes of children with asthma did not significantly improve lung function but did significantly reduce symptoms of asthma, days off school, healthcare utilisation, and visits to a pharmacist. Clinical Trials NCT00489762.
Characterization of Myocardial Repolarization Reserve in Adolescent Females With Anorexia Nervosa.
Padfield, Gareth J; Escudero, Carolina A; DeSouza, Astrid M; Steinberg, Christian; Gibbs, Karen; Puyat, Joseph H; Lam, Pei Yoong; Sanatani, Shubhayan; Sherwin, Elizabeth; Potts, James E; Sandor, George; Krahn, Andrew D
2016-02-09
Patients with anorexia nervosa exhibit abnormal myocardial repolarization and are susceptible to sudden cardiac death. Exercise testing is useful in unmasking QT prolongation in disorders associated with abnormal repolarization. We characterized QT adaptation during exercise in anorexia. Sixty-one adolescent female patients with anorexia nervosa and 45 age- and sex-matched healthy volunteers performed symptom-limited cycle ergometry during 12-lead ECG monitoring. Changes in the QT interval during exercise were measured, and QT/RR-interval slopes were determined by using mixed-effects regression modeling. Patients had significantly lower body mass index than controls; however, resting heart rates and QT/QTc intervals were similar at baseline. Patients had shorter exercise times (13.7±4.5 versus 20.6±4.5 minutes; P<0.001) and lower peak heart rates (159±20 versus 184±9 beats/min; P<0.001). The mean QTc intervals were longer at peak exercise in patients (442±29 versus 422±19 ms; P<0.001). During submaximal exertion at comparable heart rates (114±6 versus 115±11 beats/min; P=0.54), the QTc interval had prolonged significantly more in patients than controls (37±28 versus 24±25 ms; P<0.016). The RR/QT slope, best described by a curvilinear relationship, was more gradual in patients than in controls (13.4; 95% confidence interval, 12.8-13.9 versus 15.8; 95% confidence interval, 15.3-16.4 ms QT change per 10% change in RR interval; P<0.001) and steepest in patients within the highest body mass index tertile versus the lowest (13.9; 95% confidence interval, 12.9-14.9 versus 12.3; 95% confidence interval, 11.3-13.3; P=0.026). Despite the absence of manifest QT prolongation, adolescent anorexic females have impaired repolarization reserve in comparison with healthy controls. Further study may identify impaired QT dynamics as a risk factor for arrhythmias in anorexia nervosa. © 2016 American Heart Association, Inc.
Accuracy assessment of percent canopy cover, cover type, and size class
H. T. Schreuder; S. Bain; R. C. Czaplewski
2003-01-01
Truth for vegetation cover percent and type is obtained from very large-scale photography (VLSP), stand structure as measured by size classes, and vegetation types from a combination of VLSP and ground sampling. We recommend using the Kappa statistic with bootstrap confidence intervals for overall accuracy, and similarly bootstrap confidence intervals for percent...
ERIC Educational Resources Information Center
Odgaard, Eric C.; Fowler, Robert L.
2010-01-01
Objective: In 2005, the "Journal of Consulting and Clinical Psychology" ("JCCP") became the first American Psychological Association (APA) journal to require statistical measures of clinical significance, plus effect sizes (ESs) and associated confidence intervals (CIs), for primary outcomes (La Greca, 2005). As this represents the single largest…
Optimal and Most Exact Confidence Intervals for Person Parameters in Item Response Theory Models
ERIC Educational Resources Information Center
Doebler, Anna; Doebler, Philipp; Holling, Heinz
2013-01-01
The common way to calculate confidence intervals for item response theory models is to assume that the standardized maximum likelihood estimator for the person parameter [theta] is normally distributed. However, this approximation is often inadequate for short and medium test lengths. As a result, the coverage probabilities fall below the given…
SIMREL: Software for Coefficient Alpha and Its Confidence Intervals with Monte Carlo Studies
ERIC Educational Resources Information Center
Yurdugul, Halil
2009-01-01
This article describes SIMREL, a software program designed for the simulation of alpha coefficients and the estimation of its confidence intervals. SIMREL runs on two alternatives. In the first one, if SIMREL is run for a single data file, it performs descriptive statistics, principal components analysis, and variance analysis of the item scores…
Performing Contrast Analysis in Factorial Designs: From NHST to Confidence Intervals and Beyond
ERIC Educational Resources Information Center
Wiens, Stefan; Nilsson, Mats E.
2017-01-01
Because of the continuing debates about statistics, many researchers may feel confused about how to analyze and interpret data. Current guidelines in psychology advocate the use of effect sizes and confidence intervals (CIs). However, researchers may be unsure about how to extract effect sizes from factorial designs. Contrast analysis is helpful…
Musculoskeletal disorders among Thai women in construction-related work.
Hanklang, Suda; Kaewboonchoo, Orawan; Silpasuwan, Pimpan; Mungarndee, Suriyaphun S
2014-03-01
A cross-sectional study was conducted to determine the prevalence of musculoskeletal disorder symptoms and its risk factors among women rebar workers. A simple random sampling method was used and data were collected by face-to-face interview and ergonomic assessment from February to March 2011. A total of 272 women rebar workers with at least 6 months' job experience participated in this study. The findings revealed that 57.7% of workers reported musculoskeletal disorder symptoms with low back and shoulders as the most common body parts affected (46.0%). Multiple logistic regression analysis indicated 2 variables that are significantly associated with musculoskeletal disorders: prolonged working hours (adjusted odds ratio = 7.63; 95% confidence interval = 2.06-28.31) and awkward posture (adjusted odds ratio = 43.79; 95% confidence interval = 17.09-112.20). The high prevalence of musculoskeletal disorders among women rebar workers suggests that an appropriate ergonomic workstation design and ergonomic training for women rebar workers are necessary.
Liu, S-A; Tung, K-C; Shiao, J-Y; Chiu, Y-T
2008-04-01
The aim of this study was to investigate whether an extended course of prophylactic antibiotic could reduce the wound infection rate in a subtropical country. Fifty-three consecutive cases scheduled to receive major head and neck operations were randomised into one-day or three-day prophylactic antibiotic groups. Thirteen cases (24.5 per cent) developed wound infections after operations. The duration of prophylactic antibiotic was not related to the surgical wound infection. However, pre-operative haemoglobulin less than 10.5 g/dl (odds ratio: 7.24, 95 per cent confidence interval: 1.28-41.0) and reconstruction with a free flap or pectoris major myocutaneous flap during the operation (odds ratio: 11.04, 95 per cent confidence interval: 1.17-104.7) were associated factors significantly influencing post-operative wound infection. Therefore, one day of prophylactic antibiotic was effective in major head and neck procedures but should not be substituted for proper aseptic and meticulous surgical techniques.
Association of cardiac disease and alcohol use with the development of severe ciguatera.
Radke, Elizabeth G; Grattan, Lynn M; Morris, John Glenn
2013-12-01
Ciguatera is a foodborne illness that causes severe gastrointestinal and neurologic symptoms, but the risk factors for illness are not well established. In St Thomas, US Virgin Islands, we performed a case-control study for ciguatera, enrolling 47 patients primarily through the emergency department and 141 age- and sex-matched controls identified through an island-wide survey. We used conditional logistic regression to assess health-related risk factors for ciguatera, including comorbidities and alcohol and tobacco use. Cases were more likely than controls to report alcohol consumption at least weekly (odds ratio 5.7, 95% confidence interval 2.7-24.8). Cases also more frequently had a history of heart disease (odds ratio 6.3, 95% confidence interval 1.2-32.7). Previous ciguatera episodes, lower levels of education, and frequent fish consumption also were associated with illness. This study provides preliminary evidence that preexisting health status influences an individual's risk of developing severe ciguatera. There may be a benefit to educating high-risk individuals about preventing ciguatera.
Jordan, Hannah T; Stellman, Steven D; Prezant, David; Teirstein, Alvin; Osahan, Sukhminder S; Cone, James E
2011-09-01
Explore relationships between World Trade Center (WTC) exposures and sarcoidosis. Sarcoidosis has been reported after exposure to the WTC disaster. We ascertained biopsy-proven post-9/11 sarcoidosis among WTC Health Registry enrollees. Cases diagnosed after Registry enrollment were included in a nested case-control study. Controls were matched to cases on age, sex, race or ethnicity, and eligibility group (eg, rescue or recovery worker). We identified 43 cases of post-9/11 sarcoidosis. Twenty-eight incident cases and 109 controls were included in the case-control analysis. Working on the WTC debris pile was associated with sarcoidosis (odds ratio 9.1, 95% confidence interval 1.1 to 74.0), but WTC dust cloud exposure was not (odds ratio 1.0, 95% confidence interval 0.4 to 2.8). Working on the WTC debris pile was associated with an elevated risk of post-9/11 sarcoidosis. Occupationally exposed workers may be at increased risk. (C)2011The American College of Occupational and Environmental Medicine
Osteosarcoma: A Meta-Analysis and Review of the Literature.
Friebele, Jill C; Peck, Jeffrey; Pan, Xueliang; Abdel-Rasoul, Mahmoud; Mayerson, Joel L
2015-12-01
Over the past 30 years, treatment advances and the addition of neoadjuvant chemotherapy have led to improved 5-year survival in patients with osteosarcoma. More recent literature suggests the overall prognosis remains highly variable, with little improvement since the introduction of neoadjuvant chemotherapy. Tumor necrosis is an important predictor of patient prognosis. Necrosis of more than 90% correlates with overall survival (OS) approaching 75%. We reviewed the history of osteosarcoma treatment and survival and performed a meta-analysis of the 2000-2011 literature. Forty articles were included in the study. Five-year OS was 63% (95% confidence interval, 60%-66%) in studies that included patients with metastatic and nonmetastatic disease and 71% (95% confidence interval, 67%-76%) in studies that included only patients with nonmetastatic disease. Fifty percent of the patients in the studies of those with nonmetastatic osteosarcoma achieved 90% necrosis on histology. Five-year OS and number of patients achieving 90% necrosis are consistent with previous reports. Research is needed to improve treatment regimens and patient outcomes.
Visitor and community survey results for Prime Hook National Wildlife Refuge: Completion report
Sexton, Natalie R.; Stewart, Susan C.; Koontz, Lynne; Ponds, Phadrea; Walters, Katherine D.
2007-01-01
Community residents’ perceptions and opinions Data for this study were collected using a survey administered to visitors to Prime Hook NWR and individuals living in the communities surrounding the Refuge. Surveys were randomly distributed to both consumptive and nonconsumptive use visitors over a one year period (September 2004 to September 2005) to account for seasonal variation in Refuge use. Three hundred thirty-two visitor surveys were returned for a response rate of 80 percent with a confidence interval of ± 5.4. Surveys were also distributed to a stratified random sample of community members in adjacent and surrounding areas (Slaughter Beach, Broadkill Beach, Prime Hook Beach, Milton, Lewes, Milford, and surrounding communities). Four hundred ninety-one surveys from the overall community sample were returned for a response rate of 39 percent with a ± 4.4 confidence interval. Community member results were weighted by U.S. Census Bureau data to correct for age and gender bias, and for community proportionality.
Wang, Zengfang; Wang, Zengyan; Wang, Luang; Qiu, Mingyue; Wang, Yangang; Hou, Xu; Guo, Zhong; Wang, Bin
2017-03-01
Many studies assessed the association between hypertensive disorders during pregnancy and risk of type 2 diabetes mellitus in later life, but contradictory findings were reported. A systemic review and meta-analysis was carried out to elucidate type 2 diabetes mellitus risk in women with hypertensive disorders during pregnancy. Pubmed, Embase, and Web of Science were searched for cohort or case-control studies on the association between hypertensive disorders during pregnancy and subsequent type 2 diabetes mellitus. Random-effect model was used to pool risk estimates. Bayesian meta-analysis was carried out to further estimate the type 2 diabetes mellitus risk associated with hypertensive disorders during pregnancy. Seventeen cohort or prospective matched case-control studies were finally included. Those 17 studies involved 2,984,634 women and 46,732 type 2 diabetes mellitus cases. Overall, hypertensive disorders during pregnancy were significantly correlated with type 2 diabetes mellitus risk (relative risk = 1.56, 95 % confidence interval 1.21-2.01, P = 0.001). Preeclampsia was significantly and independently correlated with type 2 diabetes mellitus risk (relative risk = 2.25, 95 % confidence interval 1.73-2.90, P < 0.001). In addition, gestational hypertension was also significantly and independently correlated with subsequent type 2 diabetes mellitus risk (relative risk = 2.06, 95 % confidence interval 1.57-2.69, P < 0.001). The pooled estimates were not significantly altered in the subgroup analyses of studies on preeclampsia or gestational hypertension. Bayesian meta-analysis showed the relative risks of type 2 diabetes mellitus risk for individuals with hypertensive disorders during pregnancy, preeclampsia, and gestational hypertension were 1.59 (95 % credibility interval: 1.11-2.32), 2.27 (95 % credibility interval: 1.67-2.97), and 2.06 (95 % credibility interval: 1.41-2.84), respectively. Publication bias was not evident in the meta-analysis. Preeclampsia and gestational hypertension are independently associated with substantially elevated risk of type 2 diabetes mellitus in later life.
Lowe, John; Watkins, W John; Edwards, Martin O; Spiller, O Brad; Jacqz-Aigrain, Evelyne; Kotecha, Sarah J; Kotecha, Sailesh
2014-07-01
Previous meta-analyses have reported a significant association between pulmonary colonization with Ureaplasma and development of bronchopulmonary dysplasia (BPD). However, because few studies reporting oxygen dependency at 36 weeks corrected gestation were previously available, we updated the systematic review and meta-analyses to evaluate the association between presence of pulmonary Ureaplasma and development of BPD. Five databases were searched for articles reporting the incidence of BPD at 36 weeks postmenstrual age (BPD36) and/or BPD at 28 days of life (BPD28) in Ureaplasma colonized and noncolonized groups. Pooled estimates were produced using random effects meta-analysis. Meta-regression was used to assess the influence of difference in gestational age between the Ureaplasma-positive and Ureaplasma-negative groups. The effects of potential sources of heterogeneity were also investigated. Of 39 studies included, 8 reported BPD36, 22 reported BPD28 and 9 reported both. The quality of studies was assessed as moderate to good. There was a significant association between Ureaplasma and development of BPD36 (odds ratio = 2.22; 95% confidence intervals: 1.42-3.47) and BPD28 (odds ratio = 3.04; 95% confidence intervals: 2.41-3.83). Sample size influenced the odds ratio, but no significant association was noted between BPD28 rates and difference in gestational age between Ureaplasma colonized and noncolonized infants (P = 0.96). Pulmonary colonization with Ureaplasma continues to be significantly associated with development of BPD in preterm infants at both 36 weeks postmenstrual age and at 28 days of life. This association at BPD28 persists regardless of difference in gestational age.
Frequency of depression in type 2 diabetes mellitus and an analysis of predictive factors.
Arshad, Abdul Rehman; Alvi, Kamran Yousaf
2016-04-01
To determine frequency of depression in patients with diabetes mellitus type 2 and to identify predictive factors. The observational study was carried out at 1 Mountain Medical Battalion, Bagh, Azad Kashmir, Pakistan, from June 2013 to May 2014, and comprised type 2 diabetic patients who were not using anti-depressants and did not have history of other psychiatric illnesses. Demographic data, duration of diabetes, presence of hypertension and type of treatment were recorded and body mass index was calculated. Patient Health Questionnaire-9, translated into Urdu, was administered during face-to-face interviews. Scores >5 indicated depression, which was classified into different grades of severity using standard cut-off values. Of the 133 patients, 51(38.35%) were depressed. Depression was mild in 34(26%), moderate in 12(9.6%), moderately severe in 4(2.9%) and severe in 1(0.7%) patient. On univariate binary logistic regression, female gender (odds ratio=3.07; 95% confidence interval = 1.43, 6.59), lesser education (odds ratio = 0.90; 95% confidence interval 0.84, 0.97) shorter duration of diabetes (odds ratio=0.87; 95% confidence interval = 0.80, 0.96) and higher body mass index (odds ratio=1.41; 95% confidence interval = 1.05, 1.25) were significantly associated with depression. Only shorter duration of diabetes (odds ratio=0.90; 95% confidence interval = 0.82, 0.99) remained significant after adjustment for confounders. Age, level of education, glycaemic control and type of treatment did not predict depression. A significant proportion of type 2 diabetics were depressed. Shorter duration of diabetes reliably predicted depression in these patients.
Kistner, Emily O; Muller, Keith E
2004-09-01
Intraclass correlation and Cronbach's alpha are widely used to describe reliability of tests and measurements. Even with Gaussian data, exact distributions are known only for compound symmetric covariance (equal variances and equal correlations). Recently, large sample Gaussian approximations were derived for the distribution functions. New exact results allow calculating the exact distribution function and other properties of intraclass correlation and Cronbach's alpha, for Gaussian data with any covariance pattern, not just compound symmetry. Probabilities are computed in terms of the distribution function of a weighted sum of independent chi-square random variables. New F approximations for the distribution functions of intraclass correlation and Cronbach's alpha are much simpler and faster to compute than the exact forms. Assuming the covariance matrix is known, the approximations typically provide sufficient accuracy, even with as few as ten observations. Either the exact or approximate distributions may be used to create confidence intervals around an estimate of reliability. Monte Carlo simulations led to a number of conclusions. Correctly assuming that the covariance matrix is compound symmetric leads to accurate confidence intervals, as was expected from previously known results. However, assuming and estimating a general covariance matrix produces somewhat optimistically narrow confidence intervals with 10 observations. Increasing sample size to 100 gives essentially unbiased coverage. Incorrectly assuming compound symmetry leads to pessimistically large confidence intervals, with pessimism increasing with sample size. In contrast, incorrectly assuming general covariance introduces only a modest optimistic bias in small samples. Hence the new methods seem preferable for creating confidence intervals, except when compound symmetry definitely holds.
Sowunmi, Akintunde; Okuboyejo, Titilope M; Gbotosho, Grace O; Happi, Christian T
2011-01-01
Artemisinin-based combination treatments (ACTs) are the recommended first-line antimalarials globally, but their influence on the risk factors associated with gametocyte carriage has had little evaluation in endemic areas. The risk factors associated with gametocytaemia at presentation and after ACTs were evaluated in 835 children assigned to artesunate, artesunate-amodiaquine, artesunate-mefloquine or artemether-lumefantrine. Gametocyte carriage at enrolment was 8.4%. During follow-up, 24 patients (2.8%) developed gametocytaemia, which in 83% (20 patients) had developed by day 7 following treatment. In a multiple regression model, 2 factors were independent risk factors for the presence of gametocytaemia at enrolment, namely age <3 years (adjusted odds ratio 2.03, 95% confidence interval 1.01-4.05; p = 0.04) and enrolment before 2009 (adjusted odds ratio 4.2, 95% confidence interval 2.09-8.44; p < 0.001). Haematocrit <25% and parasitaemia <50,000/μl blood were associated with an increased risk of gametocytaemia. Following treatment, 3 factors were independent risk factors for gametocytaemia, namely gametocytaemia at enrolment (adjusted odds ratio 46.39, 95% confidence interval 22.3-96.46; p < 0.0001) and treatment with artesunate (adjusted odds ratio 6.74, 95% confidence interval 1.79-25.27; p = 0.005) or artesunate-mefloquine (adjusted odds ratio 9.66, 95% confidence interval 2.87-32.46; p < 0.0.0001) relative to other ACTs. ACTs modified the risk factors associated with gametocyte carriage after use. Copyright © 2012 S. Karger AG, Basel.
Weighted regression analysis and interval estimators
Donald W. Seegrist
1974-01-01
A method for deriving the weighted least squares estimators for the parameters of a multiple regression model. Confidence intervals for expected values, and prediction intervals for the means of future samples are given.
Blast Load Simulator Experiments for Computational Model Validation: Report 2
2017-02-01
repeatability. The uncertainty in the experimental pressures and impulses was evaluated by computing 95% confidence intervals on the results. DISCLAIMER: The...Experiment uncertainty The uncertainty in the experimental pressure and impulse was evaluated for the five replicate experiments for which, as closely as...comparisons were made among the replicated experiments to evaluate repeatability. The uncertainty in the experimental pressures and impulses was
Tate, Robyn L; McDonald, Skye; Perdices, Michael; Togher, Leanne; Schultz, Regina; Savage, Sharon
2008-08-01
Rating scales that assess methodological quality of clinical trials provide a means to critically appraise the literature. Scales are currently available to rate randomised and non-randomised controlled trials, but there are none that assess single-subject designs. The Single-Case Experimental Design (SCED) Scale was developed for this purpose and evaluated for reliability. Six clinical researchers who were trained and experienced in rating methodological quality of clinical trials developed the scale and participated in reliability studies. The SCED Scale is an 11-item rating scale for single-subject designs, of which 10 items are used to assess methodological quality and use of statistical analysis. The scale was developed and refined over a 3-year period. Content validity was addressed by identifying items to reduce the main sources of bias in single-case methodology as stipulated by authorities in the field, which were empirically tested against 85 published reports. Inter-rater reliability was assessed using a random sample of 20/312 single-subject reports archived in the Psychological Database of Brain Impairment Treatment Efficacy (PsycBITE). Inter-rater reliability for the total score was excellent, both for individual raters (overall ICC = 0.84; 95% confidence interval 0.73-0.92) and for consensus ratings between pairs of raters (overall ICC = 0.88; 95% confidence interval 0.78-0.95). Item reliability was fair to excellent for consensus ratings between pairs of raters (range k = 0.48 to 1.00). The results were replicated with two independent novice raters who were trained in the use of the scale (ICC = 0.88, 95% confidence interval 0.73-0.95). The SCED Scale thus provides a brief and valid evaluation of methodological quality of single-subject designs, with the total score demonstrating excellent inter-rater reliability using both individual and consensus ratings. Items from the scale can also be used as a checklist in the design, reporting and critical appraisal of single-subject designs, thereby assisting to improve standards of single-case methodology.
Compliance with removable orthodontic appliances.
Shah, Nirmal
2017-12-22
Data sourcesMedline via OVID, PubMed, Cochrane Central Register of Controlled Trials, Web of Science Core Collection, LILACS and BBO databases. Unpublished clinical trials accessed using ClinicalTrials.gov, National Research Register, ProQuest Dissertation and Thesis database.Study selectionTwo authors searched studies from inception until May 2016 without language restrictions. Quantitative and qualitative studies incorporating objective data on compliance with removable appliances, barriers to appliance wear compliance, and interventions to improve compliance were included.Data extraction and synthesisQuality of research was assessed using the Cochrane Collaboration's risk of bias tool, the risk of bias in non-randomised studies of interventions (ROBINS-I), and the mixed methods appraisal tool. Statistical heterogeneity was investigated by examining a graphic display of the estimated compliance levels in conjunction with 95% confidence intervals and quantified using the I-squared statistic. A weighted estimate of objective compliance levels for different appliances in relation to stipulated wear and self-reported levels was also calculated. Risk of publication bias was assessed using funnel plots. Meta-regression was undertaken to assess the relative effects of appliance type on compliance levels.ResultsTwenty-four studies met the inclusion criteria. Of these, 11 were included in the quantitative synthesis. The mean duration of objectively measured wear was considerably lower than stipulated wear time amongst all appliances. Headgear had the greatest discrepancy (5.81 hours, 95% confidence interval, 4.98, 6.64). Self-reported wear time was consistently higher than objectively measured wear time amongst all appliances. Headgear had the greatest discrepancy (5.02 hours, 95% confidence interval, 3.64, 6.40). Two studies found an increase in compliance with headgear and Hawley retainers when patients were aware of monitoring. Five studies found younger age groups to be more compliant than older groups. Three studies also found compliance to be better in the early stages of treatment. Integration between quantitative and qualitative studies was not possible.ConclusionsCompliance with removable orthodontic appliances is suboptimal. Patients wear appliances for considerably less time than stipulated and self-reported. Compliance may be increased when patients are aware of monitoring; however, further research is required to identify effective interventions and possible barriers in order to improve removable orthodontic appliance compliance.
Postpartum contraceptive use among women with a recent preterm birth.
Robbins, Cheryl L; Farr, Sherry L; Zapata, Lauren B; D'Angelo, Denise V; Callaghan, William M
2015-10-01
The objective of the study was to evaluate the associations between postpartum contraception and having a recent preterm birth. Population-based data from the Pregnancy Risk Assessment Monitoring System in 9 states were used to estimate the postpartum use of highly or moderately effective contraception (sterilization, intrauterine device, implants, shots, pills, patch, and ring) and user-independent contraception (sterilization, implants, and intrauterine device) among women with recent live births (2009-2011). We assessed the differences in contraception by gestational age (≤27, 28-33, or 34-36 weeks vs term [≥37 weeks]) and modeled the associations using multivariable logistic regression with weighted data. A higher percentage of women with recent extreme preterm birth (≤27 weeks) reported using no postpartum method (31%) compared with all other women (15-16%). Women delivering extreme preterm infants had a decreased odds of using highly or moderately effective methods (adjusted odds ratio, 0.5; 95% confidence interval, 0.4-0.6) and user-independent methods (adjusted odds ratio, 0.5; 95% confidence interval, 0.4-0.7) compared with women having term births. Wanting to get pregnant was more frequently reported as a reason for contraceptive nonuse by women with an extreme preterm birth overall (45%) compared with all other women (15-18%, P < .0001). Infant death occurred in 41% of extreme preterm births and more than half of these mothers (54%) reported wanting to become pregnant as the reason for contraceptive nonuse. During contraceptive counseling with women who had recent preterm births, providers should address an optimal pregnancy interval and consider that women with recent extreme preterm birth, particularly those whose infants died, may not use contraception because they want to get pregnant. Published by Elsevier Inc.
Arcury, Thomas A; Talton, Jennifer W; Summers, Phillip; Chen, Haiying; Laurienti, Paul J; Quandt, Sara A
2016-02-01
Our aim was to describe alcohol consumption behavior of male Latino migrant farmworkers, compare their alcohol consumption behavior with that of other male Latino immigrants, and determine factors associated with risk for alcohol dependence among Latino immigrant workers. Cross-sectional data were drawn from baseline interviews conducted as part of a larger community-based participatory research project examining the cognitive and neurological outcomes of pesticide exposure. A total of 235 farmworkers and 212 nonfarmworkers completed interviews between May and August 2012. Although 17.5% of the North Carolina Latino farmworkers report never having drunk alcohol, and a total of 34.5% report not having drunk alcohol in the previous 3 months, 48.5% engaged in heavy episodic drinking (HED) in the previous 3 months, and 23.8% frequently engaged in HED during this period. Farmworkers and nonfarmworkers did not differ significantly in alcohol consumption behavior. Farmworkers and nonfarmworkers did differ significantly in each component of the CAGE scale, with 37.9% of farmworkers and 16.0% of nonfarmworkers being at risk for alcohol dependence (p < 0.0001). Significant factors for being at risk for alcohol dependence were stress (odds ratio 1.06, 95% confidence interval 1.03, 1.09) and being a farmworker (odds ratio 3.58, 95% confidence interval 2.12, 6.06). Being married reduced the risk of alcohol dependence (odds ratio 0.45, 95% confidence interval 0.23, 0.87). Latino farmworkers and nonfarmworkers consume relatively large amounts of alcohol and engage in HED at relatively high rates. Latino farmworkers have very high rates of risk for alcohol dependence. Policy changes and public health interventions are needed to address these concerns for a population that is vital to the agricultural economy. Copyright © 2016 by the Research Society on Alcoholism.
Arcury, Thomas A.; Talton, Jennifer W.; Summers, Phillip; Chen, Haiying; Laurienti, Paul J.; Quandt, Sara A.
2015-01-01
Aims To describe alcohol consumption behavior of male Latino migrant farmworkers, compare their alcohol consumption behavior with that of other male Latino immigrants, and determine factors associated with risk for alcohol dependence among Latino immigrant workers. Methods Cross-sectional data were drawn from baseline interviews conducted as part of a larger community-based participatory research project examining the cognitive and neurological outcomes of pesticide exposure. A total of 235 farmworkers and 212 non-farmworkers completed interviews between May and August, 2012. Results Although 17.5% of the North Carolina Latino farmworkers report never having drunk alcohol, and a total of 34.5% report not having drunk alcohol in the previous three months, 48.5% engaged in heavy episodic drinking (HED) in the previous 3 months, and 23.8% frequently engaged in HED during this period. Farmworkers and non-farmworkers did not differ significantly in alcohol consumption behavior. Farmworkers and non-farmworkers did differ significantly in each component of the CAGE scale, with 37.9% of farmworkers and 16.0% of non-farmworkers being at risk for alcohol dependence (p<0.0001). Significant factors for being at risk for alcohol dependence were stress (Odds Ratio 1.06, 95% Confidence Interval 1.03, 1.09) and being a farmworker (Odds Ratio 3.58, 95% Confidence Interval 2.12, 6.06). Being married reduced the risk of alcohol dependence (Odds Ratio 0.45, 95% Confidence Interval 0.39, 0.87). Conclusions Latino farmworkers and non-farmworkers consume relatively large amounts of alcohol and engage in heavy episodic drinking at relatively high rates. Latino farmworkers have very high rates of risk for alcohol dependence. Policy changes and public health interventions are needed to address these concerns for a population that is vital to the agricultural economy. PMID:26842256
Neonatal encephalopathy and socioeconomic status: population-based case-control study.
Blume, Heidi K; Loch, Christian M; Li, Christopher I
2007-07-01
To investigate the association between maternal socioeconomic status and the risk of encephalopathy in full-term newborns. Population-based case-control study. Washington State births from 1994 through 2002 recorded in the linked Washington State Birth Registry and Comprehensive Hospital Abstract Reporting System. Cases (n = 1060) were singleton full-term newborns with Comprehensive Hospital Abstract Reporting System International Classification of Diseases, Ninth Revision diagnoses of seizures, birth asphyxia, central nervous system dysfunction, or cerebral irritability. Control cases (n = 5330) were singleton full-term newborns selected from the same database. Main Exposures Socioeconomic status was defined by median income of the census tract of the mother's residence, number of years of maternal educational achievement, or maternal insurance status. Odds ratios estimating the risk of encephalopathy associated with disadvantaged socioeconomic status were calculated in 3 separate analyses using multivariate adjusted logistic regression. Newborns of mothers living in neighborhoods in which residents have a low median income were at increased risk of encephalopathy compared with newborns in neighborhoods in which residents have a median income more than 3 times the poverty level (adjusted odds ratio, 1.9; 95% confidence interval, 1.5-2.3). There was also a trend for increasing risk of encephalopathy associated with decreasing neighborhood income (P<.001). Newborns of mothers with less than 12 years of educational achievement had a higher risk of encephalopathy compared with newborns of mothers with more than 16 years of educational achievement (adjusted odds ratio, 1.7; 95% confidence interval, 1.3-2.3). Newborns of mothers receiving public insurance also had a higher risk of encephalopathy compared with newborns of mothers who have commercial insurance (adjusted odds ratio, 1.4; 95% confidence interval, 1.2-1.7). Disadvantaged socioeconomic status was independently associated with an increased risk of encephalopathy in full-term newborns. These findings suggest that a mother's socioeconomic status may influence the risk of encephalopathy for her full-term newborn.
Illness Identity: A Novel Predictor for Healthcare Use in Adults With Congenital Heart Disease.
Van Bulck, Liesbet; Goossens, Eva; Luyckx, Koen; Oris, Leen; Apers, Silke; Moons, Philip
2018-05-22
To optimize healthcare use of adults with congenital heart disease, all important predictors of healthcare utilization should be identified. Clinical and psychological characteristics (eg, age and depression) have been found to be associated with healthcare use. However, the concept of illness identity, which assesses the degree to which congenital heart disease is integrated into one's identity, has not yet been investigated in association with healthcare use. Hence, the purpose of the study is to examine the predictive value of illness identity for healthcare use. In this ambispective analytical observational cohort study, 216 adults with congenital heart disease were included. The self-reported Illness Identity Questionnaire was used to assess illness identity states: engulfment, rejection, acceptance, and enrichment. After 1 year, self-reported healthcare use for congenital heart disease or other reasons over the past 6 months was assessed including hospitalizations; visits to general practitioner; visits to medical specialists; and emergency room visits. Binary logistic and negative binomial regression analyses were conducted, adjusting for age, sex, disease complexity, and depressive and anxious symptoms. The more profoundly the heart defect dominated one's identity (ie, engulfment), the more likely this person was to be hospitalized (odds ratio=3.76; 95% confidence interval=1.43-9.86), to visit a medical specialist (odds ratio=2.32; 95% confidence interval=1.35-4.00) or a general practitioner (odds ratio=1.78; 95% confidence interval=1.01-3.17), because of their heart defect. Illness identity, more specifically engulfment, has a unique predictive value for the occurrence of healthcare encounters. This association deserves further investigation, in which the directionality of effects and the contribution of illness identity in terms of preventing inappropriate healthcare use should be determined. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.
Interpregnancy interval and risk of autistic disorder.
Gunnes, Nina; Surén, Pål; Bresnahan, Michaeline; Hornig, Mady; Lie, Kari Kveim; Lipkin, W Ian; Magnus, Per; Nilsen, Roy Miodini; Reichborn-Kjennerud, Ted; Schjølberg, Synnve; Susser, Ezra Saul; Øyen, Anne-Siri; Stoltenberg, Camilla
2013-11-01
A recent California study reported increased risk of autistic disorder in children conceived within a year after the birth of a sibling. We assessed the association between interpregnancy interval and risk of autistic disorder using nationwide registry data on pairs of singleton full siblings born in Norway. We defined interpregnancy interval as the time from birth of the first-born child to conception of the second-born child in a sibship. The outcome of interest was autistic disorder in the second-born child. Analyses were restricted to sibships in which the second-born child was born in 1990-2004. Odds ratios (ORs) were estimated by fitting ordinary logistic models and logistic generalized additive models. The study sample included 223,476 singleton full-sibling pairs. In sibships with interpregnancy intervals <9 months, 0.25% of the second-born children had autistic disorder, compared with 0.13% in the reference category (≥ 36 months). For interpregnancy intervals shorter than 9 months, the adjusted OR of autistic disorder in the second-born child was 2.18 (95% confidence interval 1.42-3.26). The risk of autistic disorder in the second-born child was also increased for interpregnancy intervals of 9-11 months in the adjusted analysis (OR = 1.71 [95% CI = 1.07-2.64]). Consistent with a previous report from California, interpregnancy intervals shorter than 1 year were associated with increased risk of autistic disorder in the second-born child. A possible explanation is depletion of micronutrients in mothers with closely spaced pregnancies.
Zinc supplements for treating thalassaemia and sickle cell disease.
Swe, Kye Mon Min; Abas, Adinegara B L; Bhardwaj, Amit; Barua, Ankur; Nair, N S
2013-06-28
Haemoglobinopathies, inherited disorders of haemoglobin synthesis (thalassaemia) or structure (sickle cell disease), are responsible for significant morbidity and mortality throughout the world. The WHO estimates that, globally, 5% of adults are carriers of a haemoglobin condition, 2.9% are carriers of thalassaemia and 2.3% are carriers of sickle cell disease. Carriers are found worldwide as a result of migration of various ethnic groups to different regions of the world. Zinc is an easily available supplement and intervention programs have been carried out to prevent deficiency in people with thalassaemia or sickle cell anaemia. It is important to evaluate the role of zinc supplementation in the treatment of thalassaemia and sickle cell anaemia to reduce deaths due to complications. To assess the effect of zinc supplementation in the treatment of thalassaemia and sickle cell disease. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings.Date of most recent search: 01 February 2013. Randomised, placebo-controlled trials of zinc supplements for treating thalassaemia or sickle cell disease administered at least once a week for at least a month. Two review authors assessed the eligibility and risk of bias of the included trials, extracted and analysed data and wrote the review. We summarised results using risk ratios or rate ratios for dichotomous data and mean differences for continuous data. We combined trial results where appropriate. We identified nine trials for inclusion with all nine contributing outcome data. Two trials reported on people with thalassaemia (n = 152) and seven on sickle cell anaemia (n = 307).In people with thalassaemia, in one trial, the serum zinc level value showed no difference between the zinc supplemented group and the control group, mean difference 47.40 (95% confidence interval -12.95 to 107.99). Regarding anthropometry, in one trial, height velocity was significantly increased in patients who received zinc supplementation for one to seven years duration, mean difference 3.37 (95% confidence interval 2.36 to 4.38) (total number of participants = 26). In one trial, however, there was no difference in body mass index between treatment groups.Zinc acetate supplementation for three months (in one trial) and one year (in two trials) (total number of participants = 71) was noted to increase the serum zinc level significantly in patients with sickle cell anaemia, mean difference 14.90 (95% confidence interval 6.94 to 22.86) and 20.25 (95% confidence interval 11.73 to 28.77) respectively. There was no significant difference in haemoglobin level between intervention and control groups, at either three months (one trial) or one year (one trial), mean difference 0.06 (95% confidence interval -0.84 to 0.96) and mean difference -0.07 (95% confidence interval -1.40 to 1.26) respectively. Regarding anthropometry, one trial showed no significant changes in body mass index or weight after one year of zinc acetate supplementation. In patients with sickle cell disease, the total number of sickle cell crises at one year were significantly decreased in the zinc sulphate supplemented group as compared to controls, mean difference -2.83 (95% confidence interval -3.51 to -2.15) (total participants 130), but not in zinc acetate group, mean difference 1.54 (95% confidence interval -2.01 to 5.09) (total participants 22). In one trial at three months and another at one year, the total number of clinical infections were significantly decreased in the zinc supplemented group as compared to controls, mean difference 0.05 (95% confidence interval 0.01 - 0.43) (total number of participants = 36), and mean difference -7.64 (95% confidence interval -10.89 to -4.39) (total number of participants = 21) respectively. According to the results, there is no evidence from randomised controlled trials to indicate any benefit of zinc supplementation with regards to serum zinc level in patients with thalassaemia. However, height velocity was noted to increase among those who received this intervention.There is mixed evidence on the benefit of using zinc supplementation in people with sickle cell disease. For instance, there is evidence that zinc supplementation for one year increased the serum zinc levels in patients with sickle cell disease. However, though serum zinc level was raised in patients receiving zinc supplementation, haemoglobin level and anthropometry measurements were not significantly different between groups. Evidence of benefit is seen with the reduction in the number of sickle cell crises among sickle cell patients who received one year of zinc sulphate supplementation and with the reduction in the total number of clinical infections among sickle cell patients who received zinc supplementation for both three months and for one year.The conclusion is based on the data from a small group of trials,which were generally of good quality, with a low risk of bias. The authors recommend that more trials on zinc supplementation in thalassaemia and sickle cell disease be conducted given that the literature has shown the benefits of zinc in these types of diseases.
ERIC Educational Resources Information Center
Raykov, Tenko; Marcoulides, George A.
2015-01-01
A latent variable modeling procedure that can be used to evaluate intraclass correlation coefficients in two-level settings with discrete response variables is discussed. The approach is readily applied when the purpose is to furnish confidence intervals at prespecified confidence levels for these coefficients in setups with binary or ordinal…
Lambert, Ronald J W; Mytilinaios, Ioannis; Maitland, Luke; Brown, Angus M
2012-08-01
This study describes a method to obtain parameter confidence intervals from the fitting of non-linear functions to experimental data, using the SOLVER and Analysis ToolPaK Add-In of the Microsoft Excel spreadsheet. Previously we have shown that Excel can fit complex multiple functions to biological data, obtaining values equivalent to those returned by more specialized statistical or mathematical software. However, a disadvantage of using the Excel method was the inability to return confidence intervals for the computed parameters or the correlations between them. Using a simple Monte-Carlo procedure within the Excel spreadsheet (without recourse to programming), SOLVER can provide parameter estimates (up to 200 at a time) for multiple 'virtual' data sets, from which the required confidence intervals and correlation coefficients can be obtained. The general utility of the method is exemplified by applying it to the analysis of the growth of Listeria monocytogenes, the growth inhibition of Pseudomonas aeruginosa by chlorhexidine and the further analysis of the electrophysiological data from the compound action potential of the rodent optic nerve. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.