Logistic regression for dichotomized counts.

PubMed

Preisser, John S; Das, Kalyan; Benecha, Habtamu; Stamm, John W

2016-12-01

Sometimes there is interest in a dichotomized outcome indicating whether a count variable is positive or zero. Under this scenario, the application of ordinary logistic regression may result in efficiency loss, which is quantifiable under an assumed model for the counts. In such situations, a shared-parameter hurdle model is investigated for more efficient estimation of regression parameters relating to overall effects of covariates on the dichotomous outcome, while handling count data with many zeroes. One model part provides a logistic regression containing marginal log odds ratio effects of primary interest, while an ancillary model part describes the mean count of a Poisson or negative binomial process in terms of nuisance regression parameters. Asymptotic efficiency of the logistic model parameter estimators of the two-part models is evaluated with respect to ordinary logistic regression. Simulations are used to assess the properties of the models with respect to power and Type I error, the latter investigated under both misspecified and correctly specified models. The methods are applied to data from a randomized clinical trial of three toothpaste formulations to prevent incident dental caries in a large population of Scottish schoolchildren. © The Author(s) 2014.

Comments Regarding the Binary Power Law for Heterogeneity of Disease Incidence

USDA-ARS?s Scientific Manuscript database

The binary power law (BPL) has been successfully used to characterize heterogeneity (over dispersion or small-scale aggregation) of disease incidence for many plant pathosystems. With the BPL, the log of the observed variance is a linear function of the log of the theoretical variance for a binomial...

Multilevel Models for Binary Data

ERIC Educational Resources Information Center

Powers, Daniel A.

2012-01-01

The methods and models for categorical data analysis cover considerable ground, ranging from regression-type models for binary and binomial data, count data, to ordered and unordered polytomous variables, as well as regression models that mix qualitative and continuous data. This article focuses on methods for binary or binomial data, which are…

Seroprevalence of HCV and HIV infection among clients of the nation's longest-standing statewide syringe exchange program: A cross-sectional study of Community Health Outreach Work to Prevent AIDS (CHOW).

PubMed

Salek, Thomas P; Katz, Alan R; Lenze, Stacy M; Lusk, Heather M; Li, Dongmei; Des Jarlais, Don C

2017-10-01

The Community Health Outreach Work to Prevent AIDS (CHOW) Project is the first and longest-standing statewide integrated and funded needle and syringe exchange program (SEP) in the US. Initiated on O'ahu in 1990, CHOW expanded statewide in 1993. The purpose of this study is to estimate the prevalences of hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infection, and to characterize risk behaviors associated with infection among clients of a long-standing SEP through the analysis of the 2012 CHOW evaluation data. A cross-sectional sample of 130 CHOW Project clients was selected from January 1, 2012 through December 31, 2012. Questionnaires captured self-reported exposure information. HIV and HCV antibodies were detected via rapid, point-of-care FDA-approved tests. Log-binomial regressions were used to estimate prevalence proportion ratios (PPRs). A piecewise linear log-binomial regression model containing 1 spline knot was used to fit the age-HCV relationship. The estimated seroprevalence of HCV was 67.7% (95% confidence interval [CI]=59.5-75.8%). HIV seroprevalence was 2.3% (95% CI=0-4.9%). Anti-HCV prevalence demonstrated age-specific patterns, ranging from 31.6% through 90.9% in people who inject drugs (PWID) <30 to ≥60 years respectively. Age (continuous/year) prior to spline knot at 51.5 years (adjusted PPR [APPR]=1.03; 95% CI=1.02-1.05) and months exchanging syringes (quartiles) (APPR=1.92; 95% CI=1.3-3.29) were independently associated with anti-HCV prevalence. In Hawai'i, HCV prevalence among PWID is hyperendemic demonstrating age- and SEP duration-specific trends. Relatively low HIV prevalence compared with HCV prevalence reflects differences in transmissibility of these 2 blood-borne pathogens and suggests much greater efficacy of SEP for HIV prevention. Copyright © 2017 Elsevier B.V. All rights reserved.

Factors associated with stigma attitude towards people living with HIV among general individuals in Heilongjiang, Northeast China.

PubMed

Li, Xin; Yuan, Lili; Li, Xiaoxia; Shi, Jingli; Jiang, Liying; Zhang, Chundi; Yang, Xiujing; Zhang, Yeli; Zhao, Donghui; Zhao, Yashuang

2017-02-17

HIV-related stigma always is major obstacles to an effective HIV response worldwide. The effect of HIV-related stigma on HIV prevention and treatment is particularly serious in China. This study was to examine stigma attitude towards people living with HIV/AIDS (PLWHA) among general individuals in Heilongjiang Province, Northeast China and the factors associated with stigma attitude, including socio-demographic factors and HIV/AIDS Knowledge. A cross-sectional survey was carried out in Heilongjiang Province, China. A total of 4050 general individuals with age 15-69 years in four villages in rural areas and two communities in urban areas were drawn using stratified cluster sampling. Standardized questionnaire interviews were administered. Univariate and multivariate log-binomial regression were performed to assess factors affecting stigma attitude towards PLWHA. The proportions of participants holding stigma attitude towards PLWHA were 49.6% among rural respondents and 37.0% among urban respondents (P < 0.001). Multivariate log binomial regression analysis among both rural participants (RR = 0.89, 95% CI: 0.87-0.91, P < 0.001) and urban participants (RR = 0.89, 95% CI: 0.87-0.91, P < 0.001) showed that greater knowledge of HIV transmission misconceptions was significantly associated with lower stigma attitude towards people living with HIV. And among urban participants, higher education level (high school vs. primary school or less: RR = 0.73, 95%CI: 0.62-0.87, P < 0.001; middle school vs. primary school or less: RR = 0.83, 95%CI: 0.71-0.97, P = 0.018) were also significantly associated with lower stigma attitude towards PLWHA. The level of stigma attitude towards PLWHA is higher in rural areas than in urban areas in Heilongjiang. Meanwhile, individuals who better were aware of HIV/AIDS transmission misconceptions may hold lower stigma attitude toward PLWHA whether among rural or urban residents.

A comparison of methods for the analysis of binomial clustered outcomes in behavioral research.

PubMed

Ferrari, Alberto; Comelli, Mario

2016-12-01

In behavioral research, data consisting of a per-subject proportion of "successes" and "failures" over a finite number of trials often arise. This clustered binary data are usually non-normally distributed, which can distort inference if the usual general linear model is applied and sample size is small. A number of more advanced methods is available, but they are often technically challenging and a comparative assessment of their performances in behavioral setups has not been performed. We studied the performances of some methods applicable to the analysis of proportions; namely linear regression, Poisson regression, beta-binomial regression and Generalized Linear Mixed Models (GLMMs). We report on a simulation study evaluating power and Type I error rate of these models in hypothetical scenarios met by behavioral researchers; plus, we describe results from the application of these methods on data from real experiments. Our results show that, while GLMMs are powerful instruments for the analysis of clustered binary outcomes, beta-binomial regression can outperform them in a range of scenarios. Linear regression gave results consistent with the nominal level of significance, but was overall less powerful. Poisson regression, instead, mostly led to anticonservative inference. GLMMs and beta-binomial regression are generally more powerful than linear regression; yet linear regression is robust to model misspecification in some conditions, whereas Poisson regression suffers heavily from violations of the assumptions when used to model proportion data. We conclude providing directions to behavioral scientists dealing with clustered binary data and small sample sizes. Copyright © 2016 Elsevier B.V. All rights reserved.

The arcsine is asinine: the analysis of proportions in ecology.

PubMed

Warton, David I; Hui, Francis K C

2011-01-01

The arcsine square root transformation has long been standard procedure when analyzing proportional data in ecology, with applications in data sets containing binomial and non-binomial response variables. Here, we argue that the arcsine transform should not be used in either circumstance. For binomial data, logistic regression has greater interpretability and higher power than analyses of transformed data. However, it is important to check the data for additional unexplained variation, i.e., overdispersion, and to account for it via the inclusion of random effects in the model if found. For non-binomial data, the arcsine transform is undesirable on the grounds of interpretability, and because it can produce nonsensical predictions. The logit transformation is proposed as an alternative approach to address these issues. Examples are presented in both cases to illustrate these advantages, comparing various methods of analyzing proportions including untransformed, arcsine- and logit-transformed linear models and logistic regression (with or without random effects). Simulations demonstrate that logistic regression usually provides a gain in power over other methods.

Simulation on Poisson and negative binomial models of count road accident modeling

NASA Astrophysics Data System (ADS)

Sapuan, M. S.; Razali, A. M.; Zamzuri, Z. H.; Ibrahim, K.

2016-11-01

Accident count data have often been shown to have overdispersion. On the other hand, the data might contain zero count (excess zeros). The simulation study was conducted to create a scenarios which an accident happen in T-junction with the assumption the dependent variables of generated data follows certain distribution namely Poisson and negative binomial distribution with different sample size of n=30 to n=500. The study objective was accomplished by fitting Poisson regression, negative binomial regression and Hurdle negative binomial model to the simulated data. The model validation was compared and the simulation result shows for each different sample size, not all model fit the data nicely even though the data generated from its own distribution especially when the sample size is larger. Furthermore, the larger sample size indicates that more zeros accident count in the dataset.

Estimating cavity tree and snag abundance using negative binomial regression models and nearest neighbor imputation methods

Treesearch

Bianca N.I. Eskelson; Hailemariam Temesgen; Tara M. Barrett

2009-01-01

Cavity tree and snag abundance data are highly variable and contain many zero observations. We predict cavity tree and snag abundance from variables that are readily available from forest cover maps or remotely sensed data using negative binomial (NB), zero-inflated NB, and zero-altered NB (ZANB) regression models as well as nearest neighbor (NN) imputation methods....

Data mining of tree-based models to analyze freeway accident frequency.

PubMed

Chang, Li-Yen; Chen, Wen-Chieh

2005-01-01

Statistical models, such as Poisson or negative binomial regression models, have been employed to analyze vehicle accident frequency for many years. However, these models have their own model assumptions and pre-defined underlying relationship between dependent and independent variables. If these assumptions are violated, the model could lead to erroneous estimation of accident likelihood. Classification and Regression Tree (CART), one of the most widely applied data mining techniques, has been commonly employed in business administration, industry, and engineering. CART does not require any pre-defined underlying relationship between target (dependent) variable and predictors (independent variables) and has been shown to be a powerful tool, particularly for dealing with prediction and classification problems. This study collected the 2001-2002 accident data of National Freeway 1 in Taiwan. A CART model and a negative binomial regression model were developed to establish the empirical relationship between traffic accidents and highway geometric variables, traffic characteristics, and environmental factors. The CART findings indicated that the average daily traffic volume and precipitation variables were the key determinants for freeway accident frequencies. By comparing the prediction performance between the CART and the negative binomial regression models, this study demonstrates that CART is a good alternative method for analyzing freeway accident frequencies. By comparing the prediction performance between the CART and the negative binomial regression models, this study demonstrates that CART is a good alternative method for analyzing freeway accident frequencies.

Early-life mortality risks in opposite-sex and same-sex twins: a Danish cohort study of the twin testosterone transfer hypothesis

PubMed Central

Ahrenfeldt, Linda Juel; Larsen, Lisbeth Aagaard; Lindahl-Jacobsen, Rune; Skytthe, Axel; Hjelmborg, Jacob v.B.; Möller, Sören; Christensen, Kaare

2017-01-01

Purpose To investigate the twin testosterone transfer (TTT) hypothesis by comparing early-life mortality risks of opposite-sex (OS) and same-sex (SS) twins during the first 15 years of life. Methods We performed a population-based cohort study to compare mortality in OS and SS twins. We included 68,629 live-born Danish twins from 1973 to 2009 identified through the Danish Twin Registry and performed piecewise stratified Cox regression and log-binomial regression. Results Among 1933 deaths, we found significantly higher mortality for twin boys than for twin girls. For both sexes, OS twins had lower mortality than SS twins; the difference persisted for the first year of life for boys and for the first week of life for girls. Conclusions Although the mortality risk for OS boys was in the expected direction according to the TTT hypothesis, the results for OS girls pointed in the opposite direction, providing no clear evidence for the TTT hypothesis. PMID:28024904

Cocoa Farmers’ Compliance with Safety Precautions in Spraying Agrochemicals and Use of Personal Protective Equipment (PPE) in Cameroon

PubMed Central

2018-01-01

The inability of farmers to comply with essential precautions in the course of spraying agrochemicals remains a policy dilemma, especially in developing countries. The objectives of this paper were to assess compliance of cocoa farmers with agrochemical safety measures, analyse the factors explaining involvement of cocoa farmers in the practice of reusing agrochemical containers and wearing of personal protective equipment (PPE). Data were collected with structured questionnaires from 667 cocoa farmers from the Centre and South West regions in Cameroon. Data analyses were carried out with Probit regression and Negative Binomial regression models. The results showed that average cocoa farm sizes were 3.55 ha and 2.82 ha in South West and Centre regions, respectively, and 89.80% and 42.64% complied with manufacturers’ instructions in the use of insecticides. Eating or drinking while spraying insecticides and fungicides was reported by 4.20% and 5.10% of all farmers in the two regions, respectively. However, 37.78% and 57.57% of all farmers wore hand gloves and safety boots while spraying insecticides in the South West and Centre regions of Cameroon, respectively. In addition, 7.80% of all the farmers would wash agrochemical containers and use them at home, while 42.43% would wash and use them on their farms. Probit regression results showed that probability of reusing agrochemical containers was significantly influenced (p < 0.05) by region of residence of cocoa farmers, gender, possession of formal education and farming as primary occupation. The Negative Binomial regression results showed that the log of number PPE worn was significantly influenced (p < 0.10) by region, marital status, attainment of formal education, good health, awareness of manufacturers’ instructions, land area and contact index. It was among others concluded that efforts to train farmers on the need to be familiar with manufacturers’ instructions and use PPE would enhance their safety in the course of spraying agrochemicals. PMID:29438333

Cocoa Farmers' Compliance with Safety Precautions in Spraying Agrochemicals and Use of Personal Protective Equipment (PPE) in Cameroon.

PubMed

Oyekale, Abayomi Samuel

2018-02-13

The inability of farmers to comply with essential precautions in the course of spraying agrochemicals remains a policy dilemma, especially in developing countries. The objectives of this paper were to assess compliance of cocoa farmers with agrochemical safety measures, analyse the factors explaining involvement of cocoa farmers in the practice of reusing agrochemical containers and wearing of personal protective equipment (PPE). Data were collected with structured questionnaires from 667 cocoa farmers from the Centre and South West regions in Cameroon. Data analyses were carried out with Probit regression and Negative Binomial regression models. The results showed that average cocoa farm sizes were 3.55 ha and 2.82 ha in South West and Centre regions, respectively, and 89.80% and 42.64% complied with manufacturers' instructions in the use of insecticides. Eating or drinking while spraying insecticides and fungicides was reported by 4.20% and 5.10% of all farmers in the two regions, respectively. However, 37.78% and 57.57% of all farmers wore hand gloves and safety boots while spraying insecticides in the South West and Centre regions of Cameroon, respectively. In addition, 7.80% of all the farmers would wash agrochemical containers and use them at home, while 42.43% would wash and use them on their farms. Probit regression results showed that probability of reusing agrochemical containers was significantly influenced ( p < 0.05) by region of residence of cocoa farmers, gender, possession of formal education and farming as primary occupation. The Negative Binomial regression results showed that the log of number PPE worn was significantly influenced ( p < 0.10) by region, marital status, attainment of formal education, good health, awareness of manufacturers' instructions, land area and contact index. It was among others concluded that efforts to train farmers on the need to be familiar with manufacturers' instructions and use PPE would enhance their safety in the course of spraying agrochemicals.

Multiple imputation for handling missing outcome data when estimating the relative risk.

PubMed

Sullivan, Thomas R; Lee, Katherine J; Ryan, Philip; Salter, Amy B

2017-09-06

Multiple imputation is a popular approach to handling missing data in medical research, yet little is known about its applicability for estimating the relative risk. Standard methods for imputing incomplete binary outcomes involve logistic regression or an assumption of multivariate normality, whereas relative risks are typically estimated using log binomial models. It is unclear whether misspecification of the imputation model in this setting could lead to biased parameter estimates. Using simulated data, we evaluated the performance of multiple imputation for handling missing data prior to estimating adjusted relative risks from a correctly specified multivariable log binomial model. We considered an arbitrary pattern of missing data in both outcome and exposure variables, with missing data induced under missing at random mechanisms. Focusing on standard model-based methods of multiple imputation, missing data were imputed using multivariate normal imputation or fully conditional specification with a logistic imputation model for the outcome. Multivariate normal imputation performed poorly in the simulation study, consistently producing estimates of the relative risk that were biased towards the null. Despite outperforming multivariate normal imputation, fully conditional specification also produced somewhat biased estimates, with greater bias observed for higher outcome prevalences and larger relative risks. Deleting imputed outcomes from analysis datasets did not improve the performance of fully conditional specification. Both multivariate normal imputation and fully conditional specification produced biased estimates of the relative risk, presumably since both use a misspecified imputation model. Based on simulation results, we recommend researchers use fully conditional specification rather than multivariate normal imputation and retain imputed outcomes in the analysis when estimating relative risks. However fully conditional specification is not without its shortcomings, and so further research is needed to identify optimal approaches for relative risk estimation within the multiple imputation framework.

Period prevalence and factors associated with road traffic crashes among young adults in Kuwait.

PubMed

Aldhafeeri, Eisa; Alshammari, Farah; Jafar, Hana; Malhas, Haya; Botras, Marina; Alnasrallah, Noor; Akhtar, Saeed

2018-05-01

This cross-sectional study assessed one-year period prevalence of road traffic crashes (RTCs) and examined the factors associated with RTCs among young adults in Kuwait. During December 2016, 1500 students enrolled in 15 colleges of Kuwait University were invited to participate in the study. Students 18 years old or older and who drive by themselves were eligible. Data were collected using a structured self-administered questionnaire. One-year period prevalence of RTCs (≥1 vs. none) was computed. Multivariable log-binomial regression model was used to identify the risk factors associated with one-year period prevalence of RTCs. Of 1500 invited individuals, 1465 (97.7%) participated, of which 71.4% (1046/1465) were female, 56.4% (804/1426) were aged between 21 and 25 years, and 67.1% (980/1460) were Kuwaitis. One-year period prevalence of RTC was 38.9%. The final multivariable log-binomial regression model showed that after adjusting for the influences of other variables in the model, participants were more likely to have had at least one RTC during the past year, if they habitually sped over limit (adjusted PR = 1.19; 95% confidence interval (CI): 1.04-1.36), crossed a red light (adjusted PR = 1.33; 95% CI: 1.16-1.52), or if they have had three or more speeding tickets (adjusted PR = 1.40; 95% CI: 1.13-1.73) compared to those who reportedly had no RTC during the same period. One-year period prevalence of RTCs among university students in Kuwait, though relatively lower than the reported figures in similar populations elsewhere in the region, is yet high enough to warrant diligent attention. Habitual speeding, having had three or more speeding tickets, and the practice of crossing a red light were significantly and independently associated with at least one RTC during the past year. Targeted education and enforcement of existing traffic laws may reduce the RTCs frequency in this relatively young population. Future studies may look at impact of such interventions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Selecting the right statistical model for analysis of insect count data by using information theoretic measures.

PubMed

Sileshi, G

2006-10-01

Researchers and regulatory agencies often make statistical inferences from insect count data using modelling approaches that assume homogeneous variance. Such models do not allow for formal appraisal of variability which in its different forms is the subject of interest in ecology. Therefore, the objectives of this paper were to (i) compare models suitable for handling variance heterogeneity and (ii) select optimal models to ensure valid statistical inferences from insect count data. The log-normal, standard Poisson, Poisson corrected for overdispersion, zero-inflated Poisson, the negative binomial distribution and zero-inflated negative binomial models were compared using six count datasets on foliage-dwelling insects and five families of soil-dwelling insects. Akaike's and Schwarz Bayesian information criteria were used for comparing the various models. Over 50% of the counts were zeros even in locally abundant species such as Ootheca bennigseni Weise, Mesoplatys ochroptera Stål and Diaecoderus spp. The Poisson model after correction for overdispersion and the standard negative binomial distribution model provided better description of the probability distribution of seven out of the 11 insects than the log-normal, standard Poisson, zero-inflated Poisson or zero-inflated negative binomial models. It is concluded that excess zeros and variance heterogeneity are common data phenomena in insect counts. If not properly modelled, these properties can invalidate the normal distribution assumptions resulting in biased estimation of ecological effects and jeopardizing the integrity of the scientific inferences. Therefore, it is recommended that statistical models appropriate for handling these data properties be selected using objective criteria to ensure efficient statistical inference.

Morbidity and Health Risk Factors Among New Mexico Miners: A Comparison Across Mining Sectors.

PubMed

Shumate, Alice M; Yeoman, Kristin; Victoroff, Tristan; Evans, Kandace; Karr, Roger; Sanchez, Tami; Sood, Akshay; Laney, Anthony Scott

2017-08-01

This study examines differences in chronic health outcomes between coal, uranium, metal, and nonmetal miners. In a cross-sectional study using data from a health screening program for current and former New Mexico miners, log-binomial logistic regression models were used to estimate relative risks of respiratory and heart disease, cancer, osteoarthritis, and back pain associated with mining in each sector as compared with coal, adjusting for other relevant risk factors. Differential risks in angina, pulmonary symptoms, asthma, cancer, osteoarthritis, and back pain between mining sectors were found. New Mexico miners experience different chronic health challenges across sectors. These results demonstrate the importance of using comparable data to understand how health risks differ across mining sectors. Further investigation among a broader geographic population of miners will help identify the health priorities and needs in each sector.

Employee resistance and injury during commercial robberies.

PubMed

Jones, Jennifer; Casteel, Carri; Peek-Asa, Corinne

2015-05-01

To examine the association between employee resistance and injury and examine whether type or location of property stolen was associated with employee resistance during commercial robberies in a large metropolitan city. Robbery data were abstracted from police crime reports between 2008 and 2012. Log binomial regression models were used to identify predictors of employee resistance and to evaluate the association between employee resistance and injury. Employees resisted a robber in nearly half of all robbery events. Active employee resistance was significantly associated with employee injury (Adj PR: 1.49, 95% confidence interval, 1.34 to 1.65). Goods being stolen were associated with active employee resistance and employee injury, whereas cash only being stolen was inversely associated with employee injury. Results suggest that employee training in nonresistance can be an important strategy in protecting employees working with the exchange of cash and goods.

Neighborhood educational disparities in active commuting among women: the effect of distance between the place of residence and the place of work/study (an ACTI-Cités study).

PubMed

Perchoux, Camille; Nazare, Julie-Anne; Benmarhnia, Tarik; Salze, Paul; Feuillet, Thierry; Hercberg, Serge; Hess, Franck; Menai, Mehdi; Weber, Christiane; Charreire, Hélène; Enaux, Christophe; Oppert, Jean-Michel; Simon, Chantal

2017-06-12

Active transportation has been associated with favorable health outcomes. Previous research highlighted the influence of neighborhood educational level on active transportation. However, little is known regarding the effect of commuting distance on social disparities in active commuting. In this regard, women have been poorly studied. The objective of this paper was to evaluate the relationship between neighborhood educational level and active commuting, and to assess whether the commuting distance modifies this relationship in adult women. This cross-sectional study is based on a subsample of women from the Nutrinet-Santé web-cohort (N = 1169). Binomial, log-binomial and negative binomial regressions were used to assess the associations between neighborhood education level and (i) the likelihood of reporting any active commuting time, and (ii) the share of commuting time made by active transportation modes. Potential effect measure modification of distance to work on the previous associations was assessed both on the additive and the multiplicative scales. Neighborhood education level was positively associated with the probability of reporting any active commuting time (relative risk = 1.774; p < 0.05) and the share of commuting time spent active (relative risk = 1.423; p < 0.05). The impact of neighborhood education was greater at long distances to work for both outcomes. Our results suggest that neighborhood educational disparities in active commuting tend to increase with commuting distance among women. Further research is needed to provide geographically driven guidance for health promotion intervention aiming at reducing disparities in active transportation among socioeconomic groups.

Early-life mortality risks in opposite-sex and same-sex twins: a Danish cohort study of the twin testosterone transfer hypothesis.

PubMed

Ahrenfeldt, Linda Juel; Larsen, Lisbeth Aagaard; Lindahl-Jacobsen, Rune; Skytthe, Axel; Hjelmborg, Jacob V B; Möller, Sören; Christensen, Kaare

2017-02-01

To investigate the twin testosterone transfer (TTT) hypothesis by comparing early-life mortality risks of opposite-sex (OS) and same-sex (SS) twins during the first 15 years of life. We performed a population-based cohort study to compare mortality in OS and SS twins. We included 68,629 live-born Danish twins from 1973 to 2009 identified through the Danish Twin Registry and performed piecewise stratified Cox regression and log-binomial regression. Among 1933 deaths, we found significantly higher mortality for twin boys than for twin girls. For both sexes, OS twins had lower mortality than SS twins; the difference persisted for the first year of life for boys and for the first week of life for girls. Although the mortality risk for OS boys was in the expected direction according to the TTT hypothesis, the results for OS girls pointed in the opposite direction, providing no clear evidence for the TTT hypothesis. Copyright © 2016 Elsevier Inc. All rights reserved.

Prevalence and risk factors of musculoskeletal disorders among Sri Lankan rubber tappers

PubMed Central

de Silva, Vijitha; Tharindra, Hemajith; Ostbye, Truls

2016-01-01

Background Rubber tapping exposes workers to risk factors for musculoskeletal disorders (MSDs). Objectives This cross-sectional study assessed the prevalence and factors associated with MSDs among Sri Lankan rubber tappers. Methods Questionnaires were administered to 300 rubber tappers to measure MSDs and potential associated factors. Ergonomic exposure levels were measured for 90 tappers using the Quick Exposure Check instrument. MSD prevalence and prevalence ratios were calculated using log-binomial regression. Results In the past 12 months, 66% of rubber tappers in our sample experienced an MSD. Ergonomic exposure levels were high or very high in the back (94.4%), shoulders (96.7%), and neck (83.3%). Being female, older, Tamil, working two jobs, alternating tapping hands, and depression were significantly associated with increased risk of MSDs. Conclusions MSDs are common among rubber tappers in Sri Lanka. These results suggest a need for work process modifications to prevent MSDs. PMID:27092589

Applied Prevalence Ratio estimation with different Regression models: An example from a cross-national study on substance use research.

PubMed

Espelt, Albert; Marí-Dell'Olmo, Marc; Penelo, Eva; Bosque-Prous, Marina

2016-06-14

To examine the differences between Prevalence Ratio (PR) and Odds Ratio (OR) in a cross-sectional study and to provide tools to calculate PR using two statistical packages widely used in substance use research (STATA and R). We used cross-sectional data from 41,263 participants of 16 European countries participating in the Survey on Health, Ageing and Retirement in Europe (SHARE). The dependent variable, hazardous drinking, was calculated using the Alcohol Use Disorders Identification Test - Consumption (AUDIT-C). The main independent variable was gender. Other variables used were: age, educational level and country of residence. PR of hazardous drinking in men with relation to women was estimated using Mantel-Haenszel method, log-binomial regression models and poisson regression models with robust variance. These estimations were compared to the OR calculated using logistic regression models. Prevalence of hazardous drinkers varied among countries. Generally, men have higher prevalence of hazardous drinking than women [PR=1.43 (1.38-1.47)]. Estimated PR was identical independently of the method and the statistical package used. However, OR overestimated PR, depending on the prevalence of hazardous drinking in the country. In cross-sectional studies, where comparisons between countries with differences in the prevalence of the disease or condition are made, it is advisable to use PR instead of OR.

A semi-nonparametric Poisson regression model for analyzing motor vehicle crash data.

PubMed

Ye, Xin; Wang, Ke; Zou, Yajie; Lord, Dominique

2018-01-01

This paper develops a semi-nonparametric Poisson regression model to analyze motor vehicle crash frequency data collected from rural multilane highway segments in California, US. Motor vehicle crash frequency on rural highway is a topic of interest in the area of transportation safety due to higher driving speeds and the resultant severity level. Unlike the traditional Negative Binomial (NB) model, the semi-nonparametric Poisson regression model can accommodate an unobserved heterogeneity following a highly flexible semi-nonparametric (SNP) distribution. Simulation experiments are conducted to demonstrate that the SNP distribution can well mimic a large family of distributions, including normal distributions, log-gamma distributions, bimodal and trimodal distributions. Empirical estimation results show that such flexibility offered by the SNP distribution can greatly improve model precision and the overall goodness-of-fit. The semi-nonparametric distribution can provide a better understanding of crash data structure through its ability to capture potential multimodality in the distribution of unobserved heterogeneity. When estimated coefficients in empirical models are compared, SNP and NB models are found to have a substantially different coefficient for the dummy variable indicating the lane width. The SNP model with better statistical performance suggests that the NB model overestimates the effect of lane width on crash frequency reduction by 83.1%.

Differences in spousal influence on smoking cessation by gender and education among Japanese couples.

PubMed

Takagi, Daisuke; Kondo, Naoki; Takada, Misato; Hashimoto, Hideki

2014-11-19

Previous studies have reported that spousal non-smoking has a spillover effect on the partner's cessation. However, discussion is lacking on the factors modifying that association. We examined whether the spillover effect of spousal non-smoking was associated with the couple's educational attainment. We used paired marital data from the Japanese Study on Stratification, Health, Income, and Neighborhood (J-SHINE), which targeted residents aged 25-50 years in four Japanese municipalities. We selected a spouse smoker at the time of marriage (target respondent), and set his/her smoking status change (continued or quit smoking after marriage) as an outcome, regressed on the counterpart's smoking status (continued smoking or non-smoking) and combinations of each couple's educational attainment as explanatory variables using log-binomial regression models (n =1001 targets; 708 men and 293 women). Regression results showed that a counterpart who previously quit smoking or was a never-smoker was associated with the target male spouse's subsequent cessation. However, for women, the association between husband's non-smoking and their own cessation was significant only for couples in which both spouses were highly educated. Our findings suggest that a spouse's smoking status is important for smoking cessation interventions in men. For women, however, a couple's combined educational attainment may matter in the interventions.

Narrow log-periodic modulations in non-Markovian random walks

NASA Astrophysics Data System (ADS)

Diniz, R. M. B.; Cressoni, J. C.; da Silva, M. A. A.; Mariz, A. M.; de Araújo, J. M.

2017-12-01

What are the necessary ingredients for log-periodicity to appear in the dynamics of a random walk model? Can they be subtle enough to be overlooked? Previous studies suggest that long-range damaged memory and negative feedback together are necessary conditions for the emergence of log-periodic oscillations. The role of negative feedback would then be crucial, forcing the system to change direction. In this paper we show that small-amplitude log-periodic oscillations can emerge when the system is driven by positive feedback. Due to their very small amplitude, these oscillations can easily be mistaken for numerical finite-size effects. The models we use consist of discrete-time random walks with strong memory correlations where the decision process is taken from memory profiles based either on a binomial distribution or on a delta distribution. Anomalous superdiffusive behavior and log-periodic modulations are shown to arise in the large time limit for convenient choices of the models parameters.

A Model Comparison for Count Data with a Positively Skewed Distribution with an Application to the Number of University Mathematics Courses Completed

ERIC Educational Resources Information Center

Liou, Pey-Yan

2009-01-01

The current study examines three regression models: OLS (ordinary least square) linear regression, Poisson regression, and negative binomial regression for analyzing count data. Simulation results show that the OLS regression model performed better than the others, since it did not produce more false statistically significant relationships than…

Population heterogeneity in the salience of multiple risk factors for adolescent delinquency.

PubMed

Lanza, Stephanie T; Cooper, Brittany R; Bray, Bethany C

2014-03-01

To present mixture regression analysis as an alternative to more standard regression analysis for predicting adolescent delinquency. We demonstrate how mixture regression analysis allows for the identification of population subgroups defined by the salience of multiple risk factors. We identified population subgroups (i.e., latent classes) of individuals based on their coefficients in a regression model predicting adolescent delinquency from eight previously established risk indices drawn from the community, school, family, peer, and individual levels. The study included N = 37,763 10th-grade adolescents who participated in the Communities That Care Youth Survey. Standard, zero-inflated, and mixture Poisson and negative binomial regression models were considered. Standard and mixture negative binomial regression models were selected as optimal. The five-class regression model was interpreted based on the class-specific regression coefficients, indicating that risk factors had varying salience across classes of adolescents. Standard regression showed that all risk factors were significantly associated with delinquency. Mixture regression provided more nuanced information, suggesting a unique set of risk factors that were salient for different subgroups of adolescents. Implications for the design of subgroup-specific interventions are discussed. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Olfactory function and neurocognitive outcomes in old age: The Atherosclerosis Risk in Communities Neurocognitive Study.

PubMed

Palta, Priya; Chen, Honglei; Deal, Jennifer A; Sharrett, A Richey; Gross, Alden; Knopman, David; Griswold, Michael; Heiss, Gerardo; Mosley, Thomas H

2018-03-30

We tested the hypothesis that poor sense of smell is associated with lower cognitive function and higher mild cognitive impairment (MCI) prevalence. Olfaction, measured by the Sniffin' Sticks test, was categorized as olfactory impairment (OI) (score ≤6) or no OI (score >6). MCI was adjudicated based on review of a neuropsychological examination. Linear regression estimated the mean difference in cognitive factor scores, and log-binomial regression quantified MCI prevalence among participants with versus without OI. Participants with OI had lower mean factor scores (memory: -0.27 standard deviation [SD], 95% confidence interval [CI]: -0.35 to -0.19; language: -0.24 SD, 95% CI: -0.30 to -0.17; executive function/processing speed: -0.09 SD, 95% CI: -0.12 to -0.06; and general cognitive performance: -0.25 SD, 95% CI: -0.30 to -0.20). OI was also associated with MCI (n = 204; prevalence ratio = 1.56, 95% CI: 1.37, 1.78). An impaired sense of smell may serve as a readily accessible early marker of neurodegeneration and improve upon the prevailing delayed diagnoses and underascertainment of MCI/dementia. Copyright © 2018 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Resistant to the recession: low-income adults' maintenance of cooking and away-from-home eating behaviors during times of economic turbulence.

PubMed

Smith, Lindsey P; Ng, Shu Wen; Popkin, Barry M

2014-05-01

We examined the effects of state-level unemployment rates during the recession of 2008 on patterns of home food preparation and away-from-home (AFH) eating among low-income and minority populations. We analyzed pooled cross-sectional data on 118 635 adults aged 18 years or older who took part in the American Time Use Study. Multinomial logistic regression models stratified by gender were used to evaluate the associations between state-level unemployment, poverty, race/ethnicity, and time spent cooking, and log binomial regression was used to assess respondents' AFH consumption patterns. High state-level unemployment was associated with only trivial increases in respondents' cooking patterns and virtually no change in their AFH eating patterns. Low-income and racial/ethnic minority groups were not disproportionately affected by the recession. Even during a major economic downturn, US adults are resistant to food-related behavior change. More work is needed to understand whether this reluctance to change is attributable to time limits, lack of knowledge or skill related to food preparation, or lack of access to fresh produce and raw ingredients.

Resistant to the Recession: Low-Income Adults’ Maintenance of Cooking and Away-From-Home Eating Behaviors During Times of Economic Turbulence

PubMed Central

Smith, Lindsey P.; Ng, Shu Wen

2014-01-01

Objectives. We examined the effects of state-level unemployment rates during the recession of 2008 on patterns of home food preparation and away-from-home (AFH) eating among low-income and minority populations. Methods. We analyzed pooled cross-sectional data on 118 635 adults aged 18 years or older who took part in the American Time Use Study. Multinomial logistic regression models stratified by gender were used to evaluate the associations between state-level unemployment, poverty, race/ethnicity, and time spent cooking, and log binomial regression was used to assess respondents’ AFH consumption patterns. Results. High state-level unemployment was associated with only trivial increases in respondents’ cooking patterns and virtually no change in their AFH eating patterns. Low-income and racial/ethnic minority groups were not disproportionately affected by the recession. Conclusions. Even during a major economic downturn, US adults are resistant to food-related behavior change. More work is needed to understand whether this reluctance to change is attributable to time limits, lack of knowledge or skill related to food preparation, or lack of access to fresh produce and raw ingredients. PMID:24625145

Albumin, a marker for post-operative myocardial damage in cardiac surgery.

PubMed

van Beek, Dianne E C; van der Horst, Iwan C C; de Geus, A Fred; Mariani, Massimo A; Scheeren, Thomas W L

2018-06-06

Low serum albumin (SA) is a prognostic factor for poor outcome after cardiac surgery. The aim of this study was to estimate the association between pre-operative SA, early post-operative SA and postoperative myocardial injury. This single center cohort study included adult patients undergoing cardiac surgery during 4 consecutive years. Postoperative myocardial damage was defined by calculating the area under the curve (AUC) of troponin (Tn) values during the first 72 h after surgery and its association with SA analyzed using linear regression and with multivariable linear regression to account for patient related and procedural confounders. The association between SA and the secondary outcomes (peri-operative myocardial infarction [PMI], requiring ventilation >24 h, rhythm disturbances, 30-day mortality) was studied using (multivariable) log binomial regression analysis. In total 2757 patients were included. The mean pre-operative SA was 29 ± 13 g/l and the mean post-operative SA was 26 ± 6 g/l. Post-operative SA levels (on average 26 min after surgery) were inversely associated with postoperative myocardial damage in both univariable analysis (regression coefficient - 0.019, 95%CI -0.022/-0.015, p < 0.005) and after adjustment for patient related and surgical confounders (regression coefficient - 0.014 [95% CI -0.020/-0.008], p < 0.0005). Post-operative albumin levels were significantly correlated with the amount of postoperative myocardial damage in patients undergoing cardiac surgery independent of typical confounders. Copyright © 2018. Published by Elsevier Inc.

Influence of physician factors on the effectiveness of a continuing medical education intervention.

PubMed

Flores, Sergio; Reyes, Hortensia; Perez-Cuevas, Ricardo

2006-01-01

Continuing medical education (CME) is essential for improving the quality of care in primary health care settings. This study's objective was to determine how the characteristics of family physicians influenced the effectiveness of a multifaceted CME intervention to improve the management of acute respiratory infection (ARI) or type 2 diabetes (DM2). A secondary analysis was conducted based on data from 121 family physicians, who participated in the educational intervention study. The outcome variable was positive change in physician's performance for treatment of ARI or DM2. The exposure variable was multifaceted CME intervention. Independent variables were professional physicians and organizational characteristics. Analysis included log binomial regression modeling. Factors influencing positive change included, for ARI, participation in the CME intervention and medical director interested in that condition and for DM2, participation in the CME intervention, medical director interested in DM2, and being a teacher. Physicians' characteristics and organizational environment influence the effectiveness of educational intervention and are therefore relevant to the implementation of CME strategies.

Novelty helmet use and motorcycle rider fatality

PubMed Central

Rice, Thomas M.; Troszak, Lara; Erhardt, Taryn; Trent, Roger B.; Zhu, Motao

2018-01-01

Objectives To compare the risk of fatal injury across helmet types among collision-involved motorcyclists. Methods We used data from a cohort of motorcyclists involved in police-reported traffic collisions. Eighty-four law enforcement agencies in California collected detailed information on helmet and rider characteristics during collision investigations in June 2012 through July 2013. Multiply-adjusted risk ratios were estimated with log-binomial regression. Results The adjusted fatal injury risk ratio for novelty helmets was 1.95 (95% CI 1.11–3.40, p 0.019), comparing novelty helmets with full-face helmets. The risk ratios for modular, open-face, and half-helmets, compared with full-face helmets, were not significant. Conclusions A more complete understanding of the inadequacy of novelty helmets can be used in educational and law enforcement countermeasures to improve helmet use among motorcycling populations in California and other US states. Law enforcement approaches to mitigating novelty helmet use would seem attractive given that novelty helmets can be visually identified by law enforcement officers with sufficient training. PMID:28431344

Contact dermatitis is an unrecognized problem in the construction industry: Comparison of four different assessment methods.

PubMed

Timmerman, Johan G; Heederik, Dick; Spee, Ton; van Rooy, Frits G; Krop, Esmeralda J M; Rustemeyer, Thomas; Smit, Lidwien A M

2017-10-01

A high contact dermatitis symptoms prevalence has been observed in Dutch construction workers. Contact dermatitis was diagnosed by an expert panel using questionnaire data and photographs of 751 subjects' hands. A subset was evaluated by two occupational physicians. Their diagnoses were compared to those of the expert panel. In addition, two self-reported questionnaire-based assessment methods were compared to the expert panel evaluation. Associations between contact dermatitis and determinants were assessed using log-binomial regression analysis. Contact dermatitis prevalence was high: 61.4% (expert panel's diagnosis) and 32.9% (self-reported). Agreement between occupational physicians and the expert panel was low but increased after training. Washing hands with solvents and performing job-related tasks at home were related to contact dermatitis. Contact dermatitis prevalence among construction workers is high. Recognition of contact dermatitis by occupational physicians is poor but can be improved by training. Awareness of skin disorders should be raised. © 2017 Wiley Periodicals, Inc.

Syphilis Among U.S.-Bound Refugees, 2009-2013.

PubMed

Nyangoma, E N; Olson, C K; Painter, J A; Posey, D L; Stauffer, W M; Naughton, M; Zhou, W; Kamb, M; Benoit, S R

2017-08-01

U.S. immigration regulations require clinical and serologic screening for syphilis for all U.S.-bound refugees 15 years of age and older. We reviewed syphilis screening results for all U.S.-bound refugees from January 1, 2009 through December 31, 2013. We calculated age-adjusted prevalence by region and nationality and assessed factors associated with syphilis seropositivity using multivariable log binomial regression models. Among 233,446 refugees, we identified 874 syphilis cases (373 cases per 100,000 refugees). The highest overall age-adjusted prevalence rates of syphilis seropositivity were observed among refugees from Africa (1340 cases per 100,000), followed by East Asia and the Pacific (397 cases per 100,000). In most regions, male sex, increasing age, and living in non-refugee camp settings were associated with syphilis seropositivity. Future analysis of test results, stage of infection, and treatment delivery overseas is warranted in order to determine the extent of transmission risk and benefits of the screening program.

Individual, network, and neighborhood correlates of exchange sex among female non-injection drug users in Baltimore, MD (2005–2007)

PubMed Central

Rudolph, Abby E; Linton, Sabriya; Dyer, Typhanye Penniman; Latkin, Carl

2012-01-01

The “HIV risk environment” has been characterized as a dynamic interplay between structural and network factors. However, most HIV prevention research has not examined the independent and combined impact of network and structural factors. We aimed to identify individual, network, and neighborhood correlates of exchange sex (≥1 exchange sex partner, past 90 days) among female non-injection drug users (NIDUs). We used baseline data from 417 NIDUs enrolled in a randomized HIV prevention trial in Baltimore (2005–2007). Surveys ascertained demographic variables, drug/sex risk behaviors, neighborhood perceptions, and social/sexual network characteristics. Correlates of exchange sex were identified with descriptive statistics and log-binomial regression. Our findings suggest that sex and drug relationships among female NIDUs are interlinked and may be difficult to modify without altering social norms. Strengthening ties that provide social support but not drug support and reducing ties that provide both drug and social support may facilitate reductions in individual-level HIV-risk behaviors. PMID:22983502

[Multidimensional measurement of precarious employment: social distribution and its association with health in Catalonia (Spain)].

PubMed

Benach, Joan; Julià, Mireia; Tarafa, Gemma; Mir, Jordi; Molinero, Emilia; Vives, Alejandra

2015-01-01

To show the prevalence of precarious employment in Catalonia (Spain) for the first time and its association with mental and self-rated health, measured with a multidimensional scale. A cross-sectional study was conducted using data from the II Catalan Working Conditions Survey (2010) with a subsample of employed workers with a contract. The prevalence of precarious employment using a multidimensional scale and its association with health was calculated using multivariate log-binomial regression stratified by gender. The prevalence of precarious employment in Catalonia was high (42.6%). We found higher precariousness in women, youth, immigrants, and manual and less educated workers. There was a positive gradient in the association between precarious employment and poor health. Precarious employment is associated with poor health in the working population. Working conditions surveys should include questions on precarious employment and health indicators, which would allow monitoring and subsequent analyses of health inequalities. Copyright © 2015 SESPAS. Published by Elsevier Espana. All rights reserved.

Contingency Management Voucher Redemption as an Indicator of Delayed Gratification

PubMed Central

Fletcher, Jesse B.; Dierst-Davies, Rhodri; Reback, Cathy J.

2014-01-01

This prospective analysis tested whether frequency of voucher redemptions during a contingency management (CM) substance use intervention was significantly associated with participants’ ongoing substance use. Homeless, substance-dependent men who have sex with men (N=131) were randomized into either a “full” or “lite” voucher-based CM intervention. All participants earned vouchers for attendance and participation; participants in the CM-full condition also received vouchers for substance abstinence and enactment of prosocial and/or health-promoting behaviors. Multivariate longitudinal negative binomial regression analyses (n = 118) assessed the association between substance use during the intervention and frequency of voucher redemptions. Participants who used methamphetamine (IRR = 0.66; 95% CI=0.44–0.99) and/or opiates (IRR=0.60; 95% CI=0.40–0.99) during the intervention exhibited less time between voucher redemptions than individuals who achieved abstinence from these substances. Voucher redemption logs can be cost-effective and unobtrusive tools for measuring study participants’ tendency to delay gratification. PMID:24674235

[Distribution of individuals by spontaneous frequencies of lymphocytes with micronuclei. Particularity and consequences].

PubMed

Serebrianyĭ, A M; Akleev, A V; Aleshchenko, A V; Antoshchina, M M; Kudriashova, O V; Riabchenko, N I; Semenova, L P; Pelevina, I I

2011-01-01

By micronucleus (MN) assay with cytokinetic cytochalasin B block, the mean frequency of blood lymphocytes with MN has been determined in 76 Moscow inhabitants, 35 people from Obninsk and 122 from Chelyabinsk region. In contrast to the distribution of individuals on spontaneous frequency of cells with aberrations, which was shown to be binomial (Kusnetzov et al., 1980), the distribution of individuals on the spontaneous frequency of cells with MN in all three massif can be acknowledged as log-normal (chi2 test). Distribution of individuals in the joined massifs (Moscow and Obninsk inhabitants) and in the unique massif of all inspected with great reliability must be acknowledged as log-normal (0.70 and 0.86 correspondingly), but it cannot be regarded as Poisson, binomial or normal. Taking into account that log-normal distribution of children by spontaneous frequency of lymphocytes with MN has been observed by the inspection of 473 children from different kindergartens in Moscow we can make the conclusion that log-normal is regularity inherent in this type of damage of lymphocytes genome. On the contrary the distribution of individuals on induced by irradiation in vitro lymphocytes with MN frequency in most cases must be acknowledged as normal. This distribution character points out that damage appearance in the individual (genomic instability) in a single lymphocytes increases the probability of the damage appearance in another lymphocytes. We can propose that damaged stem cells lymphocyte progenitor's exchange by information with undamaged cells--the type of the bystander effect process. It can also be supposed that transmission of damage to daughter cells occurs in the time of stem cells division.

Football goal distributions and extremal statistics

NASA Astrophysics Data System (ADS)

Greenhough, J.; Birch, P. C.; Chapman, S. C.; Rowlands, G.

2002-12-01

We analyse the distributions of the number of goals scored by home teams, away teams, and the total scored in the match, in domestic football games from 169 countries between 1999 and 2001. The probability density functions (PDFs) of goals scored are too heavy-tailed to be fitted over their entire ranges by Poisson or negative binomial distributions which would be expected for uncorrelated processes. Log-normal distributions cannot include zero scores and here we find that the PDFs are consistent with those arising from extremal statistics. In addition, we show that it is sufficient to model English top division and FA Cup matches in the seasons of 1970/71-2000/01 on Poisson or negative binomial distributions, as reported in analyses of earlier seasons, and that these are not consistent with extremal statistics.

The role of obesity in the relation between total water intake and urine osmolality in US adults, 2009-2012.

PubMed

Rosinger, Asher Y; Lawman, Hannah G; Akinbami, Lara J; Ogden, Cynthia L

2016-12-01

Adequate water intake is critical to physiologic and cognitive functioning. Although water requirements increase with body size, it remains unclear whether weight status modifies the relation between water intake and hydration status. We examined how the association between water intake and urine osmolality, which is a hydration biomarker, varied by weight status. NHANES cross-sectional data (2009-2012) were analyzed in 9601 nonpregnant adults aged ≥20 y who did not have kidney failure. Weight status was categorized with the use of body mass index on the basis of measured height and weight (underweight or normal weight, overweight, and obesity). Urine osmolality was determined with the use of freezing-point depression osmometry. Hypohydration was classified according to the following age-dependent formula: ≥831 mOsm/kg - [3.4 × (age - 20 y)]. Total water intake was determined with the use of a 24-h dietary recall and was dichotomized as adequate or low on the basis of the Institute of Medicine's adequate intake recommendations for men and women (men: ≥3.7 or <3.7 L; nonlactating women: ≥2.7 or <2.7 L; lactating women: ≥3.8 or <3.8 L for adequate or low intakes, respectively). We tested interactions and conducted linear and log-binomial regressions. Total water intake (P = 0.002), urine osmolality (P < 0.001), and hypohydration prevalence (P < 0.001) all increased with higher weight status. Interactions between weight status and water intake status were significant in linear (P = 0.005) and log-binomial (P = 0.015) models, which were then stratified. The prevalence ratio of hypohydration between subjects with adequate water intake and those with low water intake was 0.56 (95% CI: 0.43, 0.73) in adults who were underweight or normal weight, 0.67 (95% CI: 0.57, 0.79) in adults who were overweight, and 0.78 (95% CI: 0.70, 0.88) in adults who were obese. On a population level, obesity modifies the association between water intake and hydration status. © 2016 American Society for Nutrition.

Scoring in genetically modified organism proficiency tests based on log-transformed results.

PubMed

Thompson, Michael; Ellison, Stephen L R; Owen, Linda; Mathieson, Kenneth; Powell, Joanne; Key, Pauline; Wood, Roger; Damant, Andrew P

2006-01-01

The study considers data from 2 UK-based proficiency schemes and includes data from a total of 29 rounds and 43 test materials over a period of 3 years. The results from the 2 schemes are similar and reinforce each other. The amplification process used in quantitative polymerase chain reaction determinations predicts a mixture of normal, binomial, and lognormal distributions dominated by the latter 2. As predicted, the study results consistently follow a positively skewed distribution. Log-transformation prior to calculating z-scores is effective in establishing near-symmetric distributions that are sufficiently close to normal to justify interpretation on the basis of the normal distribution.

On Models for Binomial Data with Random Numbers of Trials

PubMed Central

Comulada, W. Scott; Weiss, Robert E.

2010-01-01

Summary A binomial outcome is a count s of the number of successes out of the total number of independent trials n = s + f, where f is a count of the failures. The n are random variables not fixed by design in many studies. Joint modeling of (s, f) can provide additional insight into the science and into the probability π of success that cannot be directly incorporated by the logistic regression model. Observations where n = 0 are excluded from the binomial analysis yet may be important to understanding how π is influenced by covariates. Correlation between s and f may exist and be of direct interest. We propose Bayesian multivariate Poisson models for the bivariate response (s, f), correlated through random effects. We extend our models to the analysis of longitudinal and multivariate longitudinal binomial outcomes. Our methodology was motivated by two disparate examples, one from teratology and one from an HIV tertiary intervention study. PMID:17688514

Risk factors for persistent cervical intraepithelial neoplasia grades 1 and 2: managed by watchful waiting.

PubMed

Ho, Gloria Y F; Einstein, Mark H; Romney, Seymour L; Kadish, Anna S; Abadi, Maria; Mikhail, Magdy; Basu, Jayasri; Thysen, Benjamin; Reimers, Laura; Palan, Prabhudas R; Trim, Shelly; Soroudi, Nafisseh; Burk, Robert D

2011-10-01

: This study examines risk factors for persistent cervical intraepithelial neoplasia (CIN) and examines whether human papillomavirus (HPV) testing predicts persistent lesions. : Women with histologically diagnosed CIN 1 or CIN 2 (n = 206) were followed up every 3 months without treatment. Human papillomavirus genotyping, plasma levels of ascorbic acid, and red blood cell folate levels were obtained. Cervical biopsy at 12 months determined the presence of CIN. Relative risk (RR) was estimated by log-linked binomial regression models. : At 12 months, 70% of CIN 1 versus 54% of CIN 2 lesions spontaneously regressed (p < .001). Levels of folate or ascorbic acid were not associated with persistent CIN at 12 months. Compared with HPV-negative women, those with multiple HPV types (RRs ranged from 1.68 to 2.17 at each follow-up visit) or high-risk types (RRs range = 1.74-2.09) were at increased risk for persistent CIN; women with HPV-16/18 had the highest risk (RRs range = 1.91-2.21). Persistent infection with a high-risk type was also associated with persistent CIN (RRs range = 1.50-2.35). Typing for high-risk HPVs at 6 months only had a sensitivity of 46% in predicting persistence of any lesions at 12 months. : Spontaneous regression of CIN 1 and 2 occurs frequently within 12 months. Human papillomavirus infection is the major risk factor for persistent CIN. However, HPV testing cannot reliably predict persistence of any lesion.

Five-Year Incidence of Visual Impairment in Middle-Aged Iranians: The Shahroud Eye Cohort Study.

PubMed

Hashemi, Hassan; Mehravaran, Shiva; Emamian, Mohammad Hassan; Fotouhi, Akbar

2017-02-01

To study the 5-year incidence of visual impairment and its causes and risk factors, in the middle-aged Iranian sample of the Shahroud Eye Cohort Study (ShECS). Data from subjects who had participated in both phases of the ShECS were used to determine age- and sex-specific incidence rates of visual impairment using the World Health Organization (WHO) definitions for bilateral low vision (visual acuity, VA, >0.5 and ≤1.3 LogMAR in the better eye) and blindness (VA worse than 1.3 LogMAR in the better eye). Risk ratios (RR) and 95% confidence intervals (CIs) were calculated using multivariable log-binomial regression. Of the 5079 ShECS I survivors, 4737 (93.3%) completed the 5-year follow-up. Their mean age at baseline was 50.9 ± 6.2 years, and 58.9% were female. The incidence of visual impairment was 1.12% (95% CI 0.82-1.42%) by presenting VA and 0.19% (95% CI 0.07-0.32%) by best-corrected VA; leading causes of the former were uncorrected refractive error (81.3%) and diabetic retinopathy (15.1%). In the multivariable model, risk factors for incident visual impairment by presenting VA were older age (RR 1.05, p = 0.044), lower education (RR 0.89, p = 0.002), and diabetes (RR 3.74, p < 0.001). This is the first incidence study of visual impairment in a middle-aged Iranian population. Since age is a major risk factor, the number of visually impaired is expected to increase as the population ages, and less treatable causes such as diabetic retinopathy begin to surface. Measures for tackling uncorrected refractive error and enhancing diabetes screening and preventive programs are recommended.

Severity of maternal HIV-1 disease is associated with adverse birth outcomes in Malawian women: a cohort study

PubMed Central

Turner, Abigail Norris; Tabbah, Sammy; Mwapasa, Victor; Rogerson, Stephen J.; Meshnick, Steven R.; Ackerman, William; Kwiek, Jesse J.

2014-01-01

Background Compared to HIV-negative women, HIV-infected women have increased risk of low birth weight (LBW) and preterm delivery (PTD). We assessed whether severity of maternal HIV-1 disease was associated with LBW or PTD. Methods Secondary analysis of The Malaria and HIV in Pregnancy prospective cohort, which enrolled HIV-positive, pregnant Malawian women from 2000–2004. Included participants (n=809) were normotensive, antiretroviral treatment naïve women who delivered a live, singleton infant. Binomial regression models were used to assess the unadjusted and adjusted prevalence ratios (PRs) and 95% confidence intervals (CI) of the effect of severity of HIV-1 disease, defined by viral load and CD4-positive T-cell counts, on prevalence of LBW and PTD. Results In unadjusted analyses, among those with malaria (n=198), there was no association between severity of HIV-1 infection and LBW, while among women without malaria (n=611), we observed a harmful association between both increasing peripheral viral load and LBW (PR: 1.44 per one-log10 increase, 95% CI: 1.12, 1.86) and placental viral load and LBW (PR: 1.24 per one-log10 increase, 95% CI: 1.00, 1.53). We observed a similar association between increasing placental viral load and PTD (PR: 1.33 per one-log10 increase, 95% CI: 1.04, 1.69). These associations persisted in multivariate models adjusted for residence, maternal education, primigravid status, and maternal anemia. Conclusions In malaria-negative women, maternal HIV-1 disease severity was significantly associated with increased prevalence of LBW and PTD. Such an association was not found in the malaria-infected women. PMID:23846560

Severity of maternal HIV-1 disease is associated with adverse birth outcomes in Malawian women: a cohort study.

PubMed

Turner, Abigail Norris; Tabbah, Sammy; Mwapasa, Victor; Rogerson, Stephen J; Meshnick, Steven R; Ackerman, William E; Kwiek, Jesse J

2013-12-01

Compared with HIV-negative women, HIV-infected women have increased risk of low birthweight (LBW) and preterm delivery (PTD). We assessed whether severity of maternal HIV-1 disease was associated with LBW or PTD. Secondary analysis of The Malaria and HIV in Pregnancy prospective cohort, which enrolled HIV-positive, pregnant Malawian women from 2000 to 2004. Included participants (n = 809) were normotensive antiretroviral treatment-naive women who delivered a live singleton infant. Binomial regression models were used to assess the unadjusted and adjusted prevalence ratios (PRs) and 95% confidence intervals (CI) of the effect of severity of HIV-1 disease, defined by viral load and CD4 T-cell counts, on prevalence of LBW and PTD. In unadjusted analyses, among those with malaria (n = 198), there was no association between severity of HIV-1 infection and LBW, whereas among women without malaria (n = 611), we observed a harmful association between both increasing peripheral viral load and LBW (PR: 1.44 per 1-log10 increase, 95% CI: 1.12 to 1.86) and placental viral load and LBW (PR: 1.24 per 1-log10 increase, 95% CI: 1.00 to 1.53). We observed a similar association between increasing placental viral load and PTD (PR: 1.33 per one-log10 increase, 95% CI: 1.04 to 1.69). These associations persisted in multivariate models adjusted for residence, maternal education, primigravid status, and maternal anemia. In malaria-negative women, maternal HIV-1 disease severity was significantly associated with increased prevalence of LBW and PTD. Such an association was not found in the malaria-infected women.

Re-employment, job quality, health and allostatic load biomarkers: prospective evidence from the UK Household Longitudinal Study

PubMed Central

Chandola, Tarani; Zhang, Nan

2018-01-01

Abstract Background There is little evidence on whether becoming re-employed in poor quality work is better for health and well-being than remaining unemployed. We examined associations of job transition with health and chronic stress-related biomarkers among a population-representative cohort of unemployed British adults. Methods A prospective cohort of 1116 eligible participants aged 35 to 75 years, who were unemployed at wave 1 (2009/10) of the UK Household Longitudinal Study, were followed up at waves 2 (2010/11) and 3 (2011/12) for allostatic load biomarkers and self-reported health. Negative binomial and multiple regression models estimated the association between job adversity and these outcomes. Results Compared with adults who remained unemployed, formerly unemployed adults who transitioned into poor quality jobs had higher levels of overall allostatic load (0.51, 0.32–0.71), log HbA1c (0.06, <0.001–0.12), log triglycerides (0.39, 0.22–0.56), log C-reactive protein (0.45, 0.16–0.75), log fibrinogen (0.09, 0.01–0.17) and total cholesterol to high-density lipoprotein (HDL) ratio (1.38, 0.88–1.88). Moreover, physically healthier respondents at wave 1 were more likely to transition into good quality and poor quality jobs after 1 year than those who remained unemployed. Conclusions Formerly unemployed adults who transitioned into poor quality work had greater adverse levels of biomarkers compared with their peers who remained unemployed. The selection of healthier unemployed adults into these poor quality or stressful jobs was unlikely to explain their elevated levels of chronic stress-related biomarkers. Job quality cannot be disregarded from the employment success of the unemployed, and may have important implications for their health and well-being. PMID:29024973

Power law behavior of RR-interval variability in healthy middle-aged persons, patients with recent acute myocardial infarction, and patients with heart transplants

NASA Technical Reports Server (NTRS)

Bigger, J. T. Jr; Steinman, R. C.; Rolnitzky, L. M.; Fleiss, J. L.; Albrecht, P.; Cohen, R. J.

1996-01-01

BACKGROUND. The purposes of the present study were (1) to establish normal values for the regression of log(power) on log(frequency) for, RR-interval fluctuations in healthy middle-aged persons, (2) to determine the effects of myocardial infarction on the regression of log(power) on log(frequency), (3) to determine the effect of cardiac denervation on the regression of log(power) on log(frequency), and (4) to assess the ability of power law regression parameters to predict death after myocardial infarction. METHODS AND RESULTS. We studied three groups: (1) 715 patients with recent myocardial infarction; (2) 274 healthy persons age and sex matched to the infarct sample; and (3) 19 patients with heart transplants. Twenty-four-hour RR-interval power spectra were computed using fast Fourier transforms and log(power) was regressed on log(frequency) between 10(-4) and 10(-2) Hz. There was a power law relation between log(power) and log(frequency). That is, the function described a descending straight line that had a slope of approximately -1 in healthy subjects. For the myocardial infarction group, the regression line for log(power) on log(frequency) was shifted downward and had a steeper negative slope (-1.15). The transplant (denervated) group showed a larger downward shift in the regression line and a much steeper negative slope (-2.08). The correlation between traditional power spectral bands and slope was weak, and that with log(power) at 10(-4) Hz was only moderate. Slope and log(power) at 10(-4) Hz were used to predict mortality and were compared with the predictive value of traditional power spectral bands. Slope and log(power) at 10(-4) Hz were excellent predictors of all-cause mortality or arrhythmic death. To optimize the prediction of death, we calculated a log(power) intercept that was uncorrelated with the slope of the power law regression line. We found that the combination of slope and zero-correlation log(power) was an outstanding predictor, with a relative risk of > 10, and was better than any combination of the traditional power spectral bands. The combination of slope and log(power) at 10(-4) Hz also was an excellent predictor of death after myocardial infarction. CONCLUSIONS. Myocardial infarction or denervation of the heart causes a steeper slope and decreased height of the power law regression relation between log(power) and log(frequency) of RR-interval fluctuations. Individually and, especially, combined, the power law regression parameters are excellent predictors of death of any cause or arrhythmic death and predict these outcomes better than the traditional power spectral bands.

Variability in results from negative binomial models for Lyme disease measured at different spatial scales.

PubMed

Tran, Phoebe; Waller, Lance

2015-01-01

Lyme disease has been the subject of many studies due to increasing incidence rates year after year and the severe complications that can arise in later stages of the disease. Negative binomial models have been used to model Lyme disease in the past with some success. However, there has been little focus on the reliability and consistency of these models when they are used to study Lyme disease at multiple spatial scales. This study seeks to explore how sensitive/consistent negative binomial models are when they are used to study Lyme disease at different spatial scales (at the regional and sub-regional levels). The study area includes the thirteen states in the Northeastern United States with the highest Lyme disease incidence during the 2002-2006 period. Lyme disease incidence at county level for the period of 2002-2006 was linked with several previously identified key landscape and climatic variables in a negative binomial regression model for the Northeastern region and two smaller sub-regions (the New England sub-region and the Mid-Atlantic sub-region). This study found that negative binomial models, indeed, were sensitive/inconsistent when used at different spatial scales. We discuss various plausible explanations for such behavior of negative binomial models. Further investigation of the inconsistency and sensitivity of negative binomial models when used at different spatial scales is important for not only future Lyme disease studies and Lyme disease risk assessment/management but any study that requires use of this model type in a spatial context. Copyright © 2014 Elsevier Inc. All rights reserved.

Occupational injury among hospital patient-care workers: what is the association with workplace verbal abuse?

PubMed

Sabbath, Erika L; Hurtado, David A; Okechukwu, Cassandra A; Tamers, Sara L; Nelson, Candace; Kim, Seung-Sup; Wagner, Gregory; Sorenson, Glorian

2014-02-01

To test the association between workplace abuse exposure and injury risk among hospital workers. We hypothesized that exposed workers would have higher injury rates than unexposed workers. Survey of direct-care workers (n = 1,497) in two hospitals. Exposure to workplace abuse was assessed through self-report; occupational injury reports were extracted from employee records. We tested associations between non-physical workplace violence and injury using log-binomial regression and multilevel modeling. Adjusted prevalence ratio (PR) for injury associated with being yelled at was 1.52 (95% CI 1.19, 1.95); for experiencing hostile/offensive gestures 1.43 (1.11, 1.82); and for being sworn at 1.41 (1.09, 1.81). In analyses by injury subtypes, musculoskeletal injuries were more strongly associated with abuse than were acute traumatic injuries. Associations operated on group and individual levels and were most consistently associated with abuse perpetrated by patients. Exposure to workplace abuse may be a risk factor for injuries among hospital workers. © 2013 Wiley Periodicals, Inc.

Increased symptom reporting persists in 1990-1991 Gulf War veterans 20 years post deployment.

PubMed

Gwini, Stella M; Forbes, Andrew B; Kelsall, Helen L; Ikin, Jillian F; Sim, Malcolm R

2015-12-01

Following the 1990-1991 Gulf War, Gulf War veterans (veterans) reported health symptoms more commonly than non-deployed groups. This article examines symptom persistence, incidence and prevalence 20 years on. In 2000-2003 and 2011-2012, a 63-item symptom checklist was administered to 697 veterans and 659 comparison group. Symptomatology was compared using log-binomial regression. Both veterans and comparison group reported significantly increased prevalence (3-52%) over time in more than half the symptoms, with a similar overall rate of increase. Half the symptoms had higher incidence (risk-ratios ranged 1.43-1.50) and a quarter were more persistent (risk-ratios ranged 1.12-1.20) in veterans than the comparison group. Symptomatology increased in both groups over time, but persisted to a similar extent and had higher incidence among veterans than the comparison group. The gap in symptom prevalence between the two groups remained unchanged. These findings suggest enduring health consequences of Gulf War service. © 2015 Commonwealth of Australia. American Journal of Industrial Medicine © 2015 Wiley Periodicals, Inc.

Trends and correlates of child passenger restraint use in 6 Northwest tribes: the Native Children Always Ride Safe (Native CARS) project.

PubMed

Lapidus, Jodi A; Smith, Nicole Holdaway; Lutz, Tam; Ebel, Beth E

2013-02-01

We compared proportions of children properly restrained in vehicles in 6 Northwest American Indian tribes in 2003 and 2009, and evaluated risks for improper restraint. During spring 2009 we conducted a vehicle observation survey in Oregon, Washington, and Idaho tribal communities. We estimated the proportions of children riding properly restrained and evaluated correlates of improper restraint via log-binomial regression models for clustered data. We observed 1853 children aged 12 years and younger in 1207 vehicles; 49% rode properly restrained. More children aged 8 years and younger rode properly restrained in 2009 than 2003 (51% vs 29%; P < .001). Older booster seat-eligible children were least likely to ride properly restrained in 2009 (25%). American Indian children were more likely to ride improperly restrained than nonnative children in the same communities. Other risk factors included riding with an unrestrained or nonparent driver, riding where child passenger restraint laws were weaker than national guidelines, and taking a short trip. Although proper restraint has increased, it remains low. Tribe-initiated interventions to improve child passenger restraint use are under way.

Electronic fetal heart rate monitoring and its relationship to neonatal and infant mortality in the United States.

PubMed

Chen, Han-Yang; Chauhan, Suneet P; Ananth, Cande V; Vintzileos, Anthony M; Abuhamad, Alfred Z

2011-06-01

To examine the association between electronic fetal heart rate monitoring and neonatal and infant mortality, as well as neonatal morbidity. We used the United States 2004 linked birth and infant death data. Multivariable log-binomial regression models were fitted to estimate risk ratio for association between electronic fetal heart rate monitoring and mortality, while adjusting for potential confounders. In 2004, 89% of singleton pregnancies had electronic fetal heart rate monitoring. Electronic fetal heart rate monitoring was associated with significantly lower infant mortality (adjusted relative risk, 0.75); this was mainly driven by the lower risk of early neonatal mortality (adjusted relative risk, 0.50). In low-risk pregnancies, electronic fetal heart rate monitoring was associated with decreased risk for Apgar scores <4 at 5 minutes (relative risk, 0.54); in high-risk pregnancies, with decreased risk of neonatal seizures (relative risk, 0.65). In the United States, the use of electronic fetal heart rate monitoring was associated with a substantial decrease in early neonatal mortality and morbidity that lowered infant mortality. Copyright © 2011 Mosby, Inc. All rights reserved.

Selecting a distributional assumption for modelling relative densities of benthic macroinvertebrates

USGS Publications Warehouse

Gray, B.R.

2005-01-01

The selection of a distributional assumption suitable for modelling macroinvertebrate density data is typically challenging. Macroinvertebrate data often exhibit substantially larger variances than expected under a standard count assumption, that of the Poisson distribution. Such overdispersion may derive from multiple sources, including heterogeneity of habitat (historically and spatially), differing life histories for organisms collected within a single collection in space and time, and autocorrelation. Taken to extreme, heterogeneity of habitat may be argued to explain the frequent large proportions of zero observations in macroinvertebrate data. Sampling locations may consist of habitats defined qualitatively as either suitable or unsuitable. The former category may yield random or stochastic zeroes and the latter structural zeroes. Heterogeneity among counts may be accommodated by treating the count mean itself as a random variable, while extra zeroes may be accommodated using zero-modified count assumptions, including zero-inflated and two-stage (or hurdle) approaches. These and linear assumptions (following log- and square root-transformations) were evaluated using 9 years of mayfly density data from a 52 km, ninth-order reach of the Upper Mississippi River (n = 959). The data exhibited substantial overdispersion relative to that expected under a Poisson assumption (i.e. variance:mean ratio = 23 ??? 1), and 43% of the sampling locations yielded zero mayflies. Based on the Akaike Information Criterion (AIC), count models were improved most by treating the count mean as a random variable (via a Poisson-gamma distributional assumption) and secondarily by zero modification (i.e. improvements in AIC values = 9184 units and 47-48 units, respectively). Zeroes were underestimated by the Poisson, log-transform and square root-transform models, slightly by the standard negative binomial model but not by the zero-modified models (61%, 24%, 32%, 7%, and 0%, respectively). However, the zero-modified Poisson models underestimated small counts (1 ??? y ??? 4) and overestimated intermediate counts (7 ??? y ??? 23). Counts greater than zero were estimated well by zero-modified negative binomial models, while counts greater than one were also estimated well by the standard negative binomial model. Based on AIC and percent zero estimation criteria, the two-stage and zero-inflated models performed similarly. The above inferences were largely confirmed when the models were used to predict values from a separate, evaluation data set (n = 110). An exception was that, using the evaluation data set, the standard negative binomial model appeared superior to its zero-modified counterparts using the AIC (but not percent zero criteria). This and other evidence suggest that a negative binomial distributional assumption should be routinely considered when modelling benthic macroinvertebrate data from low flow environments. Whether negative binomial models should themselves be routinely examined for extra zeroes requires, from a statistical perspective, more investigation. However, this question may best be answered by ecological arguments that may be specific to the sampled species and locations. ?? 2004 Elsevier B.V. All rights reserved.

Marital status and survival of patients with oral cavity squamous cell carcinoma: a population-based study.

PubMed

Shi, Xiao; Zhang, Ting-Ting; Hu, Wei-Ping; Ji, Qing-Hai

2017-04-25

The relationship between marital status and oral cavity squamous cell carcinoma (OCSCC) survival has not been explored. The objective of our study was to evaluate the impact of marital status on OCSCC survival and investigate the potential mechanisms. Married patients had better 5-year cancer-specific survival (CSS) (66.7% vs 54.9%) and 5-year overall survival (OS) (56.0% vs 41.1%). In multivariate Cox regression models, unmarried patients also showed higher mortality risk for both CSS (Hazard Ratio [HR]: 1.260, 95% confidence interval (CI): 1.187-1.339, P < 0.001) and OS (HR: 1.328, 95% CI: 1.266-1.392, P < 0.001). Multivariate logistic regression showed married patients were more likely to be diagnosed at earlier stage (P < 0.001) and receive surgery (P < 0.001). Married patients still demonstrated better prognosis in the 1:1 matched group analysis (CSS: 62.9% vs 60.8%, OS: 52.3% vs 46.5%). 11022 eligible OCSCC patients were identified from Surveillance, Epidemiology, and End Results (SEER) database, including 5902 married and 5120 unmarried individuals. Kaplan-Meier analysis, Log-rank test and Cox proportional hazards regression model were used to analyze survival and mortality risk. Influence of marital status on stage, age at diagnosis and selection of treatment was determined by binomial and multinomial logistic regression. Propensity score matching method was adopted to perform a 1:1 matched cohort. Marriage has an independently protective effect on OCSCC survival. Earlier diagnosis and more sufficient treatment are possible explanations. Besides, even after 1:1 matching, survival advantage of married group still exists, indicating that spousal support from other aspects may also play an important role.

Marital status and survival of patients with oral cavity squamous cell carcinoma: a population-based study

PubMed Central

Shi, Xiao; Zhang, Ting-ting; Hu, Wei-ping; Ji, Qing-hai

2017-01-01

Background The relationship between marital status and oral cavity squamous cell carcinoma (OCSCC) survival has not been explored. The objective of our study was to evaluate the impact of marital status on OCSCC survival and investigate the potential mechanisms. Results Married patients had better 5-year cancer-specific survival (CSS) (66.7% vs 54.9%) and 5-year overall survival (OS) (56.0% vs 41.1%). In multivariate Cox regression models, unmarried patients also showed higher mortality risk for both CSS (Hazard Ratio [HR]: 1.260, 95% confidence interval (CI): 1.187–1.339, P < 0.001) and OS (HR: 1.328, 95% CI: 1.266–1.392, P < 0.001). Multivariate logistic regression showed married patients were more likely to be diagnosed at earlier stage (P < 0.001) and receive surgery (P < 0.001). Married patients still demonstrated better prognosis in the 1:1 matched group analysis (CSS: 62.9% vs 60.8%, OS: 52.3% vs 46.5%). Materials and Methods 11022 eligible OCSCC patients were identified from Surveillance, Epidemiology, and End Results (SEER) database, including 5902 married and 5120 unmarried individuals. Kaplan-Meier analysis, Log-rank test and Cox proportional hazards regression model were used to analyze survival and mortality risk. Influence of marital status on stage, age at diagnosis and selection of treatment was determined by binomial and multinomial logistic regression. Propensity score matching method was adopted to perform a 1:1 matched cohort. Conclusions Marriage has an independently protective effect on OCSCC survival. Earlier diagnosis and more sufficient treatment are possible explanations. Besides, even after 1:1 matching, survival advantage of married group still exists, indicating that spousal support from other aspects may also play an important role. PMID:28415710

Establishing endangered species recovery criteria using predictive simulation modeling

USGS Publications Warehouse

McGowan, Conor P.; Catlin, Daniel H.; Shaffer, Terry L.; Gratto-Trevor, Cheri L.; Aron, Carol

2014-01-01

Listing a species under the Endangered Species Act (ESA) and developing a recovery plan requires U.S. Fish and Wildlife Service to establish specific and measurable criteria for delisting. Generally, species are listed because they face (or are perceived to face) elevated risk of extinction due to issues such as habitat loss, invasive species, or other factors. Recovery plans identify recovery criteria that reduce extinction risk to an acceptable level. It logically follows that the recovery criteria, the defined conditions for removing a species from ESA protections, need to be closely related to extinction risk. Extinction probability is a population parameter estimated with a model that uses current demographic information to project the population into the future over a number of replicates, calculating the proportion of replicated populations that go extinct. We simulated extinction probabilities of piping plovers in the Great Plains and estimated the relationship between extinction probability and various demographic parameters. We tested the fit of regression models linking initial abundance, productivity, or population growth rate to extinction risk, and then, using the regression parameter estimates, determined the conditions required to reduce extinction probability to some pre-defined acceptable threshold. Binomial regression models with mean population growth rate and the natural log of initial abundance were the best predictors of extinction probability 50 years into the future. For example, based on our regression models, an initial abundance of approximately 2400 females with an expected mean population growth rate of 1.0 will limit extinction risk for piping plovers in the Great Plains to less than 0.048. Our method provides a straightforward way of developing specific and measurable recovery criteria linked directly to the core issue of extinction risk. Published by Elsevier Ltd.

The effect of cotrimoxazole prophylactic treatment on malaria, birth outcomes, and postpartum CD4 count in HIV-infected women.

PubMed

Dow, Anna; Kayira, Dumbani; Hudgens, Michael G; Van Rie, Annelies; King, Caroline C; Ellington, Sascha; Chome, Nelecy; Kourtis, Athena; Turner, Abigail Norris; Kacheche, Zebrone; Jamieson, Denise J; Chasela, Charles; van der Horst, Charles

2013-01-01

Limited data exist on cotrimoxazole prophylactic treatment (CPT) in pregnant women, including protection against malaria versus standard intermittent preventive therapy with sulfadoxine-pyrimethamine (IPTp). Using observational data we examined the effect of CPT in HIV-infected pregnant women on malaria during pregnancy, low birth weight and preterm birth using proportional hazards, logistic, and log binomial regression, respectively. We used linear regression to assess effect of CPT on CD4 count. Data from 468 CPT-exposed and 768 CPT-unexposed women were analyzed. CPT was associated with protection against malaria versus IPTp (hazard ratio: 0.35, 95% Confidence Interval (CI): 0.20, 0.60). After adjustment for time period this effect was not statistically significant (adjusted hazard ratio: 0.66, 95% CI: 0.28, 1.52). Among women receiving and not receiving CPT, rates of low birth weight (7.1% versus 7.6%) and preterm birth (23.5% versus 23.6%) were similar. CPT was associated with lower CD4 counts 24 weeks postpartum in women receiving (-77.6 cells/ μ L, 95% CI: -125.2, -30.1) and not receiving antiretrovirals (-33.7 cells/ μ L, 95% CI: -58.6, -8.8). Compared to IPTp, CPT provided comparable protection against malaria in HIV-infected pregnant women and against preterm birth or low birth weight. Possible implications of CPT-associated lower CD4 postpartum warrant further examination.

The analysis of incontinence episodes and other count data in patients with overactive bladder by Poisson and negative binomial regression.

PubMed

Martina, R; Kay, R; van Maanen, R; Ridder, A

2015-01-01

Clinical studies in overactive bladder have traditionally used analysis of covariance or nonparametric methods to analyse the number of incontinence episodes and other count data. It is known that if the underlying distributional assumptions of a particular parametric method do not hold, an alternative parametric method may be more efficient than a nonparametric one, which makes no assumptions regarding the underlying distribution of the data. Therefore, there are advantages in using methods based on the Poisson distribution or extensions of that method, which incorporate specific features that provide a modelling framework for count data. One challenge with count data is overdispersion, but methods are available that can account for this through the introduction of random effect terms in the modelling, and it is this modelling framework that leads to the negative binomial distribution. These models can also provide clinicians with a clearer and more appropriate interpretation of treatment effects in terms of rate ratios. In this paper, the previously used parametric and non-parametric approaches are contrasted with those based on Poisson regression and various extensions in trials evaluating solifenacin and mirabegron in patients with overactive bladder. In these applications, negative binomial models are seen to fit the data well. Copyright © 2014 John Wiley & Sons, Ltd.

Interrelationships Between Receiver/Relative Operating Characteristics Display, Binomial, Logit, and Bayes' Rule Probability of Detection Methodologies

NASA Technical Reports Server (NTRS)

Generazio, Edward R.

2014-01-01

Unknown risks are introduced into failure critical systems when probability of detection (POD) capabilities are accepted without a complete understanding of the statistical method applied and the interpretation of the statistical results. The presence of this risk in the nondestructive evaluation (NDE) community is revealed in common statements about POD. These statements are often interpreted in a variety of ways and therefore, the very existence of the statements identifies the need for a more comprehensive understanding of POD methodologies. Statistical methodologies have data requirements to be met, procedures to be followed, and requirements for validation or demonstration of adequacy of the POD estimates. Risks are further enhanced due to the wide range of statistical methodologies used for determining the POD capability. Receiver/Relative Operating Characteristics (ROC) Display, simple binomial, logistic regression, and Bayes' rule POD methodologies are widely used in determining POD capability. This work focuses on Hit-Miss data to reveal the framework of the interrelationships between Receiver/Relative Operating Characteristics Display, simple binomial, logistic regression, and Bayes' Rule methodologies as they are applied to POD. Knowledge of these interrelationships leads to an intuitive and global understanding of the statistical data, procedural and validation requirements for establishing credible POD estimates.

Introductory Statistics in the Garden

ERIC Educational Resources Information Center

Wagaman, John C.

2017-01-01

This article describes four semesters of introductory statistics courses that incorporate service learning and gardening into the curriculum with applications of the binomial distribution, least squares regression and hypothesis testing. The activities span multiple semesters and are iterative in nature.

Simulation of flight maneuver-load distributions by utilizing stationary, non-Gaussian random load histories

NASA Technical Reports Server (NTRS)

Leybold, H. A.

1971-01-01

Random numbers were generated with the aid of a digital computer and transformed such that the probability density function of a discrete random load history composed of these random numbers had one of the following non-Gaussian distributions: Poisson, binomial, log-normal, Weibull, and exponential. The resulting random load histories were analyzed to determine their peak statistics and were compared with cumulative peak maneuver-load distributions for fighter and transport aircraft in flight.

Mental health status and healthcare utilization among community dwelling older adults.

PubMed

Adepoju, Omolola; Lin, Szu-Hsuan; Mileski, Michael; Kruse, Clemens Scott; Mask, Andrew

2018-04-27

Shifts in mental health utilization patterns are necessary to allow for meaningful access to care for vulnerable populations. There have been long standing issues in how mental health is provided, which has caused problems in that care being efficacious for those seeking it. To assess the relationship between mental health status and healthcare utilization among adults ≥65 years. A negative binomial regression model was used to assess the relationship between mental health status and healthcare utilization related to office-based physician visits, while a two-part model, consisting of logistic regression and negative binomial regression, was used to separately model emergency visits and inpatient services. The receipt of care in office-based settings were marginally higher for subjects with mental health difficulties. Both probabilities and counts of inpatient hospitalizations were similar across mental health categories. The count of ER visits was similar across mental health categories; however, the probability of having an emergency department visit was marginally higher for older adults who reported mental health difficulties in 2012. These findings are encouraging and lend promise to the recent initiatives on addressing gaps in mental healthcare services.

An examination of sources of sensitivity of consumer surplus estimates in travel cost models.

PubMed

Blaine, Thomas W; Lichtkoppler, Frank R; Bader, Timothy J; Hartman, Travis J; Lucente, Joseph E

2015-03-15

We examine sensitivity of estimates of recreation demand using the Travel Cost Method (TCM) to four factors. Three of the four have been routinely and widely discussed in the TCM literature: a) Poisson verses negative binomial regression; b) application of Englin correction to account for endogenous stratification; c) truncation of the data set to eliminate outliers. A fourth issue we address has not been widely modeled: the potential effect on recreation demand of the interaction between income and travel cost. We provide a straightforward comparison of all four factors, analyzing the impact of each on regression parameters and consumer surplus estimates. Truncation has a modest effect on estimates obtained from the Poisson models but a radical effect on the estimates obtained by way of the negative binomial. Inclusion of an income-travel cost interaction term generally produces a more conservative but not a statistically significantly different estimate of consumer surplus in both Poisson and negative binomial models. It also generates broader confidence intervals. Application of truncation, the Englin correction and the income-travel cost interaction produced the most conservative estimates of consumer surplus and eliminated the statistical difference between the Poisson and the negative binomial. Use of the income-travel cost interaction term reveals that for visitors who face relatively low travel costs, the relationship between income and travel demand is negative, while it is positive for those who face high travel costs. This provides an explanation of the ambiguities on the findings regarding the role of income widely observed in the TCM literature. Our results suggest that policies that reduce access to publicly owned resources inordinately impact local low income recreationists and are contrary to environmental justice. Copyright © 2014 Elsevier Ltd. All rights reserved.

Health care seeking patterns and determinants of out-of-pocket expenditure for Malaria for the children under-five in Uganda

PubMed Central

2013-01-01

Background The objectives of this study were to assess the patterns of treatment seeking behaviour for children under five with malaria; and to examine the statistical relationship between out-of-pocket expenditure (OOP) on malaria treatment for under-fives and source of treatment, place of residence, education and wealth characteristics of Uganda households. OOP expenditure on health care is now a development concern due to its negative effect on households’ ability to finance consumption of other basic needs. Methods The 2009 Uganda Malaria Indicator Survey was the source of data on treatment seeking behaviour for under-five children with malaria, and patterns and levels of OOP expenditure for malaria treatment. Binomial logit and Log-lin regression models were estimated. In logit model the dependent variable was a dummy (1=incurred some OOP, 0=none incurred) and independent variables were wealth quintiles, rural versus urban, place of treatment, education level, sub-region, and normal duty disruption. The dependent variable in Log-lin model was natural logarithm of OOP and the independent variables were the same as mentioned above. Results Five key descriptive analysis findings emerge. First, malaria is quite prevalent at 44.7% among children below the age of five. Second, a significant proportion seeks treatment (81.8%). Third, private providers are the preferred option for the under-fives for the treatment of malaria. Fourth, the majority pay about 70.9% for either consultation, medicines, transport or hospitalization but the biggest percent of those who pay, do so for medicines (54.0%). Fifth, hospitalization is the most expensive at an average expenditure of US$7.6 per child, even though only 2.9% of those that seek treatment are hospitalized. The binomial logit model slope coefficients for the variables richest wealth quintile, Private facility as first source of treatment, and sub-regions Central 2, East central, Mid-eastern, Mid-western, and Normal duties disrupted were positive and statistically significant at 99% level of confidence. On the other hand, the Log-lin model slope coefficients for Traditional healer, Sought treatment from one source, Primary educational level, North East, Mid Northern and West Nile variables had a negative sign and were statistically significant at 95% level of confidence. Conclusion The fact that OOP expenditure is still prevalent and private provider is the preferred choice, increasing public provision may not be the sole answer. Plans to improve malaria treatment should explicitly incorporate efforts to protect households from high OOP expenditures. This calls for provision of subsidies to enable the private sector to reduce prices, regulation of prices of malaria medicines, and reduction/removal of import duties on such medicines. PMID:23721217

Measurement error and outcome distributions: Methodological issues in regression analyses of behavioral coding data.

PubMed

Holsclaw, Tracy; Hallgren, Kevin A; Steyvers, Mark; Smyth, Padhraic; Atkins, David C

2015-12-01

Behavioral coding is increasingly used for studying mechanisms of change in psychosocial treatments for substance use disorders (SUDs). However, behavioral coding data typically include features that can be problematic in regression analyses, including measurement error in independent variables, non normal distributions of count outcome variables, and conflation of predictor and outcome variables with third variables, such as session length. Methodological research in econometrics has shown that these issues can lead to biased parameter estimates, inaccurate standard errors, and increased Type I and Type II error rates, yet these statistical issues are not widely known within SUD treatment research, or more generally, within psychotherapy coding research. Using minimally technical language intended for a broad audience of SUD treatment researchers, the present paper illustrates the nature in which these data issues are problematic. We draw on real-world data and simulation-based examples to illustrate how these data features can bias estimation of parameters and interpretation of models. A weighted negative binomial regression is introduced as an alternative to ordinary linear regression that appropriately addresses the data characteristics common to SUD treatment behavioral coding data. We conclude by demonstrating how to use and interpret these models with data from a study of motivational interviewing. SPSS and R syntax for weighted negative binomial regression models is included in online supplemental materials. (c) 2016 APA, all rights reserved).

Measurement error and outcome distributions: Methodological issues in regression analyses of behavioral coding data

PubMed Central

Holsclaw, Tracy; Hallgren, Kevin A.; Steyvers, Mark; Smyth, Padhraic; Atkins, David C.

2015-01-01

Behavioral coding is increasingly used for studying mechanisms of change in psychosocial treatments for substance use disorders (SUDs). However, behavioral coding data typically include features that can be problematic in regression analyses, including measurement error in independent variables, non-normal distributions of count outcome variables, and conflation of predictor and outcome variables with third variables, such as session length. Methodological research in econometrics has shown that these issues can lead to biased parameter estimates, inaccurate standard errors, and increased type-I and type-II error rates, yet these statistical issues are not widely known within SUD treatment research, or more generally, within psychotherapy coding research. Using minimally-technical language intended for a broad audience of SUD treatment researchers, the present paper illustrates the nature in which these data issues are problematic. We draw on real-world data and simulation-based examples to illustrate how these data features can bias estimation of parameters and interpretation of models. A weighted negative binomial regression is introduced as an alternative to ordinary linear regression that appropriately addresses the data characteristics common to SUD treatment behavioral coding data. We conclude by demonstrating how to use and interpret these models with data from a study of motivational interviewing. SPSS and R syntax for weighted negative binomial regression models is included in supplementary materials. PMID:26098126

Logistic quantile regression provides improved estimates for bounded avian counts: a case study of California Spotted Owl fledgling production

Treesearch

Brian S. Cade; Barry R. Noon; Rick D. Scherer; John J. Keane

2017-01-01

Counts of avian fledglings, nestlings, or clutch size that are bounded below by zero and above by some small integer form a discrete random variable distribution that is not approximated well by conventional parametric count distributions such as the Poisson or negative binomial. We developed a logistic quantile regression model to provide estimates of the empirical...

Goodness-of-fit tests and model diagnostics for negative binomial regression of RNA sequencing data.

PubMed

Mi, Gu; Di, Yanming; Schafer, Daniel W

2015-01-01

This work is about assessing model adequacy for negative binomial (NB) regression, particularly (1) assessing the adequacy of the NB assumption, and (2) assessing the appropriateness of models for NB dispersion parameters. Tools for the first are appropriate for NB regression generally; those for the second are primarily intended for RNA sequencing (RNA-Seq) data analysis. The typically small number of biological samples and large number of genes in RNA-Seq analysis motivate us to address the trade-offs between robustness and statistical power using NB regression models. One widely-used power-saving strategy, for example, is to assume some commonalities of NB dispersion parameters across genes via simple models relating them to mean expression rates, and many such models have been proposed. As RNA-Seq analysis is becoming ever more popular, it is appropriate to make more thorough investigations into power and robustness of the resulting methods, and into practical tools for model assessment. In this article, we propose simulation-based statistical tests and diagnostic graphics to address model adequacy. We provide simulated and real data examples to illustrate that our proposed methods are effective for detecting the misspecification of the NB mean-variance relationship as well as judging the adequacy of fit of several NB dispersion models.

Understanding logistic regression analysis.

PubMed

Sperandei, Sandro

2014-01-01

Logistic regression is used to obtain odds ratio in the presence of more than one explanatory variable. The procedure is quite similar to multiple linear regression, with the exception that the response variable is binomial. The result is the impact of each variable on the odds ratio of the observed event of interest. The main advantage is to avoid confounding effects by analyzing the association of all variables together. In this article, we explain the logistic regression procedure using examples to make it as simple as possible. After definition of the technique, the basic interpretation of the results is highlighted and then some special issues are discussed.

Trends and Correlates of Child Passenger Restraint Use in 6 Northwest Tribes: The Native Children Always Ride Safe (Native CARS) Project

PubMed Central

Smith, Nicole Holdaway; Lutz, Tam; Ebel, Beth E.

2013-01-01

Objectives. We compared proportions of children properly restrained in vehicles in 6 Northwest American Indian tribes in 2003 and 2009, and evaluated risks for improper restraint. Methods. During spring 2009 we conducted a vehicle observation survey in Oregon, Washington, and Idaho tribal communities. We estimated the proportions of children riding properly restrained and evaluated correlates of improper restraint via log-binomial regression models for clustered data. Results. We observed 1853 children aged 12 years and younger in 1207 vehicles; 49% rode properly restrained. More children aged 8 years and younger rode properly restrained in 2009 than 2003 (51% vs 29%; P < .001). Older booster seat–eligible children were least likely to ride properly restrained in 2009 (25%). American Indian children were more likely to ride improperly restrained than nonnative children in the same communities. Other risk factors included riding with an unrestrained or nonparent driver, riding where child passenger restraint laws were weaker than national guidelines, and taking a short trip. Conclusions. Although proper restraint has increased, it remains low. Tribe-initiated interventions to improve child passenger restraint use are under way. PMID:23237177

Marginalized zero-altered models for longitudinal count data.

PubMed

Tabb, Loni Philip; Tchetgen, Eric J Tchetgen; Wellenius, Greg A; Coull, Brent A

2016-10-01

Count data often exhibit more zeros than predicted by common count distributions like the Poisson or negative binomial. In recent years, there has been considerable interest in methods for analyzing zero-inflated count data in longitudinal or other correlated data settings. A common approach has been to extend zero-inflated Poisson models to include random effects that account for correlation among observations. However, these models have been shown to have a few drawbacks, including interpretability of regression coefficients and numerical instability of fitting algorithms even when the data arise from the assumed model. To address these issues, we propose a model that parameterizes the marginal associations between the count outcome and the covariates as easily interpretable log relative rates, while including random effects to account for correlation among observations. One of the main advantages of this marginal model is that it allows a basis upon which we can directly compare the performance of standard methods that ignore zero inflation with that of a method that explicitly takes zero inflation into account. We present simulations of these various model formulations in terms of bias and variance estimation. Finally, we apply the proposed approach to analyze toxicological data of the effect of emissions on cardiac arrhythmias.

Marginalized zero-altered models for longitudinal count data

PubMed Central

Tabb, Loni Philip; Tchetgen, Eric J. Tchetgen; Wellenius, Greg A.; Coull, Brent A.

2015-01-01

Count data often exhibit more zeros than predicted by common count distributions like the Poisson or negative binomial. In recent years, there has been considerable interest in methods for analyzing zero-inflated count data in longitudinal or other correlated data settings. A common approach has been to extend zero-inflated Poisson models to include random effects that account for correlation among observations. However, these models have been shown to have a few drawbacks, including interpretability of regression coefficients and numerical instability of fitting algorithms even when the data arise from the assumed model. To address these issues, we propose a model that parameterizes the marginal associations between the count outcome and the covariates as easily interpretable log relative rates, while including random effects to account for correlation among observations. One of the main advantages of this marginal model is that it allows a basis upon which we can directly compare the performance of standard methods that ignore zero inflation with that of a method that explicitly takes zero inflation into account. We present simulations of these various model formulations in terms of bias and variance estimation. Finally, we apply the proposed approach to analyze toxicological data of the effect of emissions on cardiac arrhythmias. PMID:27867423

Maternal sleep and small for gestational age infants in the Japan Environment and Children's Study: a cohort study.

PubMed

Morokuma, Seiichi; Shimokawa, Mototsugu; Kato, Kiyoko; Sanefuji, Masafumi; Shibata, Eiji; Tsuji, Mayumi; Senju, Ayako; Kawamoto, Toshihiro; Kusuhara, Koichi

2017-08-11

Small for gestational age infants have an increased risk of immediate complications, short-term morbidity and mortality, and long-term neurologic and metabolic disorders in adulthood. Previous research has shown that reduced sleep duration is a risk factor for SGA birth. However, only a few studies have evaluated maternal sleep as a risk factor for SGA birth. In the present study, we investigated the relationship between the amount and quality of mothers' sleep and infants' birth weight. This cohort study (n = 8631) used data from the Japan Environment and Children's Study, an ongoing cohort study that began in January 2011. Data on sleep status (sleep duration and one indicator of sleep quality) and potential confounding factors were recorded. A log-binomial regression model was used to estimate the risk of small for gestational age birth, and the results were expressed as risk ratios and their respective 95% confidence interval. No significant results were observed for sleep duration or tiredness upon waking. Neither the amount nor the quality of mothers' sleep was associated with the risk of small for gestational age birth.

Work and family stress is associated with menstrual disorders but not with fibrocystic changes: cross-sectional findings in Chinese working women.

PubMed

Zhou, Mei; Wege, Natalia; Gu, Huakang; Shang, Li; Li, Jian; Siegrist, Johannes

2010-01-01

To explore the separate and combined effects of work and family stress on menstrual disorders and fibrocystic changes in Chinese working women. Data were obtained from a cross-sectional study of 1,642 female railway workers. The Effort-Reward Imbalance Questionnaire and Family Stress Scale were used to measure work stress and family stress, respectively; the menstrual and breast conditions were evaluated by gynecologic interview and a medical examination. Multivariate log-binomial regression was performed to analyze the associations. Menstrual disorders were found in 59.3% of female workers, and 54.8% had fibrocystic changes. The risk of menstrual disorders was significantly elevated with respect to work and family stress. The highest risk was found in the group with combined exposure to both work and family stress (RR with 95% CI 1.33 (1.18-1.49)). No significant association between stress and fibrocystic changes was observed. Menstrual disorders were associated with stress from work and family life, but not fibrocystic changes, in working women. Tailored intervention measures reducing the burden of stressful psychosocial work and family environment are needed to improve women's reproductive well-being.

Effect of asthma and PTSD on persistence and onset of gastroesophageal reflux symptoms among adults exposed to the September 11, 2001, terrorist attacks.

PubMed

Li, Jiehui; Brackbill, Robert M; Jordan, Hannah T; Cone, James E; Farfel, Mark R; Stellman, Steven D

2016-09-01

Little is known about the direction of causality among asthma, posttraumatic stress disorder (PTSD), and onset of gastroesophageal reflux symptoms (GERS) after exposure to the 9/11/2001 World Trade Center (WTC) disaster. Using data from the WTC Health Registry, we investigated the effects of early diagnosed post-9/11 asthma and PTSD on the late onset and persistence of GERS using log-binomial regression, and examined whether PTSD mediated the asthma-GERS association using structural equation modeling. Of 29,406 enrollees, 23% reported GERS at follow-up in 2011-2012. Early post-9/11 asthma and PTSD were each independently associated with both the persistence of GERS that was present at baseline and the development of GERS in persons without a prior history. PTSD mediated the association between early post-9/11 asthma and late-onset GERS. Clinicians should assess patients with post-9/11 GERS for comorbid asthma and PTSD, and plan medical care for these conditions in an integrated fashion. Am. J. Ind. Med. 59:805-814, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Integrating HIV Surveillance and Field Services: Data Quality and Care Continuum in King County, Washington, 2010-2015.

PubMed

Hood, Julia E; Katz, David A; Bennett, Amy B; Buskin, Susan E; Dombrowski, Julia C; Hawes, Stephen E; Golden, Matthew R

2017-12-01

To assess how integration of HIV surveillance and field services might influence surveillance data and linkage to care metrics. We used HIV surveillance and field services data from King County, Washington, to assess potential impact of misclassification of prior diagnoses on numbers of new diagnoses. The relationship between partner services and linkage to care was evaluated with multivariable log-binomial regression models. Of the 2842 people who entered the King County HIV Surveillance System in 2010 to 2015, 52% were newly diagnosed, 41% had a confirmed prior diagnosis in another state, and 7% had an unconfirmed prior diagnosis. Twelve percent of those classified as newly diagnosed for purposes of national HIV surveillance self-reported a prior HIV diagnosis that was unconfirmed. Partner services recipients were more likely than nonrecipients to link to care within 30 days (adjusted risk ratio [RR] = 1.10; 95% confidence interval [CI] = 1.03, 1.18) and 90 days (adjusted RR = 1.07; 95% CI = 1.01, 1.14) of diagnosis. Integration of HIV surveillance, partner services, and care linkage efforts may improve the accuracy of HIV surveillance data and facilitate timely linkage to care.

Development of a mobbing short scale in the Gutenberg Health Study.

PubMed

Garthus-Niegel, Susan; Nübling, Matthias; Letzel, Stephan; Hegewald, Janice; Wagner, Mandy; Wild, Philipp S; Blettner, Maria; Zwiener, Isabella; Latza, Ute; Jankowiak, Sylvia; Liebers, Falk; Seidler, Andreas

2016-01-01

Despite its highly detrimental potential, most standard questionnaires assessing psychosocial stress at work do not include mobbing as a risk factor. In the German standard version of COPSOQ, mobbing is assessed with a single item. In the Gutenberg Health Study, this version was used together with a newly developed short scale based on the Leymann Inventory of Psychological Terror. The purpose of the present study was to evaluate the psychometric properties of these two measures, to compare them and to test their differential impact on relevant outcome parameters. This analysis is based on a population-based sample of 1441 employees participating in the Gutenberg Health Study. Exploratory and confirmatory factor analyses and reliability analyses were used to assess the mobbing scale. To determine their predictive validities, multiple linear regression analyses with six outcome parameters and log-binomial regression models for two of the outcome aspects were run. Factor analyses of the five-item scale confirmed a one-factor solution, reliability was α = 0.65. Both the single-item and the five-item scales were associated with all six outcome scales. Effect sizes were similar for both mobbing measures. Mobbing is an important risk factor for health-related outcomes. For the purpose of psychosocial risk assessment in the workplace, both the single-item and the five-item constructs were psychometrically appropriate. Associations with outcomes were about equivalent. However, the single item has the advantage of parsimony, whereas the five-item construct depicts several distinct forms of mobbing.

The Effect of Cotrimoxazole Prophylactic Treatment on Malaria, Birth Outcomes, and Postpartum CD4 Count in HIV-Infected Women

PubMed Central

Dow, Anna; Hudgens, Michael G.; Van Rie, Annelies; King, Caroline C.; Ellington, Sascha; Chome, Nelecy; Turner, Abigail Norris; Kacheche, Zebrone; Jamieson, Denise J.; Chasela, Charles; van der Horst, Charles

2013-01-01

Background. Limited data exist on cotrimoxazole prophylactic treatment (CPT) in pregnant women, including protection against malaria versus standard intermittent preventive therapy with sulfadoxine-pyrimethamine (IPTp). Methods. Using observational data we examined the effect of CPT in HIV-infected pregnant women on malaria during pregnancy, low birth weight and preterm birth using proportional hazards, logistic, and log binomial regression, respectively. We used linear regression to assess effect of CPT on CD4 count. Results. Data from 468 CPT-exposed and 768 CPT-unexposed women were analyzed. CPT was associated with protection against malaria versus IPTp (hazard ratio: 0.35, 95% Confidence Interval (CI): 0.20, 0.60). After adjustment for time period this effect was not statistically significant (adjusted hazard ratio: 0.66, 95% CI: 0.28, 1.52). Among women receiving and not receiving CPT, rates of low birth weight (7.1% versus 7.6%) and preterm birth (23.5% versus 23.6%) were similar. CPT was associated with lower CD4 counts 24 weeks postpartum in women receiving (−77.6 cells/μL, 95% CI: −125.2, −30.1) and not receiving antiretrovirals (−33.7 cells/μL, 95% CI: −58.6, −8.8). Conclusions. Compared to IPTp, CPT provided comparable protection against malaria in HIV-infected pregnant women and against preterm birth or low birth weight. Possible implications of CPT-associated lower CD4 postpartum warrant further examination. PMID:24363547

Peak Weight and Height Velocity to Age 36 Months and Asthma Development: The Norwegian Mother and Child Cohort Study

PubMed Central

Magnus, Maria C.; Stigum, Hein; Håberg, Siri E.; Nafstad, Per; London, Stephanie J.; Nystad, Wenche

2015-01-01

Background The immediate postnatal period is the period of the fastest growth in the entire life span and a critical period for lung development. Therefore, it is interesting to examine the association between growth during this period and childhood respiratory disorders. Methods We examined the association of peak weight and height velocity to age 36 months with maternal report of current asthma at 36 months (n = 50,311), recurrent lower respiratory tract infections (LRTIs) by 36 months (n = 47,905) and current asthma at 7 years (n = 24,827) in the Norwegian Mother and Child Cohort Study. Peak weight and height velocity was calculated using the Reed1 model through multilevel mixed-effects linear regression. Multivariable log-binomial regression was used to calculate adjusted relative risks (adj.RR) and 95% confidence intervals (CI). We also conducted a sibling pair analysis using conditional logistic regression. Results Peak weight velocity was positively associated with current asthma at 36 months [adj.RR 1.22 (95%CI: 1.18, 1.26) per standard deviation (SD) increase], recurrent LRTIs by 36 months [adj.RR 1.14 (1.10, 1.19) per SD increase] and current asthma at 7 years [adj.RR 1.13 (95%CI: 1.07, 1.19) per SD increase]. Peak height velocity was not associated with any of the respiratory disorders. The positive association of peak weight velocity and asthma at 36 months remained in the sibling pair analysis. Conclusions Higher peak weight velocity, achieved during the immediate postnatal period, increased the risk of respiratory disorders. This might be explained by an influence on neonatal lung development, shared genetic/epigenetic mechanisms and/or environmental factors. PMID:25635872

Serum Vitamin D Levels and Markers of Severity of Childhood Asthma in Costa Rica

PubMed Central

Brehm, John M.; Celedón, Juan C.; Soto-Quiros, Manuel E.; Avila, Lydiana; Hunninghake, Gary M.; Forno, Erick; Laskey, Daniel; Sylvia, Jody S.; Hollis, Bruce W.; Weiss, Scott T.; Litonjua, Augusto A.

2009-01-01

Rationale: Maternal vitamin D intake during pregnancy has been inversely associated with asthma symptoms in early childhood. However, no study has examined the relationship between measured vitamin D levels and markers of asthma severity in childhood. Objectives: To determine the relationship between measured vitamin D levels and both markers of asthma severity and allergy in childhood. Methods: We examined the relation between 25-hydroxyvitamin D levels (the major circulating form of vitamin D) and markers of allergy and asthma severity in a cross-sectional study of 616 Costa Rican children between the ages of 6 and 14 years. Linear, logistic, and negative binomial regressions were used for the univariate and multivariate analyses. Measurements and Main Results: Of the 616 children with asthma, 175 (28%) had insufficient levels of vitamin D (<30 ng/ml). In multivariate linear regression models, vitamin D levels were significantly and inversely associated with total IgE and eosinophil count. In multivariate logistic regression models, a log10 unit increase in vitamin D levels was associated with reduced odds of any hospitalization in the previous year (odds ratio [OR], 0.05; 95% confidence interval [CI], 0.004–0.71; P = 0.03), any use of antiinflammatory medications in the previous year (OR, 0.18; 95% CI, 0.05–0.67; P = 0.01), and increased airway responsiveness (a ≤8.58-μmol provocative dose of methacholine producing a 20% fall in baseline FEV1 [OR, 0.15; 95% CI, 0.024–0.97; P = 0.05]). Conclusions: Our results suggest that vitamin D insufficiency is relatively frequent in an equatorial population of children with asthma. In these children, lower vitamin D levels are associated with increased markers of allergy and asthma severity. PMID:19179486

[Analysis on prevalence of physical activity time <1 hour and related factors in students aged 9-22 years in China, 2014].

PubMed

Wang, Z H; Dong, Y H; Song, Y; Yang, Z P; Ma, J

2017-03-10

Objective: To explore the prevalence of physical activity time <1 hour and related factors in students aged 9-22 years in China. Methods: A total of 220 159 students (110 039 boys and 110 120 girls) aged 9-22 years who completed the questionnaire of physical activity and lifestyle behaviors were selected from " 2014 National Physical Fitness and Health Surveillance" for the current study. All the participants were divided into 2 groups, i.e. physical activity time <1 hour and physical activity time ≥1 hour according the suggestion of Central Government, stratified by age and gender. χ (2) tests were used to compare the difference in the prevalence of physical activity time <1 hour between boys and girls in every age groups. Univariate and multivariate log-binomial regression models were used to explore the factors that influenced the prevalence of physical activity time <1 hour. Results: The boy's prevalence of physical activity time <1 hour was 73.3%, with the lowest (57.0%) in 9-years-old group, and highest (82.5%) in 18 years old group. The girl's prevalence of physical activity time <1 hour was 79.1%, with the lowest (60.1%) in 9-years-old group, and highest (89.8%) in 21 years old group. Overall, The prevalence of physical activity time <1 hour was significantly higher in girls than in boys ( P <0.001), and the prevalence were significantly higher in girls than in boys in all the age groups ( P <0.001), and it was observed that the prevalence of physical activity <1 hour increased with age in both boys and girls ( P <0.001). Multivariate log-binomial regression model found that being girl ( PR =1.05, 95 %CI : 1.05-1.06), parents' disliking children to participate physical activity ( PR =1.08, 95 % CI : 1.07-1.09), heavy homework ( PR =1.13, 95 % CI : 1.12-1.14), long homework time ( PR =1.08, 95 %CI : 1.07-1.08), long time spending on electronic screen watching ( PR =1.01, 95 %CI : 1.00-1.01) and disliking physical class ( PR =1.11, 95 %CI : 1.10-1.12) could be the risk factors for physical activity time <1 hour, however, living in rural area ( PR =0.99, 95 % CI : 0.98-0.99) and no supporting from parents for children to participate physical activity ( PR =0.99, 95 %CI : 1.98-1.00) could be the protective factors, but no consistent association with the time of TV watching was observed ( P =0.226). Conclusions: The prevalence of physical activity time <1 hour was high in students aged 9-22 years in China. Female, parents; disliking children to participate physical activity, heavy homework, long homework time, long electronic screen watching time and disliking physical class might be the risk factors.

Comparing Environmental Influences on Coral Bleaching Across and within Species using Clustered Binomial Regression

EPA Science Inventory

Differential susceptibility among reef-building coral species can lead to community shifts and loss of diversity as a result of temperature-induced mass bleaching events. However, the influence of the local environment on species-specific bleaching susceptibilities has not been ...

School Violence: The Role of Parental and Community Involvement

ERIC Educational Resources Information Center

Lesneskie, Eric; Block, Steven

2017-01-01

This study utilizes the School Survey on Crime and Safety to identify variables that predict lower levels of violence from four domains: school security, school climate, parental involvement, and community involvement. Negative binomial regression was performed and the findings indicate that statistically significant results come from all four…

Predicting Children's Asthma Hospitalizations: Rural and Urban Differences in Texas

ERIC Educational Resources Information Center

Grineski, Sara E.

2009-01-01

Asthma is the number one chronic health condition facing children today; however, little is known about rural-urban inequalities in asthma. This "area effects on health" study examines rural-urban differences in childhood asthma hospitalizations within the state of Texas using negative binomial regression models. Effects associated with…

Trend estimation in populations with imperfect detection

USGS Publications Warehouse

Kery, Marc; Dorazio, Robert M.; Soldaat, Leo; Van Strien, Arco; Zuiderwijk, Annie; Royle, J. Andrew

2009-01-01

1. Trends of animal populations are of great interest in ecology but cannot be directly observed owing to imperfect detection. Binomial mixture models use replicated counts to estimate abundance, corrected for detection, in demographically closed populations. Here, we extend these models to open populations and illustrate them using sand lizard Lacerta agilis counts from the national Dutch reptile monitoring scheme. 2. Our model requires replicated counts from multiple sites in each of several periods, within which population closure is assumed. Counts are described by a hierarchical generalized linear model, where the state model deals with spatio-temporal patterns in true abundance and the observation model with imperfect counts, given that true state. We used WinBUGS to fit the model to lizard counts from 208 transects with 1–10 (mean 3) replicate surveys during each spring 1994–2005. 3. Our state model for abundance contained two independent log-linear Poisson regressions on year for coastal and inland sites, and random site effects to account for unexplained heterogeneity. The observation model for detection of an individual lizard contained effects of region, survey date, temperature, observer experience and random survey effects. 4. Lizard populations increased in both regions but more steeply on the coast. Detectability increased over the first few years of the study, was greater on the coast and for the most experienced observers, and highest around 1 June. Interestingly, the population increase inland was not detectable when the observed counts were analysed without account of detectability. The proportional increase between 1994 and 2005 in total lizard abundance across all sites was estimated at 86% (95% CRI 35–151). 5. Synthesis and applications. Open-population binomial mixture models are attractive for studying true population dynamics while explicitly accounting for the observation process, i.e. imperfect detection. We emphasize the important conceptual benefit provided by temporal replicate observations in terms of the interpretability of animal counts.

Effects of Cognition, Function, and Behavioral and Psychological Symptoms on Medicare Expenditures and Health Care Utilization for Persons With Dementia.

PubMed

Jutkowitz, Eric; Kane, Robert L; Dowd, Bryan; Gaugler, Joseph E; MacLehose, Richard F; Kuntz, Karen M

2017-06-01

Clinical features of dementia (cognition, function, and behavioral/psychological symptoms [BPSD]) may differentially affect Medicare expenditures/health care utilization. We linked cross-sectional data from the Aging, Demographics, and Memory Study to Medicare data to evaluate the association between dementia clinical features among those with dementia and Medicare expenditures/health care utilization (n = 234). Cognition was evaluated using the Mini-Mental State Examination (MMSE). Function was evaluated as the number of functional limitations (0-10). BPSD was evaluated as the number of symptoms (0-12). Expenditures were estimated with a generalized linear model (log-link and gamma distribution). Number of hospitalizations, institutional outpatient visits, and physician visits were estimated with a negative binomial regression. Medicare covered skilled nursing days were estimated with a zero-inflated negative binomial model. Cognition and BPSD were not associated with expenditures. Among individuals with less than seven functional limitations, one additional limitation was associated with $123 (95% confidence interval: $19-$227) additional monthly Medicare spending. Better cognition and poorer function were associated with more hospitalizations among those with an MMSE less than three and less than six functional limitations, respectively. BPSD had no effect on hospitalizations. Poorer function and fewer BPSD were associated with more skilled nursing among individuals with one to seven functional limitations and more than four symptoms, respectively. Cognition had no effect on skilled nursing care. No clinical feature was associated with institutional outpatient care. Of individuals with an MMSE less than 15, poorer cognition was associated with fewer physician visits. Among those with more than six functional limitations, poorer function was associated with fewer physician visits. Poorer function, not cognition or BPSD, was associated with higher Medicare expenditures. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A Multi-temporal Analysis of Logging Impacts on Tropical Forest Structure Using Airborne Lidar Data

NASA Astrophysics Data System (ADS)

Keller, M. M.; Pinagé, E. R.; Duffy, P.; Longo, M.; dos-Santos, M. N.; Leitold, V.; Morton, D. C.

2017-12-01

The long-term impacts of selective logging on carbon cycling and ecosystem function in tropical-forests are still uncertain. Despite improvements in selective logging detection using satellite data, quantifying changes in forest structure from logging and recovery following logging is difficult using orbital data. We analyzed the dynamics of forest structure comparing logged and unlogged forests in the Eastern Brazilian Amazon (Paragominas Municipality, Pará State) using small footprint discrete return airborne lidar data acquired in 2012 and 2014. Logging operations were conducted at the 1200 ha study site from 2006 through 2013 using reduced impact logging techniques—management practices that minimize canopy and ground damage compared to more common conventional logging. Nevertheless, logging still reduced aboveground biomass by 10% to 20% in logged areas compared to intact forests. We aggregated lidar point-cloud data at spatial scales ranging from 50 m to 250 m and developed a binomial classification model based on the height distribution of lidar returns in 2012 and validated the model against the 2014 lidar acquisition. We accurately classified intact and logged forest classes compared with field data. Classification performance improved as spatial resolution increased (AUC = 0.974 at 250 m). We analyzed the differences in canopy gaps, understory damage (based on a relative density model), and biomass (estimated from total canopy height) of intact and logged classes. As expected, logging greatly increased both canopy gap formation and understory damage. However, while the area identified as canopy gap persisted for at least 8 years (from the oldest logging treatments in 2006 to the most recent lidar acquisition in 2014), the effects of ground damage were mostly erased by vigorous understory regrowth after about 5 years. The rate of new gap formation was 6 to 7 times greater in recently logged forests compared to undisturbed forests. New gaps opened at a rate of 1.8 times greater than background even 8 years following logging demonstrating the occurrence of delayed tree mortality. Our study showed that even low-intensity anthropogenic disturbances can cause persistent changes in tropical forest structure and dynamics.

Gaussian Process Regression Model in Spatial Logistic Regression

NASA Astrophysics Data System (ADS)

Sofro, A.; Oktaviarina, A.

2018-01-01

Spatial analysis has developed very quickly in the last decade. One of the favorite approaches is based on the neighbourhood of the region. Unfortunately, there are some limitations such as difficulty in prediction. Therefore, we offer Gaussian process regression (GPR) to accommodate the issue. In this paper, we will focus on spatial modeling with GPR for binomial data with logit link function. The performance of the model will be investigated. We will discuss the inference of how to estimate the parameters and hyper-parameters and to predict as well. Furthermore, simulation studies will be explained in the last section.

An empirical model for estimating annual consumption by freshwater fish populations

USGS Publications Warehouse

Liao, H.; Pierce, C.L.; Larscheid, J.G.

2005-01-01

Population consumption is an important process linking predator populations to their prey resources. Simple tools are needed to enable fisheries managers to estimate population consumption. We assembled 74 individual estimates of annual consumption by freshwater fish populations and their mean annual population size, 41 of which also included estimates of mean annual biomass. The data set included 14 freshwater fish species from 10 different bodies of water. From this data set we developed two simple linear regression models predicting annual population consumption. Log-transformed population size explained 94% of the variation in log-transformed annual population consumption. Log-transformed biomass explained 98% of the variation in log-transformed annual population consumption. We quantified the accuracy of our regressions and three alternative consumption models as the mean percent difference from observed (bioenergetics-derived) estimates in a test data set. Predictions from our population-size regression matched observed consumption estimates poorly (mean percent difference = 222%). Predictions from our biomass regression matched observed consumption reasonably well (mean percent difference = 24%). The biomass regression was superior to an alternative model, similar in complexity, and comparable to two alternative models that were more complex and difficult to apply. Our biomass regression model, log10(consumption) = 0.5442 + 0.9962??log10(biomass), will be a useful tool for fishery managers, enabling them to make reasonably accurate annual population consumption predictions from mean annual biomass estimates. ?? Copyright by the American Fisheries Society 2005.

Brief Report: HIV Assisted Partner Services Among Those With and Without a History of Intimate Partner Violence in Kenya.

PubMed

Goyette, Marielle S; Mutiti, Peter M; Bukusi, David; Wamuti, Beatrice M; Otieno, Felix A; Cherutich, Peter; Golden, Matthew R; Spiegel, Hans; Richardson, Barbra A; Ngʼangʼa, Anne; Farquhar, Carey

2018-05-01

HIV assisted partner services (APS) are a notification and testing strategy for sex partners of HIV-infected index patients. This cluster-randomized controlled trial secondary data analysis investigated whether history of intimate partner violence (IPV) modified APS effectiveness and risk of relationship dissolution. Eighteen HIV testing and counseling sites in Kenya randomized to provide immediate APS (intervention) or APS delayed for 6 weeks (control). History of IPV was ascertained at study enrollment and defined as reporting ever experiencing physical or sexual IPV. Those reporting IPV in the month before enrollment were excluded. We tested whether history of IPV modified intervention effectiveness and risk of relationship dissolution using population-averaged Poisson and log-binomial generalized estimating equation models. Exploratory analyses investigated associations between history of IPV and events that occurred after HIV diagnosis using log-binomial generalized estimating equation models. The study enrolled 1119 index participants and 1286 partners. Among index participants, 81 (7%) had history of IPV. History of IPV did not modify APS effectiveness in testing, newly diagnosing, or linking partners to care. History of IPV did not modify the association between receiving immediate APS and relationship dissolution during the study. Among participants who had not experienced IPV in the last month but had experienced IPV in their lifetimes, our results suggest that APS is an effective and safe partner notification strategy in Kenya. As APS is scaled up in different contexts, these data support including those reporting past IPV and closely monitoring adverse events.

A Binomial Modeling Approach for Upscaling Colloid Transport Under Unfavorable Attachment Conditions: Emergent Prediction of Nonmonotonic Retention Profiles

NASA Astrophysics Data System (ADS)

Hilpert, Markus; Johnson, William P.

2018-01-01

We used a recently developed simple mathematical network model to upscale pore-scale colloid transport information determined under unfavorable attachment conditions. Classical log-linear and nonmonotonic retention profiles, both well-reported under favorable and unfavorable attachment conditions, respectively, emerged from our upscaling. The primary attribute of the network is colloid transfer between bulk pore fluid, the near-surface fluid domain (NSFD), and attachment (treated as irreversible). The network model accounts for colloid transfer to the NSFD of downgradient grains and for reentrainment to bulk pore fluid via diffusion or via expulsion at rear flow stagnation zones (RFSZs). The model describes colloid transport by a sequence of random trials in a one-dimensional (1-D) network of Happel cells, which contain a grain and a pore. Using combinatorial analysis that capitalizes on the binomial coefficient, we derived from the pore-scale information the theoretical residence time distribution of colloids in the network. The transition from log-linear to nonmonotonic retention profiles occurs when the conditions underlying classical filtration theory are not fulfilled, i.e., when an NSFD colloid population is maintained. Then, nonmonotonic retention profiles result potentially both for attached and NSFD colloids. The concentration maxima shift downgradient depending on specific parameter choice. The concentration maxima were also shown to shift downgradient temporally (with continued elution) under conditions where attachment is negligible, explaining experimentally observed downgradient transport of retained concentration maxima of adhesion-deficient bacteria. For the case of zero reentrainment, we develop closed-form, analytical expressions for the shape, and the maximum of the colloid retention profile.

Modeling species-abundance relationships in multi-species collections

USGS Publications Warehouse

Peng, S.; Yin, Z.; Ren, H.; Guo, Q.

2003-01-01

Species-abundance relationship is one of the most fundamental aspects of community ecology. Since Motomura first developed the geometric series model to describe the feature of community structure, ecologists have developed many other models to fit the species-abundance data in communities. These models can be classified into empirical and theoretical ones, including (1) statistical models, i.e., negative binomial distribution (and its extension), log-series distribution (and its extension), geometric distribution, lognormal distribution, Poisson-lognormal distribution, (2) niche models, i.e., geometric series, broken stick, overlapping niche, particulate niche, random assortment, dominance pre-emption, dominance decay, random fraction, weighted random fraction, composite niche, Zipf or Zipf-Mandelbrot model, and (3) dynamic models describing community dynamics and restrictive function of environment on community. These models have different characteristics and fit species-abundance data in various communities or collections. Among them, log-series distribution, lognormal distribution, geometric series, and broken stick model have been most widely used.

Multivariate regression model for predicting yields of grade lumber from yellow birch sawlogs

Treesearch

Andrew F. Howard; Daniel A. Yaussy

1986-01-01

A multivariate regression model was developed to predict green board-foot yields for the common grades of factory lumber processed from yellow birch factory-grade logs. The model incorporates the standard log measurements of scaling diameter, length, proportion of scalable defects, and the assigned USDA Forest Service log grade. Differences in yields between band and...

Racial Threat and White Opposition to Bilingual Education in Texas

ERIC Educational Resources Information Center

Hempel, Lynn M.; Dowling, Julie A.; Boardman, Jason D.; Ellison, Christopher G.

2013-01-01

This study examines local contextual conditions that influence opposition to bilingual education among non-Hispanic Whites, net of individual-level characteristics. Data from the Texas Poll (N = 615) are used in conjunction with U.S. Census data to test five competing hypotheses using binomial and multinomial logistic regression models. Our…

General Strain Theory as a Basis for the Design of School Interventions

ERIC Educational Resources Information Center

Moon, Byongook; Morash, Merry

2013-01-01

The research described in this article applies general strain theory to identify possible points of intervention for reducing delinquency of students in two middle schools. Data were collected from 296 youths, and separate negative binomial regression analyses were used to identify predictors of violent, property, and status delinquency. Emotional…

The Effectiveness of an Electronic Security Management System in a Privately Owned Apartment Complex

ERIC Educational Resources Information Center

Greenberg, David F.; Roush, Jeffrey B.

2009-01-01

Poisson and negative binomial regression methods are used to analyze the monthly time series data to determine the effects of introducing an integrated security management system including closed-circuit television (CCTV), door alarm monitoring, proximity card access, and emergency call boxes to a large privately-owned complex of apartment…

Campaign Strategies and Voter Approval of School Referenda: A Mixed Methods Analysis

ERIC Educational Resources Information Center

Johnson, Paul A.; Ingle, William Kyle

2009-01-01

Drawing from state administrative data and surveys of superintendents in Ohio, this mixed methods study examined factors associated with voters' approval of local school levies. Utilizing binomial logistic regression, this study found that new levies and poverty rates were significantly associated with a decrease in the likelihood of passage.…

Socio-environmental predictors of Barmah forest virus transmission in coastal areas, Queensland, Australia.

PubMed

Naish, Suchithra; Hu, Wenbiao; Nicholls, Neville; Mackenzie, John S; Dale, Pat; McMichael, Anthony J; Tong, Shilu

2009-02-01

To assess the socio-environmental predictors of Barmah forest virus (BFV) transmission in coastal areas, Queensland, Australia. Data on BFV notified cases, climate, tidal levels and socioeconomic index for area (SEIFA) in six coastal cities, Queensland, for the period 1992-2001 were obtained from the relevant government agencies. Negative binomial regression models were used to assess the socio-environmental predictors of BFV transmission. The results show that maximum and minimum temperature, rainfall, relative humidity, high and low tide were statistically significantly associated with BFV incidence at lags 0-2 months. The fitted negative binomial regression models indicate a significant independent association of each of maximum temperature (beta = 0.139, P = 0.000), high tide (beta = 0.005, P = 0.000) and SEIFA index (beta = -0.010, P = 0.000) with BFV transmission after adjustment for confounding variables. The transmission of BFV disease in Queensland coastal areas seemed to be determined by a combination of local social and environmental factors. The model developed in this study may have applications in the control and prevention of BFV disease in these areas.

Statistical models for RNA-seq data derived from a two-condition 48-replicate experiment.

PubMed

Gierliński, Marek; Cole, Christian; Schofield, Pietà; Schurch, Nicholas J; Sherstnev, Alexander; Singh, Vijender; Wrobel, Nicola; Gharbi, Karim; Simpson, Gordon; Owen-Hughes, Tom; Blaxter, Mark; Barton, Geoffrey J

2015-11-15

High-throughput RNA sequencing (RNA-seq) is now the standard method to determine differential gene expression. Identifying differentially expressed genes crucially depends on estimates of read-count variability. These estimates are typically based on statistical models such as the negative binomial distribution, which is employed by the tools edgeR, DESeq and cuffdiff. Until now, the validity of these models has usually been tested on either low-replicate RNA-seq data or simulations. A 48-replicate RNA-seq experiment in yeast was performed and data tested against theoretical models. The observed gene read counts were consistent with both log-normal and negative binomial distributions, while the mean-variance relation followed the line of constant dispersion parameter of ∼0.01. The high-replicate data also allowed for strict quality control and screening of 'bad' replicates, which can drastically affect the gene read-count distribution. RNA-seq data have been submitted to ENA archive with project ID PRJEB5348. g.j.barton@dundee.ac.uk. © The Author 2015. Published by Oxford University Press.

Statistical models for RNA-seq data derived from a two-condition 48-replicate experiment

PubMed Central

Cole, Christian; Schofield, Pietà; Schurch, Nicholas J.; Sherstnev, Alexander; Singh, Vijender; Wrobel, Nicola; Gharbi, Karim; Simpson, Gordon; Owen-Hughes, Tom; Blaxter, Mark; Barton, Geoffrey J.

2015-01-01

Motivation: High-throughput RNA sequencing (RNA-seq) is now the standard method to determine differential gene expression. Identifying differentially expressed genes crucially depends on estimates of read-count variability. These estimates are typically based on statistical models such as the negative binomial distribution, which is employed by the tools edgeR, DESeq and cuffdiff. Until now, the validity of these models has usually been tested on either low-replicate RNA-seq data or simulations. Results: A 48-replicate RNA-seq experiment in yeast was performed and data tested against theoretical models. The observed gene read counts were consistent with both log-normal and negative binomial distributions, while the mean-variance relation followed the line of constant dispersion parameter of ∼0.01. The high-replicate data also allowed for strict quality control and screening of ‘bad’ replicates, which can drastically affect the gene read-count distribution. Availability and implementation: RNA-seq data have been submitted to ENA archive with project ID PRJEB5348. Contact: g.j.barton@dundee.ac.uk PMID:26206307

Pulmonary function tests do not predict mortality in patients undergoing continuous-flow left ventricular assist device implantation.

PubMed

Bedzra, Edo K S; Dardas, Todd F; Cheng, Richard K; Pal, Jay D; Mahr, Claudius; Smith, Jason W; Shively, Kent; Masri, S Carolina; Levy, Wayne C; Mokadam, Nahush A

2017-12-01

To investigate the effect of pulmonary function testing on outcomes after continuous flow left ventricular assist device implantation. A total of 263 and 239 patients, respectively, had tests of forced expiratory volume in 1 second and diffusing capacity of the lungs for carbon monoxide preoperatively for left ventricular assist device implantations between July 2005 and September 2015. Kaplan-Meier analysis and multivariable Cox regressions were performed to evaluate mortality. Patients were analyzed in a single cohort and across 5 groups. Postoperative intensive care unit and hospital lengths of stay were evaluated with negative binomial regressions. There is no association of forced expiratory volume in 1 second and diffusing capacity of the lungs for carbon monoxide with survival and no difference in mortality at 1 and 3 years between the groups (log rank P = .841 and .713, respectively). Greater values in either parameter were associated with decreased hospital lengths of stay. Only diffusing capacity of the lungs for carbon monoxide was associated with increased intensive care unit length of stay in the group analysis (P = .001). Ventilator times, postoperative pneumonia, reintubation, and tracheostomy rates were similar across the groups. Forced expiratory volume in 1 second and diffusing capacity of the lungs for carbon monoxide are not associated with operative or long-term mortality in patients undergoing continuous flow left ventricular assist device implantation. These findings suggest that these abnormal pulmonary function tests alone should not preclude mechanical circulatory support candidacy. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Validation of a questionnaire on hand hygiene in the construction industry.

PubMed

Timmerman, Johan G; Zilaout, Hicham; Heederik, Dick; Spee, Ton; Smit, Lidwien A M

2014-10-01

Construction workers are at risk of developing occupational contact dermatitis. Gloves, when used properly, may protect against chemicals and coarse materials. We investigated the prevalence and determinants of contact dermatitis in a population of Dutch construction workers and aimed at validating questionnaire items on hand hygiene. A cross-sectional study was conducted at 13 construction sites, yielding data of 177 subjects (95% response rate). A questionnaire covering questions on hand hygiene and contact dermatitis symptoms was used. Agreement between workplace observations and a number of questionnaire items was assessed by calculating Cohen's kappa. Log-binomial regression analysis was used to assess the association between contact dermatitis and various hand hygiene-related determinants. The 1-year prevalence of self-reported contact dermatitis in our study sample was 46.9%. Multiple regression analysis showed a positive association with difficulties with hand cleaning (prevalence ratio [PR]: 1.26, 95% confidence interval [CI]: 1.05-1.52), hand contamination at the end of the working day (PR: 2.30, 95% CI: 1.14-4.65), and intensive hand cream use (PR: 2.07, 95% CI: 1.42-3.01). Observations of hand contamination, glove use, and glove types were found to agree well with the self-reported data from the questionnaire (Cohen's kappa's 0.75, 0.97, and 0.88). Self-reported contact dermatitis prevalence in construction workers was high and related to hand hygiene. A strong agreement was found between workplace observations and self-reported questionnaire data. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Apgar score and dental caries risk in the primary dentition of five year olds.

PubMed

Sanders, A E; Slade, G D

2010-09-01

Conditions in utero and early life underlie risk for several childhood disorders. This study tested the hypothesis that the Apgar score predicted dental caries in the primary dentition. A retrospective cohort study conducted in 2003 examined associations between conditions at birth and early life with dental caries experience at five years. Dental examination data for a random sample of five-year-old South Australian children were obtained from School Dental Service electronic records. A questionnaire mailed to the parents obtained information about neonatal status at delivery (five-minute Apgar score, birthweight, plurality, gestational age) and details about birth order, weaning, and behavioural, familial and sociodemographic characteristics. Of the 1398 sampled children with a completed questionnaire (response rate=64.6%), 1058 were singleton term deliveries among whom prevalence of dental caries was 40.1%. In weighted log-binomial regression analysis, children with an Apgar score of <=8 relative to a score of 9-10 had greater probability of dental caries in the primary dentition after adjusting for sociodemographic and behavioural covariates and water fluoridation concentration (adjusted PR=1.47, 95% CI=1.11, 1.95). Readily accessible markers of early life, such as the Apgar score, may guide clinicians in identifying children at potentially heightened risk for dental caries and aid decision-making in allocating preventive services.

Maternal Language and Adverse Birth Outcomes in a Statewide Analysis

PubMed Central

Sentell, Tetine; Chang, Ann; Jun Ahn, Hyeong; Miyamura, Jill

2016-01-01

Background Limited English proficiency is associated with disparities across diverse health outcomes. However, evidence regarding adverse birth outcomes across languages is limited, particularly among US Asian and Pacific Islander populations. The study goal was to consider the relationship of maternal language to birth outcomes using statewide hospitalization data. Methods Detailed discharge data from Hawai‘i childbirth hospitalizations from 2012 (n=11,419) were compared by maternal language (English language or not) for adverse outcomes using descriptive and multivariable log-binomial regression models, controlling for race/ethnicity, age group, and payer. Results Ten percent of mothers spoke a language other than English; 93% of these spoke an Asian or Pacific Islander language. In multivariable models, compared to English speakers non-English speakers had significantly higher risk (adjusted relative risk [ARR]: 2.02; 95% Confidence Interval [CI]: 1.34–3.04) of obstetric trauma in vaginal deliveries without instrumentation. Some significant variation was seen by language for other birth outcomes, including an increased rate of primary Caesarean sections and vaginal births after Caesarean among non-English speakers. Conclusions Non-English speakers had approximately two times higher risk of having an obstetric trauma during a vaginal birth when other factors, including race/ethnicity, were controlled. Non-English speakers also had higher rates of potentially high-risk deliveries. PMID:26361937

Dose-response association between salivary cotinine levels and Mycobacterium tuberculosis infection.

PubMed

Shin, S S; Laniado-Laborin, R; Moreno, P G; Novotny, T E; Strathdee, S A; Garfein, R S

2013-11-01

Tijuana, Mexico. To describe the association between salivary cotinine levels and interferon-gamma (IFN-γ) release assay results. We conducted a cross-sectional study among injection drug users. Salivary cotinine levels were measured using NicAlert, a semi-quantitative dipstick assay. QuantiFERON©-TB Gold In-Tube (QFT-GIT) was used to determine Mycobacterium tuberculosis infection. Among 234 participants, the prevalence of QFT-GIT positivity for NicAlert cotinine categories 0 (non-smoking), 1 (second-hand smoke exposure or low-level smoking) and 26 (regular smoking) were respectively 42.1%, 46.4% and 65.2% (Ptrend 0.012). We found increasing trends in QFT-GIT positivity (Ptrend 0.003) and IFN-γ concentrations (Spearman's r 0.200, P 0.002) across cotinine levels 0 to 6. In multivariable log-binomial regression models adjusted for education, cotinine levels were not associated with QFT-GIT positivity when included as smoking categories (1 and 26 vs. 0), but were independently associated with QFT-GIT positivity when included as an ordinal variable (prevalence ratio 1.09 per 1 cotinine level, 95%CI 1.021.16). Our findings suggest that a dose-response relationship exists between tobacco smoke exposure and M. tuberculosis infection. Longitudinal studies that use biochemical measures for smoking status are needed to confirm our findings.

Induced abortion in a Southern European region: examining inequalities between native and immigrant women.

PubMed

Rodriguez-Alvarez, Elena; Borrell, Luisa N; González-Rábago, Yolanda; Martín, Unai; Lanborena, Nerea

2016-09-01

To examine induced abortion (IA) inequalities between native and immigrant women in a Southern European region and whether these inequalities depend on a 2010 Law facilitating IA. We conducted two analyses: (1) prevalence of total IAs, repeat and second trimester IA, in native and immigrant women aged 12-49 years for years 2009-2013 according to country of origin; and (2) log-binomial regression was used to quantify the association of place of origin with repeat and second trimester IAs among women with IAs. Immigrants were more likely to have an IA than Spanish women, with the highest probability in Sub-Saharan Africa (PR 8.32 95 % CI 3.66-18.92). Immigrant women with an IA from countries other than Maghreb and Asia have higher probabilities of a repeat IA than women from Spain. Women from Europe non-EU/Romania were 50 % (95 % CI 0.30-0.79) less likely to have a second trimester IA, while women from Central America/Caribbean were 45 % (95 % CI 1.11-1.89) more likely than Spanish women. The 2010 Law did not affect these associations. There is a need for parenthood planning programs and more information and access to contraception methods especially in immigrant women to help decrease IAs.

Maternal language and adverse birth outcomes in a statewide analysis.

PubMed

Sentell, Tetine; Chang, Ann; Ahn, Hyeong Jun; Miyamura, Jill

2016-01-01

Limited English proficiency is associated with disparities across diverse health outcomes. However, evidence regarding adverse birth outcomes across languages is limited, particularly among U.S. Asian and Pacific Islander populations. The study goal was to consider the relationship of maternal language to birth outcomes using statewide hospitalization data. Detailed discharge data from Hawaii childbirth hospitalizations from 2012 (n = 11,419) were compared by maternal language (English language or not) for adverse outcomes using descriptive and multivariable log-binomial regression models, controlling for race/ethnicity, age group, and payer. Ten percent of mothers spoke a language other than English; 93% of these spoke an Asian or Pacific Islander language. In multivariable models, compared to English speakers, non-English speakers had significantly higher risk (adjusted relative risk [ARR]: 2.02; 95% confidence interval [CI]: 1.34-3.04) of obstetric trauma in vaginal deliveries without instrumentation. Some significant variation was seen by language for other birth outcomes, including an increased rate of primary Caesarean sections and vaginal births after Caesarean, among non-English speakers. Non-English speakers had approximately two times higher risk of having an obstetric trauma during a vaginal birth when other factors, including race/ethnicity, were controlled. Non-English speakers also had higher rates of potentially high-risk deliveries.

Gender and socioeconomic status in relation to weight perception and weight control behavior in Korean adults.

PubMed

Joh, Hee-Kyung; Oh, Juhwan; Lee, Hae-Jeung; Kawachi, Ichiro

2013-01-01

In Korea, obesity is more prevalent among men and lower socioeconomic groups. To explain this obesity disparity, we compared weight perception and weight control behavior across gender and socioeconomic status (SES). We analyzed data from 16,260 participants aged 20 years or older in a nationally representative cross-sectional survey. SES indicators included education and income levels. Weight under-perception was defined when participants considered themselves lighter than their measured BMI status. Either no active or inappropriate weight control (i.e., trying to gain weight in obese individuals) was considered to be unhealthy patterns. Multivariate prevalence ratios were calculated using log-binomial regressions. Men had a higher prevalence of weight under-perception (24.5 vs. 11.9%) and unhealthy patterns of weight control behavior (57 vs. 40%) than women. Low education level was associated with weight under-perception (ptrend = 0.022 in men, ptrend < 0.001 in women). Both education and income levels were significantly associated with patterns of weight control behavior (for education: ptrend < 0.001 in men and women; for income: ptrend = 0.047 in men, ptrend < 0.001 in women). Weight perception and weight control behavior significantly varied by gender and SES. Public actions should be directed toward improving perception and behavior of high-risk populations.

Physical activity patterns and metabolic syndrome in Costa Rica

PubMed Central

Hastert, Theresa A.; Gong, Jian; Campos, Hannia; Baylin, Ana

2015-01-01

Objective To examine whether total physical activity or activity patterns are associated with metabolic syndrome and its components. Methods Participants include 1,994 controls from a case-control study of non-fatal myocardial infarction in Costa Rica (1994–2004). Physical activity was assessed via self-administered questionnaire and patterns were identified using principal components analysis. Metabolic syndrome was assessed via blood samples and anthropometry measurements from in-home study visits. Prevalence ratios (PR) and 95% confidence intervals (CI) were calculated using log binomial regression. Adjusted least squares means of metabolic syndrome components were calculated by quintile of total activity and pattern scores. Results Four activity patterns were identified: rest/sleep, agricultural, light indoor activity, and manual labor. Total activity was not associated with metabolic syndrome. Metabolic syndrome prevalence was 20% lower in participants with the highest scores on the agricultural job pattern compared to those with the lowest (PR: 0.80, 95% CI: 0.68–0.94). Higher total activity was associated with lower triglycerides and lower HDL cholesterol. Higher scores on each pattern were inversely associated with metabolic syndrome components, particularly waist circumference and fasting blood glucose. Conclusions Patterns or types of physical activity may be more strongly associated with metabolic syndrome and its components than total activity levels. PMID:25445330

Social-environmental factors and protective sexual behavior among sex workers: the Encontros intervention in Brazil.

PubMed

Lippman, Sheri A; Donini, Angela; Díaz, Juan; Chinaglia, Magda; Reingold, Arthur; Kerrigan, Deanna

2010-04-01

We sought to determine the association of social-environmental factors with condom use and sexually transmitted infections (STIs) among 420 sex workers participating in an STI/HIV prevention study in Corumbá, Brazil, to inform future intervention efforts. Participants provided urine samples for polymerase chain reaction testing of chlamydia and gonorrhea and responded to multi-item scales addressing perceived social cohesion, participation in networks, and access to and management of resources. We conducted multivariate log-linear and negative binomial regression analyses of these data. Increased social cohesion was inversely associated with number of unprotected sex acts in the preceding week among women (adjusted incidence rate ratio [IRR] = 0.80; P < .01), and there was a marginal association among men (adjusted IRR = 0.41; P = .08). Women's increased participation in social networks was associated with a decrease in frequency of unprotected sex acts (adjusted IRR = 0.83; P = .04), as was men's access to and management of social and material resources (IRR = 0.15; P = .01). Social-environmental factors were not associated with STIs. The social context within which populations negotiate sexual behaviors is associated with condom use. Future efforts to prevent STI/HIV should incorporate strategies to modify the social environment.

Social-Environmental Factors and Protective Sexual Behavior Among Sex Workers: The Encontros Intervention in Brazil

PubMed Central

Donini, Angela; Díaz, Juan; Chinaglia, Magda; Reingold, Arthur; Kerrigan, Deanna

2010-01-01

Objectives. We sought to determine the association of social–environmental factors with condom use and sexually transmitted infections (STIs) among 420 sex workers participating in an STI/HIV prevention study in Corumbá, Brazil, to inform future intervention efforts. Methods. Participants provided urine samples for polymerase chain reaction testing of chlamydia and gonorrhea and responded to multi-item scales addressing perceived social cohesion, participation in networks, and access to and management of resources. We conducted multivariate log-linear and negative binomial regression analyses of these data. Results. Increased social cohesion was inversely associated with number of unprotected sex acts in the preceding week among women (adjusted incidence rate ratio [IRR] = 0.80; P < .01), and there was a marginal association among men (adjusted IRR = 0.41; P = .08). Women's increased participation in social networks was associated with a decrease in frequency of unprotected sex acts (adjusted IRR = 0.83; P = .04), as was men's access to and management of social and material resources (IRR = 0.15; P = .01). Social–environmental factors were not associated with STIs. Conclusions. The social context within which populations negotiate sexual behaviors is associated with condom use. Future efforts to prevent STI/HIV should incorporate strategies to modify the social environment. PMID:19762673

Older maternal age is associated with depression, anxiety, and stress symptoms in young adult female offspring.

PubMed

Tearne, Jessica E; Robinson, Monique; Jacoby, Peter; Allen, Karina L; Cunningham, Nadia K; Li, Jianghong; McLean, Neil J

2016-01-01

The evidence regarding older parental age and incidence of mood disorder symptoms in offspring is limited, and that which exists is mixed. We sought to clarify these relationships by using data from the Western Australian Pregnancy Cohort (Raine) Study. The Raine Study provided comprehensive data from 2,900 pregnancies, resulting in 2,868 live born children. A total of 1,220 participants completed the short form of the Depression Anxiety Stress Scale (DASS-21) at the 20-year cohort follow-up. We used negative binomial regression analyses with log link and with adjustment for known perinatal risk factors to examine the extent to which maternal and paternal age at childbirth predicted continuous DASS-21 index scores. In the final multivariate models, a maternal age of 30-34 years was associated with significant increases in stress DASS-21 scores in female offspring relative to female offspring of 25- to 29-year-old mothers. A maternal age of 35 years and over was associated with increased scores on all DASS-21 scales in female offspring. Our results indicate that older maternal age is associated with depression, anxiety, and stress symptoms in young adult females. Further research into the mechanisms underpinning this relationship is needed. (c) 2016 APA, all rights reserved.

Perceived discrimination and self-rated health in the immigrant population of the Basque Country, Spain.

PubMed

Rodríguez-Álvarez, Elena; González-Rábago, Yolanda; Borrell, Luisa N; Lanborena, Nerea

To examine the effect of perceived discrimination and self-rated health among the immigrant population in the Basque Country, Spain, and determine whether this effect varies according to region of origin, age, sex and education. Descriptive cross-sectional study. The study population included immigrants aged 18 and older residing in the Basque Country. Data from the 2014 Foreign Immigrant Population Survey (n=3,456) were used. Log-binomial regression was used to quantify the association between perceived discrimination and self-rated health before and after checking for the selected characteristics. Almost 1 in 10 immigrant adults reports perceiving discrimination. In adjusted analyses, the immigrants perceiving discrimination were almost were 1.92 more likely to rate their health as poor (prevalence ratio: 1.92; 95% CI: 1.44-2.56) than those who did not report discrimination. This association did not vary according to region of origin, age, sex or educational level. Perceived discrimination shows a consistent relationship with perceived health. Moreover, this association did not depend on the region of origin, age, sex or educational level of immigrants. These results show the need for implementing inclusive policies to eliminate individual and institutional discrimination and reduce health inequalities between the immigrant and native populations. Copyright © 2017. Publicado por Elsevier España, S.L.U.

A modified fetal heart rate tracing interpretation system for prediction of cesarean section

PubMed Central

Schnettler, William T.; Rogers, Jennifer; Barber, Rachel E.; Hacker, Michele R.

2013-01-01

Objective To investigate whether a modified version of the 2008 National Institute of Child Health and Human Development (NICHD) interpretation system upon admission decreases cesarean delivery risk. Methods This retrospective cohort study ascribed a modified category to the first 30 min of fetal heart rate (FHR) tracings in labor. Category I was divided into two subsets (Ia and Ib) by the presence of accelerations. Category II was divided into four subsets (IIa–IId) based on baseline FHR, variability, response to stimulation and decelerations. Log-binomial regression was used to calculate risk ratios (RR) and 95% confidence intervals (CI). Results A category was ascribed to 910 women. Most FHR tracings were Category Ia (65.8%), Ib (7.7%), IIb (11.8%) and IId (14.0%). Category Ib tracings (fewer than two accelerations) were 2.26 (95% CI: 1.13–4.52) times more likely to result in cesarean delivery for abnormal FHR tracing than Category Ia tracings. A similar increase in risk was seen when comparing Category IIb and Category IId with Category Ia. Conclusion Application of a modified version of the 2008 NICHD FHR interpretation system to the initial 30 min of labor can identify women at increased risk of cesarean delivery for abnormal FHR tracing. PMID:21942513

Racial and ethnic disparities in universal cervical length screening with transvaginal ultrasound

PubMed Central

Haviland, Miriam J; Shainker, Scott A; Hacker, Michele R; Burris, Heather H

2016-01-01

Objective Determine if race or ethnicity is associated with missed or late transvaginal cervical length screening in a universal screening program. Methods Retrospective cohort study of nulliparous women with singleton gestations and a fetal anatomical ultrasound from 16-24 weeks' gestation from January, 2012 through November, 2013. We classified women into mutually exclusive racial and ethnic groups: non-Hispanic black (black), Hispanic, Asian, non-Hispanic white (white), and other or unknown race. We used log-binomial regression to calculate the risk ratio (RR) and 95% confidence interval (CI) of missed or late (≥ 20 weeks' gestation) screening vs. optimally-timed screening between the different racial and ethnic groups. Results Among the 2 967 women in our study population, 971 (32.7%) had either missed or late cervical length screening. Compared to white women, black (RR: 1.3; 95% CI:1.1-1.5) and Hispanic (RR:1.2; 95% CI:1.01-1.5) women were more likely to have missed or late screening. Among women screened, black (vs. white) women were more likely to be screened late (RR: 2.2; 95% CI: 1.6-3.1). Conclusions Black and Hispanic women may be more likely to have missed or late cervical length screenings. PMID:26987873

Individual and Environmental Correlates to Quality of Life in Park Users in Colombia

PubMed Central

Camargo, Diana Marina

2017-01-01

Purpose: To explore individual and environmental correlates to quality of life (QoL) in park users in Colombia. Methods: A cross-sectional study with face-to-face interviews was conducted with 1392 park users from ten parks in Colombia. The survey included sociodemographic questions, health condition assessed with EuroQuol-5-Dimensions-5-Levels; in addition, questions about accessibility to the parks and perceptions about quality of infrastructure and green areas were asked. The Spanish version of the questionnaire EUROHIS-QOL-8 items was applied to assess QoL. Log-binomial regression models were applied for analyses. Results: Years of schooling, visits to the park with a companion, active use of the park, a maximum score for quality of trees and walking paths, and the perception of safety on the way to the park were positively associated with a better QoL (p < 0.05). Health conditions related to problems in the ability to perform activities of daily living and anxiety/depression showed negative associations. Conclusions: The present study contributes to the Latin American studies by providing information on how parks in an intermediate city may contribute to increased QoL of park users through safety in neighborhoods, social support, active use, and aesthetics, cleanliness, and care of green areas. PMID:29048373

Prevalence and predictors of sunburn among beachgoers.

PubMed

de Troya-Martín, Magdalena; de Gálvez-Aranda, María Victoria; Rivas-Ruiz, Francisco; Blázquez-Sánchez, Nuria; Fernández-Morano, Maria Teresa; Padilla-España, Laura; Herrera-Ceballos, Enrique

2018-03-01

Painful sunburns at any age are one of the main risk factors for skin cancer. To determine the prevalence and predictors of sunburn among beachgoers. A cross-sectional health survey was conducted at the beach during the summer. Adults >18 years with an understanding of Spanish were interviewed using a questionnaire about behaviours, attitudes and knowledge related to sun exposure at the beach. A descriptive analysis was performed, and a log-binomial regression model was used to determine predictors of sunburn. The survey was completed by 1054 beachgoers, with a mean age of 43.8 (SD: 18.7) years, 61.2% women, skin phototypes i (13.6%), ii (22.3%), iii (34.0%) and iv (30.2%). 46.9% of responders reported at least one painful sunburn during the previous summer. Age, sex, education, skin phototype, midday sun exposure, sun protection habits, attitudes towards tanning and knowledge about skin cancer were identified as independent predictors of sunburn. It is necessary to develop photoprotection campaigns aimed at beachgoers, particularly in young people, men, those with skin phototypes I-III and secondary or university education. Educational strategies should be aimed at discouraging sun exposure at midday, changing attitudes towards tanning and improving knowledge about skin cancer. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Attachment to employment and education before work disability pension due to a mental disorder among young adults.

PubMed

Mattila-Holappa, Pauliina; Joensuu, Matti; Ahola, Kirsi; Vahtera, Jussi; Virtanen, Marianna

2016-05-13

We examined attachment to employment and education among young adults before they were granted a fixed-term work disability pension due to psychiatric diagnosis, and the factors associated with this attachment. The data comprised all persons aged 18-34 who received a new-onset fixed-term disability pension compensation due to a mental disorder in Finland in 2008 (N = 1163). The data were derived from pension applications and the enclosed medical records, and were linked to employment records from a period of three years before the disability pension. We analysed the factors associated with attachment to employment or education with log-binomial regression analysis. Fifty percent of the participants were attached to employment or education before work disability pension. The attached were more often women; had higher basic and vocational education; had mood disorder rather than psychosis diagnosis as a primary diagnosis; and had no record of harmful alcohol use or drug use, or recorded symptoms of mental disorders already at school-age. The level of attachment to employment or education before work disability pension is low among young adults with mental disorders and several risk factors predict poor attachment; severe or comorbid mental disorder, early-life psychiatric morbidity, substance use, male sex, low basic education, and lacking vocational education.

Recall of anti-tobacco advertisements and effects on quitting behavior: results from the California smokers cohort.

PubMed

Leas, Eric C; Myers, Mark G; Strong, David R; Hofstetter, C Richard; Al-Delaimy, Wael K

2015-02-01

We assessed whether an anti-tobacco television advertisement called "Stages," which depicted a woman giving a brief emotional narrative of her experiences with tobacco use, would be recalled more often and have a greater effect on smoking cessation than 3 other advertisements with different intended themes. Our data were derived from a sample of 2596 California adult smokers. We used multivariable log-binomial and modified Poisson regression models to calculate respondents' probability of quitting as a result of advertisement recall. More respondents recalled the "Stages" ad (58.5%) than the 3 other ads (23.1%, 23.4%, and 25.6%; P<.001). Respondents who recalled "Stages" at baseline had a higher probability than those who did not recall the ad of making a quit attempt between baseline and follow-up (adjusted risk ratio [RR]=1.18; 95% confidence interval [CI]=1.03, 1.34) and a higher probability of being in a period of smoking abstinence for at least a month at follow-up (adjusted RR=1.55; 95% CI=1.02, 2.37). Anti-tobacco television advertisements that depict visceral and personal messages may be recalled by a larger percentage of smokers and may have a greater impact on smoking cessation than other types of advertisements.

Acute Rejection in Renal Transplant Patients of a Hospital in Bogota, Colombia

PubMed Central

García, P.; Huerfano, M; Rodríguez, M; Caicedo, A; Berrío, F; Gonzalez, C

2016-01-01

Background: Renal transplantation is the best treatment for end stage renal disease. Acute graft rejection is one of the main complications and may influence graft survival. Objective: To determine the incidence and features of acute cellular rejection (ACR) episodes confirmed by biopsy. Methods: We studied a cohort of 175 patients who underwent renal transplantation between 2004 and 2012 to determine the cumulative incidence of ACR confirmed by biopsy and to identify the associated risk factors using multivariate analysis. Results: The one-year patient survival was 96.6%; the graft survival was 93.7%. The incidence of ACR within one year was 14.3%, of which 46% were observed within 6 months following transplantation. The most frequently observed ACR type was 1B according to the Banff classification system (42%). A relationship between ACR and receipt of a kidney from expanded criteria donors was observed, both in univariate and adjusted multiple log-binomial regression analyses, but only 6.3% of patients received extended criteria donor kidneys. No other relationships between variables were found. Conclusion: ACR frequency in this study was similar to that of other cohorts reported previously. We need a bigger sample of renal transplants from expanded criteria donors, PRA and DSA test to support the results. PMID:27721962

Correspondence analysis to evaluate the transmission of Staphylococcus aureus strains in two New York State maximum-security prisons.

PubMed

Befus, M; Mukherjee, D V; Herzig, C T A; Lowy, F D; Larson, E

2017-07-01

Prisons/jails are thought to amplify the transmission of Staphylococcus aureus (SA) particularly methicillin-resistant SA infection and colonisation. Two independently pooled cross-sectional samples of detainees being admitted or discharged from two New York State maximum-security prisons were used to explore this concept. Private interviews of participants were conducted, during which the anterior nares and oropharynx were sampled and assessed for SA colonisation. Log-binomial regression and correspondence analysis (CA) were used to evaluate the prevalence of colonisation at entry as compared with discharge. Approximately 51% of admitted (N = 404) and 41% of discharged (N = 439) female detainees were colonised with SA. Among males, 59% of those admitted (N = 427) and 49% of those discharged (N = 393) were colonised. Females had a statistically significant higher prevalence (1·26: P = 0·003) whereas males showed no significant difference (1·06; P = 0·003) in SA prevalence between entry and discharge. CA demonstrated that some strains, such as spa types t571 and t002, might have an affinity for certain mucosal sites. Contrary to our hypothesis, the prison setting did not amplify SA transmission, and CA proved to be a useful tool in describing the population structure of strains according to time and/or mucosal site.

Psychotherapeutic and vocational interventions among young adults with work disability due to mental disorders in Finland.

PubMed

Mattila-Holappa, Pauliina; Joensuu, Matti; Ahola, Kirsi; Kivekäs, Teija; Kivimäki, Mika; Koskinen, Aki; Virtanen, Marianna

2018-05-01

Backround: Little is known about treatment and rehabilitation received and planned among young adults with work disability due to a mental disorder. To examine the implemented psychotherapeutic and vocational interventions and treatment plans among young adults with work disability due to a mental disorder. Data were collected from medical records of young Finnish adults aged 18-34 with a long-term work disability history due to a mental disorder (N = 1163). The participant characteristics associated with four types of interventions were analyzed using log-binomial regression analysis. In total, 34% had participated in a psychotherapeutic intervention. Of the non-students, 26% had participated in vocational intervention. For 46% of the non-students, neither type of intervention was planned. Both implemented and planned psychotherapeutic interventions were associated with female sex, high education, attachment to employment, and absence of substance abuse. Low education and childhood adversity were associated with implemented vocational interventions and absence of substance abuse with planned vocational interventions. There is an unmet need for psychotherapeutic interventions among men, among those with lower socio-economic status, and among those with poor attachment to labor market. In addition, there is a lack of vocational interventions for those with high education. People with substance abuse are largely excluded from both types of interventions.

Analyzing hospitalization data: potential limitations of Poisson regression.

PubMed

Weaver, Colin G; Ravani, Pietro; Oliver, Matthew J; Austin, Peter C; Quinn, Robert R

2015-08-01

Poisson regression is commonly used to analyze hospitalization data when outcomes are expressed as counts (e.g. number of days in hospital). However, data often violate the assumptions on which Poisson regression is based. More appropriate extensions of this model, while available, are rarely used. We compared hospitalization data between 206 patients treated with hemodialysis (HD) and 107 treated with peritoneal dialysis (PD) using Poisson regression and compared results from standard Poisson regression with those obtained using three other approaches for modeling count data: negative binomial (NB) regression, zero-inflated Poisson (ZIP) regression and zero-inflated negative binomial (ZINB) regression. We examined the appropriateness of each model and compared the results obtained with each approach. During a mean 1.9 years of follow-up, 183 of 313 patients (58%) were never hospitalized (indicating an excess of 'zeros'). The data also displayed overdispersion (variance greater than mean), violating another assumption of the Poisson model. Using four criteria, we determined that the NB and ZINB models performed best. According to these two models, patients treated with HD experienced similar hospitalization rates as those receiving PD {NB rate ratio (RR): 1.04 [bootstrapped 95% confidence interval (CI): 0.49-2.20]; ZINB summary RR: 1.21 (bootstrapped 95% CI 0.60-2.46)}. Poisson and ZIP models fit the data poorly and had much larger point estimates than the NB and ZINB models [Poisson RR: 1.93 (bootstrapped 95% CI 0.88-4.23); ZIP summary RR: 1.84 (bootstrapped 95% CI 0.88-3.84)]. We found substantially different results when modeling hospitalization data, depending on the approach used. Our results argue strongly for a sound model selection process and improved reporting around statistical methods used for modeling count data. © The Author 2015. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Perceived Prevalence of Teasing and Bullying Predicts High School Dropout Rates

ERIC Educational Resources Information Center

Cornell, Dewey; Gregory, Anne; Huang, Francis; Fan, Xitao

2013-01-01

This prospective study of 276 Virginia public high schools found that the prevalence of teasing and bullying (PTB) as perceived by both 9th-grade students and teachers was predictive of dropout rates for this cohort 4 years later. Negative binomial regression indicated that one standard deviation increases in student- and teacher-reported PTB were…

Assessing Trauma, Substance Abuse, and Mental Health in a Sample of Homeless Men

ERIC Educational Resources Information Center

Kim, Mimi M.; Ford, Julian D.; Howard, Daniel L.; Bradford, Daniel W.

2010-01-01

This study examined the impact of physical and sexual trauma on a sample of 239 homeless men. Study participants completed a self-administered survey that collected data on demographics, exposure to psychological trauma, physical health and mental health problems, and substance use or misuse. Binomial logistic regression analyses were used to…

Social determinants of leprosy in a hyperendemic State in North Brazil.

PubMed

Monteiro, Lorena Dias; Mota, Rosa Maria Salani; Martins-Melo, Francisco Rogerlândio; Alencar, Carlos Henrique; Heukelbach, Jorg

2017-07-20

To identify the socioeconomic, demographic, operational, and health service-related factors associated with the occurrence of leprosy in a hyperendemic State in North Brazil. This is an ecological study based on secondary data from the Sistema de Informações de Agravos de Notificação in municipalities of the State of Tocantins from 2001 to 2012. Units of analysis were the 139 municipalities of the State. Negative binomial log linear regression models were used to estimate incidence rate ratios. In bivariate analysis, the incidence rate ratios were significantly higher for municipalities with higher income ratio of the poorest 20.0% (1.47; 95%CI 1.19-1.81) and better Municipal Human Development Index (1.53; 95%CI 1.14-2.06). In multivariate analysis, the incidence rate ratios were significantly higher in municipalities with higher proportion of immigrants (1.31; 95%CI 1.11-1.55) and higher proportion of households with waste collection (1.37; 95%CI 1.11-1.69). There was a significant reduction in the incidence rate ratio with increased coverage of the Bolsa Família Program (0.98; 95%CI 0.96-0.99). Control programs need to focus on activities in municipalities of greater social vulnerability with intersectoral investment for the improvement of the living conditions of the population. Identificar fatores socioeconômicos, demográficos, operacionais e de serviços de saúde associados à ocorrência da hanseníase em um estado hiperendêmico do norte do Brasil. Estudo ecológico com dados secundários do Sistema de Informações de Agravos de Notificação em municípios do estado do Tocantins de 2001 a 2012. As unidades de análise foram os 139 municípios do estado. Modelos de regressão log linear binomial negativa foram utilizados para estimar as razões de taxas de incidência. Na análise bivariada, a razão de taxa de incidência foi significativamente maior para os municípios com maior razão de renda dos 20,0% mais pobres (1,47; IC95% 1,19-1,81) e melhor Índice de Desenvolvimento Humano Municipal (1,53; IC95% 1,14-2,06). Na múltipla, a razão de taxa de incidência foi significativamente superior em municípios com maior concentração de imigrantes (1,31; IC95% 1,11-1,55) e proporção de domicílios com coleta de lixo (1,37; IC95% 1,11-1,69). Houve redução significativa da razão de taxa de incidência com o aumento da cobertura do programa bolsa família (0,98; IC95% 0,96-0,99). Os programas de controle precisam focar as atividades em municípios de maior vulnerabilidade social com investimentos intersetoriais para a melhoria das condições de vida da população.

A statistical model to estimate the impact of a hepatitis A vaccination programme.

PubMed

Oviedo, Manuel; Pilar Muñoz, M; Domínguez, Angela; Borras, Eva; Carmona, Gloria

2008-11-11

A program of routine hepatitis A+B vaccination in preadolescents was introduced in 1998 in Catalonia, a region situated in the northeast of Spain. The objective of this study was to quantify the reduction in the incidence of hepatitis A in order to differentiate the natural reduction of the incidence of hepatitis A from that produced due to the vaccination programme and to predict the evolution of the disease in forthcoming years. A generalized linear model (GLM) using negative binomial regression was used to estimate the incidence rates of hepatitis A in Catalonia by year, age group and vaccination. Introduction of the vaccine reduced cases by 5.5 by year (p-value<0.001), but there was a significant interaction between the year of report and vaccination that smoothed this reduction (p-value<0.001). The reduction was not equal in all age groups, being greater in the 12-18 years age group, which fell from a mean rate of 8.15 per 100,000 person/years in the pre-vaccination period (1992-1998) to 1.4 in the vaccination period (1999-2005). The model predicts the evolution accurately for the group of vaccinated subjects. Negative binomial regression is more appropriate than Poisson regression when observed variance exceeds the observed mean (overdispersed count data), can cause a variable apparently contribute more on the model of what really makes it.

Seasonal variation and partitioning of endocrine disrupting chemicals in waters and sediments of the Pearl River system, South China.

PubMed

Gong, Jian; Duan, Dandan; Yang, Yu; Ran, Yong; Chen, Diyun

2016-12-01

Endocrine disrupting chemicals (EDCs) were seasonally investigated in surface water, suspended particulate matter, and sediments of the Pearl River Delta (PRD), South China. EDC concentrations in the surface water were generally higher in the summer than in winter. The surface water in the investigated rivers was heavily contaminated by the phenolic xenoestrogens. Moreover, the in-situ log K soc and log K poc values and their regression with log K ow in the field experiments suggest that binding mechanisms other than hydrophobic interaction are present for the sedimentary organic carbon and particulate organic carbon (SOC/POC). The logK soc -logK ow and logK poc -logK ow regression analyses imply that higher complexity of nonhydrophobic interactions with EDCs is present on the SOC samples comparing with the POC samples, which is related to their different sources. Copyright © 2016 Elsevier Ltd. All rights reserved.

Estimation of the cure rate in Iranian breast cancer patients.

PubMed

Rahimzadeh, Mitra; Baghestani, Ahmad Reza; Gohari, Mahmood Reza; Pourhoseingholi, Mohamad Amin

2014-01-01

Although the Cox's proportional hazard model is the popular approach for survival analysis to investigate significant risk factors of cancer patient survival, it is not appropriate in the case of log-term disease free survival. Recently, cure rate models have been introduced to distinguish between clinical determinants of cure and variables associated with the time to event of interest. The aim of this study was to use a cure rate model to determine the clinical associated factors for cure rates of patients with breast cancer (BC). This prospective cohort study covered 305 patients with BC, admitted at Shahid Faiazbakhsh Hospital, Tehran, during 2006 to 2008 and followed until April 2012. Cases of patient death were confirmed by telephone contact. For data analysis, a non-mixed cure rate model with Poisson distribution and negative binomial distribution were employed. All analyses were carried out using a developed Macro in WinBugs. Deviance information criteria (DIC) were employed to find the best model. The overall 1-year, 3-year and 5-year relative survival rates were 97%, 89% and 74%. Metastasis and stage of BC were the significant factors, but age was significant only in negative binomial model. The DIC also showed that the negative binomial model had a better fit. This study indicated that, metastasis and stage of BC were identified as the clinical criteria for cure rates. There are limited studies on BC survival which employed these cure rate models to identify the clinical factors associated with cure. These models are better than Cox, in the case of long-term survival.

Accounting for measurement error in log regression models with applications to accelerated testing.

PubMed

Richardson, Robert; Tolley, H Dennis; Evenson, William E; Lunt, Barry M

2018-01-01

In regression settings, parameter estimates will be biased when the explanatory variables are measured with error. This bias can significantly affect modeling goals. In particular, accelerated lifetime testing involves an extrapolation of the fitted model, and a small amount of bias in parameter estimates may result in a significant increase in the bias of the extrapolated predictions. Additionally, bias may arise when the stochastic component of a log regression model is assumed to be multiplicative when the actual underlying stochastic component is additive. To account for these possible sources of bias, a log regression model with measurement error and additive error is approximated by a weighted regression model which can be estimated using Iteratively Re-weighted Least Squares. Using the reduced Eyring equation in an accelerated testing setting, the model is compared to previously accepted approaches to modeling accelerated testing data with both simulations and real data.

Comparison of Survival Models for Analyzing Prognostic Factors in Gastric Cancer Patients

PubMed

Habibi, Danial; Rafiei, Mohammad; Chehrei, Ali; Shayan, Zahra; Tafaqodi, Soheil

2018-03-27

Objective: There are a number of models for determining risk factors for survival of patients with gastric cancer. This study was conducted to select the model showing the best fit with available data. Methods: Cox regression and parametric models (Exponential, Weibull, Gompertz, Log normal, Log logistic and Generalized Gamma) were utilized in unadjusted and adjusted forms to detect factors influencing mortality of patients. Comparisons were made with Akaike Information Criterion (AIC) by using STATA 13 and R 3.1.3 softwares. Results: The results of this study indicated that all parametric models outperform the Cox regression model. The Log normal, Log logistic and Generalized Gamma provided the best performance in terms of AIC values (179.2, 179.4 and 181.1, respectively). On unadjusted analysis, the results of the Cox regression and parametric models indicated stage, grade, largest diameter of metastatic nest, largest diameter of LM, number of involved lymph nodes and the largest ratio of metastatic nests to lymph nodes, to be variables influencing the survival of patients with gastric cancer. On adjusted analysis, according to the best model (log normal), grade was found as the significant variable. Conclusion: The results suggested that all parametric models outperform the Cox model. The log normal model provides the best fit and is a good substitute for Cox regression. Creative Commons Attribution License

Regular exercise and related factors in patients with Parkinson's disease: Applying zero-inflated negative binomial modeling of exercise count data.

PubMed

Lee, JuHee; Park, Chang Gi; Choi, Moonki

2016-05-01

This study was conducted to identify risk factors that influence regular exercise among patients with Parkinson's disease in Korea. Parkinson's disease is prevalent in the elderly, and may lead to a sedentary lifestyle. Exercise can enhance physical and psychological health. However, patients with Parkinson's disease are less likely to exercise than are other populations due to physical disability. A secondary data analysis and cross-sectional descriptive study were conducted. A convenience sample of 106 patients with Parkinson's disease was recruited at an outpatient neurology clinic of a tertiary hospital in Korea. Demographic characteristics, disease-related characteristics (including disease duration and motor symptoms), self-efficacy for exercise, balance, and exercise level were investigated. Negative binomial regression and zero-inflated negative binomial regression for exercise count data were utilized to determine factors involved in exercise. The mean age of participants was 65.85 ± 8.77 years, and the mean duration of Parkinson's disease was 7.23 ± 6.02 years. Most participants indicated that they engaged in regular exercise (80.19%). Approximately half of participants exercised at least 5 days per week for 30 min, as recommended (51.9%). Motor symptoms were a significant predictor of exercise in the count model, and self-efficacy for exercise was a significant predictor of exercise in the zero model. Severity of motor symptoms was related to frequency of exercise. Self-efficacy contributed to the probability of exercise. Symptom management and improvement of self-efficacy for exercise are important to encourage regular exercise in patients with Parkinson's disease. Copyright © 2015 Elsevier Inc. All rights reserved.

Stability of a Model Explaining Selected Extramusical Influences on Solo and Small-Ensemble Festival Ratings

ERIC Educational Resources Information Center

Bergee, Martin J.; Westfall, Claude R.

2005-01-01

This is the third study in a line of inquiry whose purpose has been to develop a theoretical model of selected extra musical variables' influence on solo and small-ensemble festival ratings. Authors of the second of these (Bergee & McWhirter, 2005) had used binomial logistic regression as the basis for their model-formulation strategy. Their…

A Negative Binomial Regression Model for Accuracy Tests

ERIC Educational Resources Information Center

Hung, Lai-Fa

2012-01-01

Rasch used a Poisson model to analyze errors and speed in reading tests. An important property of the Poisson distribution is that the mean and variance are equal. However, in social science research, it is very common for the variance to be greater than the mean (i.e., the data are overdispersed). This study embeds the Rasch model within an…

Which Types of Televised Anti-Tobacco Campaigns Prompt More Quitline Calls from Disadvantaged Groups?

ERIC Educational Resources Information Center

Durkin, Sarah J.; Wakefield, Melanie A.; Spittal, Matthew J.

2011-01-01

To examine the efficacy of different types of mass media ads in driving lower socio-economic smokers (SES) to utilize quitlines. This study collected all 33 719 calls to the Victorian quitline in Australia over a 2-year period. Negative binomial regressions examined the relationship between weekly levels of exposure to different types of…

A Time Series Analysis: Weather Factors, Human Migration and Malaria Cases in Endemic Area of Purworejo, Indonesia, 2005–2014

PubMed Central

REJEKI, Dwi Sarwani Sri; NURHAYATI, Nunung; AJI, Budi; MURHANDARWATI, E. Elsa Herdiana; KUSNANTO, Hari

2018-01-01

Background: Climatic and weather factors become important determinants of vector-borne diseases transmission like malaria. This study aimed to prove relationships between weather factors with considering human migration and previous case findings and malaria cases in endemic areas in Purworejo during 2005–2014. Methods: This study employed ecological time series analysis by using monthly data. The independent variables were the maximum temperature, minimum temperature, maximum humidity, minimum humidity, precipitation, human migration, and previous malaria cases, while the dependent variable was positive malaria cases. Three models of count data regression analysis i.e. Poisson model, quasi-Poisson model, and negative binomial model were applied to measure the relationship. The least Akaike Information Criteria (AIC) value was also performed to find the best model. Negative binomial regression analysis was considered as the best model. Results: The model showed that humidity (lag 2), precipitation (lag 3), precipitation (lag 12), migration (lag1) and previous malaria cases (lag 12) had a significant relationship with malaria cases. Conclusion: Weather, migration and previous malaria cases factors need to be considered as prominent indicators for the increase of malaria case projection. PMID:29900134

Alternative Regression Equations for Estimation of Annual Peak-Streamflow Frequency for Undeveloped Watersheds in Texas using PRESS Minimization

USGS Publications Warehouse

Asquith, William H.; Thompson, David B.

2008-01-01

The U.S. Geological Survey, in cooperation with the Texas Department of Transportation and in partnership with Texas Tech University, investigated a refinement of the regional regression method and developed alternative equations for estimation of peak-streamflow frequency for undeveloped watersheds in Texas. A common model for estimation of peak-streamflow frequency is based on the regional regression method. The current (2008) regional regression equations for 11 regions of Texas are based on log10 transformations of all regression variables (drainage area, main-channel slope, and watershed shape). Exclusive use of log10-transformation does not fully linearize the relations between the variables. As a result, some systematic bias remains in the current equations. The bias results in overestimation of peak streamflow for both the smallest and largest watersheds. The bias increases with increasing recurrence interval. The primary source of the bias is the discernible curvilinear relation in log10 space between peak streamflow and drainage area. Bias is demonstrated by selected residual plots with superimposed LOWESS trend lines. To address the bias, a statistical framework based on minimization of the PRESS statistic through power transformation of drainage area is described and implemented, and the resulting regression equations are reported. Compared to log10-exclusive equations, the equations derived from PRESS minimization have PRESS statistics and residual standard errors less than the log10 exclusive equations. Selected residual plots for the PRESS-minimized equations are presented to demonstrate that systematic bias in regional regression equations for peak-streamflow frequency estimation in Texas can be reduced. Because the overall error is similar to the error associated with previous equations and because the bias is reduced, the PRESS-minimized equations reported here provide alternative equations for peak-streamflow frequency estimation.

Economic independence in survivors of cancer diagnosed at a young age: A Norwegian national cohort study.

PubMed

Gunnes, Maria W; Lie, Rolv Terje; Bjørge, Tone; Syse, Astri; Ruud, Ellen; Wesenberg, Finn; Moster, Dag

2016-12-15

The impact of cancer on socioeconomic outcomes is attracting attention as the number of survivors of cancer in young age continues to rise. This study examines economic independence in a national cohort of survivors of cancer at a young age in Norway. Through the linkage of several national registries, the study cohort comprised 1,212,013 individuals born in Norway during 1965 through 1985, of which 5440 had received a cancer diagnosis before age 25 years. Follow-up was through 2007, and the main outcomes were receipt of governmental financial assistance, employment, income, and occupation. Analytic methods included Cox proportional hazard regression, log-binomial regression, and quantile regression models. Individuals in the cancer survivor group had an increased probability of receiving governmental financial assistance (men: hazard ratio [HR], 1.4; 95% confidence interval [CI], 1.3-1.5; women: HR, 1.5; 95% CI, 1.3-1.6) and of not being employed (men: HR, 1.4; 95% CI, 1.2-1.7; women: HR, 1.4; 95% CI, 1.2-1.6) compared with those in the noncancer group. Income discrepancies were particularly pronounced for survivors of central nervous system tumors. There was no difference in representation in higher skilled occupations. Survivors of cancer at a young age in Norway had an increased risk of being economically dependent and unemployed. This was evident in several tumor groups and was most pronounced in female survivors. There were only small differences in income or representation in higher skilled occupations for most employed survivors compared with the noncancer group. The current results are important for understanding the impact of a cancer diagnosis at a young age on subsequent job market outcomes. Cancer 2016;122:3873-3882. © 2016 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. © 2016 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.

Estimation of octanol/water partition coefficients using LSER parameters

USGS Publications Warehouse

Luehrs, Dean C.; Hickey, James P.; Godbole, Kalpana A.; Rogers, Tony N.

1998-01-01

The logarithms of octanol/water partition coefficients, logKow, were regressed against the linear solvation energy relationship (LSER) parameters for a training set of 981 diverse organic chemicals. The standard deviation for logKow was 0.49. The regression equation was then used to estimate logKow for a test of 146 chemicals which included pesticides and other diverse polyfunctional compounds. Thus the octanol/water partition coefficient may be estimated by LSER parameters without elaborate software but only moderate accuracy should be expected.

Inference for binomial probability based on dependent Bernoulli random variables with applications to meta-analysis and group level studies.

PubMed

Bakbergenuly, Ilyas; Kulinskaya, Elena; Morgenthaler, Stephan

2016-07-01

We study bias arising as a result of nonlinear transformations of random variables in random or mixed effects models and its effect on inference in group-level studies or in meta-analysis. The findings are illustrated on the example of overdispersed binomial distributions, where we demonstrate considerable biases arising from standard log-odds and arcsine transformations of the estimated probability p̂, both for single-group studies and in combining results from several groups or studies in meta-analysis. Our simulations confirm that these biases are linear in ρ, for small values of ρ, the intracluster correlation coefficient. These biases do not depend on the sample sizes or the number of studies K in a meta-analysis and result in abysmal coverage of the combined effect for large K. We also propose bias-correction for the arcsine transformation. Our simulations demonstrate that this bias-correction works well for small values of the intraclass correlation. The methods are applied to two examples of meta-analyses of prevalence. © 2016 The Authors. Biometrical Journal Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Dental enamel defects predict adolescent health indicators: A cohort study among the Tsimane' of Bolivia.

PubMed

Masterson, Erin E; Fitzpatrick, Annette L; Enquobahrie, Daniel A; Mancl, Lloyd A; Eisenberg, Dan T A; Conde, Esther; Hujoel, Philippe P

2018-05-01

Bioarchaeological findings have linked defective enamel formation in preadulthood with adult mortality. We investigated how defective enamel formation in infancy and childhood is associated with risk factors for adult morbidity and mortality in adolescents. This cohort study of 349 Amerindian adolescents (10-17 years of age) related extent of enamel defects on the central maxillary incisors (none, less than 1/3, 1/3 to 2/3, more than 2/3) to adolescent anthropometrics (height, weight) and biomarkers (hemoglobin, glycated hemoglobin, white blood cell count, and blood pressure). Risk differences and 95% confidence intervals were estimated using multiple linear regression. Enamel defects and stunted growth were compared in their ability to predict adolescent health indicators using log-binomial regression and receiver operating characteristics (ROCs). Greater extent of defective enamel formation on the tooth surface was associated with shorter height (-1.35 cm, 95% CI: -2.17, -0.53), lower weight (-0.98 kg, 95% CI: -1.70, -0.26), lower hemoglobin (-0.36 g/dL, 95% CI: -0.59, -0.13), lower glycated hemoglobin (-0.04 %A 1c , 95% CI: -0.08, -0.00008), and higher white blood cell count (0.74 10 9 /L, 95% CI: 0.35, 1.14) in adolescence. Extent of enamel defects and stunted growth independently performed similarly as risk factors for adverse adolescent outcomes, including anemia, prediabetes/type II diabetes, elevated WBC count, prehypertension/hypertension, and metabolic health. Defective enamel formation in infancy and childhood predicted adolescent health outcomes and may be primarily associated with infection. Extent of enamel defects and stunted growth may be equally predictive of adverse adolescent health outcomes. © 2018 Wiley Periodicals, Inc.

Reactivation of Herpes Simplex Virus Type 2 After Initiation of Antiretroviral Therapy

PubMed Central

Tobian, Aaron A. R.; Grabowski, Mary K.; Serwadda, David; Newell, Kevin; Ssebbowa, Paschal; Franco, Veronica; Nalugoda, Fred; Wawer, Maria J.; Gray, Ronald H.; Quinn, Thomas C.; Reynolds, Steven J.

2013-01-01

Background. The association between initiation of antiretroviral therapy (ART) for human immunodeficiency virus (HIV) infection and possible herpes simplex virus type 2 (HSV-2) shedding and genital ulcer disease (GUD) has not been evaluated. Methods. GUD and vaginal HSV-2 shedding were evaluated among women coinfected with HIV and HSV-2 (n = 440 for GUD and n = 96 for HSV-2 shedding) who began ART while enrolled in a placebo-controlled trial of HSV-2 suppression with acyclovir in Rakai, Uganda. Monthly vaginal swabs were tested for HSV-2 shedding, using a real-time quantitative polymerase chain reaction assay. Prevalence risk ratios (PRRs) of GUD were estimated using log binomial regression. Random effects logistic regression was used to estimate odds ratios (ORs) of HSV-2 shedding. Results. Compared with pre-ART values, GUD prevalence increased significantly within the first 3 months after ART initiation (adjusted PRR, 1.94; 95% confidence interval [CI], 1.04–3.62) and returned to baseline after 6 months of ART (adjusted PRR, 0.80; 95% CI, .35–1.80). Detection of HSV-2 shedding was highest in the first 3 months after ART initiation (adjusted OR, 2.58; 95% CI, 1.48–4.49). HSV-2 shedding was significantly less common among women receiving acyclovir (adjusted OR, 0.13; 95% CI, .04–.41). Conclusions. The prevalence of HSV-2 shedding and GUD increased significantly after ART initiation, possibly because of immune reconstitution inflammatory syndrome. Acyclovir significantly reduced both GUD and HSV-2 shedding and should be considered to mitigate these effects following ART initiation. PMID:23812240

Angiogenic and inflammatory biomarkers in mid-pregnancy and small-for-gestational age outcomes in Tanzania

PubMed Central

DARLING, Anne Marie; MCDONALD, Chloe R.; CONROY, Andrea L.; HAYFORD, Kyla T.; RAJWANS, Nimerta; WANG, Molin; ABOUD, Said; URASSA, Willy S.; KAIN, Kevin C.; FAWZI, Wafaie W.

2014-01-01

OBJECTIVE To investigate the relationship between a panel of angiogenic and inflammatory biomarkers measured in mid-pregnancy and small-for-gestational age (SGA) outcomes in sub-Saharan Africa. STUDY DESIGN Concentrations of 18 angiogenic and inflammatory biomarkers were determined in 432 pregnant women in Dar es Salaam, Tanzania who participated in a trial examining the effect of multivitamins on pregnancy outcomes. Infants falling below the 10th percentile of birth weight for gestational age relative to the applied growth standards were considered SGA. Multivariate binomial regression models with the log link function were used to determine the relative risk of SGA associated with increasing quartiles of each biomarker. Stepwise cubic restricted splines were used to test for non-linearity of these associations. Receiver operating curves obtained from multivariate logistic regression models were used to assess the discriminatory capability of selected biomarkers. RESULTS A total of 60 participants (13.9%) gave birth to SGA infants. Compared to those in the first quartile, the risk of SGA was reduced among those in the fourth quartiles of VEGF-A (adjusted risk ratio (RR) 0.38, 95% Confidence Interval (CI), 0.19-0.74), PGF (adjusted RR 0.28, 95% CI, 0.12-0.61), sFlt-1 (adjusted RR 0.48, 95% CI, 0.23-1.01), MCP-1 (adjusted RR 0.48, 95% CI, 0.25-0.92), and Leptin (adjusted RR 0.46, 95% CI, 0.22-0.96) CONCLUSION Our findings provide evidence of altered angiogenic and inflammatory mediators, at mid-pregnancy, in women who went on to deliver small for gestational age infants. PMID:24881826

U.S. military service and the prevalence of metabolic syndrome: Findings from a cross-sectional analysis of the Cooper Center Longitudinal Study, 1979-2013.

PubMed

Janak, Jud C; Pérez, Adriana; Alamgir, Hasanat; Orman, Jean A; Cooper, Sharon P; Shuval, Kerem; DeFina, Laura; Barlow, Carolyn E; Gabriel, Kelley Pettee

2017-02-01

U.S. military service confers both health benefits and risks potentially associated with a clustering of cardiovascular risk factors called metabolic syndrome. However, the association between prior military service and metabolic syndrome has not sufficiently been examined. The purpose of the study was to compare the prevalence of metabolic syndrome by prior military service status. Among 42,370 men (887 with prior military service) examined from 1979 to 2013 at the Cooper Clinic (Dallas, TX), we used a cross-sectional study design to examine the association between military service and metabolic syndrome. First, an unadjusted log binomial regression model was performed by regressing the prevalence of metabolic syndrome on prior service. This was followed by performing Kleinbaum's modeling strategy for assessing confounding. The same methodology was used to explore the association between individual metabolic syndrome risk factors and prior service. Prior military service was not significantly associated with the prevalence of metabolic syndrome (PR=0.98, 0.89-1.07). None of the variables explored were identified as confounders. Participants with prior military service had lower prevalence of both elevated levels of triglycerides (PR=0.89, 0.80-0.99) and low levels of high-density lipoprotein-cholesterol (PR=0.78, 0.70-0.88). They had a higher prevalence of elevated resting systolic blood pressure (PR=1.23, 1.12-1.35). However, none of these associations were significant after adjusting for identified confounders: age; cardiorespiratory fitness; and exam year. Study findings indicate that military service was not independently associated with the prevalence of metabolic syndrome or its components. Future research is warranted longitudinally assessing the impact of military service on long-term outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

High Rates of Exclusive Breastfeeding in Both Arms of a Peer Counseling Study Promoting EBF Among HIV-Infected Kenyan Women.

PubMed

Bosire, Rose; Betz, Bourke; Aluisio, Adam; Hughes, James P; Nduati, Ruth; Kiarie, James; Chohan, Bhavna H; Merkel, Michele; Lohman-Payne, Barbara; John-Stewart, Grace; Farquhar, Carey

2016-03-01

Exclusive breastfeeding (EBF) is recommended for 6 months after delivery as the optimal infant feeding method and is especially important for prevention of mother-to-child HIV transmission (PMTCT). However, EBF promotion efforts among HIV-infected mothers in sub-Saharan Africa have achieved mixed success and require context-specific interventions. HIV-positive, pregnant women from six clinics in Nairobi were enrolled into a clinic-level, before-after counseling intervention study. All women received standard perinatal and HIV care. Women in the intervention arm were offered three counseling sessions that promoted EBF, described its benefits, and explained breastfeeding techniques. Mother-infant pairs were followed until 14 weeks postpartum, with infant HIV testing at 6 weeks. EBF prevalence at 14 weeks postpartum was compared between study arms using log-binomial regression. Proportions of 6-week HIV-free survival and 14-week infant survival were assessed using Cox regression. Risk estimates were adjusted for clinic, relationship status, and antiretroviral therapy. Between 2009 and 2013, 833 women were enrolled of whom 94% planned to practice EBF for 6 months and 95% were taking therapeutic or prophylactic antiretrovirals. Median age was 27 years; median CD4 count was 403 cells/μL. EBF prevalence at 14 weeks postpartum was 86% in the control and 81% in the intervention group (p = 0.19). No differences were observed between groups for 6-week HIV-free survival and 14-week infant survival. Women who received breastfeeding counseling were not more likely to breastfeed exclusively, in part due to high overall EBF prevalence in this study population. The high EBF prevalence is an important finding, given recent efforts to promote EBF in Kenya.

A comparison of resource utilization following chemotherapy for acute myeloid leukemia in children discharged versus children that remain hospitalized during neutropenia

PubMed Central

Getz, Kelly D; Miller, Tamara P; Seif, Alix E; Li, Yimei; Huang, Yuan-Shung; Bagatell, Rochelle; Fisher, Brian T; Aplenc, Richard

2015-01-01

Comparisons of early discharge and outpatient postchemotherapy supportive care in pediatric acute myeloid leukemia (AML) patients are limited. We used data from the Pediatric Health Information System on a cohort of children treated for newly diagnosed AML to compare course-specific mortality and resource utilization in patients who were discharged after chemotherapy to outpatient management during neutropenia relative to patients who remained hospitalized. Patients were categorized at each course as early or standard discharge. Discharges within 3 days after chemotherapy completion were considered “early”. Resource utilization was determined based on daily billing data and reported as days of use per 1000 hospital days. Inpatient mortality, occurrence of intensive care unit (ICU)-level care, and duration of hospitalization were compared using logistic, log-binomial and linear regression methods, respectively. Poisson regression with inpatient days as offset was used to compare resource use by discharge status. The study population included 996 patients contributing 2358 treatment courses. Fewer patients were discharged early following Induction I (7%) than subsequent courses (22–24%). Across courses, patients discharged early experienced high readmission rates (69–84%), yet 9–12 fewer inpatient days (all P < 0.001). Inpatient mortality was low across courses and did not differ significantly by discharge status. The overall risk for ICU-level care was 116% higher for early compared to standard discharge patients (adjusted risk ratio: 2.16, 95% confidence interval: 1.50, 3.11). Rates of antibiotic, vasopressor, and supplemental oxygen use were consistently elevated for early discharge patients. Despite similar inpatient mortality to standard discharge patients, early discharge patients may be at greater risk for life-threatening chemotherapy-related complications, including infections. PMID:26105201

The influence of marital status on the stage at diagnosis, treatment, and survival of adult patients with gastric cancer: a population-based study.

PubMed

Zhang, Jieyun; Gan, Lu; Wu, Zhenhua; Yan, Shican; Liu, Xiyu; Guo, Weijian

2017-04-04

Marital status was reported as a prognostic factor in many cancers. However, its role in gastric cancer (GC) hasn't been thoroughly explored. In this study, we aimed to investigate the effect of marital status on survival, stage, treatment, and survival in subgroups. We used the Surveillance, Epidemiology and End Results (SEER) database and identified 16910 GC patients. These patients were categorized into married (58.44%) and unmarred (41.56%) groups. Pearson chi-square, Wilcoxon-Mann-Whitney, Log-rank, multivariate Cox regression, univariate and multivariate binomial or multinomial logistic regression analysis were used in our analysis. Subgroup analyses of married versus unmarried patients were summarized in a forest plot. Married patients had better 5-year overall survival (OS) (32.09% VS 24.61%, P<0.001) and 5-year cancer-caused special survival (CSS) (37.74% VS 32.79%, P<0.001) than unmarried ones. Then we studied several underlying mechanisms. Firstly, married patients weren't in earlier stage at diagnosis (P=0.159). Secondly, married patients were more likely to receive surgery (P < 0.001) or radiotherapy (P < 0.001) compared with the unmarried. Thirdly, in subgroup analyses, married patients still had survival advantage in subgroups with stage II-IV and no radiotherapy. These results showed that marital status was an independently prognostic factor for both OS and CSS in GC patients. Undertreatment and lack of social support in unmarried patients were potential explanations. With the knowledge of heterogeneous effects of marriage in subgroups, we can target unmarried patients with better social support, especially who are diagnosed at late stage and undergo no treatment.

The influence of marital status on the stage at diagnosis, treatment, and survival of adult patients with gastric cancer: a population-based study

PubMed Central

Yan, Shican; Liu, Xiyu; Guo, Weijian

2017-01-01

Background & Aims Marital status was reported as a prognostic factor in many cancers. However, its role in gastric cancer (GC) hasn't been thoroughly explored. In this study, we aimed to investigate the effect of marital status on survival, stage, treatment, and survival in subgroups. Methods We used the Surveillance, Epidemiology and End Results (SEER) database and identified 16910 GC patients. These patients were categorized into married (58.44%) and unmarred (41.56%) groups. Pearson chi-square, Wilcoxon-Mann-Whitney, Log-rank, multivariate Cox regression, univariate and multivariate binomial or multinomial logistic regression analysis were used in our analysis. Subgroup analyses of married versus unmarried patients were summarized in a forest plot. Results Married patients had better 5-year overall survival (OS) (32.09% VS 24.61%, P<0.001) and 5-year cancer-caused special survival (CSS) (37.74% VS 32.79%, P<0.001) than unmarried ones. Then we studied several underlying mechanisms. Firstly, married patients weren't in earlier stage at diagnosis (P=0.159). Secondly, married patients were more likely to receive surgery (P < 0.001) or radiotherapy (P < 0.001) compared with the unmarried. Thirdly, in subgroup analyses, married patients still had survival advantage in subgroups with stage II-IV and no radiotherapy. Conclusions These results showed that marital status was an independently prognostic factor for both OS and CSS in GC patients. Undertreatment and lack of social support in unmarried patients were potential explanations. With the knowledge of heterogeneous effects of marriage in subgroups, we can target unmarried patients with better social support, especially who are diagnosed at late stage and undergo no treatment. PMID:26894860

Trends and Regional Variation in Hospital Mortality, Length of Stay and Cost in Hospital of Ischemic Stroke Patients in Alberta Accompanying the Provincial Reorganization of Stroke Care.

PubMed

Ohinmaa, Arto; Zheng, Yufei; Jeerakathil, Thomas; Klarenbach, Scott; Häkkinen, Unto; Nguyen, Thanh; Friesen, Dan; Ruseski, Jane; Kaul, Padma; Ariste, Ruolz; Jacobs, Philip

2016-12-01

This study aimed to evaluate the trends and regional variation of stroke hospital care in 30-day in-hospital mortality, hospital length of stay (LOS), and 1-year total hospitalization cost after implementation of the Alberta Provincial Stroke Strategy. New ischemic stroke patients (N = 7632) admitted to Alberta acute care hospitals between 2006 and 2011 were followed for 1 year. We analyzed in-hospital mortality with logistic regression, LOS with negative binomial regression, and the hospital costs with generalized gamma model (log link). The risk-adjusted results were compared over years and between zones using observed/expected results. The risk-adjusted mortality rates decreased from 12.6% in 2006/2007 to 9.9% in 2010/2011. The regional variations in mortality decreased from 8.3% units in 2008/2009 to 5.6 in 2010/2011. The LOS of the first episode dropped significantly in 2010/2011 after a 4-year slight increase. The regional variation in LOS was 15.5 days in 2006/2007 and decreased to 10.9 days in 2010/2011. The 1-year hospitalization cost increased initially, and then kept on declining during the last 3 years. The South and Calgary zones had the lowest costs over the study period. However, this gap was diminishing. After implementation of the Alberta Provincial Stroke Strategy, both mortality and hospital costs demonstrated a decreasing trend during the later years of study. The LOS increased slightly during the first 4 years but had a significant drop at the last year. In general, the regional variations in all 3 indicators had a diminishing trend. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

National Trends in Emergency Room Visits of Dialysis Patients for Adverse Drug Reactions.

PubMed

Chan, Lili; Saha, Aparna; Poojary, Priti; Chauhan, Kinsuk; Naik, Nidhi; Coca, Steven; Garimella, Pranav S; Nadkarni, Girish N

2018-06-12

Various medications are cleared by the kidneys, therefore patients with impaired renal function, especially dialysis patients are at risk for adverse drug events (ADEs). There are limited studies on ADEs in maintenance dialysis patients. We utilized a nationally representative database, the Nationwide Emergency Department Sample, from 2008 to 2013, to compare emergency department (ED) visits for dialysis and propensity matched non-dialysis patients. Log binomial regression was used to calculate relative risk of hospital admission and logistic regression to calculate ORs for in-hospital mortality while adjusting for patient and hospital characteristics. While ED visits for ADEs decreased in both groups, they were over 10-fold higher in dialysis patients than non-dialysis patients (65.8-88.5 per 1,000 patients vs. 4.6-5.4 per 1,000 patients respectively, p < 0.001). The top medication category associated with ED visits for ADEs in dialysis patients is agents primarily affecting blood constituents, which has increased. After propensity matching, patient admission was higher in dialysis patients than non-dialysis patients, (88 vs. 76%, p < 0.001). Dialysis was associated with a 3% increase in risk of admission and 3 times the odds of in-hospital mortality (adjusted OR 3, 95% CI 2.7-2.3.3). ED visits for ADEs are substantially higher in dialysis patients than non-dialysis patients. In dialysis patients, ADEs associated with agents primarily affecting blood constituents are on the rise. ED visits for ADEs in dialysis patients have higher inpatient admissions and in-hospital mortality. Further studies are needed to identify and implement measures aimed at reducing ADEs in dialysis patients. © 2018 S. Karger AG, Basel.

Weighted log-linear models for service delivery points in Ethiopia: a case of modern contraceptive users at health facilities.

PubMed

Workie, Demeke Lakew; Zike, Dereje Tesfaye; Fenta, Haile Mekonnen; Mekonnen, Mulusew Admasu

2018-05-10

Ethiopia is among countries with low contraceptive usage prevalence rate and resulted in high total fertility rate and unwanted pregnancy which intern affects the maternal and child health status. This study aimed to investigate the major factors that affect the number of modern contraceptive users at service delivery point in Ethiopia. The Performance Monitoring and Accountability2020/Ethiopia data collected between March and April 2016 at round-4 from 461 eligible service delivery points were in this study. The weighted log-linear negative binomial model applied to analyze the service delivery point's data. Fifty percent of service delivery points in Ethiopia given service for 61 modern contraceptive users with the interquartile range of 0.62. The expected log number of modern contraceptive users at rural was 1.05 (95% Wald CI: - 1.42 to - 0.68) lower than the expected log number of modern contraceptive users at urban. In addition, the expected log count of modern contraceptive users at others facility type was 0.58 lower than the expected log count of modern contraceptive users at the health center. The numbers of nurses/midwives were affecting the number of modern contraceptive users. Since, the incidence rate of modern contraceptive users increased by one due to an additional nurse in the delivery point. Among different factors considered in this study, residence, region, facility type, the number of days per week family planning offered, the number of nurses/midwives and number of medical assistants were to be associated with the number of modern contraceptive users. Thus, the Government of Ethiopia would take immediate steps to address causes of the number of modern contraceptive users in Ethiopia.

Some considerations for excess zeroes in substance abuse research.

PubMed

Bandyopadhyay, Dipankar; DeSantis, Stacia M; Korte, Jeffrey E; Brady, Kathleen T

2011-09-01

Count data collected in substance abuse research often come with an excess of "zeroes," which are typically handled using zero-inflated regression models. However, there is a need to consider the design aspects of those studies before using such a statistical model to ascertain the sources of zeroes. We sought to illustrate hurdle models as alternatives to zero-inflated models to validate a two-stage decision-making process in situations of "excess zeroes." We use data from a study of 45 cocaine-dependent subjects where the primary scientific question was to evaluate whether study participation influences drug-seeking behavior. The outcome, "the frequency (count) of cocaine use days per week," is bounded (ranging from 0 to 7). We fit and compare binomial, Poisson, negative binomial, and the hurdle version of these models to study the effect of gender, age, time, and study participation on cocaine use. The hurdle binomial model provides the best fit. Gender and time are not predictive of use. Higher odds of use versus no use are associated with age; however once use is experienced, odds of further use decrease with increase in age. Participation was associated with higher odds of no-cocaine use; once there is use, participation reduced the odds of further use. Age and study participation are significantly predictive of cocaine-use behavior. The two-stage decision process as modeled by a hurdle binomial model (appropriate for bounded count data with excess zeroes) provides interesting insights into the study of covariate effects on count responses of substance use, when all enrolled subjects are believed to be "at-risk" of use.

Minimizing bias in biomass allometry: Model selection and log transformation of data

Treesearch

Joseph Mascaro; undefined undefined; Flint Hughes; Amanda Uowolo; Stefan A. Schnitzer

2011-01-01

Nonlinear regression is increasingly used to develop allometric equations for forest biomass estimation (i.e., as opposed to the raditional approach of log-transformation followed by linear regression). Most statistical software packages, however, assume additive errors by default, violating a key assumption of allometric theory and possibly producing spurious models....

Do Barriers to Crime Prevention Moderate the Effects of Situational Crime Prevention Policies on Violent Crime in High Schools?

ERIC Educational Resources Information Center

Sevigny, Eric L.; Zhang, Gary

2018-01-01

This study investigates how barriers to school-based crime prevention programming moderate the effects of situational crime prevention (SCP) policies on levels of violent crime in U.S. public high schools. Using data from the 2008 School Survey on Crime and Safety, we estimate a series of negative binomial regression models with interactions to…

Relationship between suicide rate and economic growth and stock market in the People's Republic of China: 2004-2013.

PubMed

Yin, Honglei; Xu, Lin; Shao, Yechang; Li, Liping; Wan, Chengsong

2016-01-01

The objective of this study was to estimate the features of suicide rate and its association with economic development and stock market during the past decade in the People's Republic of China. Official data were gathered and analyzed in the People's Republic of China during the period 2004-2013. Nationwide suicide rate was stratified by four year age-groups, sex, urban/rural areas, and regions (East, Central, and West). Annual economic indexes including gross domestic product (GDP) per capita and rural and urban income per capita were all adjusted for inflation. Variation coefficient of market index (VCMI) was also included as an economic index to measure the fluctuation of the stock market. Negative binomial regression was performed to examine the time trend of region-level suicide rates and effects of sex, age, urban/rural area, region, and economic index on the suicide rates. Suicide rates of each age-group, sex, urban/rural area, and region were generally decreased from 2004 to 2013, while annual GDP per capita and rural and urban income per capita were generally increased by year. VCMI fluctuated largely, which peaked around 2009 and decreased after that time. Negative binomial regression showed that the decreased suicide rate in East and Central rural areas was the main cause of the decrease in suicide rate in the People's Republic of China. Suicide rate in the People's Republic of China for the study period increased with age and was higher in rural than in urban area, higher in males than in females, and the highest in the Central region. When GDP per capita increased by 2,787 RMB, the suicide rate decreased by 0.498 times. VCMI showed no significant relationship with suicide rate in the negative binomial regression. Suicide rate decreased in 2004-2013; varied among different age-groups, sex, urban/rural areas, and regions; and was negatively associated with the economic growth in the People's Republic of China. Stock market showed no relationship with suicide rate, but this finding needs to be verified in a future study.

Relationship between suicide rate and economic growth and stock market in the People’s Republic of China: 2004–2013

PubMed Central

Yin, Honglei; Xu, Lin; Shao, Yechang; Li, Liping; Wan, Chengsong

2016-01-01

Objectives The objective of this study was to estimate the features of suicide rate and its association with economic development and stock market during the past decade in the People’s Republic of China. Methods Official data were gathered and analyzed in the People’s Republic of China during the period 2004–2013. Nationwide suicide rate was stratified by four year age-groups, sex, urban/rural areas, and regions (East, Central, and West). Annual economic indexes including gross domestic product (GDP) per capita and rural and urban income per capita were all adjusted for inflation. Variation coefficient of market index (VCMI) was also included as an economic index to measure the fluctuation of the stock market. Negative binomial regression was performed to examine the time trend of region-level suicide rates and effects of sex, age, urban/rural area, region, and economic index on the suicide rates. Results Suicide rates of each age-group, sex, urban/rural area, and region were generally decreased from 2004 to 2013, while annual GDP per capita and rural and urban income per capita were generally increased by year. VCMI fluctuated largely, which peaked around 2009 and decreased after that time. Negative binomial regression showed that the decreased suicide rate in East and Central rural areas was the main cause of the decrease in suicide rate in the People’s Republic of China. Suicide rate in the People’s Republic of China for the study period increased with age and was higher in rural than in urban area, higher in males than in females, and the highest in the Central region. When GDP per capita increased by 2,787 RMB, the suicide rate decreased by 0.498 times. VCMI showed no significant relationship with suicide rate in the negative binomial regression. Conclusion Suicide rate decreased in 2004–2013; varied among different age-groups, sex, urban/rural areas, and regions; and was negatively associated with the economic growth in the People’s Republic of China. Stock market showed no relationship with suicide rate, but this finding needs to be verified in a future study. PMID:27994468

Disclosure of HIV serostatus to male partner and use of modern contraceptives among women receiving HIV care services in Kampala, Uganda.

PubMed

Zalwango, Vivian W; Tweheyo, Raymond; Makumbi, Fredrick

2013-11-01

To investigate whether disclosure of HIV status is associated with use of modern contraceptives (MCs) among women attending HIV care services at an AIDS Information Center (AIC) in an urban setting in Uganda. In a cross-sectional study between March and April 2010, HIV-positive married women aged 15-49years who had received their HIV-positive serostatus results at least 4weeks previously were interviewed at the AIC, Kampala, Uganda. Female use of MCs was compared by HIV disclosure to male marital partners. Log-binomial regression models were used to obtain crude and adjusted prevalence risk ratios (PRRs) and corresponding 95% confidence intervals (CIs). Nearly three-quarters (72.6%) of the women had disclosed their HIV-positive status to their partner. Overall, use of MCs was reported by 41.0% of the participants. Use of only 1 MC method was similar between those disclosing (81.1%) and those not disclosing (84.3%), but use of dual methods tended to be higher among disclosers (14.4%) than among non-disclosers (10.8%). In adjusted analyses, MC use was 41.0% lower among disclosers than among non-disclosers (adjusted PRR, 0.59; 95% CI, 0.46-0.77). HIV serostatus disclosure was associated with lower use of MCs among HIV-positive women in Kampala, Uganda. © 2013.

Social determinants of leprosy in a hyperendemic State in North Brazil

PubMed Central

Monteiro, Lorena Dias; Mota, Rosa Maria Salani; Martins-Melo, Francisco Rogerlândio; Alencar, Carlos Henrique; Heukelbach, Jorg

2017-01-01

ABSTRACT OBJECTIVE To identify the socioeconomic, demographic, operational, and health service-related factors associated with the occurrence of leprosy in a hyperendemic State in North Brazil. METHODS This is an ecological study based on secondary data from the Sistema de Informações de Agravos de Notificação in municipalities of the State of Tocantins from 2001 to 2012. Units of analysis were the 139 municipalities of the State. Negative binomial log linear regression models were used to estimate incidence rate ratios. RESULTS In bivariate analysis, the incidence rate ratios were significantly higher for municipalities with higher income ratio of the poorest 20.0% (1.47; 95%CI 1.19–1.81) and better Municipal Human Development Index (1.53; 95%CI 1.14–2.06). In multivariate analysis, the incidence rate ratios were significantly higher in municipalities with higher proportion of immigrants (1.31; 95%CI 1.11–1.55) and higher proportion of households with waste collection (1.37; 95%CI 1.11–1.69). There was a significant reduction in the incidence rate ratio with increased coverage of the Bolsa Família Program (0.98; 95%CI 0.96–0.99). CONCLUSIONS Control programs need to focus on activities in municipalities of greater social vulnerability with intersectoral investment for the improvement of the living conditions of the population. PMID:28746575

Effects of prediabetes mellitus alone or plus hypertension on subsequent occurrence of cardiovascular disease and diabetes mellitus: longitudinal study.

PubMed

Qiu, Miaoyan; Shen, Weili; Song, Xiaomin; Ju, Liping; Tong, Wenxin; Wang, Haiyan; Zheng, Sheng; Jin, Yan; Wu, Yixin; Wang, Weiqing; Tian, Jingyan

2015-03-01

Whether prediabetes mellitus alone or combined with other disorders means a higher risk for cardiovascular disease (CVD) is still controversial. This study aimed to investigate the association between prediabetes mellitus and CVD and diabetes mellitus and to explore whether prediabetes mellitus alone or combined with other syndromes, such as hypertension, could promote CVD risks significantly. This longitudinal population-based study of 1609 residents from Shanghai in Southern China was conducted between 2002 and 2014. Participants with a history of CVD at baseline were excluded from analysis. Multivariate log-binomial regression models were used to adjust possible coexisting factors. Incidence of CVD during follow-up was 10.1%. After adjusting for age, sex, and other factors, the association between prediabetes mellitus and CVD was not observed. When hypertension was incorporated in stratifying factors, adjusted CVD risk was elevated significantly (odds ratio, 2.41; 95% confidence interval, 1.25-4.64) in prediabetes mellitus and hypertension combined group, and coexistence of diabetes mellitus and hypertension made CVD risk highly significantly increased, reaching 3.43-fold higher than the reference group. Blood glucose level within prediabetic range is significantly associated with elevated risks for diabetes mellitus after multivariable adjustment, but only when it is concurrent with other disorders, such as hypertension, it will significantly increase CVD risk. © 2015 American Heart Association, Inc.

Gender and Socioeconomic Status in Relation to Weight Perception and Weight Control Behavior in Korean Adults

PubMed Central

Joh, Hee-Kyung; Oh, Juhwan; Lee, Hae-Jeung; Kawachi, Ichiro

2013-01-01

Aim In Korea, obesity is more prevalent among men and lower socioeconomic groups. To explain this obesity disparity, we compared weight perception and weight control behavior across gender and socioeconomic status (SES). Methods We analyzed data from 16,260 participants aged 20 years or older in a nationally representative cross-sectional survey. SES indicators included education and income levels. Weight under-perception was defined when participants considered themselves lighter than their measured BMI status. Either no active or inappropriate weight control (i.e., trying to gain weight in obese individuals) was considered to be unhealthy patterns. Multivariate prevalence ratios were calculated using log-binomial regressions. Results Men had a higher prevalence of weight under-perception (24.5 vs. 11.9%) and unhealthy patterns of weight control behavior (57 vs. 40%) than women. Low education level was associated with weight under-perception (ptrend = 0.022 in men, ptrend ℋ 0.001 in women). Both education and income levels were significantly associated with patterns of weight control behavior (for education: ptrend ℋ 0.001 in men and women; for income: ptrend = 0.047 in men, ptrend ℋ 0.001 in women). Conclusion Weight perception and weight control behavior significantly varied by gender and SES. Public actions should be directed toward improving perception and behavior of high-risk populations. PMID:23429009

The association between states' texting regulations and the prevalence of texting while driving among U.S. high school students.

PubMed

Rudisill, Toni M; Zhu, Motao

2015-12-01

To determine which distracted driving laws were associated with decreased texting while driving among U.S. teenage drivers. Data from the 2013 Youth Risk Behavior Surveillance System survey were merged with states' distracted driving legislation. The prevalence of texting while driving was assessed for different laws using log-binomial regression. Approximately 39.0% of students reported texting while driving at least once in the 30 days before survey. Compared to states with universal texting bans along with young driver all cellphone bans, the adjusted ratio of texting while driving was 0.94 (95% confidence interval [CI], 0.77-1.16) in states with no bans, 1.33 (95% CI, 1.11-1.58) for young driver bans only, 1.24 (95% CI, 1.00-1.52) in states with bans for young drivers but no young driver all cellphone bans, and 0.89 (95% CI, 0.66-1.19) in states with universal texting bans. The prevalence of texting was 28% less in states with delays of full licensure for texting offenses (prevalence ratio = 0.72; 95% CI, 0.59-0.88). Universal texting bans along with young driver all cellphone bans may be more effective in reducing texting while driving. Delays of full licensure may dissuade young drivers from texting and driving. Copyright © 2015 Elsevier Inc. All rights reserved.

Social networks and patterns of health risk behaviours over two decades: A multi-cohort study.

PubMed

Kauppi, Maarit; Elovainio, Marko; Stenholm, Sari; Virtanen, Marianna; Aalto, Ville; Koskenvuo, Markku; Kivimäki, Mika; Vahtera, Jussi

2017-08-01

To determine the associations between social network size and subsequent long-term health behaviour patterns, as indicated by alcohol use, smoking, and physical activity. Repeat data from up to six surveys over a 15- or 20-year follow-up were drawn from the Finnish Public Sector study (Raisio-Turku cohort, n=986; Hospital cohort, n=7307), and the Health and Social Support study (n=20,115). Social network size was determined at baseline, and health risk behaviours were assessed using repeated data from baseline and follow-up. We pooled cohort-specific results from repeated-measures log-binomial regression with the generalized estimating equations (GEE) method using fixed-effects meta-analysis. Participants with up to 10 members in their social network at baseline had an unhealthy risk factor profile throughout the follow-up. The pooled relative risks adjusted for age, gender, survey year, chronic conditions and education were 1.15 for heavy alcohol use (95% CI: 1.06-1.24), 1.19 for smoking (95% CI: 1.12-1.27), and 1.25 for low physical activity (95% CI: 1.21-1.29), as compared with those with >20 members in their social network. These associations appeared to be similar in subgroups stratified according to gender, age and education. Social network size predicted persistent behaviour-related health risk patterns up to at least two decades. Copyright © 2017 Elsevier Inc. All rights reserved.

Playgroup Participation and Social Support Outcomes for Mothers of Young Children: A Longitudinal Cohort Study

PubMed Central

Hancock, Kirsten J.; Cunningham, Nadia K.; Lawrence, David; Zarb, David; Zubrick, Stephen R.

2015-01-01

Objective This study aimed to examine friendship networks and social support outcomes for mothers according to patterns of playgroup participation. Methods Data from the Longitudinal Study of Australian Children were used to examine the extent to which patterns of playgroup participation across the ages of 3–19 months (Wave 1) and 2–3 years (Wave 2) were associated with social support outcomes for mothers at Wave 3 (4–5 years) and four years later at Wave 5 (8–9 years). Analyses were adjusted for initial friendship attachments at Wave 1 and other socio-demographic characteristics. Results Log-binomial regression models estimating relative risks showed that mothers who never participated in a playgroup, or who participated at either Wave 1 or Wave 2 only, were 1.7 and 1.8 times as likely to report having no support from friends when the child was 4–5 years, and 2.0 times as likely to have no support at age 8–9 years, compared with mothers who persistently participated in playgroup at both Wave 1 and Wave 2. Conclusion These results provide evidence that persistent playgroup participation may acts as a protective factor against poor social support outcomes. Socially isolated parents may find playgroups a useful resource to build their social support networks. PMID:26181426

Driving kids to smoke? Children's reported exposure to smoke in cars and early smoking initiation.

PubMed

Glover, Marewa; Scragg, Robert; Min, Sandar; Kira, Anette; Nosa, Vili; McCool, Judith; Bullen, Chris

2011-11-01

The health risks associated with second hand smoke (SHS) are well-known. However, little is known about exposure to SHS in cars and risk of smoking uptake. This paper investigates the association between pre-adolescents reported exposure to smoking in cars and prevalence of early stage smoking activity. Data from Keeping Kids Smokefree baseline surveys of students were used to investigate smoking status and reported exposure to smoking in cars. Log binomial regression analyses were used to investigate if reported exposure to SHS in cars was associated with smoking prevalence. 83% of 5676 students invited took part. After controlling for all variables reported exposure to smoking in cars and homes were significantly associated with increased risk of initiated smoking (RR 1.87, 95% CI 1.43-2.44, and RR 1.5, 95% CI 1.13-1.97, respectively). Exposure to smoking in cars was substantially and significantly associated with risk of current smoking (RR 3.21, 95% CI 1.45-7.08). Early smoking uptake is associated with students' reported exposure to smoking in cars which confirms the importance of protecting children from SHS. Smoking in cars is under parental control and therefore modifiable. Moreover, children's reports of SHlS exposure offer a simple way of identifying families who can be targeted for tobacco control interventions. Copyright © 2011 Elsevier Ltd. All rights reserved.

Timeliness and completeness of vaccination and risk factors for low and late vaccine uptake in young children living in rural southern Tanzania.

PubMed

Le Polain de Waroux, Olivier; Schellenberg, Joanna R Armstrong; Manzi, Fatuma; Mrisho, Mwifadhi; Shirima, Kizito; Mshinda, Hassan; Alonso, Pedro; Tanner, Marcel; Schellenberg, David M

2013-06-01

We studied coverage and timeliness of vaccination and risk factors for low and delayed vaccine uptake in children aged <2 years in rural Tanzania. We used data from a cluster survey conducted in 2004, which included 1403 children. Risk factors were analysed by log-binomial regression adjusted for the clustering. The analysis was restricted to BCG, first and third dose of Diphtheria-Tetanus-Pertussis vaccines (DTP-1 and DTP-3) and first dose of measles-containing vaccine (MCV-1). Coverage for BCG, DTP-1, DTP-3 and MCV-1 was 94%, 96%, 90% and 86%, respectively. Delayed vaccination (>1 month after the recommended age) occurred in 398/1205 (33%) children for BCG, 404/1189 (34%) for DTP-1, 683/990 (69%) for DTP-3 and 296/643 (46%) for MCV-1. Coverage was lower for all vaccines except DTP-1 in children living ≥5 km from a healthcare facility. Delayed uptake was associated with poverty. Low and delayed MCV-1 vaccination was associated with low maternal education. Delayed BCG vaccination was associated with ethnicity and rainy season. Despite reasonably high vaccination coverage, we observed substantial vaccination delays, particularly for DTP-3 and MCV-1. We found specific factors associated with low and/or delayed vaccine uptake. These findings can help to improve strategies to reach children who remain inadequately protected.

[Tobacco and alcohol consumption according to workday in Spain].

PubMed

García-Díaz, Vanesa; Fernández-Feito, Ana; Arias, Lucía; Lana, Alberto

2015-01-01

To examine the association between smoking and alcohol consumption and the type of working day in the Spanish population Cross-sectional study among employees residing in Spain aged >18 years (N=8,736). We took data from the National Health Survey (2011-2012). Information was collected on the type of working day (morning, afternoon, evening, part-time, reduced hours, and shift-work) and smoking and drinking habits. Demographic characteristics and health- and work-related factors were also taken into account. Adjusted odds ratios (aOR) and 95% confidence intervals (95%CI) were calculated through log-binomial regressions. Among respondents, 32.1% smoked regularly, especially those working the night shift (43.5%). Moderate alcohol consumption was found in 54.8% of workers and excessive consumption in 1.5%. Most of the moderate and heavy drinkers worked part-time, with 57.6% and 1.8% respectively. The aOR of being a smoker was higher among night workers (OR=1.58; 95% CI: 1.01-2.46). None of the work shifts were significantly associated with alcohol consumption. Night shift work was associated with regular smoking. This collective of workers should be monitored closely by occupational health services and regularly undergo programs to control tobacco consumption and smoking-related diseases. Additional research to elucidate the reasons for this association could help to achieve preventive and therapeutic success. Copyright © 2015 SESPAS. Published by Elsevier Espana. All rights reserved.

Recurrence of preterm birth and perinatal mortality in northern Tanzania: registry-based cohort study.

PubMed

Mahande, Michael J; Daltveit, Anne K; Obure, Joseph; Mmbaga, Blandina T; Masenga, Gileard; Manongi, Rachel; Lie, Rolv T

2013-08-01

To estimate the recurrence risk of preterm delivery and estimate the perinatal mortality in repeated preterm deliveries. Prospective study in Tanzania of 18 176 women who delivered a singleton between 2000 and 2008 at KCMC hospital. The women were followed up to 2010 for consecutive births. A total of 3359 women were identified with a total of 3867 subsequent deliveries in the follow-up period. Recurrence risk of preterm birth and perinatal mortality was estimated using log-binomial regression and adjusted for potential confounders. For women with a previous preterm birth, the risk of preterm birth in a subsequent pregnancy was 17%. This recurrence risk was estimated to be 2.7-fold (95% CI: 2.1-3.4) of the risk of women with a previous term birth. The perinatal mortality of babies in a second preterm birth of the same woman was 15%. Babies born at term who had an older sibling that was born preterm had a perinatal mortality of 10%. Babies born at term who had an older sibling who was also born at term had a perinatal mortality of 1.7%. Previous delivery of a preterm infant is a strong predictor of future preterm births in Tanzania. Previous or repeated preterm births increase the risk of perinatal death substantially in the subsequent pregnancy. © 2013 Blackwell Publishing Ltd.

The association between states’ texting regulations and the prevalence of texting while driving among U.S. high school students

PubMed Central

Rudisill, Toni M.; Zhu, Motao

2015-01-01

Purpose To determine which distracted driving laws were associated with decreased texting while driving among U.S. teenage drivers. Methods Data from the 2013 Youth Risk Behavior Surveillance System survey were merged with state’s distracted driving legislation. The prevalence of texting while driving was assessed for different laws using log-binomial regression. Results Approximately 39.0% of students reported texting while driving at least once in the 30 days before survey. Compared to states with universal texting bans along with young driver all cellphone bans, the adjusted ratio of texting while driving was 0.94 (95% confidence interval [CI], 0.77–1.16) in states with no bans, 1.33 (95% CI, 1.11–1.58) for young driver bans only, 1.24 (95% CI, 1.00–1.52) in states with bans for young drivers but no young driver all cellphone bans, and 0.89 (95% CI, 0.66–1.19) in states with universal texting bans. The prevalence of texting was 28% less in states with delays of full licensure for texting offenses (prevalence ratio = 0.72; 95% CI, 0.59–0.88). Conclusions Universal texting bans along with young driver all cellphone bans may be more effective in reducing texting while driving. Delays of full licensure may dissuade young drivers from texting and driving. PMID:26688117

Acquired Color Vision Defects and Hexane Exposure: A Study of San Francisco Bay Area Automotive Mechanics

PubMed Central

Beckman, Stella; Eisen, Ellen A.; Bates, Michael N.; Liu, Sa; Haegerstrom-Portnoy, Gunilla; Hammond, S. Katharine

2016-01-01

Occupational exposure to solvents, including n-hexane, has been associated with acquired color vision defects. Blue-yellow defects are most common and may be due to neurotoxicity or retinal damage. Acetone may potentiate the neurotoxicity of n-hexane. We present results on nonhexane solvent and hexane exposure and color vision from a cross-sectional study of 835 automotive repair workers in the San Francisco Bay Area, California (2007–2013). Cumulative exposure was estimated from self-reported work history, and color vision was assessed using the Lanthony desaturated D-15 panel test. Log-binomial regression was used to estimate prevalence ratios for color vision defects. Acquired color vision defects were present in 29% of participants, of which 70% were blue-yellow. Elevated prevalence ratios were found for nonhexane solvent exposure, with a maximum of 1.31 (95% confidence interval (CI): 0.86, 2.00) for blue-yellow. Among participants aged ≤50 years, the prevalence ratio for blue-yellow defects was 2.17 (95% CI: 1.03, 4.56) in the highest quartile of nonhexane solvent exposure and 1.62 (95% CI: 0.97, 2.72) in the highest category of exposure to hexane with acetone coexposure. Cumulative exposures to hexane and nonhexane solvents in the highest exposure categories were associated with elevated prevalence ratios for color vision defects in younger participants. PMID:27188942

Mycobacterium tuberculosis infection among persons who inject drugs in San Diego, California.

PubMed

Armenta, R F; Collins, K M; Strathdee, S A; Bulterys, M A; Munoz, F; Cuevas-Mota, J; Chiles, P; Garfein, R S

2017-04-01

Persons who inject drugs (PWID) might be at increased risk for Mycobacterium tuberculosis infection and reactivation of latent tuberculous infection (LTBI) due to their injection drug use. To determine prevalence and correlates of M. tuberculosis infection among PWID in San Diego, California, USA. PWID aged 18 years underwent standardized interviews and serologic testing using an interferon-gamma release assay (IGRA) for LTBI and rapid point-of-care assays for human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infections. Independent correlates of M. tuberculosis infection were identified using multivariable log-binomial regression. A total of 500 participants met the eligibility criteria. The mean age was 43.2 years (standard deviation 11.6); most subjects were White (52%) or Hispanic (30.8%), and male (75%). Overall, 86.7% reported having ever traveled to Mexico. Prevalence of M. tuberculosis infection was 23.6%; 0.8% were co-infected with HIV and 81.7% were co-infected with HCV. Almost all participants (95%) had been previously tested for M. tuberculosis; 7.6% had been previously told they were infected. M. tuberculosis infection was independently associated with being Hispanic, having longer injection histories, testing HCV-positive, and correctly reporting that people with 'sleeping' TB cannot infect others. Strategies are needed to increase awareness about and treatment for M. tuberculosis infection among PWID in the US/Mexico border region.

Employment Precariousness and Poor Mental Health: Evidence from Spain on a New Social Determinant of Health

PubMed Central

Vives, Alejandra; Amable, Marcelo; Ferrer, Montserrat; Moncada, Salvador; Llorens, Clara; Muntaner, Carles; Benavides, Fernando G.; Benach, Joan

2013-01-01

Background. Evidence on the health-damaging effects of precarious employment is limited by the use of one-dimensional approaches focused on employment instability. This study assesses the association between precarious employment and poor mental health using the multidimensional Employment Precariousness Scale. Methods. Cross-sectional study of 5679 temporary and permanent workers from the population-based Psychosocial Factors Survey was carried out in 2004-2005 in Spain. Poor mental health was defined as SF-36 mental health scores below the 25th percentile of the Spanish reference for each respondent's sex and age. Prevalence proportion ratios (PPRs) of poor mental health across quintiles of employment precariousness (reference: 1st quintile) were calculated with log-binomial regressions, separately for women and men. Results. Crude PPRs showed a gradient association with poor mental health and remained generally unchanged after adjustments for age, immigrant status, socioeconomic position, and previous unemployment. Fully adjusted PPRs for the 5th quintile were 2.54 (95% CI: 1.95–3.31) for women and 2.23 (95% CI: 1.86–2.68) for men. Conclusion. The study finds a gradient association between employment precariousness and poor mental health, which was somewhat stronger among women, suggesting an interaction with gender-related power asymmetries. Further research is needed to strengthen the epidemiological evidence base and to inform labour market policy-making. PMID:23431322

Unplanned pregnancy: does past experience influence the use of a contraceptive method?

PubMed

Matteson, Kristen A; Peipert, Jeffrey F; Allsworth, Jenifer; Phipps, Maureen G; Redding, Colleen A

2006-01-01

To investigate whether women between the ages of 14 and 25 years with a past unplanned pregnancy were more likely to use a contraceptive method compared with women without a history of unplanned pregnancy. We analyzed baseline data of 424 nonpregnant women between the ages of 14 and 25 years enrolled in a randomized trial to prevent sexually transmitted diseases and unplanned pregnancy (Project PROTECT). Women at high risk for sexually transmitted diseases or unplanned pregnancy were included. Participants completed a demographic, substance use, and reproductive health questionnaire. We compared women with and without a history of unplanned pregnancy using bivariate analysis and log binomial regression. The prevalence of past unplanned pregnancy in this sample was 43%. Women reporting an unplanned pregnancy were older, and had less education, and were more likely to be nonwhite race or ethnicity. History of an unplanned pregnancy was not associated with usage of a contraceptive method (relative risk 1.01, 95% confidence interval 0.87-1.16) in bivariate analysis or when potential confounders were accounted for in the analysis (adjusted relative risk 1.10, 95% confidence interval 0.95-1.28). Several factors were associated with both unplanned pregnancy and overall contraceptive method use in this population. However, a past unplanned pregnancy was not associated with overall contraceptive method usage. Future studies are necessary to investigate the complex relationship between unplanned pregnancy and contraceptive method use. II-2.

Recall of Anti-Tobacco Advertisements and Effects on Quitting Behavior: Results From the California Smokers Cohort

PubMed Central

Leas, Eric C.; Myers, Mark G.; Strong, David R.; Hofstetter, C. Richard

2015-01-01

Objectives. We assessed whether an anti-tobacco television advertisement called “Stages,” which depicted a woman giving a brief emotional narrative of her experiences with tobacco use, would be recalled more often and have a greater effect on smoking cessation than 3 other advertisements with different intended themes. Methods. Our data were derived from a sample of 2596 California adult smokers. We used multivariable log-binomial and modified Poisson regression models to calculate respondents’ probability of quitting as a result of advertisement recall. Results. More respondents recalled the “Stages” ad (58.5%) than the 3 other ads (23.1%, 23.4%, and 25.6%; P < .001). Respondents who recalled “Stages” at baseline had a higher probability than those who did not recall the ad of making a quit attempt between baseline and follow-up (adjusted risk ratio [RR] = 1.18; 95% confidence interval [CI] = 1.03, 1.34) and a higher probability of being in a period of smoking abstinence for at least a month at follow-up (adjusted RR = 1.55; 95% CI = 1.02, 2.37). Conclusions. Anti-tobacco television advertisements that depict visceral and personal messages may be recalled by a larger percentage of smokers and may have a greater impact on smoking cessation than other types of advertisements. PMID:25521871

Understanding poisson regression.

PubMed

Hayat, Matthew J; Higgins, Melinda

2014-04-01

Nurse investigators often collect study data in the form of counts. Traditional methods of data analysis have historically approached analysis of count data either as if the count data were continuous and normally distributed or with dichotomization of the counts into the categories of occurred or did not occur. These outdated methods for analyzing count data have been replaced with more appropriate statistical methods that make use of the Poisson probability distribution, which is useful for analyzing count data. The purpose of this article is to provide an overview of the Poisson distribution and its use in Poisson regression. Assumption violations for the standard Poisson regression model are addressed with alternative approaches, including addition of an overdispersion parameter or negative binomial regression. An illustrative example is presented with an application from the ENSPIRE study, and regression modeling of comorbidity data is included for illustrative purposes. Copyright 2014, SLACK Incorporated.

An empirical study of statistical properties of variance partition coefficients for multi-level logistic regression models

USGS Publications Warehouse

Li, Ji; Gray, B.R.; Bates, D.M.

2008-01-01

Partitioning the variance of a response by design levels is challenging for binomial and other discrete outcomes. Goldstein (2003) proposed four definitions for variance partitioning coefficients (VPC) under a two-level logistic regression model. In this study, we explicitly derived formulae for multi-level logistic regression model and subsequently studied the distributional properties of the calculated VPCs. Using simulations and a vegetation dataset, we demonstrated associations between different VPC definitions, the importance of methods for estimating VPCs (by comparing VPC obtained using Laplace and penalized quasilikehood methods), and bivariate dependence between VPCs calculated at different levels. Such an empirical study lends an immediate support to wider applications of VPC in scientific data analysis.

Factors Associated with Dental Caries in a Group of American Indian Children at age 36 Months

PubMed Central

Warren, John J.; Blanchette, Derek; Dawson, Deborah V.; Marshall, Teresa A.; Phipps, Kathy R.; Starr, Delores; Drake, David R.

2015-01-01

Objectives Early childhood caries (ECC) is rampant among American Indian children, but there has been relatively little study of this problem. This paper reports on risk factors for caries for a group of American Indian children at age 36 months as part of a longitudinal study. Methods Pregnant women from a Northern Plains Tribal community were recruited to participate in a longitudinal study of caries and caries risk factors. Standardized dental examinations were completed on children and questionnaires were completed by mothers at baseline and when children were 4, 8, 12, 16, 22, 28 and 36 months of age. Examinations were surface-specific for dental caries, and the questionnaires collected data on demographic, dietary and behavioral factors. Non-parametric bivariate tests and logistic regression models were used to identify risk factors for caries at 36 months, and negative binomial regression was used to identify factors related to caries severity (dmf counts). Results Among the 232 children, and caries prevalence for cavitated lesions was 80%, with an additional 15% having only non-cavitated lesions. The mean dmfs was 9.6, and of the total dmfs, nearly 62% of affected surfaces were decayed, 31% were missing, and 7% were filled. Logistic regression identified higher added sugar beverage consumption, younger maternal age at baseline, higher maternal DMFS at baseline, and greater number of people in the household as significant (p<0.05) risk factors. Negative binomial regression found that only maternal DMFS was associated with child dmf counts. Conclusions By the age of 36 months, dental caries is nearly universal in this population of American Indian children. Caries risk factors included sugared beverage consumption, greater household size and maternal factors, but further analyses are needed to better understand caries in this population. PMID:26544674

Efficacy and cost-effectiveness of a physiotherapy program for chronic rotator cuff pathology: A protocol for a randomised, double-blind, placebo-controlled trial

PubMed Central

Bennell, Kim; Coburn, Sally; Wee, Elin; Green, Sally; Harris, Anthony; Forbes, Andrew; Buchbinder, Rachelle

2007-01-01

Background Chronic rotator cuff pathology (CRCP) is a common shoulder condition causing pain and disability. Physiotherapy is often the first line of management for CRCP yet there is little conclusive evidence to support or refute its effectiveness and no formal evaluation of its cost-effectiveness. Methods/Design This randomised, double-blind, placebo-controlled trial will involve 200 participants with CRCP recruited from medical practices, outpatient departments and the community via print and radio media. Participants will be randomly allocated to a physiotherapy or placebo group using concealed allocation stratified by treating physiotherapist. Both groups will receive 10 sessions of individual standardised treatment over 10 weeks from one of 10 project physiotherapists. For the following 12 weeks, the physiotherapy group will continue a home exercise program and the placebo group will receive no treatment. The physiotherapy program will comprise shoulder joint and spinal mobilisation, soft tissue massage, postural taping, and home exercises for scapular control, posture and rotator cuff strengthening. The placebo group will receive inactive ultrasound and gentle application of an inert gel over the shoulder region. Blinded assessment will be conducted at baseline and at 10 weeks and 22 weeks after randomisation. The primary outcome measures are self reported questionnaires including the shoulder pain and disability index (SPADI), average pain on an 11-point numeric rating scale and participant perceived global rating of change. Secondary measures include Medical Outcomes Study 36-item short form (SF-36), Assessment of Quality of Life index, numeric rating scales for shoulder pain and stiffness, participant perceived rating of change for pain, strength and stiffness, and manual muscle testing for shoulder strength using a handheld dynamometer. To evaluate cost-effectiveness, participants will record the use of all health-related treatments in a log-book returned to the assessor monthly. To test the effect of the intervention using an intention-to-treat analysis, linear regression modelling will be applied adjusting for baseline outcome values and other demographic characteristics. Participant measures of perceived change will be compared between groups by calculating the relative risks and their 95% confidence intervals at each time point using log binomial regression. Discussion Results from this trial will contribute to the evidence regarding the effectiveness of a physiotherapy program for the management of CRCP. Trial registration NIH Clinical Trials Registry # NCT00415441 PMID:17761004

Log and tree sawing times for hardwood mills

Treesearch

Everette D. Rast

1974-01-01

Data on 6,850 logs and 1,181 trees were analyzed to predict sawing times. For both logs and trees, regression equations were derived that express (in minutes) sawing time per log or tree and per Mbf. For trees, merchantable height is expressed in number of logs as well as in feet. One of the major uses for the tables of average sawing times is as a bench mark against...

School shootings during 2013-2015 in the USA.

PubMed

Kalesan, Bindu; Lagast, Kinan; Villarreal, Marcos; Pino, Elizabeth; Fagan, Jeffrey; Galea, Sandro

2017-10-01

Data on the factors associated with school shootings in the USA are limited. The public conversation has often suggested several factors that may be linked to these events, however with little empirical support. Aiming to fill this gap, we describe the characteristics of school shooting incidents in the USA between 2013 and 2015 and explore whether four factors that represent domains of firearm policy, educational policy and epidemiological risk factors for intentional firearm injuries-background check (BC) policies, per capita mental health expenditures (MHE), K-12 education expenditure (KEE) and urbanicity-were associated with school shootings during this period. We searched LexisNexis, a newspaper and broadcast media databases for school shooting incidents from 1 January 2013 to 31 December 2015. Presence of BC laws was extracted from legal information in LexisNexis. State-level covariates of per capita MHE (2013), KEE (2013) and urbanicity (2010) rates were obtained from publicly available data sources. We used negative binomial regression models accounting for clustering by state to explore unadjusted associations between the BC laws, state-level covariates and school shootings to report IRR and 95% CI. We documented 154 school shootings (35, 55 and 64 each year). In unadjusted models, BC for firearm purchase (IRR=0.55, 95% CI 0.39 to 0.76), ammunition purchase (IRR=0.11, 95% CI 0.05 to 0.27), log per capita MHE (IRR=0.58, 95% CI 0.37 to 0.90), log per-capita KEE (IRR=0.09, 9% CI 0.02 to 0.29) and urbanicity (IRR=0.97, 95% CI 0.96 to 0.99) were associated with school shooting. School shootings are less likely in states with BC laws, higher MHE and KEE, and with greater per cent urban population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Modelling infant mortality rate in Central Java, Indonesia use generalized poisson regression method

NASA Astrophysics Data System (ADS)

Prahutama, Alan; Sudarno

2018-05-01

The infant mortality rate is the number of deaths under one year of age occurring among the live births in a given geographical area during a given year, per 1,000 live births occurring among the population of the given geographical area during the same year. This problem needs to be addressed because it is an important element of a country’s economic development. High infant mortality rate will disrupt the stability of a country as it relates to the sustainability of the population in the country. One of regression model that can be used to analyze the relationship between dependent variable Y in the form of discrete data and independent variable X is Poisson regression model. Recently The regression modeling used for data with dependent variable is discrete, among others, poisson regression, negative binomial regression and generalized poisson regression. In this research, generalized poisson regression modeling gives better AIC value than poisson regression. The most significant variable is the Number of health facilities (X1), while the variable that gives the most influence to infant mortality rate is the average breastfeeding (X9).

Maternal Early Life Factors Associated with Hormone Levels and the Risk of Having a Child with an Autism Spectrum Disorder in the Nurses Health Study II

ERIC Educational Resources Information Center

Lyall, Kristen; Pauls, David L.; Santangelo, Susan; Spiegelman, Donna; Ascherio, Alberto

2011-01-01

It is not known whether reproductive factors early in the mother's life influence risk of autism spectrum disorders (ASD). We assessed maternal age at menarche, menstrual cycle characteristics during adolescence, oral contraceptive use prior to first birth, body shape, and body mass index (BMI) in association with ASD using binomial regression in…

Oral health of schoolchildren in Western Australia.

PubMed

Arrow, P

2016-09-01

The West Australian School Dental Service (SDS) provides free, statewide, primary dental care to schoolchildren aged 5-17 years. This study reports on an evaluation of the oral health of children examined during the 2014 calendar year. Children were sampled, based on their date of birth, and SDS clinicians collected the clinical information. Weighted mean values of caries experience were presented. Negative binomial regression modelling was undertaken to test for factors of significance in the rate of caries occurrence. Data from children aged 5-15 years were used (girls = 4616, boys = 4900). Mean dmft (5-10-year-olds), 1.42 SE 0.03; mean DMFT (6-15-year-olds), 0.51 SE 0.01. Negative binomial regression model of permanent tooth caries found higher rates of caries in children who were from non-fluoridated areas (RR 2.1); Aboriginal (RR 2.4); had gingival inflammation (RR 1.5); lower ICSEA level (RR 1.4); and recalled at more than 24-month interval (RR 1.8). The study highlighted poor dental health associated with living in non-fluoridated areas, Aboriginal identity, poor oral hygiene, lower socioeconomic level and having extended intervals between dental checkups. Timely assessments and preventive measures targeted at groups, including extending community water fluoridation, may assist in further improving the oral health of children in Western Australia. © 2015 Australian Dental Association.

Community covariates of malnutrition based mortality among older adults.

PubMed

Lee, Matthew R; Berthelot, Emily R

2010-05-01

The purpose of this study was to identify community level covariates of malnutrition-based mortality among older adults. A community level framework was delineated which explains rates of malnutrition-related mortality among older adults as a function of community levels of socioeconomic disadvantage, disability, and social isolation among members of this group. County level data on malnutrition mortality of people 65 years of age and older for the period 2000-2003 were drawn from the CDC WONDER system databases. County level measures of older adult socioeconomic disadvantage, disability, and social isolation were derived from the 2000 US Census of Population and Housing. Negative binomial regression models adjusting for the size of the population at risk, racial composition, urbanism, and region were estimated to assess the relationships among these indicators. Results from negative binomial regression analysis yielded the following: a standard deviation increase in socioeconomic/physical disadvantage was associated with a 12% increase in the rate of malnutrition mortality among older adults (p < 0.001), whereas a standard deviation increase in social isolation was associated with a 5% increase in malnutrition mortality among older adults (p < 0.05). Community patterns of malnutrition based mortality among older adults are partly a function of levels of socioeconomic and physical disadvantage and social isolation among older adults. 2010 Elsevier Inc. All rights reserved.

Association between adherence to physical activity guidelines and health-related quality of life among individuals with physician-diagnosed arthritis.

PubMed

Austin, Shamly; Qu, Haiyan; Shewchuk, Richard M

2012-10-01

To examine the association between adherence to physical activity guidelines and health-related quality of life (HRQOL) among individuals with arthritis. A cross-sectional sample with 33,071 US adults, 45 years or older with physician-diagnosed arthritis was obtained from 2007 Behavioral Risk Factor Surveillance System survey. We conducted negative binomial regression analysis to examine HRQOL as a function of adherence to physical activity guidelines controlling for physicians' recommendations for physical activity, age, sex, race, education, marital status, employment, annual income, health insurance, personal physician, emotional support, body mass index, activity limitations, health status, and co-morbidities based on Behavioral Model of Health Services Utilization. Descriptive statistics showed that 60% adults with arthritis did not adhere to physical activity guidelines, mean physically and mentally unhealthy days were 7.7 and 4.4 days, respectively. Results from negative binomial regression indicated that individuals who did not adhere to physical activity guidelines had 1.14 days more physically unhealthy days and 1.12 days more mentally unhealthy days than those who adhered controlling for covariates. Adherence to physical activity is important to improve HRQOL for individuals with arthritis. However, adherence is low among this population. Interventions are required to engage individuals with arthritis in physical activity.

Factors Associated with Hospital Length of Stay among Cancer Patients with Febrile Neutropenia

PubMed Central

Rosa, Regis G.; Goldani, Luciano Z.

2014-01-01

Purpose This study sought to evaluate factors associated with hospital length of stay in cancer patients with febrile neutropenia. Methods A prospective cohort study was performed at a single tertiary referral hospital in southern Brazil from October 2009 to August 2011. All adult cancer patients with febrile neutropenia admitted to the hematology ward were evaluated. Stepwise random-effects negative binomial regression was performed to identify risk factors for prolonged length of hospital stay. Results In total, 307 cases of febrile neutropenia were evaluated. The overall median length of hospital stay was 16 days (interquartile range 18 days). According to multiple negative binomial regression analysis, hematologic neoplasms (P = 0.003), high-dose chemotherapy regimens (P<0.001), duration of neutropenia (P<0.001), and bloodstream infection involving Gram-negative multi-drug-resistant bacteria (P = 0.003) were positively associated with prolonged hospital length of stay in patients with febrile neutropenia. The condition index showed no evidence of multi-collinearity effect among the independent variables. Conclusions Hematologic neoplasms, high-dose chemotherapy regimens, prolonged periods of neutropenia, and bloodstream infection with Gram-negative multi-drug-resistant bacteria are predictors of prolonged length hospital of stay among adult cancer patients with febrile neutropenia. PMID:25285790

Mixed effect Poisson log-linear models for clinical and epidemiological sleep hypnogram data

PubMed Central

Swihart, Bruce J.; Caffo, Brian S.; Crainiceanu, Ciprian; Punjabi, Naresh M.

2013-01-01

Bayesian Poisson log-linear multilevel models scalable to epidemiological studies are proposed to investigate population variability in sleep state transition rates. Hierarchical random effects are used to account for pairings of subjects and repeated measures within those subjects, as comparing diseased to non-diseased subjects while minimizing bias is of importance. Essentially, non-parametric piecewise constant hazards are estimated and smoothed, allowing for time-varying covariates and segment of the night comparisons. The Bayesian Poisson regression is justified through a re-derivation of a classical algebraic likelihood equivalence of Poisson regression with a log(time) offset and survival regression assuming exponentially distributed survival times. Such re-derivation allows synthesis of two methods currently used to analyze sleep transition phenomena: stratified multi-state proportional hazards models and log-linear models with GEE for transition counts. An example data set from the Sleep Heart Health Study is analyzed. Supplementary material includes the analyzed data set as well as the code for a reproducible analysis. PMID:22241689

Multivariate regression model for predicting lumber grade volumes of northern red oak sawlogs

Treesearch

Daniel A. Yaussy; Robert L. Brisbin

1983-01-01

A multivariate regression model was developed to predict green board-foot yields for the seven common factory lumber grades processed from northern red oak (Quercus rubra L.) factory grade logs. The model uses the standard log measurements of grade, scaling diameter, length, and percent defect. It was validated with an independent data set. The model...

Using nonlinear quantile regression to estimate the self-thinning boundary curve

Treesearch

Quang V. Cao; Thomas J. Dean

2015-01-01

The relationship between tree size (quadratic mean diameter) and tree density (number of trees per unit area) has been a topic of research and discussion for many decades. Starting with Reineke in 1933, the maximum size-density relationship, on a log-log scale, has been assumed to be linear. Several techniques, including linear quantile regression, have been employed...

Escherichia coli bacteria density in relation to turbidity, streamflow characteristics, and season in the Chattahoochee River near Atlanta, Georgia, October 2000 through September 2008—Description, statistical analysis, and predictive modeling

USGS Publications Warehouse

Lawrence, Stephen J.

2012-01-01

Regression analyses show that E. coli density in samples was strongly related to turbidity, streamflow characteristics, and season at both sites. The regression equation chosen for the Norcross data showed that 78 percent of the variability in E. coli density (in log base 10 units) was explained by the variability in turbidity values (in log base 10 units), streamflow event (dry-weather flow or stormflow), season (cool or warm), and an interaction term that is the cross product of streamflow event and turbidity. The regression equation chosen for the Atlanta data showed that 76 percent of the variability in E. coli density (in log base 10 units) was explained by the variability in turbidity values (in log base 10 units), water temperature, streamflow event, and an interaction term that is the cross product of streamflow event and turbidity. Residual analysis and model confirmation using new data indicated the regression equations selected at both sites predicted E. coli density within the 90 percent prediction intervals of the equations and could be used to predict E. coli density in real time at both sites.

Green lumber grade yields from factory grade logs of three oak species

Treesearch

Daniel A. Yaussy

1986-01-01

Multivariate regression models were developed to predict green board foot yields for the seven common factory lumber grades processed from white, black, and chestnut oak factory grade logs. These models use the standard log measurements of grade, scaling diameter, log length, and proportion of scaling defect. Any combination of lumber grades (such as 1 Common and...

Statistical inference involving binomial and negative binomial parameters.

PubMed

García-Pérez, Miguel A; Núñez-Antón, Vicente

2009-05-01

Statistical inference about two binomial parameters implies that they are both estimated by binomial sampling. There are occasions in which one aims at testing the equality of two binomial parameters before and after the occurrence of the first success along a sequence of Bernoulli trials. In these cases, the binomial parameter before the first success is estimated by negative binomial sampling whereas that after the first success is estimated by binomial sampling, and both estimates are related. This paper derives statistical tools to test two hypotheses, namely, that both binomial parameters equal some specified value and that both parameters are equal though unknown. Simulation studies are used to show that in small samples both tests are accurate in keeping the nominal Type-I error rates, and also to determine sample size requirements to detect large, medium, and small effects with adequate power. Additional simulations also show that the tests are sufficiently robust to certain violations of their assumptions.

Predicting clicks of PubMed articles.

PubMed

Mao, Yuqing; Lu, Zhiyong

2013-01-01

Predicting the popularity or access usage of an article has the potential to improve the quality of PubMed searches. We can model the click trend of each article as its access changes over time by mining the PubMed query logs, which contain the previous access history for all articles. In this article, we examine the access patterns produced by PubMed users in two years (July 2009 to July 2011). We explore the time series of accesses for each article in the query logs, model the trends with regression approaches, and subsequently use the models for prediction. We show that the click trends of PubMed articles are best fitted with a log-normal regression model. This model allows the number of accesses an article receives and the time since it first becomes available in PubMed to be related via quadratic and logistic functions, with the model parameters to be estimated via maximum likelihood. Our experiments predicting the number of accesses for an article based on its past usage demonstrate that the mean absolute error and mean absolute percentage error of our model are 4.0% and 8.1% lower than the power-law regression model, respectively. The log-normal distribution is also shown to perform significantly better than a previous prediction method based on a human memory theory in cognitive science. This work warrants further investigation on the utility of such a log-normal regression approach towards improving information access in PubMed.

Predicting clicks of PubMed articles

PubMed Central

Mao, Yuqing; Lu, Zhiyong

2013-01-01

Predicting the popularity or access usage of an article has the potential to improve the quality of PubMed searches. We can model the click trend of each article as its access changes over time by mining the PubMed query logs, which contain the previous access history for all articles. In this article, we examine the access patterns produced by PubMed users in two years (July 2009 to July 2011). We explore the time series of accesses for each article in the query logs, model the trends with regression approaches, and subsequently use the models for prediction. We show that the click trends of PubMed articles are best fitted with a log-normal regression model. This model allows the number of accesses an article receives and the time since it first becomes available in PubMed to be related via quadratic and logistic functions, with the model parameters to be estimated via maximum likelihood. Our experiments predicting the number of accesses for an article based on its past usage demonstrate that the mean absolute error and mean absolute percentage error of our model are 4.0% and 8.1% lower than the power-law regression model, respectively. The log-normal distribution is also shown to perform significantly better than a previous prediction method based on a human memory theory in cognitive science. This work warrants further investigation on the utility of such a log-normal regression approach towards improving information access in PubMed. PMID:24551386

Impact of cigarette smoking on utilization of nursing home services.

PubMed

Warner, Kenneth E; McCammon, Ryan J; Fries, Brant E; Langa, Kenneth M

2013-11-01

Few studies have examined the effects of smoking on nursing home utilization, generally using poor data on smoking status. No previous study has distinguished utilization for recent from long-term quitters. Using the Health and Retirement Study, we assessed nursing home utilization by never-smokers, long-term quitters (quit >3 years), recent quitters (quit ≤3 years), and current smokers. We used logistic regression to evaluate the likelihood of a nursing home admission. For those with an admission, we used negative binomial regression on the number of nursing home nights. Finally, we employed zero-inflated negative binomial regression to estimate nights for the full sample. Controlling for other variables, compared with never-smokers, long-term quitters have an odds ratio (OR) for nursing home admission of 1.18 (95% CI: 1.07-1.2), current smokers 1.39 (1.23-1.57), and recent quitters 1.55 (1.29-1.87). The probability of admission rises rapidly with age and is lower for African Americans and Hispanics, more affluent respondents, respondents with a spouse present in the home, and respondents with a living child. Given admission, smoking status is not associated with length of stay (LOS). LOS is longer for older respondents and women and shorter for more affluent respondents and those with spouses present. Compared with otherwise identical never-smokers, former and current smokers have a significantly increased risk of nursing home admission. That recent quitters are at greatest risk of admission is consistent with evidence that many stop smoking because they are sick, often due to smoking.

Robust inference in the negative binomial regression model with an application to falls data.

PubMed

Aeberhard, William H; Cantoni, Eva; Heritier, Stephane

2014-12-01

A popular way to model overdispersed count data, such as the number of falls reported during intervention studies, is by means of the negative binomial (NB) distribution. Classical estimating methods are well-known to be sensitive to model misspecifications, taking the form of patients falling much more than expected in such intervention studies where the NB regression model is used. We extend in this article two approaches for building robust M-estimators of the regression parameters in the class of generalized linear models to the NB distribution. The first approach achieves robustness in the response by applying a bounded function on the Pearson residuals arising in the maximum likelihood estimating equations, while the second approach achieves robustness by bounding the unscaled deviance components. For both approaches, we explore different choices for the bounding functions. Through a unified notation, we show how close these approaches may actually be as long as the bounding functions are chosen and tuned appropriately, and provide the asymptotic distributions of the resulting estimators. Moreover, we introduce a robust weighted maximum likelihood estimator for the overdispersion parameter, specific to the NB distribution. Simulations under various settings show that redescending bounding functions yield estimates with smaller biases under contamination while keeping high efficiency at the assumed model, and this for both approaches. We present an application to a recent randomized controlled trial measuring the effectiveness of an exercise program at reducing the number of falls among people suffering from Parkinsons disease to illustrate the diagnostic use of such robust procedures and their need for reliable inference. © 2014, The International Biometric Society.

Sickness absence and psychosocial job quality: an analysis from a longitudinal survey of working Australians, 2005-2012.

PubMed

Milner, Allison; Butterworth, Peter; Bentley, Rebecca; Kavanagh, Anne M; LaMontagne, Anthony D

2015-05-15

Sickness absence is associated with adverse health, organizational, and societal outcomes. Using data from a longitudinal cohort study of working Australians (the Household, Income and Labour Dynamics in Australia (HILDA) Survey), we examined the relationship between changes in individuals' overall psychosocial job quality and variation in sickness absence. The outcome variables were paid sickness absence (yes/no) and number of days of paid sickness absence in the past year (2005-2012). The main exposure variable was psychosocial job quality, measured using a psychosocial job quality index (levels of job control, demands and complexity, insecurity, and perceptions of unfair pay). Analysis was conducted using longitudinal fixed-effects logistic regression models and negative binomial regression models. There was a dose-response relationship between the number of psychosocial job stressors reported by an individual and the odds of paid sickness absence (1 adversity: odds ratio (OR) = 1.26, 95% confidence interval (CI): 1.09, 1.45 (P = 0.002); 2 adversities: OR = 1.28, 95% CI: 1.09, 1.51 (P = 0.002); ≥3 adversities: OR = 1.58, 95% CI: 1.29, 1.94 (P < 0.001)). The negative binomial regression models also indicated that respondents reported a greater number of days of sickness absence in response to worsening psychosocial job quality. These results suggest that workplace interventions aiming to improve the quality of work could help reduce sickness absence. © The Author 2015. 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.

Early Warning Signals of Financial Crises with Multi-Scale Quantile Regressions of Log-Periodic Power Law Singularities.

PubMed

Zhang, Qun; Zhang, Qunzhi; Sornette, Didier

2016-01-01

We augment the existing literature using the Log-Periodic Power Law Singular (LPPLS) structures in the log-price dynamics to diagnose financial bubbles by providing three main innovations. First, we introduce the quantile regression to the LPPLS detection problem. This allows us to disentangle (at least partially) the genuine LPPLS signal and the a priori unknown complicated residuals. Second, we propose to combine the many quantile regressions with a multi-scale analysis, which aggregates and consolidates the obtained ensembles of scenarios. Third, we define and implement the so-called DS LPPLS Confidence™ and Trust™ indicators that enrich considerably the diagnostic of bubbles. Using a detailed study of the "S&P 500 1987" bubble and presenting analyses of 16 historical bubbles, we show that the quantile regression of LPPLS signals contributes useful early warning signals. The comparison between the constructed signals and the price development in these 16 historical bubbles demonstrates their significant predictive ability around the real critical time when the burst/rally occurs.

Binomial outcomes in dataset with some clusters of size two: can the dependence of twins be accounted for? A simulation study comparing the reliability of statistical methods based on a dataset of preterm infants.

PubMed

Sauzet, Odile; Peacock, Janet L

2017-07-20

The analysis of perinatal outcomes often involves datasets with some multiple births. These are datasets mostly formed of independent observations and a limited number of clusters of size two (twins) and maybe of size three or more. This non-independence needs to be accounted for in the statistical analysis. Using simulated data based on a dataset of preterm infants we have previously investigated the performance of several approaches to the analysis of continuous outcomes in the presence of some clusters of size two. Mixed models have been developed for binomial outcomes but very little is known about their reliability when only a limited number of small clusters are present. Using simulated data based on a dataset of preterm infants we investigated the performance of several approaches to the analysis of binomial outcomes in the presence of some clusters of size two. Logistic models, several methods of estimation for the logistic random intercept models and generalised estimating equations were compared. The presence of even a small percentage of twins means that a logistic regression model will underestimate all parameters but a logistic random intercept model fails to estimate the correlation between siblings if the percentage of twins is too small and will provide similar estimates to logistic regression. The method which seems to provide the best balance between estimation of the standard error and the parameter for any percentage of twins is the generalised estimating equations. This study has shown that the number of covariates or the level two variance do not necessarily affect the performance of the various methods used to analyse datasets containing twins but when the percentage of small clusters is too small, mixed models cannot capture the dependence between siblings.

Zero-truncated negative binomial - Erlang distribution

NASA Astrophysics Data System (ADS)

Bodhisuwan, Winai; Pudprommarat, Chookait; Bodhisuwan, Rujira; Saothayanun, Luckhana

2017-11-01

The zero-truncated negative binomial-Erlang distribution is introduced. It is developed from negative binomial-Erlang distribution. In this work, the probability mass function is derived and some properties are included. The parameters of the zero-truncated negative binomial-Erlang distribution are estimated by using the maximum likelihood estimation. Finally, the proposed distribution is applied to real data, the number of methamphetamine in the Bangkok, Thailand. Based on the results, it shows that the zero-truncated negative binomial-Erlang distribution provided a better fit than the zero-truncated Poisson, zero-truncated negative binomial, zero-truncated generalized negative-binomial and zero-truncated Poisson-Lindley distributions for this data.

Binary Logistic Regression Analysis for Detecting Differential Item Functioning: Effectiveness of R[superscript 2] and Delta Log Odds Ratio Effect Size Measures

ERIC Educational Resources Information Center

Hidalgo, Mª Dolores; Gómez-Benito, Juana; Zumbo, Bruno D.

2014-01-01

The authors analyze the effectiveness of the R[superscript 2] and delta log odds ratio effect size measures when using logistic regression analysis to detect differential item functioning (DIF) in dichotomous items. A simulation study was carried out, and the Type I error rate and power estimates under conditions in which only statistical testing…

Analysis of Binary Adherence Data in the Setting of Polypharmacy: A Comparison of Different Approaches

PubMed Central

Esserman, Denise A.; Moore, Charity G.; Roth, Mary T.

2009-01-01

Older community dwelling adults often take multiple medications for numerous chronic diseases. Non-adherence to these medications can have a large public health impact. Therefore, the measurement and modeling of medication adherence in the setting of polypharmacy is an important area of research. We apply a variety of different modeling techniques (standard linear regression; weighted linear regression; adjusted linear regression; naïve logistic regression; beta-binomial (BB) regression; generalized estimating equations (GEE)) to binary medication adherence data from a study in a North Carolina based population of older adults, where each medication an individual was taking was classified as adherent or non-adherent. In addition, through simulation we compare these different methods based on Type I error rates, bias, power, empirical 95% coverage, and goodness of fit. We find that estimation and inference using GEE is robust to a wide variety of scenarios and we recommend using this in the setting of polypharmacy when adherence is dichotomously measured for multiple medications per person. PMID:20414358

QSPR study of polychlorinated diphenyl ethers by molecular electronegativity distance vector (MEDV-4).

PubMed

Sun, Lili; Zhou, Liping; Yu, Yu; Lan, Yukun; Li, Zhiliang

2007-01-01

Polychlorinated diphenyl ethers (PCDEs) have received more and more concerns as a group of ubiquitous potential persistent organic pollutants (POPs). By using molecular electronegativity distance vector (MEDV-4), multiple linear regression (MLR) models are developed for sub-cooled liquid vapor pressures (P(L)), n-octanol/water partition coefficients (K(OW)) and sub-cooled liquid water solubilities (S(W,L)) of 209 PCDEs and diphenyl ether. The correlation coefficients (R) and the leave-one-out cross-validation (LOO) correlation coefficients (R(CV)) of all the 6-descriptor models for logP(L), logK(OW) and logS(W,L) are more than 0.98. By using stepwise multiple regression (SMR), the descriptors are selected and the resulting models are 5-descriptor model for logP(L), 4-descriptor model for logK(OW), and 6-descriptor model for logS(W,L), respectively. All these models exhibit excellent estimate capabilities for internal sample set and good predictive capabilities for external samples set. The consistency between observed and estimated/predicted values for logP(L) is the best (R=0.996, R(CV)=0.996), followed by logK(OW) (R=0.992, R(CV)=0.992) and logS(W,L) (R=0.983, R(CV)=0.980). By using MEDV-4 descriptors, the QSPR models can be used for prediction and the model predictions can hence extend the current database of experimental values.

Increased Prevalence of Chronic Lymphocytic Thyroiditis in Korean Patients with Papillary Thyroid Cancer

PubMed Central

Oh, Chang-Mo; Park, Sohee; Lee, Joo Young; Won, Young-Joo; Shin, Aesun; Kong, Hyun-Joo; Choi, Kui-Sun; Lee, You Jin; Chung, Ki- Wook; Jung, Kyu-Won

2014-01-01

Background In recent years, some reports have suggested that papillary thyroid cancers are more frequently associated with lymphocytic thyroiditis or Hashimoto's thyroiditis. This study investigated a potential increase in the prevalence of chronic lymphocytic thyroiditis among papillary thyroid cancer patients. Materials and Methods We used national epidemiological survey data on thyroid cancer patients diagnosed in 1999, 2005, and 2008. A retrospective medical record survey was conducted by representative sampling of a national cancer incidence database. The analysis included 5,378 papillary thyroid cancer patients aged 20–79 years. We calculated the age-standardized prevalence and age-adjusted prevalence ratios using a binomial regression model with a log link for the prevalence of chronic lymphocytic thyroiditis among papillary thyroid cancer patients by sex for each year. Results The prevalence of chronic lymphocytic thyroiditis among papillary thyroid cancer patients was 4.0% and 12.8% for men and women in 1999, 6.5% and 24.6% in 2005, and 10.7% and 27.6% in 2008, respectively. Between 1999 and 2008, the age-standardized prevalence of chronic lymphocytic thyroiditis increased 4.1-fold in male patients and 2.0-fold in female patients with papillary thyroid cancer. The prevalence of other thyroid diseases, however, did not increase in either gender. Conclusions Among Korean papillary thyroid cancer patients, the prevalence of chronic lymphocytic thyroiditis increased between 1999 and 2008, whereas the prevalence of other thyroid disorders did not change. PMID:24927027

Malnutrition-related early childhood exposures and enamel defects in the permanent dentition: A longitudinal study from the Bolivian Amazon.

PubMed

Masterson, Erin E; Fitzpatrick, Annette L; Enquobahrie, Daniel A; Mancl, Lloyd A; Conde, Esther; Hujoel, Philippe P

2017-10-01

We investigated the relationship between early childhood malnutrition-related measures and subsequent enamel defects in the permanent dentition. This cohort study included 349 Amerindian adolescents (10-17 years, 52% male) from the Bolivian Amazon. Exposures included: stunted growth (height-for-age z-scores), underweight (weight-for-age z-scores), anemia (hemoglobin), acute inflammation (C-reactive protein) and parasitic infection (hookworm). We measured the occurrence (no/yes) and extent (<1/3, 1/3-2/3, >2/3) of enamel defects. We estimated associations between childhood exposures and enamel defect measures using log-binomial and multinomial logistic regression. The prevalence of an enamel defect characterized by an orange peel texture on a large central depression on the labial surface of the central maxillary incisors was 92.3%. During childhood (1-4 years), participants had a high prevalence of stunted growth (75.2%), anemia (56.9%), acute inflammation (39.1%), and hookworm infection (49.6%). We observed associations between childhood height-for-age (OR = 0.65; P = 0.028 for >2/3 extent vs. no EH) and gastrointestinal hookworm infection (OR = 3.43; P = 0.035 for >2/3 extent vs. no defects or <1/3 extent) with enamel defects. The study describes a possibly novel form of enamel hypoplasia and provides evidence for associations of malnutrition-related measures in early childhood, including stunted growth and parasitic helminth infection, with the observed enamel defects. © 2017 Wiley Periodicals, Inc.

Missed Work Due to Occupational Illness among Hispanic Horse Workers.

PubMed

Bush, Ashley M; Westneat, Susan; Browning, Steven R; Swanberg, Jennifer

2018-05-07

Occupational illnesses are inadequately reported for agriculture, an industry dominated by a vulnerable Hispanic population and high fatal and nonfatal injury rates. Work-related illnesses can contribute to missed work, caused by a combination of personal and work factors, with costs to the individual, employer, and society. To better understand agricultural occupational illnesses, 225 Hispanic horse workers were interviewed via community-based convenience sampling. Descriptive statistics, bivariate analyses, and log binomial regression modeling were used to: (1) describe the prevalence of missed work due to work-related illnesses among Hispanic horse workers, (2) examine work-related and personal factors associated with missed work, and (3) identify health symptoms and work-related characteristics potentially associated with missed work. Key findings reveal that having at least one child (PR = 1.71, 95% CI = 1.03, 2.84), having poor self-reported general health (PR = 0.72, 95% CI = 0.48, 1.08), experiencing stress during a typical workday (PR = 2.58, 95% CI = 1.25, 5.32), or spending less time with horses (PR = 1.87, 95% CI = 1.15, 3.05) are significant predictors of missing work. Interventions can be designed to identify workers most susceptible to missing work and provide resources to reduce absenteeism. Future research should examine work-related illness in agricultural horse production, including personal and work-related factors, in order to diminish occupational health disparities among these workers, who are more likely to be employed in hazardous agricultural work. Copyright© by the American Society of Agricultural Engineers.

The association between sugar-sweetened beverages and dental caries among third-grade students in Georgia.

PubMed

Wilder, Jocelyn R; Kaste, Linda M; Handler, Arden; Chapple-McGruder, Theresa; Rankin, Kristin M

2016-01-01

The purpose of this study is to examine the association between sugar-sweetened beverage (SSB) consumption and caries experience among Georgia third graders. The 2010-2011 Georgia Third Grade Oral Health Study provided a school-based sample for analysis. Data were weighted to be representative of the state of Georgia's third graders. Log-binomial regression was used to assess the association between SSB consumption and caries experience after adjusting for socio-demographic and maternal and child oral health characteristics. Georgia third graders consumed approximately two servings of SSB per day on average (1.7, 95% CI 1.6-1.8). Fifty-two percent of Georgia third graders had caries experience. Daily consumption of SSB and prevalence of caries experience differed significantly by demographic characteristics. After adjustment for socio-demographic and maternal oral health characteristics, caries experience increased 22 percent (adjusted PR = 1.2, 95% CI 1.1, 1.3) for every additional reported serving of SSB consumed per day. Higher consumption of SSBs is associated with higher caries prevalence among Georgia third graders after adjustment for important covariates. Consequently, health messages about SSBs from dentists, physicians, and other healthcare providers as well as policy approaches at the school, state, and national levels to limit consumption of SSBs may collectively impact both the development of dental caries and obesity, leading to overall better health for children. © 2015 American Association of Public Health Dentistry.

Adiposity among children in Norway by urbanity and maternal education: a nationally representative study.

PubMed

Biehl, Anna; Hovengen, Ragnhild; Grøholt, Else-Karin; Hjelmesæth, Jøran; Strand, Bjørn Heine; Meyer, Haakon E

2013-09-12

International research has demonstrated that rural residency is a risk factor for childhood adiposity. The main aim of this study was to investigate the urban-rural gradient in overweight and obesity and whether the association differed by maternal education. Height, weight and waist circumference (WC) were measured in a nationally representative sample of 3166 Norwegian eight-year-olds in 2010. Anthropometric measures were stratified by area of residence (urbanity) and maternal education. Risk estimates for overweight (including obesity) and waist-to-height ratio ≥0.5 were calculated by log-binomial regression. Mean BMI and WC and risk estimates of overweight (including obesity) and waist-to-height ratio ≥0.5 were associated with both urbanity and maternal education. These associations were robust after mutual adjustment for each other. Furthermore, there was an indication of interaction between urbanity and maternal education, as trends of mean BMI and WC increased from urban to rural residence among children of low-educated mothers (p = 0.01 for both BMI and WC), whereas corresponding trends for children from higher educational background were non-significant (p > 0.30). However, formal tests of the interaction term urbanity by maternal education were non-significant (p-value for interaction was 0.29 for BMI and 0.31 for WC). In this nationally representative study, children living rurally and children of low-educated mothers had higher mean BMI and waist circumference than children living in more urban areas and children of higher educated mothers.

[Associated factors to availability and use of electronic media in children from preschool to 4th grade].

PubMed

Camargo, Diana Marina; Orozco, Luis Carlos

2013-01-01

The increased availability of electronic media has changed the behavior in children and young people by encouraging sedentary lifestile, with health effects from a very young age. To characterize the availability and use of electronic media and its associated factors in children from preschool through 4 th grade. A cross-sectional study with cluster sampling was carried out. Parents filled out the demographic survey, the availability and use of electronic media at home and in the child´s room. Log-binomial regression models were applied to estimate prevalence ratios adjusted for the sampling. Seven hundred and ten parents answered. The average age of the children was 6.7 years and 49.7% were male. Factors such as the mother working out of the house and family income were positively associated with the availability of electronic media at home and in the child´s room. The availability of a TV, computer and console in the child´s room, contributes to longer use of these electronic media. Both, the male gender and age of the child, were positively associated with the availability and use of electronic media. This is the first study in Colombia that reports the availability and use of electronic media in children. It is clear that modern life encourages sedentary behavior from the earliest years of life, which has been associated with health problems from early childhood. Intervention studies are needed aimed at reducing these behaviors in our context.

Association Between Age at Menarche and Gestational Diabetes Mellitus: The Australian Longitudinal Study on Women's Health.

PubMed

Schoenaker, Danielle A J M; Mishra, Gita D

2017-04-01

In this study, we aimed to examine the association between age at menarche and gestational diabetes mellitus (GDM). Data were from 4,749 women participating in the Australian Longitudinal Study on Women's Health between 2000 and 2012. Age at menarche was reported at baseline in 2000 when women were aged 22-27 years. During 12 years of follow-up, information on GDM diagnosis was obtained for each live birth. Log-binomial regression analysis was used to estimate relative risks and 95% confidence intervals. Analyses adjusted for mother's highest completed educational qualification, nulliparity, polycystic ovary syndrome, physical activity, and body mass index. Mean age at menarche was 12.9 years (standard deviation, 1.4). A first diagnosis of GDM was reported by 357 women (7.5%). Compared with women with menarche at age 13 years, women who had their first menstruation at age ≤11 years had a 51% higher risk of developing GDM (95% confidence interval: 1.10, 2.07) after adjustment for GDM risk factors. Our findings indicate that a young age at menarche may identify women at higher risk of GDM. Further prospective studies are needed to confirm our findings and to elucidate the role of early-life exposures in age at menarche and subsequent GDM risk. © The Author 2017. 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.

No evidence for cross-protection of the HPV-16/18 vaccine against HPV-6/11 positivity in female STI clinic visitors.

PubMed

Woestenberg, Petra J; King, Audrey J; van der Sande, Marianne A B; Donken, Robine; Leussink, Suzan; van der Klis, Fiona R M; Hoebe, Christian J P A; Bogaards, Johannes A; van Benthem, Birgit H B

2017-04-01

Data from a vaccine trial and from post-vaccine surveillance in the United Kingdom have suggested that the bivalent HPV-16/18 vaccine offers cross-protection against HPV-6/11 and protection against anogenital warts (AGW). We studied the effect of the bivalent vaccine on genital HPV-6/11 positivity and AGW in the Netherlands. We included all vaccine-eligible women from the PASSYON study, a biennial cross-sectional study among 16- to 24-year-old sexually transmitted infection (STI) clinic attendants. Vaginal self-swabs were analyzed for type specific HPV and AGW were diagnosed at the STI-clinic. Prevalence of HPV-6 and/or HPV-11 and AGW were compared between self-reported vaccinated and unvaccinated women by log-binomial regression analysis, adjusted for demographics and risk behavior. Of the 1198 women included, 56% reported to be vaccinated at least once. Relative to unvaccinated women, the adjusted prevalence ratio (PR) for HPV-6/11 was 1.03 (95% confidence interval [CI] 0.74-1.43) for women vaccinated at least once. The crude PR for AGW was 0.67 (95% CI 0.22-2.07) for women vaccinated at least once. Adjustment did not change these results. We observed no cross-protective effect of the bivalent vaccine on genital HPV-6/11 positivity and a non-significant partially protective effect on AGW. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Clashing paradigms: an empirical examination of cultural proxies and socioeconomic condition shaping Latino health.

PubMed

Echeverría, Sandra E; Pentakota, Sri Ram; Abraído-Lanza, Ana F; Janevic, Teresa; Gundersen, Daniel A; Ramirez, Sarah M; Delnevo, Cristine D

2013-10-01

Much debate exists regarding the role of culture versus socioeconomic position in shaping the health of Latino populations. We propose that both may matter for health and explicitly test their independent and joint effects on smoking and physical activity. We used the 2010 National Health Interview Survey, a population-based survey of the U.S. population, to estimate the prevalence of smoking and physical activity by language use (cultural proxy) and education among Latino adults (n = 4929). We fit log binomial regression models to estimate prevalence ratios and test for interaction. English-language use and educational attainment were each independently associated with smoking and physical activity. Joint effect models showed that individuals with both greater use of the English language and low levels of education were nearly three times more likely to smoke (prevalence ratio, 2.59; 95% confidence interval, 1.83-3.65) than those with low English language use and high education (referent group); high acculturation and high education were jointly associated with increased activity (prevalence ratio 2.24, 95% confidence interval, 1.79-2.81). Cultural proxies such as language use and educational attainment are both important determinants of health among Latinos. Their joint effect suggests the need to simultaneously consider Latinos' socioeconomic position and their increased risk of adopting health-damaging behaviors while addressing culturally-specific factors that may mitigate risk. Copyright © 2013 Elsevier Inc. All rights reserved.

Activity space-based measures of the food environment and their relationships to food purchasing behaviours for young urban adults in Canada.

PubMed

Widener, Michael J; Minaker, Leia M; Reid, Jessica L; Patterson, Zachary; Ahmadi, Tara Kamal; Hammond, David

2018-03-16

To examine the potential links between activity spaces, the food retail environment and food shopping behaviours for the population of young, urban adults. Participants took part in the Canada Food Study, which collected information on demographics, food behaviour, diet and health, as well as an additional smartphone study that included a seven-day period of logging GPS (global positioning system) location and food purchases. Using a time-weighted, continuous representation of participant activity spaces generated from GPS trajectory data, the locations of food purchases and a geocoded food retail data set, negative binomial regression models were used to explore what types of food retailers participants were exposed to and where food purchases were made. Toronto, Montreal, Vancouver, Edmonton and Halifax, Canada. Young adults aged 16-30 years (n 496). These participants were a subset of the larger Canada Food Study. Demographics, household food shopper status and city of residence were significantly associated with different levels of exposure to various types of food retailers. Food shopping behaviours were also statistically significantly associated with demographics, the activity space-based food environment, self-reported health and city of residence. The study confirms that food behaviours are related to activity space-based food environment measures, which provide a more comprehensive accounting of food retail exposure than home-based measures. In addition, exposure to food retail and food purchasing behaviours of an understudied population are described.

Drug use Discrimination Predicts Formation of High-Risk Social Networks: Examining Social Pathways of Discrimination.

PubMed

Crawford, Natalie D; Ford, Chandra; Rudolph, Abby; Kim, BoRin; Lewis, Crystal M

2017-09-01

Experiences of discrimination, or social marginalization and ostracism, may lead to the formation of social networks characterized by inequality. For example, those who experience discrimination may be more likely to develop drug use and sexual partnerships with others who are at increased risk for HIV compared to those without experiences of discrimination. This is critical as engaging in risk behaviors with others who are more likely to be HIV positive can increase one's risk of HIV. We used log-binomial regression models to examine the relationship between drug use, racial and incarceration discrimination with changes in the composition of one's risk network among 502 persons who use drugs. We examined both absolute and proportional changes with respect to sex partners, drug use partners, and injecting partners, after accounting for individual risk behaviors. At baseline, participants were predominately male (70%), black or Latino (91%), un-married (85%), and used crack (64%). Among those followed-up (67%), having experienced discrimination due to drug use was significantly related to increases in the absolute number of sex networks and drug networks over time. No types of discrimination were related to changes in the proportion of high-risk network members. Discrimination may increase one's risk of HIV acquisition by leading them to preferentially form risk relationships with higher-risk individuals, thereby perpetuating racial and ethnic inequities in HIV. Future social network studies and behavioral interventions should consider whether social discrimination plays a role in HIV transmission.

[Repeated pregnancy among adolescents and social vulnerability in Rio de Janeiro (RJ, Brazil): data analysis of Information System on Live Births].

PubMed

da Silva, Katia Silveira; Rozenberg, Riva; Bonan, Claudia; Chuva, Vânia Cristina Costa; da Costa, Simoni Furtado; Gomes, Maria Auxiliadora de Souza Mendes

2011-05-01

Repeated pregnancy (RP) among adolescents is seldom researched in Brazil, even tough the debate on the reproductive rights is important for this extract of population. A transversal study was developed with data from the Declaration of Live Births of adolescent mothers, living in Rio de Janeiro (RJ, Brazil), in 2005. The aim was to estimate the magnitude and features associated with RP. Prevalence ratios (PR) of RP, with 95% confidence interval (CI) for selected variables, were estimated through log-binomial multivariate regression. Among 12,168 adolescents, a RP prevalence of 29.1% was identified and the principal factors associated were: age 15-19 anos (PR=5.42; RI 95% 3.72-7.81); not doing prenatal consultation (RP=2.36; CI 95% 2.16-2.58); educational status<4 anos (PR=1.48; CI 95% 1.25-1.76); housewife job (PR=1.8; CI 95% 1.57-2.15) or other (PR=1.9; CI 95%; 1.73-2.10). Giving birth by cesarean section and low birth weight were negatively associated to repeated pregnancy with RP equal to 0,94 (CI 95%; 0,86-0,99) and 0.69 (CI 95%; 0.62-0.77). The adolescents with RP had worst socioeconomic and assistance indicators than those on their first pregnancy. Specific social policies for adolescent mothers, in vulnerable situation, will enable them to have better conditions to exercise their reproductive rights.

Practice and attitudes regarding double gloving among staff surgeons and surgical trainees.

PubMed

Lipson, Mark E; Deardon, Rob; Switzer, Noah J; de Gara, Chris; Ball, Chad G; Grondin, Sean C

2018-06-01

Despite supporting evidence, many staff surgeons and surgical trainees do not routinely double glove. We performed a study to assess rates of and attitudes toward double gloving and the use of eye protection in the operating room. We conducted an electronic survey among all staff surgeons and surgical trainees at 2 tertiary care centres in Alberta between September and November 2015.We analyzed the data using log-binomial regression for binary outcomes to account for multiple independent variables and interactions. For 2-group comparisons, we used a 2-group test of proportions. The response rate was 34.3% (361/1051); 205/698 staff surgeons (29.4%) and 156/353 surgical trainees (44.2%) responded. Trainees were more likely than staff surgeons to ever double glove in the operating room ( p = 0.01) and to do so routinely ( p = 0.01). Staff surgeons were more likely than trainees to never double glove ( p = 0.01). A total of 300/353 respondents (85.0%) reported using eye protection routinely in the operating room. Needle-stick injury was common (184 staff surgeons [92.5%], 115 trainees [74.7%]). Reduced tactile feedback, decreased manual dexterity and discomfort/poor fit were perceived barriers to double gloving. Rates of double gloving leave room for improvement. Surgical trainees were more likely than staff surgeons to double glove. Barriers remain to routine double gloving among staff surgeons and trainees. Increased education on the benefits of double gloving and early introduction of this practice may increase uptake.

Factors associated with the over-treatment and under-treatment of gonorrhea and chlamydia in adolescents presenting to a public hospital emergency department.

PubMed

Anaene, Mutimbwa; Soyemi, Kenneth; Caskey, Rachel

2016-12-01

The purpose of this study was to measure the prevalence of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) and the rates and factors associated with their over-treatment (OT) and under-treatment (UT). A retrospective chart review was performed of patients aged 13-24 years who were screened for GC/CT in the emergency department (ED) of a public hospital. Descriptive statistics were obtained for all variables, and multivariate log binomial regression was performed to ascertain the factors associated with OT and UT. Seven hundred and ninety-seven adolescents and young adults were screened for GC/CT. The overall sexually transmitted infection (STI) positivity rate was 21.6%; 136 (21.6%) subjects were over-treated and 74 (43.4%) subjects were under-treated. Patients presenting with STI exposure or genito-urinary symptoms were more likely to be OT. Additionally, females aged 18-19 years or with a prior history of STIs were more likely to be OT. Females (83.6%) were more likely to be UT, while STI exposure, genito-urinary symptoms, and a prior history of STI were protective of UT . Adolescents and young adults screened for STIs have a high prevalence of GC/CT. A significant proportion of these patients end up over-treated and an even higher proportion are under-treated. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Maternal veterinary occupation and adverse birth outcomes in Washington State, 1992-2014: a population-based retrospective cohort study.

PubMed

Meisner, Julianne; Vora, Manali V; Fuller, Mackenzie S; Phipps, Amanda I; Rabinowitz, Peter M

2018-05-01

Women in veterinary occupations are routinely exposed to potential reproductive hazards, yet research into their birth outcomes is limited. We conducted a population-based retrospective cohort study of the association between maternal veterinary occupation and adverse birth outcomes. Using Washington State birth certificate, fetal death certificate and hospital discharge data from 1992 to 2014, we compared birth outcomes of mothers in veterinary professions (n=2662) with those in mothers in dental professions (n=10 653) and other employed mothers (n=8082). Relative risks (RRs) and 95% CIs were estimated using log binomial regression. Outcomes studied were premature birth (<37 weeks), small for gestational age (SGA), malformations and fetal death (death at ≥20 weeks gestation). Subgroup analyses evaluated risk of these outcomes among veterinarians and veterinary support staff separately. While no statistically significant associations were found, we noted a trend for SGA births in all veterinary mothers compared with dental mothers (RR=1.16, 95% CI 0.99 to 1.36) and in veterinarians compared with other employed mothers (RR=1.37, 95% CI 0.96 to 1.96). Positive but non-significant association was found for malformations among children of veterinary support staff. These results support the need for further study of the association between veterinary occupation and adverse birth outcomes. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

[Spatial epidemiological study on malaria epidemics in Hainan province].

PubMed

Wen, Liang; Shi, Run-He; Fang, Li-Qun; Xu, De-Zhong; Li, Cheng-Yi; Wang, Yong; Yuan, Zheng-Quan; Zhang, Hui

2008-06-01

To better understand the characteristics of spatial distribution of malaria epidemics in Hainan province and to explore the relationship between malaria epidemics and environmental factors, as well to develop prediction model on malaria epidemics. Data on Malaria and meteorological factors were collected in all 19 counties in Hainan province from May to Oct., 2000, and the proportion of land use types of these counties in this period were extracted from digital map of land use in Hainan province. Land surface temperatures (LST) were extracted from MODIS images and elevations of these counties were extracted from DEM of Hainan province. The coefficients of correlation of malaria incidences and these environmental factors were then calculated with SPSS 13.0, and negative binomial regression analysis were done using SAS 9.0. The incidence of malaria showed (1) positive correlations to elevation, proportion of forest land area and grassland area; (2) negative correlations to the proportion of cultivated area, urban and rural residents and to industrial enterprise area, LST; (3) no correlations to meteorological factors, proportion of water area, and unemployed land area. The prediction model of malaria which came from negative binomial regression analysis was: I (monthly, unit: 1/1,000,000) = exp (-1.672-0.399xLST). Spatial distribution of malaria epidemics was associated with some environmental factors, and prediction model of malaria epidemic could be developed with indexes which extracted from satellite remote sensing images.

The gap between suicide characteristics in the print media and in the population.

PubMed

Niederkrotenthaler, Thomas; Till, Benedikt; Herberth, Arno; Voracek, Martin; Kapusta, Nestor D; Etzersdorfer, Elmar; Strauss, Markus; Sonneck, Gernot

2009-08-01

Programmes to educate media professionals about suicide are increasingly established, but information about which suicide cases are most likely to be reported in the mass media is sparse. We applied binomial tests to compare frequencies of social characteristics of all domestic suicides in the 13 largest Austrian print media in 2005 with frequencies of suicide characteristics in the population. Additionally, each reported suicide case was linked to its respective entry in the suicide database. We performed a logistic regression analysis, with presence of an article as outcome, and sex of the suicide case, age, religious affiliation, family status, conduction of an autopsy and location of the suicide as explaining variables. Time of the year and federal state where the suicide happened was controlled for. Binomial tests showed that suicides involving murder or murder attempt were over-represented in the media. Reporting on mental disorders was under-represented. In the regression analysis, the likelihood of a report was negatively associated with the age of suicide cases. Foreign citizenship was a further predictor of a suicide report. The methods of drowning, jumping, shooting and rare methods were more likely to be reported than hanging, which is the most frequent suicide method in Austria. Suicide characteristics in the media are not representative of the population. The identified discrepancies provide a basis for tailor-made education of mass media professionals.

Self-harm amongst people of Chinese origin versus White people living in England: a cohort study.

PubMed

Chang, Shu-Sen; Steeg, Sarah; Kapur, Navneet; Webb, Roger T; Yip, Paul S F; Cooper, Jayne

2015-04-14

There has been little previous research on self-harm among people of Chinese origin living in the UK, although this population has grown substantially in recent years and China is now the largest source of international students at UK universities. We conducted a prospective cohort study using self-harm presentation data (1997-2011) collected from three hospitals in the City of Manchester, which has the largest Chinese population across all UK Local Authorities. Rate ratios between the Chinese and White groups were calculated using Poisson regression models. Chi-square tests (or Fisher's exact tests), logistic regression, and log-binomial regression were used to examine differences in characteristics and clinical management between groups. Ethnicity was known in the study cohort for 23,297 (87%) amongst 26,894 individuals aged 15 years and above. A total number of 97/23,297 (0.4%) people of Chinese ethnic origin presented with self-harm over the study period and 20,419 (88%) were White people. Incidence of self-harm in the Chinese group (aged 16-64 years) was less than one fifth of that found in White people (0.6 versus 3.2 per 1000 person-years; rate ratio 0.18, 95% confidence interval 0.13-0.24), and was particularly low amongst men of Chinese origin. Individuals of Chinese origin who presented with self-harm were younger, more likely to be female and students, and more likely to self-injure and describe relationship problems as a precipitant than White people. They were less likely to have clinical risk factors such as drug/alcohol misuse and receiving psychiatric treatment, and were rated to have lower risk of self-harm repetition by treating clinicians. Future research needs to investigate whether the low incidence of self-harm presenting to hospitals amongst people of Chinese origin truly reflects a lower frequency of self-harm, or alternatively is due to markedly different post-episode help-seeking behaviours or student overrepresentation in this ethnic group. Relevant healthcare professionals need to be aware of the risk characteristics of people of Chinese origin who self-harm.

Association of stressful life events with accelerated bone loss in older men: the Osteoporotic Fractures in Men (MrOS) Study

PubMed Central

Fink, Howard A.; Kuskowski, Michael A.; Cauley, Jane A.; Taylor, Brent C.; Schousboe, John T.; Cawthon, Peggy M.; Ensrud, Kristine E.

2015-01-01

Purpose/Introduction Prior studies suggest that stressful life events may increase adverse health outcomes, including falls and possibly fractures. The current study builds on these findings and examines whether stressful life events are associated with increased bone loss. Methods 4388 men aged ≥65 years in the Osteoporotic Fractures in Men study completed total hip bone mineral density (BMD) measures at baseline and visit 2, approximately 4.6 years later, and self-reported stressful life events data mid-way between baseline and visit 2, and at visit 2. We used linear regression to model the association of stressful life events with concurrent annualized total hip BMD loss, and log binomial regression or Poisson regression to model risk of concurrent accelerated BMD loss (>1 SD more than mean annualized change). Results 75.3% of men reported ≥1 type of stressful life event, including 43.3% with ≥2 types of stressful life events. Mean annualized BMD loss was −0.36% (SD 0.88) and 13.9% of men were categorized with accelerated BMD loss (about 5.7% or more total loss). Rate of annualized BMD loss increased with the number of types of stressful life events after adjustment for age (p<0.001), but not after multivariable adjustment (p=0.07). Multivariable-adjusted risk of accelerated BMD loss increased with the number of types of stressful life events (RR, 1.10 [95% CI, 1.04–1.16]) per increase of 1 type of stressful life event). Fracture risk was not significantly different between stressful life event-accelerated bone loss subgroups (p=0.08). Conclusions In these older men, stressful life events were associated with a small, dose-related increase in risk of concurrent accelerated hip bone loss. Low frequency of fractures limited assessment of whether rapid bone loss mediates any association of stressful life events with incident fractures. Future studies are needed to confirm these findings and to investigate the mechanism that may underlie this association. PMID:25169421

Early Warning Signals of Financial Crises with Multi-Scale Quantile Regressions of Log-Periodic Power Law Singularities

PubMed Central

Zhang, Qun; Zhang, Qunzhi; Sornette, Didier

2016-01-01

We augment the existing literature using the Log-Periodic Power Law Singular (LPPLS) structures in the log-price dynamics to diagnose financial bubbles by providing three main innovations. First, we introduce the quantile regression to the LPPLS detection problem. This allows us to disentangle (at least partially) the genuine LPPLS signal and the a priori unknown complicated residuals. Second, we propose to combine the many quantile regressions with a multi-scale analysis, which aggregates and consolidates the obtained ensembles of scenarios. Third, we define and implement the so-called DS LPPLS Confidence™ and Trust™ indicators that enrich considerably the diagnostic of bubbles. Using a detailed study of the “S&P 500 1987” bubble and presenting analyses of 16 historical bubbles, we show that the quantile regression of LPPLS signals contributes useful early warning signals. The comparison between the constructed signals and the price development in these 16 historical bubbles demonstrates their significant predictive ability around the real critical time when the burst/rally occurs. PMID:27806093

High-throughput determination of octanol/water partition coefficients using a shake-flask method and novel two-phase solvent system.

PubMed

Morikawa, Go; Suzuka, Chihiro; Shoji, Atsushi; Shibusawa, Yoichi; Yanagida, Akio

2016-01-05

A high-throughput method for determining the octanol/water partition coefficient (P(o/w)) of a large variety of compounds exhibiting a wide range in hydrophobicity was established. The method combines a simple shake-flask method with a novel two-phase solvent system comprising an acetonitrile-phosphate buffer (0.1 M, pH 7.4)-1-octanol (25:25:4, v/v/v; AN system). The AN system partition coefficients (K(AN)) of 51 standard compounds for which log P(o/w) (at pH 7.4; log D) values had been reported were determined by single two-phase partitioning in test tubes, followed by measurement of the solute concentration in both phases using an automatic flow injection-ultraviolet detection system. The log K(AN) values were closely related to reported log D values, and the relationship could be expressed by the following linear regression equation: log D=2.8630 log K(AN) -0.1497(n=51). The relationship reveals that log D values (+8 to -8) for a large variety of highly hydrophobic and/or hydrophilic compounds can be estimated indirectly from the narrow range of log K(AN) values (+3 to -3) determined using the present method. Furthermore, log K(AN) values for highly polar compounds for which no log D values have been reported, such as amino acids, peptides, proteins, nucleosides, and nucleotides, can be estimated using the present method. The wide-ranging log D values (+5.9 to -7.5) of these molecules were estimated for the first time from their log K(AN) values and the above regression equation. Copyright © 2015 Elsevier B.V. All rights reserved.

Dental enamel defects, caries experience and oral health-related quality of life: a cohort study.

PubMed

Arrow, P

2017-06-01

The impact of enamel defects of the first permanent molars on caries experience and child oral health-related quality of life was evaluated in a cohort study. Children who participated in a study of enamel defects of the first permanent molars 8 years earlier were invited for a follow-up assessment. Consenting children completed the Child Perception Questionnaire and the faces Modified Child Dental Anxiety Scale, and were examined by two calibrated examiners. ANOVA, Kruskal-Wallis, negative binomial and logistic regression were used for data analyses. One hundred and eleven children returned a completed questionnaire and 91 were clinically examined. Negative binomial regression found that oral health impacts were associated with gender (boys, risk ratio (RR) = 0.73, P = 0.03) and decayed, missing or filled permanent teeth (DMFT) (RR = 1.1, P = 0.04). The mean DMFT of children were sound (0.9, standard deviation (SD) = 1.4), diffuse defects (0.8, SD = 1.7), demarcated defects (1.5, SD = 1.4) and pit defects (1.3, SD = 2.3) (Kruskal-Wallis, P = 0.05). Logistic regression of first permanent molar caries found higher odds of caries experience with baseline primary tooth caries experience (odds ratio (OR) = 1.5, P = 0.01), the number of teeth affected by enamel defects (OR = 1.9, P = 0.05) and lower odds with the presence of diffuse enamel defects (OR = 0.1, P = 0.04). The presence of diffuse enamel defects was associated with lower odds of caries experience. © 2016 Australian Dental Association.

Multivariate random-parameters zero-inflated negative binomial regression model: an application to estimate crash frequencies at intersections.

PubMed

Dong, Chunjiao; Clarke, David B; Yan, Xuedong; Khattak, Asad; Huang, Baoshan

2014-09-01

Crash data are collected through police reports and integrated with road inventory data for further analysis. Integrated police reports and inventory data yield correlated multivariate data for roadway entities (e.g., segments or intersections). Analysis of such data reveals important relationships that can help focus on high-risk situations and coming up with safety countermeasures. To understand relationships between crash frequencies and associated variables, while taking full advantage of the available data, multivariate random-parameters models are appropriate since they can simultaneously consider the correlation among the specific crash types and account for unobserved heterogeneity. However, a key issue that arises with correlated multivariate data is the number of crash-free samples increases, as crash counts have many categories. In this paper, we describe a multivariate random-parameters zero-inflated negative binomial (MRZINB) regression model for jointly modeling crash counts. The full Bayesian method is employed to estimate the model parameters. Crash frequencies at urban signalized intersections in Tennessee are analyzed. The paper investigates the performance of MZINB and MRZINB regression models in establishing the relationship between crash frequencies, pavement conditions, traffic factors, and geometric design features of roadway intersections. Compared to the MZINB model, the MRZINB model identifies additional statistically significant factors and provides better goodness of fit in developing the relationships. The empirical results show that MRZINB model possesses most of the desirable statistical properties in terms of its ability to accommodate unobserved heterogeneity and excess zero counts in correlated data. Notably, in the random-parameters MZINB model, the estimated parameters vary significantly across intersections for different crash types. Copyright © 2014 Elsevier Ltd. All rights reserved.

New diagnostic index for sarcopenia in patients with cardiovascular diseases

PubMed Central

Kai, Hisashi; Shibata, Rei; Niiyama, Hiroshi; Nishiyama, Yasuhiro; Murohara, Toyoaki; Yoshida, Noriko; Katoh, Atsushi; Ikeda, Hisao

2017-01-01

Background Sarcopenia is an aging and disease-related syndrome characterized by progressive and generalized loss of skeletal muscle mass and strength, with the risk of frailty and poor quality of life. Sarcopenia is diagnosed by a decrease in skeletal muscle index (SMI) and reduction of either handgrip strength or gait speed. However, measurement of SMI is difficult for general physicians because it requires special equipment for bioelectrical impedance assay or dual-energy X-ray absorptiometry. The purpose of this study was, therefore, to explore a novel, simple diagnostic method of sarcopenia evaluation in patients with cardiovascular diseases (CVD). Methods We retrospectively investigated 132 inpatients with CVD (age: 72±12 years, age range: 27–93 years, males: 61%) Binomial logistic regression and correlation analyses were used to assess the associations of sarcopenia with simple physical data and biomarkers, including muscle-related inflammation makers and nutritional markers. Results Sarcopenia was present in 29.5% of the study population. Serum concentrations of adiponectin and sialic acid were significantly higher in sarcopenic than non-sarcopenic CVD patients. Stepwise multivariate binomial logistic regression analysis revealed that adiponectin, sialic acid, sex, age, and body mass index were independent factors for sarcopenia detection. Sarcopenia index, obtained from the diagnostic regression formula for sarcopenia detection including the five independent factors, indicated a high accuracy in ROC curve analysis (sensitivity 94.9%, specificity 69.9%) and the cutoff value for sarcopenia detection was -1.6134. Sarcopenia index had a significant correlation with the conventional diagnostic parameters of sarcopenia. Conclusions Our new sarcopenia index using simple parameters would be useful for diagnosing sarcopenia in CVD patients. PMID:28542531

Factors associated with dental caries in a group of American Indian children at age 36 months.

PubMed

Warren, John J; Blanchette, Derek; Dawson, Deborah V; Marshall, Teresa A; Phipps, Kathy R; Starr, Delores; Drake, David R

2016-04-01

Early childhood caries (ECC) is rampant among American Indian children, but there has been relatively little study of this problem. This article reports on risk factors for caries for a group of American Indian children at age 36 months as part of a longitudinal study. Pregnant women from a Northern Plains Tribal community were recruited to participate in a longitudinal study of caries and caries risk factors. Standardized dental examinations were completed on children, and questionnaires were completed by mothers at baseline and when children were 4, 8, 12, 16, 22, 28, and 36 months of age. Examinations were surface-specific for dental caries, and the questionnaires collected data on demographic, dietary, and behavioral factors. Nonparametric bivariate tests and logistic regression models were used to identify risk factors for caries at 36 months, and negative binomial regression was used to identify factors related to caries severity (dmf counts). Among the 232 children, and caries prevalence for cavitated lesions was 80%, with an additional 15% having only noncavitated lesions. The mean dmfs was 9.6, and of the total dmfs, nearly 62% of affected surfaces were decayed, 31% were missing, and 7% were filled. Logistic regression identified higher added-sugar beverage consumption, younger maternal age at baseline, higher maternal DMFS at baseline, and greater number of people in the household as significant (P < 0.05) risk factors. Negative binomial regression found that only maternal DMFS was associated with child dmf counts. By the age of 36 months, dental caries is nearly universal in this population of American Indian children. Caries risk factors included sugared beverage consumption, greater household size, and maternal factors, but further analyses are needed to better understand caries in this population. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Three-parameter modeling of the soil sorption of acetanilide and triazine herbicide derivatives.

PubMed

Freitas, Mirlaine R; Matias, Stella V B G; Macedo, Renato L G; Freitas, Matheus P; Venturin, Nelson

2014-02-01

Herbicides have widely variable toxicity and many of them are persistent soil contaminants. Acetanilide and triazine family of herbicides have widespread use, but increasing interest for the development of new herbicides has been rising to increase their effectiveness and to diminish environmental hazard. The environmental risk of new herbicides can be accessed by estimating their soil sorption (logKoc), which is usually correlated to the octanol/water partition coefficient (logKow). However, earlier findings have shown that this correlation is not valid for some acetanilide and triazine herbicides. Thus, easily accessible quantitative structure-property relationship models are required to predict logKoc of analogues of the these compounds. Octanol/water partition coefficient, molecular weight and volume were calculated and then regressed against logKoc for two series of acetanilide and triazine herbicides using multiple linear regression, resulting in predictive and validated models.

Delineating chalk sand distribution of Ekofisk formation using probabilistic neural network (PNN) and stepwise regression (SWR): Case study Danish North Sea field

NASA Astrophysics Data System (ADS)

Haris, A.; Nafian, M.; Riyanto, A.

2017-07-01

Danish North Sea Fields consist of several formations (Ekofisk, Tor, and Cromer Knoll) that was started from the age of Paleocene to Miocene. In this study, the integration of seismic and well log data set is carried out to determine the chalk sand distribution in the Danish North Sea field. The integration of seismic and well log data set is performed by using the seismic inversion analysis and seismic multi-attribute. The seismic inversion algorithm, which is used to derive acoustic impedance (AI), is model-based technique. The derived AI is then used as external attributes for the input of multi-attribute analysis. Moreover, the multi-attribute analysis is used to generate the linear and non-linear transformation of among well log properties. In the case of the linear model, selected transformation is conducted by weighting step-wise linear regression (SWR), while for the non-linear model is performed by using probabilistic neural networks (PNN). The estimated porosity, which is resulted by PNN shows better suited to the well log data compared with the results of SWR. This result can be understood since PNN perform non-linear regression so that the relationship between the attribute data and predicted log data can be optimized. The distribution of chalk sand has been successfully identified and characterized by porosity value ranging from 23% up to 30%.

Non-Asymptotic Oracle Inequalities for the High-Dimensional Cox Regression via Lasso.

PubMed

Kong, Shengchun; Nan, Bin

2014-01-01

We consider finite sample properties of the regularized high-dimensional Cox regression via lasso. Existing literature focuses on linear models or generalized linear models with Lipschitz loss functions, where the empirical risk functions are the summations of independent and identically distributed (iid) losses. The summands in the negative log partial likelihood function for censored survival data, however, are neither iid nor Lipschitz.We first approximate the negative log partial likelihood function by a sum of iid non-Lipschitz terms, then derive the non-asymptotic oracle inequalities for the lasso penalized Cox regression using pointwise arguments to tackle the difficulties caused by lacking iid Lipschitz losses.

Non-Asymptotic Oracle Inequalities for the High-Dimensional Cox Regression via Lasso

PubMed Central

Kong, Shengchun; Nan, Bin

2013-01-01

We consider finite sample properties of the regularized high-dimensional Cox regression via lasso. Existing literature focuses on linear models or generalized linear models with Lipschitz loss functions, where the empirical risk functions are the summations of independent and identically distributed (iid) losses. The summands in the negative log partial likelihood function for censored survival data, however, are neither iid nor Lipschitz.We first approximate the negative log partial likelihood function by a sum of iid non-Lipschitz terms, then derive the non-asymptotic oracle inequalities for the lasso penalized Cox regression using pointwise arguments to tackle the difficulties caused by lacking iid Lipschitz losses. PMID:24516328

Green lumber grade yields from black cherry and red maple factory grade logs sawed at band and circular mills

Treesearch

Daniel A. Yaussy

1989-01-01

Multivariate regression models were developed to predict green board-foot yields (1 board ft. = 2.360 dm 3) for the standard factory lumber grades processed from black cherry (Prunus serotina Ehrh.) and red maple (Acer rubrum L.) factory grade logs sawed at band and circular sawmills. The models use log...

Analyzing Log Files to Predict Students' Problem Solving Performance in a Computer-Based Physics Tutor

ERIC Educational Resources Information Center

Lee, Young-Jin

2015-01-01

This study investigates whether information saved in the log files of a computer-based tutor can be used to predict the problem solving performance of students. The log files of a computer-based physics tutoring environment called Andes Physics Tutor was analyzed to build a logistic regression model that predicted success and failure of students'…

The dependence of PGA and PGV on distance and magnitude inferred from Northern California ShakeMap data

USGS Publications Warehouse

Boatwright, J.; Bundock, H.; Luetgert, J.; Seekins, L.; Gee, L.; Lombard, P.

2003-01-01

We analyze peak ground velocity (PGV) and peak ground acceleration (PGA) data from 95 moderate (3.5 ??? M 100 km, the peak motions attenuate more rapidly than a simple power law (that is, r-??) can fit. Instead, we use an attenuation function that combines a fixed power law (r-0.7) with a fitted exponential dependence on distance, which is estimated as expt(-0.0063r) and exp(-0.0073r) for PGV and PGA, respectively, for moderate earthquakes. We regress log(PGV) and log(PGA) as functions of distance and magnitude. We assume that the scaling of log(PGV) and log(PGA) with magnitude can differ for moderate and large earthquakes, but must be continuous. Because the frequencies that carry PGV and PGA can vary with earthquake size for large earthquakes, the regression for large earthquakes incorporates a magnitude dependence in the exponential attenuation function. We fix the scaling break between moderate and large earthquakes at M 5.5; log(PGV) and log(PGA) scale as 1.06M and 1.00M, respectively, for moderate earthquakes and 0.58M and 0.31M for large earthquakes.

Distinguishing between Binomial, Hypergeometric and Negative Binomial Distributions

ERIC Educational Resources Information Center

Wroughton, Jacqueline; Cole, Tarah

2013-01-01

Recognizing the differences between three discrete distributions (Binomial, Hypergeometric and Negative Binomial) can be challenging for students. We present an activity designed to help students differentiate among these distributions. In addition, we present assessment results in the form of pre- and post-tests that were designed to assess the…

Library Book Circulation and the Beta-Binomial Distribution.

ERIC Educational Resources Information Center

Gelman, E.; Sichel, H. S.

1987-01-01

Argues that library book circulation is a binomial rather than a Poisson process, and that individual book popularities are continuous beta distributions. Three examples demonstrate the superiority of beta over negative binomial distribution, and it is suggested that a bivariate-binomial process would be helpful in predicting future book…

Early-Life Exposure to Outdoor Air Pollution and Respiratory Health, Ear Infections, and Eczema in Infants from the INMA Study

PubMed Central

Pedersen, Marie; Garcia-Esteban, Raquel; Ballester, Ferran; Basterrechea, Mikel; Esplugues, Ana; Fernández-Somoano, Ana; Lertxundi, Aitana; Tardón, Adonina; Sunyer, Jordi

2012-01-01

Background: Prenatal and early-life periods may be critical windows for harmful effects of air pollution on infant health. Objectives: We studied the association of air pollution exposure during pregnancy and the first year of life with respiratory illnesses, ear infections, and eczema during the first 12–18 months of age in a Spanish birth cohort of 2,199 infants. Methods: We obtained parentally reported information on doctor-diagnosed lower respiratory tract infections (LRTI) and parental reports of wheezing, eczema, and ear infections. We estimated individual exposures to nitrogen dioxide (NO2) and benzene with temporally adjusted land use regression models. We used log-binomial regression models and a combined random-effects meta-analysis to estimate the effects of air pollution exposure on health outcomes across the four study locations. Results: A 10-µg/m3 increase in average NO2 during pregnancy was associated with LRTI [relative risk (RR) = 1.05; 95% CI: 0.98, 1.12] and ear infections (RR = 1.18; 95% CI: 0.98, 1.41). The RRs for an interquartile range (IQR) increase in NO2 were 1.08 (95% CI: 0.97, 1.21) for LRTI and 1.31 (95% CI: 0.97, 1.76) for ear infections. Compared with NO2, the association for an IQR increase in average benzene exposure was similar for LRTI (RR = 1.06; 95% CI: 0.94, 1.19) and slightly lower for ear infections (RR = 1.17; 95% CI: 0.93, 1.46). Associations were slightly stronger among infants whose mothers spent more time at home during pregnancy. Air pollution exposure during the first year was highly correlated with prenatal exposure, so we were unable to discern the relative importance of each exposure period. Conclusions: Our findings support the hypothesis that early-life exposure to ambient air pollution may increase the risk of upper and lower respiratory tract infections in infants. PMID:23221880

Reducing lost to follow-up in a large clinical trial of prevention of mother-to-child transmission of HIV: The Breastfeeding, Antiretrovirals and Nutrition (BAN) study experience

PubMed Central

Sellers, Christopher J; Lee, Hana; Chasela, Charles; Kayira, Dumbani; Soko, Alice; Mofolo, Innocent; Ellington, Sascha; Hudgens, Michael G; Kourtis, Athena P; King, Caroline C; Jamieson, Denise J; van der Horst, Charles

2014-01-01

Background/Aims Retaining patients in prevention of mother-to-child transmission of HIV studies can be challenging in resource limited settings, where high lost to follow-up (LTFU) rates have been reported. In this paper, we describe the effectiveness of methods used to encourage retention in the Breastfeeding, Antiretrovirals, and Nutrition (BAN) study and analyze factors associated with LTFU in the study. Methods The BAN clinical trial was designed to evaluate the efficacy of 3 different mother-to-child HIV transmission prevention strategies. Lower than expected participant retention prompted enhanced efforts to reduce LTFU during the conduct of the trial. Following study completion, we employed regression modeling to determine predictors of perfect attendance and variables associated with being LTFU. Results During the study, intensive tracing efforts were initiated after the first 1686 mother-infant pairs had been enrolled, and 327 pairs were missing. Sixty of these pairs were located and had complete data obtained. Among the 683 participants enrolling after initiation of intensive tracing efforts, the LTFU rate was 3.4%. At study's end, 290 (12.2%) of the 2369 mother-infant pairs were LTFU. Among successfully traced missing pairs, relocation was common and three were deceased. Log-binomial regression modeling revealed higher maternal hemoglobin and older maternal age to be significant predictors of perfect attendance. These factors and the presence of food insecurity were also significantly associated with lower rates of LTFU. Conclusions In this large HIV prevention trial, intensive tracing efforts centered on reaching study participants at their homes succeeded in finding a substantial proportion of LTFU participants, and were very effective in preventing further LTFU during the remainder of the trial. The association between food insecurity and lower rates of LTFU is likely related to the study's provision of nutritional support, including a family maize supplement, which may have contributed to patient retention. PMID:25518956

Matching the Statistical Model to the Research Question for Dental Caries Indices with Many Zero Counts.

PubMed

Preisser, John S; Long, D Leann; Stamm, John W

2017-01-01

Marginalized zero-inflated count regression models have recently been introduced for the statistical analysis of dental caries indices and other zero-inflated count data as alternatives to traditional zero-inflated and hurdle models. Unlike the standard approaches, the marginalized models directly estimate overall exposure or treatment effects by relating covariates to the marginal mean count. This article discusses model interpretation and model class choice according to the research question being addressed in caries research. Two data sets, one consisting of fictional dmft counts in 2 groups and the other on DMFS among schoolchildren from a randomized clinical trial comparing 3 toothpaste formulations to prevent incident dental caries, are analyzed with negative binomial hurdle, zero-inflated negative binomial, and marginalized zero-inflated negative binomial models. In the first example, estimates of treatment effects vary according to the type of incidence rate ratio (IRR) estimated by the model. Estimates of IRRs in the analysis of the randomized clinical trial were similar despite their distinctive interpretations. The choice of statistical model class should match the study's purpose, while accounting for the broad decline in children's caries experience, such that dmft and DMFS indices more frequently generate zero counts. Marginalized (marginal mean) models for zero-inflated count data should be considered for direct assessment of exposure effects on the marginal mean dental caries count in the presence of high frequencies of zero counts. © 2017 S. Karger AG, Basel.

Matching the Statistical Model to the Research Question for Dental Caries Indices with Many Zero Counts

PubMed Central

Preisser, John S.; Long, D. Leann; Stamm, John W.

2017-01-01

Marginalized zero-inflated count regression models have recently been introduced for the statistical analysis of dental caries indices and other zero-inflated count data as alternatives to traditional zero-inflated and hurdle models. Unlike the standard approaches, the marginalized models directly estimate overall exposure or treatment effects by relating covariates to the marginal mean count. This article discusses model interpretation and model class choice according to the research question being addressed in caries research. Two datasets, one consisting of fictional dmft counts in two groups and the other on DMFS among schoolchildren from a randomized clinical trial (RCT) comparing three toothpaste formulations to prevent incident dental caries, are analysed with negative binomial hurdle (NBH), zero-inflated negative binomial (ZINB), and marginalized zero-inflated negative binomial (MZINB) models. In the first example, estimates of treatment effects vary according to the type of incidence rate ratio (IRR) estimated by the model. Estimates of IRRs in the analysis of the RCT were similar despite their distinctive interpretations. Choice of statistical model class should match the study’s purpose, while accounting for the broad decline in children’s caries experience, such that dmft and DMFS indices more frequently generate zero counts. Marginalized (marginal mean) models for zero-inflated count data should be considered for direct assessment of exposure effects on the marginal mean dental caries count in the presence of high frequencies of zero counts. PMID:28291962

Development of binomial sequential sampling plans for forecasting Listronotus maculicollis (Coleoptera: Curculionidae) larvae based on the relationship to adult counts and turfgrass damage.

PubMed

McGraw, Benjamin A; Koppenhöfer, Albrecht M

2009-06-01

Binomial sequential sampling plans were developed to forecast weevil Listronotus maculicollis Kirby (Coleoptera: Curculionidae), larval damage to golf course turfgrass and aid in the development of integrated pest management programs for the weevil. Populations of emerging overwintered adults were sampled over a 2-yr period to determine the relationship between adult counts, larval density, and turfgrass damage. Larval density and composition of preferred host plants (Poa annua L.) significantly affected the expression of turfgrass damage. Multiple regression indicates that damage may occur in moderately mixed P. annua stands with as few as 10 larvae per 0.09 m2. However, > 150 larvae were required before damage became apparent in pure Agrostis stolonifera L. plots. Adult counts during peaks in emergence as well as cumulative counts across the emergence period were significantly correlated to future densities of larvae. Eight binomial sequential sampling plans based on two tally thresholds for classifying infestation (T = 1 and two adults) and four adult density thresholds (0.5, 0.85, 1.15, and 1.35 per 3.34 m2) were developed to forecast the likelihood of turfgrass damage by using adult counts during peak emergence. Resampling for validation of sample plans software was used to validate sampling plans with field-collected data sets. All sampling plans were found to deliver accurate classifications (correct decisions were made between 84.4 and 96.8%) in a practical timeframe (average sampling cost < 22.7 min).

Accounting for non-independent detection when estimating abundance of organisms with a Bayesian approach

USGS Publications Warehouse

Martin, Julien; Royle, J. Andrew; MacKenzie, Darryl I.; Edwards, Holly H.; Kery, Marc; Gardner, Beth

2011-01-01

Summary 1. Binomial mixture models use repeated count data to estimate abundance. They are becoming increasingly popular because they provide a simple and cost-effective way to account for imperfect detection. However, these models assume that individuals are detected independently of each other. This assumption may often be violated in the field. For instance, manatees (Trichechus manatus latirostris) may surface in turbid water (i.e. become available for detection during aerial surveys) in a correlated manner (i.e. in groups). However, correlated behaviour, affecting the non-independence of individual detections, may also be relevant in other systems (e.g. correlated patterns of singing in birds and amphibians). 2. We extend binomial mixture models to account for correlated behaviour and therefore to account for non-independent detection of individuals. We simulated correlated behaviour using beta-binomial random variables. Our approach can be used to simultaneously estimate abundance, detection probability and a correlation parameter. 3. Fitting binomial mixture models to data that followed a beta-binomial distribution resulted in an overestimation of abundance even for moderate levels of correlation. In contrast, the beta-binomial mixture model performed considerably better in our simulation scenarios. We also present a goodness-of-fit procedure to evaluate the fit of beta-binomial mixture models. 4. We illustrate our approach by fitting both binomial and beta-binomial mixture models to aerial survey data of manatees in Florida. We found that the binomial mixture model did not fit the data, whereas there was no evidence of lack of fit for the beta-binomial mixture model. This example helps illustrate the importance of using simulations and assessing goodness-of-fit when analysing ecological data with N-mixture models. Indeed, both the simulations and the goodness-of-fit procedure highlighted the limitations of the standard binomial mixture model for aerial manatee surveys. 5. Overestimation of abundance by binomial mixture models owing to non-independent detections is problematic for ecological studies, but also for conservation. For example, in the case of endangered species, it could lead to inappropriate management decisions, such as downlisting. These issues will be increasingly relevant as more ecologists apply flexible N-mixture models to ecological data.

On the use of log-transformation vs. nonlinear regression for analyzing biological power laws.

PubMed

Xiao, Xiao; White, Ethan P; Hooten, Mevin B; Durham, Susan L

2011-10-01

Power-law relationships are among the most well-studied functional relationships in biology. Recently the common practice of fitting power laws using linear regression (LR) on log-transformed data has been criticized, calling into question the conclusions of hundreds of studies. It has been suggested that nonlinear regression (NLR) is preferable, but no rigorous comparison of these two methods has been conducted. Using Monte Carlo simulations, we demonstrate that the error distribution determines which method performs better, with NLR better characterizing data with additive, homoscedastic, normal error and LR better characterizing data with multiplicative, heteroscedastic, lognormal error. Analysis of 471 biological power laws shows that both forms of error occur in nature. While previous analyses based on log-transformation appear to be generally valid, future analyses should choose methods based on a combination of biological plausibility and analysis of the error distribution. We provide detailed guidelines and associated computer code for doing so, including a model averaging approach for cases where the error structure is uncertain.

Estimating magnitude and frequency of peak discharges for rural, unregulated, streams in West Virginia

USGS Publications Warehouse

Wiley, J.B.; Atkins, John T.; Tasker, Gary D.

2000-01-01

Multiple and simple least-squares regression models for the log10-transformed 100-year discharge with independent variables describing the basin characteristics (log10-transformed and untransformed) for 267 streamflow-gaging stations were evaluated, and the regression residuals were plotted as areal distributions that defined three regions of the State, designated East, North, and South. Exploratory data analysis procedures identified 31 gaging stations at which discharges are different than would be expected for West Virginia. Regional equations for the 2-, 5-, 10-, 25-, 50-, 100-, 200-, and 500-year peak discharges were determined by generalized least-squares regression using data from 236 gaging stations. Log10-transformed drainage area was the most significant independent variable for all regions.Equations developed in this study are applicable only to rural, unregulated, streams within the boundaries of West Virginia. The accuracy of estimating equations is quantified by measuring the average prediction error (from 27.7 to 44.7 percent) and equivalent years of record (from 1.6 to 20.0 years).

Financial Data Analysis by means of Coupled Continuous-Time Random Walk in Rachev-Rűschendorf Model

NASA Astrophysics Data System (ADS)

Jurlewicz, A.; Wyłomańska, A.; Żebrowski, P.

2008-09-01

We adapt the continuous-time random walk formalism to describe asset price evolution. We expand the idea proposed by Rachev and Rűschendorf who analyzed the binomial pricing model in the discrete time with randomization of the number of price changes. As a result, in the framework of the proposed model we obtain a mixture of the Gaussian and a generalized arcsine laws as the limiting distribution of log-returns. Moreover, we derive an European-call-option price that is an extension of the Black-Scholes formula. We apply the obtained theoretical results to model actual financial data and try to show that the continuous-time random walk offers alternative tools to deal with several complex issues of financial markets.

Improved method estimating bioconcentration/bioaccumulation factor from octanol/water partition coefficient

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meylan, W.M.; Howard, P.H.; Aronson, D.

1999-04-01

A compound`s bioconcentration factor (BDF) is the most commonly used indicator of its tendency to accumulate in aquatic organisms from the surrounding medium. Because it is expensive to measure, the BCF is generally estimated from the octanol/water partition coefficient (K{sub ow}), but currently used regression equations were developed from small data sets that do not adequately represent the wide range of chemical substances now subject to review. To develop and improved method, the authors collected BCF data in a file that contained information on measured BCFs and other key experimental details for 694 chemicals. Log BCF was then regressed againstmore » log K{sub ow} and chemicals with significant deviations from the line of best fit were analyzed by chemical structure. The resulting algorithm classifies a substance as either nonionic or ionic, the latter group including carboxylic acids, sulfonic acids and their salts, and quaternary N compounds. Log BCF for nonionics is estimated from log K{sub ow} and a series of correction factors if applicable; different equations apply for log K{sub ow} 1.0 to 7.0 and >7.0. For ionics, chemicals are categorized by log K{sub ow} and a log BCF in the range 0.5 to 1.75 is assigned. Organometallics, nonionics with long alkyl chains, and aromatic azo compounds receive special treatment. The correlation coefficient and mean error for log BCF indicate that the new method is a significantly better fit to existing data than other methods.« less

Enrollment Management in Medical School Admissions: A Novel Evidence-Based Approach at One Institution.

PubMed

Burkhardt, John C; DesJardins, Stephen L; Teener, Carol A; Gay, Steven E; Santen, Sally A

2016-11-01

In higher education, enrollment management has been developed to accurately predict the likelihood of enrollment of admitted students. This allows evidence to dictate numbers of interviews scheduled, offers of admission, and financial aid package distribution. The applicability of enrollment management techniques for use in medical education was tested through creation of a predictive enrollment model at the University of Michigan Medical School (U-M). U-M and American Medical College Application Service data (2006-2014) were combined to create a database including applicant demographics, academic application scores, institutional financial aid offer, and choice of school attended. Binomial logistic regression and multinomial logistic regression models were estimated in order to study factors related to enrollment at the local institution versus elsewhere and to groupings of competing peer institutions. A predictive analytic "dashboard" was created for practical use. Both models were significant at P < .001 and had similar predictive performance. In the binomial model female, underrepresented minority students, grade point average, Medical College Admission Test score, admissions committee desirability score, and most individual financial aid offers were significant (P < .05). The significant covariates were similar in the multinomial model (excluding female) and provided separate likelihoods of students enrolling at different institutional types. An enrollment-management-based approach would allow medical schools to better manage the number of students they admit and target recruitment efforts to improve their likelihood of success. It also performs a key institutional research function for understanding failed recruitment of highly desirable candidates.

Not in My Back Yard: A Comparative Analysis of Crime Around Publicly Funded Drug Treatment Centers, Liquor Stores, Convenience Stores, and Corner Stores in One Mid-Atlantic City.

PubMed

Furr-Holden, C Debra M; Milam, Adam J; Nesoff, Elizabeth D; Johnson, Renee M; Fakunle, David O; Jennings, Jacky M; Thorpe, Roland J

2016-01-01

This research examined whether publicly funded drug treatment centers (DTCs) were associated with violent crime in excess of the violence happening around other commercial businesses. Violent crime data and locations of community entities were geocoded and mapped. DTCs and other retail outlets were matched based on a Neighborhood Disadvantage score at the census tract level. Street network buffers ranging from 100 to 1,400 feet were placed around each location. Negative binomial regression models were used to estimate the relationship between the count of violent crimes and the distance from each business type. Compared with the mean count of violent crime around drug treatment centers, the mean count of violent crime (M = 2.87) was significantly higher around liquor stores (M = 3.98; t test; p < .01) and corner stores (M = 3.78; t test; p < .01), and there was no statistically significant difference between the count around convenience stores (M = 2.65; t test; p = .32). In the adjusted negative binomial regression models, there was a negative and significant relationship between the count of violent crime and the distance from drug treatment centers (β = -.069, p < .01), liquor stores (β = -.081, p < .01), corner stores (β = -.116, p < .01), and convenience stores (β = -.154, p < .01). Violent crime associated with drug treatment centers is similar to that associated with liquor stores and is less frequent than that associated with convenience stores and corner stores.

[Epidemiology of scrub typhus and influencing factors in Yunnan province, 2006-2013].

PubMed

Sun, Y; Shi, C; Li, X L; Fang, L Q; Cao, W C

2018-01-10

Objective: To understand the epidemiological characteristics of scrub typhu s and influencing factors in Yunnan province, and provide further information for the prevention and control of scrub typhus. Methods: Based on the incidence data of scrub typhus reported in Yunnan from 2006 to 2013, the epidemiological characteristics of scrub typhus were analyzed and related environmental factors were identified with panel negative binomial regression model. Results: A total of 8 980 scrub typhus cases were reported during 2006-2013 in Yunnan. The average annual incidence was 2.46/100 000, with an uptrend observed. Natural focus expansion was found, affecting 71.3% of the counties in 2013. The epidemic mainly occurred in summer and autumn with the incidence peak during July-October. The annual incidence was higher in females than in males. More cases occurred in children and farmers, the proportions of cases in farmers and pre-school aged children showed an obvious increase. Panel negative binomial regression model indicated that the transmission risk of scrub typhus was positive associated with monthly temperature and monthly relative humidity. Furthermore, an "U" pattern between the risk and the increased coverage of cropland and grassland as well as an "inverted-U" pattern between the risk and increased coverage of shrub were observed. Conclusion: It is necessary to strengthen the scrub typhus surveillance in warm and moist areas as well as the areas with high coverage of cropland and grassland in Yunnan, and the health education in children and farmers who are at high risk.

Use of clinical practice guidelines by dentists: findings from the Japanese dental practice-based research network.

PubMed

Kakudate, Naoki; Yokoyama, Yoko; Sumida, Futoshi; Matsumoto, Yuki; Gordan, Valeria V; Gilbert, Gregg H

2017-02-01

The objectives of this study were to: (1) examine differences in the use of dental clinical practice guidelines among Japanese dentists, and (2) identify characteristics associated with the number of guidelines used by participating dentists. We conducted a cross-sectional study consisting of a questionnaire survey in Japan between July 2014 and May 2015. The study queried dentists working in outpatient dental practices who are affiliated with the Dental Practice-Based Research Network Japan (n = 148). They were asked whether they have used each of 15 Japanese dental clinical guidelines. Associations between the number of guidelines used by participants and specific characteristics were analysed via negative binomial regression analysis. The mean number of guidelines used by participating dentists was 2.5 ± 2.9 [standard deviation (SD)]. Rate of use of guidelines showed substantial variation, from 5% to 34% among dentists. The proportion of dentists that used guidelines was the highest among oral medicine specialists, who had the highest proportion for 10 of 15 guidelines. Negative binomial regression analysis identified three factors significantly associated with the number of guidelines used: 'years since graduation from dental school', 'specialty practice' and 'practice busyness'. These results suggest that the use of clinical practice guidelines by Japanese dentists may still be inadequate. Training in the use of the guidelines could be given to dental students as undergraduate education and to young clinicians as continuing education. © 2016 John Wiley & Sons, Ltd.

Meta-analysis of studies with bivariate binary outcomes: a marginal beta-binomial model approach

PubMed Central

Chen, Yong; Hong, Chuan; Ning, Yang; Su, Xiao

2018-01-01

When conducting a meta-analysis of studies with bivariate binary outcomes, challenges arise when the within-study correlation and between-study heterogeneity should be taken into account. In this paper, we propose a marginal beta-binomial model for the meta-analysis of studies with binary outcomes. This model is based on the composite likelihood approach, and has several attractive features compared to the existing models such as bivariate generalized linear mixed model (Chu and Cole, 2006) and Sarmanov beta-binomial model (Chen et al., 2012). The advantages of the proposed marginal model include modeling the probabilities in the original scale, not requiring any transformation of probabilities or any link function, having closed-form expression of likelihood function, and no constraints on the correlation parameter. More importantly, since the marginal beta-binomial model is only based on the marginal distributions, it does not suffer from potential misspecification of the joint distribution of bivariate study-specific probabilities. Such misspecification is difficult to detect and can lead to biased inference using currents methods. We compare the performance of the marginal beta-binomial model with the bivariate generalized linear mixed model and the Sarmanov beta-binomial model by simulation studies. Interestingly, the results show that the marginal beta-binomial model performs better than the Sarmanov beta-binomial model, whether or not the true model is Sarmanov beta-binomial, and the marginal beta-binomial model is more robust than the bivariate generalized linear mixed model under model misspecifications. Two meta-analyses of diagnostic accuracy studies and a meta-analysis of case-control studies are conducted for illustration. PMID:26303591

Assessment of reportable disease incidence after Hurricane Sandy, New York City, 2012.

PubMed

Greene, Sharon K; Wilson, Elisha L; Konty, Kevin J; Fine, Annie D

2013-10-01

Hurricane Sandy's October 29, 2012 arrival in New York City caused flooding, power disruption, and population displacement. Infectious disease risk may have been affected by floodwater exposure, residence in emergency shelters, overcrowding, and lack of refrigeration or heating. For 42 reportable diseases that could have been affected by hurricane-related exposures, we developed methods to assess whether hurricane-affected areas had higher disease incidence than other areas of NYC. We identified post-hurricane cases as confirmed, probable, or suspected cases with onset or diagnosis between October 30 and November 26 that were reported via routine passive surveillance. Pre-hurricane cases for the same 4-week period were identified in 5 prior years, 2007-2011. Cases were geocoded to the census tract of residence. Using data compiled by the NYC Office of Emergency Management, we determined (1) the proportion of the population in each census tract living in a flooded block and (2) the subset of flooded tracts severely "impacted", e.g., by prolonged service outages or physical damage. A separate multivariable regression model was constructed for each disease, modeling the outcome of case counts using a negative binomial distribution. Independent variables were: neighborhood poverty; whether cases were pre- or post-hurricane (time); the proportion of the population flooded in impacted and not impacted tracts; and interaction terms between the flood/impact variables and time. Models used repeated measures to adjust for correlated observations from the same tract and an offset term of the log of the population size. Sensitivity analyses assessed the effects of case count fluctuations and accounted for variations in reporting volume by using an offset term of the log of total cases. Only legionellosis was statistically significantly associated with increased occurrence in flooded/impacted areas post-hurricane, adjusting for baseline differences (P = .04). However, there was only 1 legionellosis case post-hurricane in a flooded/impacted area. Hurricane Sandy did not appear to elevate reportable disease incidence in NYC. Defining and acquiring reliable data and meta-data regarding hurricane-affected areas was a challenge in the weeks post-storm. Relevant metrics could be developed during disaster preparedness planning. These methods to detect excess disease can be adapted for future emergencies.

Variable selection for zero-inflated and overdispersed data with application to health care demand in Germany

PubMed Central

Wang, Zhu; Shuangge, Ma; Wang, Ching-Yun

2017-01-01

In health services and outcome research, count outcomes are frequently encountered and often have a large proportion of zeros. The zero-inflated negative binomial (ZINB) regression model has important applications for this type of data. With many possible candidate risk factors, this paper proposes new variable selection methods for the ZINB model. We consider maximum likelihood function plus a penalty including the least absolute shrinkage and selection operator (LASSO), smoothly clipped absolute deviation (SCAD) and minimax concave penalty (MCP). An EM (expectation-maximization) algorithm is proposed for estimating the model parameters and conducting variable selection simultaneously. This algorithm consists of estimating penalized weighted negative binomial models and penalized logistic models via the coordinated descent algorithm. Furthermore, statistical properties including the standard error formulae are provided. A simulation study shows that the new algorithm not only has more accurate or at least comparable estimation, also is more robust than the traditional stepwise variable selection. The proposed methods are applied to analyze the health care demand in Germany using an open-source R package mpath. PMID:26059498

Atmospheric concentrations, sources and gas-particle partitioning of PAHs in Beijing after the 29th Olympic Games.

PubMed

Ma, Wan-Li; Sun, De-Zhi; Shen, Wei-Guo; Yang, Meng; Qi, Hong; Liu, Li-Yan; Shen, Ji-Min; Li, Yi-Fan

2011-07-01

A comprehensive sampling campaign was carried out to study atmospheric concentration of polycyclic aromatic hydrocarbons (PAHs) in Beijing and to evaluate the effectiveness of source control strategies in reducing PAHs pollution after the 29th Olympic Games. The sub-cooled liquid vapor pressure (logP(L)(o))-based model and octanol-air partition coefficient (K(oa))-based model were applied based on each seasonal dateset. Regression analysis among log K(P), logP(L)(o) and log K(oa) exhibited high significant correlations for four seasons. Source factors were identified by principle component analysis and contributions were further estimated by multiple linear regression. Pyrogenic sources and coke oven emission were identified as major sources for both the non-heating and heating seasons. As compared with literatures, the mean PAH concentrations before and after the 29th Olympic Games were reduced by more than 60%, indicating that the source control measures were effective for reducing PAHs pollution in Beijing. Copyright © 2011 Elsevier Ltd. All rights reserved.

Developing EHR-driven heart failure risk prediction models using CPXR(Log) with the probabilistic loss function.

PubMed

Taslimitehrani, Vahid; Dong, Guozhu; Pereira, Naveen L; Panahiazar, Maryam; Pathak, Jyotishman

2016-04-01

Computerized survival prediction in healthcare identifying the risk of disease mortality, helps healthcare providers to effectively manage their patients by providing appropriate treatment options. In this study, we propose to apply a classification algorithm, Contrast Pattern Aided Logistic Regression (CPXR(Log)) with the probabilistic loss function, to develop and validate prognostic risk models to predict 1, 2, and 5year survival in heart failure (HF) using data from electronic health records (EHRs) at Mayo Clinic. The CPXR(Log) constructs a pattern aided logistic regression model defined by several patterns and corresponding local logistic regression models. One of the models generated by CPXR(Log) achieved an AUC and accuracy of 0.94 and 0.91, respectively, and significantly outperformed prognostic models reported in prior studies. Data extracted from EHRs allowed incorporation of patient co-morbidities into our models which helped improve the performance of the CPXR(Log) models (15.9% AUC improvement), although did not improve the accuracy of the models built by other classifiers. We also propose a probabilistic loss function to determine the large error and small error instances. The new loss function used in the algorithm outperforms other functions used in the previous studies by 1% improvement in the AUC. This study revealed that using EHR data to build prediction models can be very challenging using existing classification methods due to the high dimensionality and complexity of EHR data. The risk models developed by CPXR(Log) also reveal that HF is a highly heterogeneous disease, i.e., different subgroups of HF patients require different types of considerations with their diagnosis and treatment. Our risk models provided two valuable insights for application of predictive modeling techniques in biomedicine: Logistic risk models often make systematic prediction errors, and it is prudent to use subgroup based prediction models such as those given by CPXR(Log) when investigating heterogeneous diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

Meta-analysis of studies with bivariate binary outcomes: a marginal beta-binomial model approach.

PubMed

Chen, Yong; Hong, Chuan; Ning, Yang; Su, Xiao

2016-01-15

When conducting a meta-analysis of studies with bivariate binary outcomes, challenges arise when the within-study correlation and between-study heterogeneity should be taken into account. In this paper, we propose a marginal beta-binomial model for the meta-analysis of studies with binary outcomes. This model is based on the composite likelihood approach and has several attractive features compared with the existing models such as bivariate generalized linear mixed model (Chu and Cole, 2006) and Sarmanov beta-binomial model (Chen et al., 2012). The advantages of the proposed marginal model include modeling the probabilities in the original scale, not requiring any transformation of probabilities or any link function, having closed-form expression of likelihood function, and no constraints on the correlation parameter. More importantly, because the marginal beta-binomial model is only based on the marginal distributions, it does not suffer from potential misspecification of the joint distribution of bivariate study-specific probabilities. Such misspecification is difficult to detect and can lead to biased inference using currents methods. We compare the performance of the marginal beta-binomial model with the bivariate generalized linear mixed model and the Sarmanov beta-binomial model by simulation studies. Interestingly, the results show that the marginal beta-binomial model performs better than the Sarmanov beta-binomial model, whether or not the true model is Sarmanov beta-binomial, and the marginal beta-binomial model is more robust than the bivariate generalized linear mixed model under model misspecifications. Two meta-analyses of diagnostic accuracy studies and a meta-analysis of case-control studies are conducted for illustration. Copyright © 2015 John Wiley & Sons, Ltd.

Somatic symptoms of anxiety and nonadherence to statin therapy.

PubMed

Korhonen, Maarit Jaana; Pentti, Jaana; Hartikainen, Juha; Kivimäki, Mika; Vahtera, Jussi

2016-07-01

The association between anxiety and nonadherence to preventive therapies remains unclear. We investigated whether somatic symptoms of anxiety predict statin nonadherence. This is a prospective cohort study of 1924 individuals who responded to a questionnaire survey on health status and initiated statin therapy after the survey during 2008-2010. We followed the cohort for nonadherence, defined as the proportion of days covered <80%, during the 365days since the first dispensation after the survey. We used log-binomial regression to estimate the predictors of nonadherence. 18% of participants reported no experience of the eight somatic symptoms of anxiety (palpitation without exercise, irregular heartbeat, chest pain upon anger or emotion, sweating without exercise, flushing, tremor of hands or voice, muscle twitching) before the statin initiation, and 16% had experienced at least one symptom on average weekly to daily. 49% of respondents were nonadherent. Weekly to daily occurrence of these symptoms predicted a 33% increase in the risk of nonadherence (risk ratio [RR] 1.33, 95% confidence interval, CI, 1.13-1.57) compared to no symptoms when adjusted for sociodemographics, lifestyle risks, cardiovascular comorbidities, and depression. Particularly, chest pain upon anger or emotion (RR 1.21, 95% CI 1.01-1.46) and muscle twitching (RR 1.24, 95% CI 1.08-1.42) predicted an increased risk of nonadherence to statin therapy. Psychological symptoms of anxiety were not associated with nonadherence when adjusted for somatic symptoms. Somatic anxiety-related symptoms predicted nonadherence to statin therapy. Information on pre-existing somatic symptoms may help identifying patients at increased risk of statin nonadherence. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Retention and HIV seroconversion among drug users on methadone maintenance treatment in Yunnan, China

PubMed Central

Duo, L.; Kumar, A. M. V.; Achanta, S.; Xue, H-M.; Satyanarayana, S.; Ananthakrishnan, R.; Srivastava, S.; Qi, W.; Hu, S-Y.

2014-01-01

Setting: Thirteen methadone maintenance treatment (MMT) clinics across Yunnan, the province with the highest human immunodeficiency virus (HIV) burden in China. Objectives: To determine, among HIV-negative participants on MMT, the proportion lost to follow-up (defined as those who missed the 6-monthly follow-up examination), factors associated with loss to follow-up (LFU), HIV seroconversion rate and factors associated with seroconversion. Design: Prospective cohort study from October 2008 to April 2011. All participants were administered a pre-tested structured questionnaire to capture associated factors and offered HIV testing every 6 months. χ2 test and log-binomial regression were used for data analysis. Results: Of 1146 participants, 541 (47%) were lost to follow-up in 2.5 years. Factors associated with higher LFU proportion include <6 months of previous MMT, inconvenient location of the MMT clinic and average methadone dose ⩽60 mg/day, with adjusted relative risks (RRs) of respectively 1.4 (95%CI 1.2–1.5), 1.2 (95%CI 1.0–1.4) and 1.1 (95%CI 1.0–1.3). The overall HIV seroconversion rate was 6.6 (95%CI 3.7–11.0) per 1000 person-years. Not living with a partner contributed to higher HIV rates, with an adjusted RR of 3.6 (95%CI 1.0–12.8). Conclusion: The retention rate of MMT participants in Yunnan was not satisfactory. Decentralising service delivery in the community and making directly observed treatment more convenient has the potential to improve retention. PMID:26423758

Risk of central nervous system defects in offspring of women with and without mental illness.

PubMed

Ayoub, Aimina; Fraser, William D; Low, Nancy; Arbour, Laura; Healy-Profitós, Jessica; Auger, Nathalie

2018-02-22

We sought to determine the relationship between maternal mental illness and the risk of having an infant with a central nervous system defect. We analyzed a cohort of 654,882 women aged less than 20 years between 1989 and 2013 who later delivered a live born infant in any hospital in Quebec, Canada. The primary exposure was mental illness during pregnancy or hospitalization for mental illness before pregnancy. The outcomes were neural and non-neural tube defects of the central nervous system in any offspring. We computed risk ratios (RR) and 95% confidence intervals (CI) for the association between mental disorders and risk of central nervous system defects in log-binomial regression models adjusted for age at delivery, total parity, comorbidity, socioeconomic deprivation, place of residence, and time period. Maternal mental illness was associated with an increased risk of nervous system defects in offspring (RR 1.76, 95% CI 1.64-1.89). Hospitalization for any mental disorder was more strongly associated with non-neural tube (RR 1.84, 95% CI 1.71-1.99) than neural tube defects (RR 1.31, 95% CI 1.08-1.59). Women at greater risk of nervous system defects in offspring tended to be diagnosed with multiple mental disorders, have more than one hospitalization for mental disease, or be 17 or older at first hospitalization. A history of mental illness is associated with central nervous system defects in offspring. Women hospitalized for mental illness may merit counseling at first symptoms to prevent central nervous system defects at pregnancy.

Which domains of childhood physical activity predict physical activity in adulthood? A 20-year prospective tracking study.

PubMed

Cleland, Verity; Dwyer, Terence; Venn, Alison

2012-06-01

It is important to examine how childhood physical activity is related to adult physical activity in order to best tailor physical activity-promotion strategies. The time- and resource-intensive nature of studies spanning childhood into adulthood means the understanding of physical activity trajectories over this time span is limited. This study aimed to determine whether childhood domain-specific physical activities predict domain-specific physical activity 20 years later in adulthood, and whether age and sex play a role in these trajectories. In 1985, 6412 children of age 9-15 years self-reported frequency and duration of discretionary sport and exercise (leisure activity), transport activity, school sport and physical education (PE) in the past week and number of sports played in the past year. In 2004-2006, 2201 of these participants (aged 26-36 years) completed the long International Physical Activity Questionnaire and/or wore a Yamax pedometer. Analyses included partial correlation coefficients and log-binomial regression. Childhood and adult activity were weakly correlated (r=-0.08-0.14). Total weekly physical activity in childhood did not predict adult activity. School PE predicted adult total weekly physical activity and daily steps (older females), while school sport demonstrated inconsistent associations. Leisure and transport activity in childhood predicted adult leisure activity among younger males and older females, respectively. Childhood past year sport participation positively predicted adult physical activity (younger males and older females). Despite modest associations between childhood and adult physical activity that varied by domain, age and sex, promoting a range of physical activities to children of all ages is warranted.

The role of intersection and street design on severity of bicycle-motor vehicle crashes

PubMed Central

Verma, Santosh; Mekary, Rania A; Courtney, Theodore K; Christiani, David C

2017-01-01

Background Safety concerns are a major barrier to cycling. Intersection and street design variables such as intersection angles and street width might contribute to the severity of crashes and the safety concerns. In this study we examined whether these design variables were associated with bicycle-motor vehicle crashes (BMVC) severity. Methods Using the geographical information system and latitudes/longitudes recorded by the police using a global positioning device, we extracted intersection angles, street width, bicycle facilities, posted speed limits and annual average daily traffic from 3266 BMVC data from New York City police records. Additional variables about BMVC, including age and sex of the bicyclist, time of the day, road surface conditions, road character, vehicle type and injury severity, were obtained from police reports. Injury severity was classified as severe (incapacitating or killed) or non-severe (non-incapacitating, possible injury). The associations between injury severity and environment design variables were examined using multivariate log-binomial regression model. Findings Compared with crashes at orthogonal intersections, crashes at non-orthogonal intersections had 1.37 times (95% CI 1.05 to 1.80) and non-intersection street segments had 1.31 times (95% CI 1.01 to 1.70) higher risk of a severe injury. Crashes that involved a truck or a bus were twice as likely to result in a severe injury outcome; street width was not significantly associated with injury severity. Conclusion Crashes at non-orthogonal intersections and non-intersection segments are more likely to result in higher injury severity. The findings can be used to improve road design and develop effective safety interventions. PMID:27881469

The role of birthplace and educational attainment on induced abortion inequalities.

PubMed

González-Rábago, Yolanda; Rodriguez-Alvarez, Elena; Borrell, Luisa N; Martín, Unai

2017-01-13

Induced abortion (IA) has shown social inequality related to birthplace and education with higher rates of IAs in immigrant and in less educated women relative to their native and highly educated counterparts. This study examined the independent and joint effects of birthplace and education on IA, repeated and IA performed during the 2nd trimester of pregnancy among women residing in the Basque Country, Spain. We conducted a cross-sectional population-based study of IA among women aged 25-49 years residing in the Basque Country, Spain, between 2011 and 2013. Log-binomial regression was used to quantify the independent and joint effects of birthplace and education attainment on all outcomes. Immigrant women exhibited higher probability of having an IAs (PR: 5.31), a repeated (PR: 7.23) or a 2nd trimester IAs (PR: 4.07) than women born in Spain. We observed higher probabilities for all outcomes among women with a primary or less education relative to those with a graduate education (All IAs PR: 2.51; repeated PR: 6.00; 2nd trimester PR: 3.08). However, no significant heterogeneity was observed for the effect of education on the association of birthplace with IAs, repeated or 2nd trimester IAs. Birthplace and education are key factors to explain not only an IA decision but also having a repeated or a 2nd trimester IA. However, the effects of birthplace and education may be independent from each other on these outcomes. A better understanding of these factors on IAs is needed when designing programs for sexual and reproductive health aimed to reduce inequalities among women.

Pre-gravid oral contraceptive use in relation to birth weight: a prospective cohort study

PubMed Central

Hatch, EE; Hahn, KA; Mikkelsen, EM; Riis, AH; Sorensen, HT; Rothman, KJ; Wise, LA

2015-01-01

Few studies have evaluated the association between pregravid oral contraceptive (OC) use and birth weight, and findings have been conflicting. We conducted a prospective cohort study of 5921 pregnancy planners in Denmark to evaluate recency, duration, and type of OC used before conception in relation to infant birth weight. Participants completed online questionnaires and reported detailed information on contraceptive history and covariates at baseline. Participants completed bimonthly follow-up questionnaires to update their pregnancy status for up to12 months or until conception occurred. Birth weight data were ascertained from the Danish Medical Birth Registry for 4046 live births delivered by study participants between 2008 and 2010. We used multivariable linear and log-binomial regression analyses to control for confounding. Mean birth weight was higher among women who had used OCs within 0–1 months (mean difference = 97 g, CI: 26, 168) or 2–6 months (mean difference=40 g, CI: −5, 85) before conception, compared with more than 12 months before conception. Mean birth weight was lower among women who had used OCs for long durations (mean difference comparing ≥12 with <4 years of OC use = −85 g, CI: −158, −11). Our findings indicate that pregravid OC use within 6 months of conception may be associated with a small increase in birth weight, but that long duration of use may have the opposite effect. Results were stronger among male infants, among 2nd and 4th generation OC users, and among users of OCs with a higher estrogen dose. PMID:26076921

Prevalence of Central Obesity among Adults with Normal BMI and Its Association with Metabolic Diseases in Northeast China.

PubMed

Zhang, Peng; Wang, Rui; Gao, Chunshi; Jiang, Lingling; Lv, Xin; Song, Yuanyuan; Li, Bo

2016-01-01

The present study aimed to investigate the prevalence of central obesity among adults with normal BMI and its association with metabolic diseases in Jilin Province, China. A population-based cross-sectional study was conducted in 2012 in Jilin Province of China. Information was collected by face to face interview. Descriptive data analysis and 95% confidence intervals (CI) of prevalence/frequency were conducted. Log-binomial regression analyses were used to find the independent factors associated with central obesity and to explore the adjusted association between central obesity and metabolic diseases among adults with normal BMI. Among the adult residents with normal BMI in Jilin Province, 55.6% of participants with central obesity self-assessed as normal weight and 27.0% thought their body weight were above normal. 12.7% of central obesity people took methods to lose weight, while 85.3% didn't. Female, older people and non-manual worker had higher risk to be central obesity among adults with normal BMI. Hypertension, diabetes and hyperlipidemia were significantly associated with central obesity among adults with normal BMI, the PRs were 1.337 (1.224-1.461), 1.323 (1.193-1.456) and 1.261 (1.152-1.381) separately when adjusted for gender, age and BMI. Hypertension, diabetes and hyperlipidemia were significantly associated with central obesity among adults with normal BMI in Jilin Province, China. The low rates of awareness and control of central obesity among adults with normal BMI should be improved by government and health department.

Relationships of organizational social capital with the presence of "gossip and slander," "quarrels and conflicts," sick leave, and poor work ability in nursing homes.

PubMed

Kiss, Philippe; De Meester, Marc; Kristensen, Tage S; Braeckman, Lutgart

2014-11-01

This study aimed to explore the associations of organizational social capital (OSC) with the presence of "gossip and slander," the presence of "conflicts and quarrels," sick leave prevalence, and prevalence of poor work ability in frontline working personnel of nursing homes. A total of 239 subjects (81 % participation), working in 11 different nursing homes, took part in a cross-sectional questionnaire study. Following end points were considered, they are as follows: prevalence of "gossip and slander," "conflicts and quarrels," sick leave, and poor work ability. Associations with OSC were explored at individual level (binomial log-linear regression analysis) and on group level (Kendall's tau correlation coefficients). Significant associations were found between OSC and "gossip and slander," sick leave, and poor work ability, both in the individual- and group-level analyses. The associations showed a higher significance level in the group-level analyses, with the strongest association found between mean OSC of the workplace and the prevalence of poor work ability at the workplace (τ = -0.722; p = 0.002). This study demonstrated significant associations of OSC with three end points that are relevant within the framework of well-being at work in nursing homes. The results are suggestive that OSC should be treated as a characteristic of the entire workplace, rather than as an individually experienced characteristic. The strikingly strong association between OSC and prevalence of poor work ability is suggestive for an important role of OSC within the context of maintaining work ability.

Patterns and Predictors of Fast Food Consumption After Acute Myocardial Infarction

PubMed Central

Salisbury, Adam C.; Chan, Paul S.; Gosch, Kensey L.; Buchanan, Donna M.; Spertus, John A.

2011-01-01

Although fast food is affordable and convenient, it is also high in calories, saturated fat and sodium. The frequency of fast food intake at the time of, and after, acute myocardial infarction (AMI) is modifiable. However, patterns of fast food intake and characteristics associated with its consumption among AMI patients are unknown. We studied fast food consumption at the time of AMI and 6 months later in 2481 patients from the prospective, 24-center TRIUMPH study of AMI patients. Fast food intake was categorized as frequent (≥ weekly) vs. infrequent (< weekly). Multivariable log-binomial regression was used to identify patient characteristics associated with frequent fast food intake 6 months after AMI. At baseline, 884 patients (36%) reported frequent fast food intake, which decreased to 503 (20%) 6 months after discharge (p-value <0.001). Male sex, white race, lack of college education, current employment and dyslipidemia were independently associated with frequent fast food intake 6 months after AMI. In contrast, older patients and those who had coronary bypass surgery were less likely to eat fast food frequently. Documentation of discharge dietary counseling was not associated with 6-month fast food intake. In conclusion, fast food consumption by AMI patients declined 6 months after the index hospitalization, but certain populations, including younger patients, men, those currently working, and less educated patients were more likely to consume fast food, at least weekly, during follow-up. Novel interventions that go beyond traditional dietary counseling may be needed to address continued fast food consumption after AMI in these patients. PMID:21306695

Influence of gestational weight gain on low birth weight in short-statured South Indian pregnant women.

PubMed

Shivakumar, Nirupama; Dwarkanath, Pratibha; Bosch, Ronald; Duggan, Christopher; Kurpad, Anura V; Thomas, Tinku

2018-05-01

India contributes to one-third of the global burden of low birth weight (LBW) neonates, which is associated with increased risk of mortality and adverse consequences on long-term health. Factors leading to LBW are multidimensional and maternal short stature is an important component with an inter-generational effect. On the contrary gestational weight gain (GWG) shows an independent positive influence on birth weight. The aim of the present study therefore was to determine the influence of GWG on birth weight in short pregnant women. A prospective observational cohort of 1254 pregnant women was studied. Total, second and third trimester GWG per week were computed. Women were divided into two groups, "short" and "not-short", using a cut off of 152 cm that corresponded to the 25th percentile for height in the cohort. Association of tertiles of GWG with LBW was examined using log binomial regression analysis. "Short" women in highest tertile of total GWG had a significantly reduced adjusted relative risk (ARR 0.37, 95% confidence interval 0.16-0.83, P = 0.016) for LBW, compared to the lowest tertile. However, there was no significant increase in risk for cesarean section (CS) with increasing tertiles of total GWG. In women with height <152 cm a significant reduced risk for LBW was observed with the greatest total GWG, without a significant increase in the risk for CS. This suggests that improving GWG in short women may be beneficial for the birth weight of the offspring.

Violence at the workplace increases the risk of musculoskeletal pain among nursing home workers

PubMed Central

Miranda, Helena; Punnett, Laura; Gore, Rebecca; Boyer, Jon

2018-01-01

Background Despite the high prevalences of workplace physical violence and musculoskeletal symptoms among health care workers, very few studies have examined the relationship between these two phenomena. Methods We surveyed 920 clinical nursing home workers by questionnaire regarding musculoskeletal pain in the low back, shoulders, wrists or hands, and knees. Information was also collected on exposure to physical assaults at work during the preceding 3 months, other workplace safety features, physical workload and psychosocial work environment. Log-binomial regression was used to estimate the prevalence ratios (PR) with 95% CIs. Results Almost one-half of respondents reported being assaulted at least once during the preceding 3 months by a resident or resident's visitor. The prevalence of low back pain increased from 40% among non-assaulted workers to 70% among those assaulted three or more times. The highest risk was found for widespread pain (three or more areas), with an adjusted PR of 2.7 (95% CI 1.8 to 3.9) for workers assaulted three or more times. Good workplace safety buffered the effects, so that violence increased the risk of most pains considerably less in a work environment perceived to be safe. Conclusions To our knowledge, this is the first study to show a dose–response association between physical assaults and musculoskeletal pain in a health care setting where violence is a frequent occurrence. This emphasises the need to address violence as a workplace hazard through practical measures for prevention as well as in future aetiological research on musculoskeletal disorders. PMID:20876554

Maternal Folate Intake during Pregnancy and Childhood Asthma in a Population-based Cohort.

PubMed

Parr, Christine L; Magnus, Maria C; Karlstad, Øystein; Haugen, Margaretha; Refsum, Helga; Ueland, Per M; McCann, Adrian; Nafstad, Per; Håberg, Siri E; Nystad, Wenche; London, Stephanie J

2017-01-15

A potential adverse effect of high folate intake during pregnancy on children's asthma development remains controversial. To prospectively investigate folate intake from both food and supplements during pregnancy and asthma at age 7 years when the diagnosis is more reliable than at preschool age. This study included eligible children born 2002-2006 from the Norwegian Mother and Child Cohort Study, a population-based pregnancy cohort, linked to the Norwegian Prescription Database. Current asthma at age 7 was defined by asthma medications dispensed at least twice in the year (1,901 cases; n = 39,846) or by maternal questionnaire report (1,624 cases; n = 28,872). Maternal folate intake was assessed with a food frequency questionnaire validated against plasma folate. We used log-binomial and multinomial regression to calculate adjusted relative risks with 95% confidence intervals. Risk of asthma was increased in the highest versus lowest quintile of total folate intake with an adjusted relative risk of 1.23 (95% confidence interval, 1.06-1.44) that was similar for maternally reported asthma. Mothers in the highest quintile had a relatively high intake of food folate (median, 308; interquartile range, 241-366 μg/d) and nearly all took at least 400 μg/d of supplemental folic acid (median, 500; interquartile range, 400-600 μg/d). In this large prospective population-based cohort with essentially complete follow-up, pregnant women taking supplemental folic acid at or above the recommended dose, combined with a diet rich in folate, reach a total folate intake level associated with a slightly increased risk of asthma in children.

Grandmother’s smoking when pregnant with the mother and asthma in the grandchild: the Norwegian Mother and Child Cohort Study

PubMed Central

Magnus, Maria C; Håberg, Siri E; Karlstad, Øystein; Nafstad, Per; London, Stephanie J; Nystad, Wenche

2016-01-01

Background A trans-generational influence of prenatal tobacco smoke exposure on asthma development has been proposed but the evidence remains sparse. Methods We examined the grandmother’s smoking when pregnant with the mother in relation to asthma outcomes in the grandchild [current asthma at 36 months (N=53,169,cases=3,013), current asthma at 7 years (N=25,394,cases=1,265) and dispensed asthma medications at 7 years in the Norwegian Prescription Database (N=45,607,cases=1,787)] within the Norwegian Mother and Child Cohort Study(MoBa). We calculated adjusted relative risks (adj. RR) and 95% confidence intervals (CI) using log binomial regression. Results A total of 23.5% of mothers reported that their mother smoked when pregnant with them. The grandmother’s smoking when pregnant with the mother was positively associated with asthma at 36 months [adj.RR 1.15 (95% CI: 1.06, 1.24)], asthma at 7 years [adj.RR 1.21 (95% CI: 1.07, 1.37)] and dispensed asthma medications at 7 years [adj.RR 1.15 (95% CI: 1.04, 1.26)]. This positive association did not differ significantly by the mother’s smoking status when pregnant with the child (P-values for multiplicative interaction >0.1). Conclusion The grandmother’s smoking when pregnant with the mother increased the risk of asthma in the grandchild independent of the mother’s smoking status. However, given limited information on the grandmother’s socio-economic status, asthma status and other factors, unmeasured confounding may be present. PMID:25572596

Intermediate vaginal flora is associated with HIV prevalence as strongly as bacterial vaginosis in a cross-sectional study of participants screened for a randomised controlled trial.

PubMed

Guédou, Fernand Aimé; Van Damme, Lut; Mirembe, Florence; Solomon, Suniti; Becker, Marissa; Deese, Jennifer; Crucitti, Tania; Alary, Michel

2012-11-01

The authors analysed data from female sex workers screened prior to participation in a microbicide trial to examine the association between prevalent vaginal flora abnormalities and HIV infection, with special emphasis on the role of the intermediate vaginal flora (IVF) in this association. Data from the Kampala, Cotonou, Chennai and Mudhol/Jamkhandi sites were analysed. Participants were interviewed and provided blood for HIV and syphilis antibody testing, genital samples for the diagnosis of vaginal flora abnormalities (using Nugent score) and other reproductive tract infections. Log-binomial regression was used to estimate the HIV prevalence ratio (PR) in relation to IVF and bacterial vaginosis (BV). Among 1367 women, BV, IVF and HIV prevalences were 47.6% (95% CI=45.0% to 50.3%), 19.2% (95% CI=17.1% to 21.2%) and 27.0% (95% CI=24.6% to 29.3%), respectively. In multivariate analysis, adjusting for study site, age, years of education, occupation, female sterilisation, oral sex, past history of sexually transmitted infection, gonorrhoea and candidiasis, IVF was significantly associated with HIV infection with a PR similar to that of BV (adjusted PR=1.56 (95% CI=1.22 to 1.98) and 1.48 (95% CI=1.20 to 1.84), respectively). Though the cross-sectional design of the study precludes directional interpretation of the findings, the data do suggest that IVF may be as important as BV in HIV acquisition. The authors recommend prospective research to better understand the association between IVF and HIV acquisition.

Preterm birth time trends in Europe: a study of 19 countries

PubMed Central

Zeitlin, J; Szamotulska, K; Drewniak, N; Mohangoo, AD; Chalmers, J; Sakkeus, L; Irgens, L; Gatt, M; Gissler, M; Blondel, B

2013-01-01

Objective To investigate time trends in preterm birth in Europe by multiplicity, gestational age, and onset of delivery. Design Analysis of aggregate data from routine sources. Setting Nineteen European countries. Population Live births in 1996, 2000, 2004, and 2008. Methods Annual risk ratios of preterm birth in each country were estimated with year as a continuous variable for all births and by subgroup using log-binomial regression models. Main outcome measures Overall preterm birth rate and rate by multiplicity, gestational age group, and spontaneous versus non-spontaneous (induced or prelabour caesarean section) onset of labour. Results Preterm birth rates rose in most countries, but the magnitude of these increases varied. Rises in the multiple birth rate as well as in the preterm birth rate for multiple births contributed to increases in the overall preterm birth rate. About half of countries experienced no change or decreases in the rates of singleton preterm birth. Where preterm birth rates rose, increases were no more prominent at 35–36 weeks of gestation than at 32–34 weeks of gestation. Variable trends were observed for spontaneous and non-spontaneous preterm births in the 13 countries with mode of onset data; increases were not solely attributed to non-spontaneous preterm births. Conclusions There was a wide variation in preterm birth trends in European countries. Many countries maintained or reduced rates of singleton preterm birth over the past 15 years, challenging a widespread belief that rising rates are the norm. Understanding these cross-country differences could inform strategies for the prevention of preterm birth. PMID:23700966

Does age modify the association between psychosocial factors at work and deterioration of self-rated health?

PubMed

Burr, Hermann; Hasselhorn, Hans Martin; Kersten, Norbert; Pohrt, Anne; Rugulies, Reiner

2017-09-01

Objectives Few epidemiological studies have examined whether associations of psychosocial working conditions with risk of poor health differ by age. Based on results from mostly cross-sectional studies, we test whether (i) psychosocial relational factors (social support) are more strongly associated with declining health of older than younger employees and (ii) psychosocial job factors (workpace, influence, possibilities for development) are more strongly associated with declining health of younger than older employees. Methods We extracted two cohorts from the Danish Work Environment Cohort Study (DWECS): the 2000-2005 and 2005-2010 cohorts. The participating 5281 employees with good self-rated health (SRH) at baseline were observed in 6585 5-year time windows. Using log-binomial regression analyses, we analysed whether psychosocial factors at work predicted 5-year deterioration of SRH. Effect modification by age was estimated by calculating relative excess risk due to interaction (RERI). Results High workpace among men, low influence at work as well as low social support from colleagues among women, and low possibilities for development and low social support from supervisors among both genders predicted 5-year decline in SRH. Of the 20 interaction analyses, only 1 was statistically significant and in the opposite direction of what was hypothesized (higher risk for declining SRH among middle-aged men with low possibilities for development compared to the young men with high possibilities for development). Conclusions Psychosocial working conditions predicted decline in SRH in this 5-year follow-up study. The model did not support our hypotheses about modifying effects by age.

Respiratory symptoms following wildfire smoke exposure: airway size as a susceptibility factor.

PubMed

Mirabelli, Maria C; Künzli, Nino; Avol, Edward; Gilliland, Frank D; Gauderman, W James; McConnell, Rob; Peters, John M

2009-05-01

Associations between exposure to smoke during wildfire events and respiratory symptoms are well documented, but the role of airway size remains unclear. We conducted this analysis to assess whether small airway size modifies these relationships. We analyzed data from 465 nonasthmatic 16- to 19-year-old participants in the Children's Health Study. Following an outbreak of wildfires in 2003, each student completed a questionnaire about smoke exposure, dry and wet cough, wheezing, and eye symptoms. We used log-binomial regression to evaluate associations between smoke exposure and fire-related health symptoms, and to assess modification of the associations by airway size. As a marker of airway size, we used the ratio of maximum midexpiratory flow to forced vital capacity. Forty percent (186 of 465) of this population (including students from 11 of 12 surveyed communities) reported the odor of wildfire smoke at home. We observed increased respiratory and eye symptoms with increasing frequency of wildfire smoke exposure. Associations between smoke exposure and having any of 4 respiratory symptoms were stronger in the lowest quartile of the lung function ratio (eg, fire smoke 6+ days: prevalence ratio: 3.8; 95% confidence interval (CI = 2.0-7.2), compared with the remaining quartiles (fire smoke 6+ days: prevalence ratio = 2.0; 1.2-3.2). Analysis of individual symptoms suggests that this interaction may be strongest for effects on wheezing. Small airways may serve as a marker of susceptibility to effects of wildfire smoke. Future studies should investigate the role of airway size for more common exposures and should include persons with asthma.

Respiratory Symptoms Following Wildfire Smoke Exposure

PubMed Central

Mirabelli, Maria C.; Künzli, Nino; Avol, Edward; Gilliland, Frank D.; Gauderman, W. James; McConnell, Rob; Peters, John M.

2015-01-01

Background Associations between exposure to smoke during wild-fire events and respiratory symptoms are well documented, but the role of airway size remains unclear. We conducted this analysis to assess whether small airway size modifies these relationships. Methods We analyzed data from 465 nonasthmatic 16- to 19-year-old participants in the Children’s Health Study. Following an outbreak of wildfires in 2003, each student completed a questionnaire about smoke exposure, dry and wet cough, wheezing, and eye symptoms. We used log-binomial regression to evaluate associations between smoke exposure and fire-related health symptoms, and to assess modification of the associations by airway size. As a marker of airway size, we used the ratio of maximum midexpiratory flow to forced vital capacity. Results Forty percent (186 of 465) of this population (including students from 11 of 12 surveyed communities) reported the odor of wildfire smoke at home. We observed increased respiratory and eye symptoms with increasing frequency of wildfire smoke exposure. Associations between smoke exposure and having any of 4 respiratory symptoms were stronger in the lowest quartile of the lung function ratio (eg, fire smoke 6+ days: prevalence ratio: 3.8; 95% confidence interval (CI = 2.0 –7.2), compared with the remaining quartiles (fire smoke 6+ days: prevalence ratio = 2.0; 1.2–3.2). Analysis of individual symptoms suggests that this interaction may be strongest for effects on wheezing. Conclusions Small airways may serve as a marker of susceptibility to effects of wildfire smoke. Future studies should investigate the role of airway size for more common exposures and should include persons with asthma. PMID:19276978

Reports of police beating and associated harms among people who inject drugs in Bangkok, Thailand: a serial cross-sectional study.

PubMed

Hayashi, Kanna; Ti, Lianping; Csete, Joanne; Kaplan, Karyn; Suwannawong, Paisan; Wood, Evan; Kerr, Thomas

2013-08-07

Thailand has for years attempted to address illicit drug use through aggressive drug law enforcement. Despite accounts of widespread violence by police against people who inject drugs (IDU), the impact of police violence has not been well investigated. In the wake of an intensified police crackdown in 2011, we sought to identify the prevalence and correlates of experiencing police beating among IDU in Bangkok. Community-recruited samples of IDU in Bangkok were surveyed between June 2009 and October 2011. Multivariate log-binomial regression was used to identify factors associated with reporting police beating. In total, 639 unique IDU participated in this serial cross-sectional study, with 240 (37.6%) participants reporting that they had been beaten by police. In multivariate analyses, reports of police beating were associated with male gender (Adjusted Prevalence Ratio [APR] = 4.43), younger age (APR = 1.69), reporting barriers to accessing healthcare (APR = 1.23), and a history of incarceration (APR = 2.51), compulsory drug detention (APR = 1.22) and syringe sharing (APR = 1.44), and study enrolment in 2011 (APR = 1.27) (all p < 0.05). Participants most commonly reported police beating during the interrogation process. A high proportion of IDU in Bangkok reported having been beaten by the police. Experiencing police beating was independently associated with various indicators of drug-related harm. These findings suggest that the over-reliance on enforcement-based approaches is contributing to police-perpetrated abuses and the perpetuation of the HIV risk behaviour among Thai IDU.

Associations of personal and family preeclampsia history with the risk of early-, intermediate- and late-onset preeclampsia.

PubMed

Boyd, Heather A; Tahir, Hassaan; Wohlfahrt, Jan; Melbye, Mads

2013-12-01

Preeclampsia encompasses multiple conditions of varying severity. We examined the recurrence and familial aggregation of preeclampsia by timing of onset, which is a marker for severity. We ascertained personal and family histories of preeclampsia for women who delivered live singletons in Denmark in 1978-2008 (almost 1.4 million pregnancies). Using log-linear binomial regression, we estimated risk ratios for the associations between personal and family histories of preeclampsia and the risk of early-onset (before 34 weeks of gestation, which is typically the most severe), intermediate-onset (at 34-36 weeks of gestation), and late-onset (after 36 weeks of gestation) preeclampsia. Previous early-, intermediate-, or late-onset preeclampsia increased the risk of recurrent preeclampsia with the same timing of onset 25.2 times (95% confidence interval (CI): 21.8, 29.1), 19.7 times (95% CI: 17.0, 22.8), and 10.3 times (95% CI: 9.85, 10.9), respectively, compared with having no such history. Preeclampsia in a woman's family was associated with a 24%-163% increase in preeclampsia risk, with the strongest associations for early- and intermediate-onset preeclampsia in female relatives. Preeclampsia in the man's family did not affect a woman's risk of early-onset preeclampsia and was only weakly associated with her risks of intermediate- and late-onset preeclampsia. Early-onset preeclampsia appears to have the largest genetic component, whereas environmental factors likely contribute most to late-onset preeclampsia. The role of paternal genes in the etiology of preeclampsia appears to be limited.

Early Posttherapy Hospitalizations Among Survivors of Childhood Leukemia and Lymphoma.

PubMed

Smitherman, Andrew B; Wilkins, Tania M; Blatt, Julie; Dusetzina, Stacie B

2016-08-01

Long-term survivors of childhood cancers are at increased risk for hospitalization. To test the hypothesis that many treatment-related morbidities are identifiable in the early posttherapy period, we determined the rates and causes for hospitalization among survivors of leukemia and lymphoma during the first 3 years posttherapy. Using a health plan claims database, we identified patients aged 0 to 21 years old treated for leukemia or lymphoma from 2000 to 2010. Survivors were matched 10:1 with similar children without a history of cancer. Hospitalization rates over 3 years were compared using Cox proportional hazards regression and risks of cause-specific hospitalization were compared using log-binomial models. Nineteen percent of childhood leukemia and lymphoma survivors were hospitalized in the first 3 years off therapy. Leukemia survivors (N=529) experienced over 6 times (hazard ratio=6.3; 95% confidence interval [CI], 4.9-8.0) and lymphoma survivors (N=454) over 3 times the hospitalization rate of controls (hazard ratio=3.2; 95% CI, 2.5-4.2). Compared with children without a cancer history, survivors were at increased risk for hospitalization due to infectious causes (leukemia: relative risk [RR], 60.0; 95% CI, 23.4-154.0; lymphoma: RR, 10.0; 95% CI, 4.4-22.9). In addition, lymphoma survivors were at increased risk for cardiovascular-related (RR, 15.0; 95% CI, 5.4-42.0) and pulmonary-related (RR, 8.1; 95% CI, 3.9-16.8) hospitalizations. These findings highlight the morbidity experienced by survivors and suggest that treatment-associated complications may be emerging soon after therapy completion.

Cross-sectional study on the weight and length of infants in the interior of the state of São Paulo, Brazil: associations with sociodemographic variables and breastfeeding.

PubMed

Bernardi, Julia Laura Delbue; Jordão, Regina Esteves; Barros Filho, Antônio de Azevedo

2009-07-01

Increasing obesity is starting to occur among Brazilians. The aim of this study was to investigate the weight and length of children under two years of age in relation to sociodemographic variables and according to whether they were breastfed. Cross-sectional randomized study conducted in 2004-2005, based on the declaration of live births (SINASC) in Campinas, Brazil. 2,857 mothers of newborns were interviewed and answered a questionnaire seeking socioeconomic and breastfeeding information. The newborns' weights and lengths were measured at the end of the interviews and the body mass index was calculated. Percentiles (< 15 and > 85) and Z-scores (< -1 and > +1) were used for classification based on the new growth charts recommended by WHO (2006). The log-rank test, multiple linear regression and binomial test (Z) were used. The statistical significance level used was 5%. The predominant social level was class C. The median for exclusive breastfeeding was 90 days; 61.25% of the children were between P15 and P85 for body mass index and 61.12% for length, respectively. Children whose mothers studied for nine to eleven years and children whose mothers were unemployed presented lower weight. Children whose mothers worked in health-related professions presented lower length when correlated with breastfeeding. The breastfeeding, maternal schooling and maternal occupation levels had an influence on nutrition status and indicated that obesity is occurring in early childhood among the infants living in the municipality.

Maternal uptake of pertussis cocooning strategy and other pregnancy related recommended immunizations.

PubMed

Wong, C Y; Thomas, N J; Clarke, M; Boros, C; Tuckerman, J; Marshall, H S

2015-01-01

Maternal immunization is an important strategy to prevent severe morbidity and mortality in mothers and their offspring. This study aimed to identify whether new parents were following immunization recommendations prior to pregnancy, during pregnancy, and postnatally. A cross-sectional survey was conducted by a questionnaire administered antenatally to pregnant women attending a maternity hospital with a follow-up telephone interview at 8-10 weeks post-delivery. Factors associated with uptake of pertussis vaccination within the previous 5 y or postnatally and influenza vaccination during pregnancy were explored using log binomial regression models. A total of 297 pregnant women completed the questionnaire. For influenza vaccine, 20.3% were immunized during pregnancy and 3.0% postnatally. For pertussis vaccine, 13.1% were vaccinated within 5 y prior to pregnancy and 31 women received the vaccine postnatally, 16 (51.6%) received the vaccine >4 weeks after delivery. Receiving a recommendation from a healthcare provider (HCP) was an independent predictor for receipt of both pertussis (RR 2.07, p < 0.001) and influenza vaccine (RR 2.26, p = 0.001). Non-English speaking mothers were significantly less likely to have received pertussis vaccination prior to pregnancy or postnatally (RR 0.24, p = 0.011). Multiparous pregnant women were less likely to have received an influenza vaccine during their current pregnancy (p = 0.015). Uptake of pregnancy related immunization is low and likely due to poor knowledge of availability, language barriers and lack of recommendations from HCPs. Strategies to improve maternal vaccine uptake should include education about recommended vaccines for both HCPs and parents and written information in a variety of languages.

Is pregnancy a teachable moment to promote handwashing with soap among primiparous women in rural Bangladesh? Follow-up of a randomised controlled trial.

PubMed

Kamm, Kelly B; Vujcic, Jelena; Nasreen, Sharifa; Luby, Stephen P; Zaman, K; El Arifeen, Shams; Ram, Pavani K

2016-12-01

Promoting handwashing with soap to mothers of young children can significantly reduce diarrhoea and pneumonia morbidity among children, but studies that measured long-term behaviour after interventions rarely found improvements in handwashing habits. Expecting mothers may experience emotional and social changes that create a unique environment that may encourage adoption of improved handwashing habits. The objective of this study was to determine whether exposure to an intensive handwashing intervention in the perinatal period (perinatal arm) was associated with improved maternal handwashing behaviour vs. exposure to the same intervention after the end of the perinatal period (post-neonatal arm). We identified primiparous women previously enrolled a randomised controlled handwashing intervention trial (November 2010-December 2011) and observed handwashing behaviours at the home 1-14 months after completion of the RCT (January-May 2012). We observed maternal handwashing and estimated the prevalence ratio (PR) of maternal handwashing using log-binomial regression. We enrolled 107 mothers in the perinatal arm and 105 mothers in the post-neonatal arm. Handwashing with soap at recommended times was low overall (4.6%) and comparable between arms (PR = 0.9, 95% CI 0.5, 1.5). This handwashing intervention was unable to develop and establish improved handwashing practices in primiparous women in rural Bangladesh. While pregnancy may present an opportunity and motivation to do so, further studies should assess whether social, individual and environmental influences overcome this motivation and prevent handwashing with soap among new mothers. © 2016 John Wiley & Sons Ltd.

Correlates of anaemia in pregnant urban South Indian women: a possible role of dietary intake of nutrients that inhibit iron absorption.

PubMed

Samuel, Tinu Mary; Thomas, Tinku; Finkelstein, Julia; Bosch, Ronald; Rajendran, Ramya; Virtanen, Suvi M; Srinivasan, Krishnamachari; Kurpad, Anura V; Duggan, Christopher

2013-02-01

To identify correlates of anaemia during the first trimester of pregnancy among 366 urban South Indian pregnant women. Cross-sectional study evaluating demographic, socio-economic, anthropometric and dietary intake data on haematological outcomes. A government maternity health-care centre catering predominantly to the needs of pregnant women from the lower socio-economic strata of urban Bangalore. Pregnant women (n 366) aged ≥18 and ≤40 years, who registered for antenatal screening at ≤14 weeks of gestation. Mean age was 22·6 (sd 3·4) years, mean BMI was 20·4 (sd 3·3) kg/m2 and 236 (64·5 %) of the pregnant women were primiparous. The prevalence of anaemia (Hb <11·0 g/dl) was 30·3 % and of microcytic anaemia (anaemia with mean corpuscular volume <80 fl) 20·2 %. Mean dietary intakes of energy, Ca, Fe and folate were well below the Indian RDA. In multivariable log-binomial regression analysis, anaemia was independently associated with high dietary intakes of Ca (relative risk; 95 % CI: 1·79; 1·16, 2·76) and P (1·96; 1·31, 2·96) and high intake of meat, fish and poultry (1·94; 1·29, 2·91). Low dietary intake of multiple micronutrients, but higher intakes of nutrients that inhibit Fe absorption such as Ca and P, may help explain high rates of maternal anaemia in India.

Maternal History of Child Abuse and Obesity Risk in Offspring: Mediation by Weight in Pregnancy.

PubMed

Leonard, Stephanie A; Petito, Lucia C; Rehkopf, David H; Ritchie, Lorrene D; Abrams, Barbara

2017-08-01

Women's experience of childhood adversity may contribute to their children's risk of obesity. Possible causal pathways include higher maternal weight and gestational weight gain, which have been associated with both maternal childhood adversity and obesity in offspring. This study included 6718 mother-child pairs from the National Longitudinal Survey of Youth 1979 in the United States (1979-2012). We applied multiple log-binomial regression models to estimate associations between three markers of childhood adversity (physical abuse, household alcoholism, and household mental illness) and offspring obesity in childhood. We estimated natural direct effects to evaluate mediation by prepregnancy BMI and gestational weight gain. Among every 100 mothers who reported physical abuse in childhood, there were 3.7 (95% confidence interval: -0.1 to 7.5) excess cases of obesity in 2- to 5-year olds compared with mothers who did not report physical abuse. Differences in prepregnancy BMI, but not gestational weight gain, accounted for 25.7% of these excess cases. There was no evidence of a similar relationship for household alcoholism or mental illness or for obesity in older children. In this national, prospective cohort study, prepregnancy BMI partially explained an association between maternal physical abuse in childhood and obesity in preschool-age children. These findings underscore the importance of life-course exposures in the etiology of child obesity and the potential multi-generational consequences of child abuse. Research is needed to determine whether screening for childhood abuse and treatment of its sequelae could strengthen efforts to prevent obesity in mothers and their children.

Gender-specific associations between leisure-time physical activity and symptoms of anxiety: the HUNT study.

PubMed

Brunes, Audun; Gudmundsdottir, Sigridur Lara; Augestad, Liv Berit

2015-03-01

The underlying goal of the study was to examine gender-specific effects of leisure-time physical activity on the development of symptoms of anxiety. The second wave of a prospective cohort survey (HUNT 2) was conducted during 1995-1997 in the county of Nord-Trøndelag, Norway, with a follow-up in 2006-2008 (HUNT 3). The sample consisted of 12,796 women and 11,195 men with an age range of 19-85 years. A binomial model with a log-link function and generalized linear model analysis with gamma distribution was used to assess the association between physical activity and anxiety symptoms (Hospital Anxiety and Depression Scale anxiety subscale, HADS-A). A total of 1,211 (9.5 %) women and 650 (5.8 %) men developed HADS-defined anxiety (≥8 on the HADS-A scale). Men who scored in the middle tertile of the calculated physical activity index developed significantly fewer cases of HADS-defined anxiety compared with men in the lowest tertile (p < 0.05). In the gamma regression analysis for women, having higher scores on the moderate-high physical activity was associated with fewer symptoms of anxiety (p < 0.01). Women developed almost twice as many cases of HADS-defined anxiety compared to men. Significant associations were found between general leisure-time physical activity and anxiety symptoms among women and men, but the true effect is likely to be different from the observed associations due to several threats to the internal validity in the study.

Socio-economic differences in takeaway food consumption among adults.

PubMed

Miura, Kyoko; Giskes, Katrina; Turrell, Gavin

2012-02-01

To examine socio-economic differences in the frequency and types of takeaway foods consumed. A cross-sectional postal survey. Participants were asked about their usual consumption of overall takeaway food (<4 times/month or ≥4 times/month) and of twenty-two specific takeaway food items (<1 time/month or ≥1 time/month); these latter foods were grouped into 'healthy' and 'less healthy' choices. Socio-economic position was measured on the basis of educational level and equivalised household income, and differences in takeaway food consumption were assessed by calculating prevalence ratios using log binomial regression. Adults aged 25-64 years from Brisbane, Australia, were randomly selected from the electoral roll (n 903; 63·7 % response rate). Compared with their more educated counterparts, the least educated were more regular consumers of overall takeaway food and fruit or vegetable juice and less regular consumers of sushi. For the 'less healthy' items, the least educated more regularly consumed potato chips, savoury pies, fried chicken and non-diet soft drinks; however, the least educated were less likely to consume curry. Household income was not associated with overall takeaway consumption. The lowest-income group was a more regular consumer of fruit or vegetable juice compared with the highest-income group. Among the 'less healthy' items, the lowest-income group was a more regular consumer of fried fish, ice cream and milk shakes, whereas curry was consumed less regularly. The frequency and types of takeaway foods consumed by socio-economically disadvantaged groups may contribute to inequalities in overweight or obesity and to chronic disease.

Acquired Color Vision Defects and Hexane Exposure: A Study of San Francisco Bay Area Automotive Mechanics.

PubMed

Beckman, Stella; Eisen, Ellen A; Bates, Michael N; Liu, Sa; Haegerstrom-Portnoy, Gunilla; Hammond, S Katharine

2016-06-01

Occupational exposure to solvents, including n-hexane, has been associated with acquired color vision defects. Blue-yellow defects are most common and may be due to neurotoxicity or retinal damage. Acetone may potentiate the neurotoxicity of n-hexane. We present results on nonhexane solvent and hexane exposure and color vision from a cross-sectional study of 835 automotive repair workers in the San Francisco Bay Area, California (2007-2013). Cumulative exposure was estimated from self-reported work history, and color vision was assessed using the Lanthony desaturated D-15 panel test. Log-binomial regression was used to estimate prevalence ratios for color vision defects. Acquired color vision defects were present in 29% of participants, of which 70% were blue-yellow. Elevated prevalence ratios were found for nonhexane solvent exposure, with a maximum of 1.31 (95% confidence interval (CI): 0.86, 2.00) for blue-yellow. Among participants aged ≤50 years, the prevalence ratio for blue-yellow defects was 2.17 (95% CI: 1.03, 4.56) in the highest quartile of nonhexane solvent exposure and 1.62 (95% CI: 0.97, 2.72) in the highest category of exposure to hexane with acetone coexposure. Cumulative exposures to hexane and nonhexane solvents in the highest exposure categories were associated with elevated prevalence ratios for color vision defects in younger participants. © The Author 2016. 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.

[Socioeconomic inequalities in subjective health among 11- to 15-year-olds in Germany. A trend analysis from 2002-2010].

PubMed

Moor, I; Pförtner, T K; Lampert, T; Ravens-Sieberer, U; Richter, M

2012-07-01

Health is strongly linked to social position. Several studies showed consistent or increasing health inequalities in the last decades. So far, few studies focused on trends in social inequalities in health among children and adolescents. The objective of this study was to determine changes in socioeconomic differences in subjective health between 2002 and 2010 of 11- to 15-year-old students in Germany.Data were obtained from the German part of the cross-sectional WHO "Health Behaviour in School-aged Children" survey in 2002 (n=5.221), 2006 (n=6.896) and 2010 (n=4.723). Log binomial regression models were used to assess the extent of inequalities in self-rated health across the survey years. Socioeconomic position was measured using the family affluence scale (FAS) and perceived family wealth.A relatively small improvement in good/excellent self-rated health was observed in both boys and girls from 2002 (85.2%) to 2010 (87%). Despite this improvement, inequalities in self-rated health could be identified for all survey years, regardless of which socioeconomic indicator was used (RR 1.4 up to 1.8). The level of these differences remained virtually unchanged in girls and boys in that time period.The same relationship of family affluence, family wealth and self-rated health has persisted for almost a decade in Germany. Recent strategies could not tackle existing inequalities in self-rated health which indicates an increasing need to develop and implement innovative measures and to intensify efforts of social and health policy. © Georg Thieme Verlag KG Stuttgart · New York.

The impact of pregnancy on physical activity level.

PubMed

Fell, Deshayne B; Joseph, K S; Armson, B Anthony; Dodds, Linda

2009-09-01

The purpose of this study was to compare women's levels of physical activity during early pregnancy and during the year before pregnancy, and to identify characteristics associated with discontinuing sports and exercise among women previously active during the year before pregnancy. Data collected from 1,737 women enrolled in a prospective cohort study and who had no contraindications for exercise were included in this analysis. Measures of physical activity (including household and care-giving activities, active living and sports and exercise activities) during early pregnancy were compared to the year before pregnancy. Log binomial regression was used to identify factors associated with discontinuing sports and exercise during pregnancy. There was a statistically significant decrease in all summary measures of physical activity during early pregnancy. The largest decreases were observed in sports and exercise activity. Among women active before pregnancy, age <35 years, multiparity, less than university education, pre-pregnancy body mass index (BMI) > or = 30 kg/m(2) and lower levels of pre-pregnancy exercise were associated with discontinuing sports and exercise activities during pregnancy. Most women reduced their physical activity level during the first 20 weeks of pregnancy compared with their level of activity during the year prior to pregnancy, particularly for sports and exercise, although a small proportion of women in this study actually increased their activity in this area during early pregnancy. Participation in sports and exercise activity during pregnancy is potentially modifiable and could favorably impact perinatal health and maternal post-partum weight. The results of this study suggests that pregnancy is an event that leads to a decrease in physical activity.

Family caregivers' reported nonadherence to the controller medication of asthma in children in Casablanca (Morocco): Extent and associated factors.

PubMed

Ménard, Sandra; Jbilou, Jalila; Lauzier, Sophie

2018-01-16

Recent statistics show a relatively high prevalence of asthma among Moroccan children and a weak control over their symptoms. To our knowledge, no research has been carried out to document adherence to the controller treatment in this population. This study aims 1) to assess the extent of children's nonadherence to the controller treatment of asthma in an urban region of Morocco as reported by a family caregiver, and 2) to identify the associated factors. We conducted a cross-sectional study among caregivers of asthmatic children (2-12 years old) in different health and education facilities of Casablanca-Settat. We administered face-to-face questionnaires incorporating validated instruments (Medication Adherence Rating Scale-Asthma (MARS-A), Beliefs about Medicines Questionnaire (BMQ), Asthma Knowledge Questionnaire). Univariate and multivariate log-binomial regressions evaluating the association between several factors and reported nonadherence were performed (prevalence ratios (PR) and 95% confidence intervals (CI)). Through two public hospitals, three private medical clinics, and one private school, 103 caregivers were recruited. Low adherence to the controller treatment of asthma was reported by 48% of the caregivers (MARS-A <45). In the multivariate model, caregivers with the lowest level of knowledge about asthma were almost three times more likely to report low adherence compared to caregivers with the highest level (PR = 2.93; 95% CI: 1.14-7.52). This study highlights the finding that low adherence is widespread in this context and also the importance of targeting caregivers' knowledge of asthma for interventions.

Relationship between Nutritional Support and Tuberculosis Treatment Outcomes in West Bengal, India.

PubMed

Samuel, Blesson; Volkmann, Tyson; Cornelius, Sushma; Mukhopadhay, Sugata; MejoJose; Mitra, Kaushik; Kumar, Ajay M V; Oeltmann, John E; Parija, Sidhajyoti; Prabhakaran, Aslesh Ottapura; Moonan, Patrick K; Chadha, Vineet K

2016-12-01

Poverty and poor nutrition are associated with the risk of developing tuberculosis (TB). Socioeconomic factors may interfere with anti-tuberculosis treatment compliance and its outcome. We examined whether providing nutritional support (monthly supply of rice and lentil beans) to TB patients who live below the poverty line was associated with TB treatment outcome. This was a retrospective cohort study of sputum smear-positive pulmonary TB patients living below the poverty line (income of <$1.25 per day) registered for anti-tuberculosis treatment in two rural districts of West Bengal, India during 2012 to 2013. We compared treatment outcomes among patients who received nutritional support with those who did not. A log-binomial regression model was used to assess the relation between nutritional support and unsuccessful treatment outcome (loss-to-follow-up, treatment failure and death). Of 173 TB patients provided nutritional support, 15 (9%) had unsuccessful treatment outcomes, while 84 (21%) of the 400 not provided nutrition support had unsuccessful treatment outcomes (p < 0.001). After adjusting for age, sex and previous treatment, those who received nutritional support had a 50% reduced risk of unsuccessful treatment outcome than those who did not receive nutritional support (Relative Risk: 0.51; 95% Confidence Intervals: 0.30 - 0.86). Under programmatic conditions, monthly rations of rice and lentils were associated with lower risk of unsuccessful treatment outcome among impoverished TB patients. Given the relatively small financial commitment needed per patient ($10 per patient per month), the national TB programme should consider scaling up nutritional support among TB patients living below the poverty line.

Relationship between Nutritional Support and Tuberculosis Treatment Outcomes in West Bengal, India

PubMed Central

Samuel, Blesson; Volkmann, Tyson; Cornelius, Sushma; Mukhopadhay, Sugata; MejoJose; Mitra, Kaushik; Kumar, Ajay M. V.; Oeltmann, John E.; Parija, Sidhajyoti; Prabhakaran, Aslesh Ottapura; Moonan, Patrick K.; Chadha, Vineet K.

2016-01-01

Introduction Poverty and poor nutrition are associated with the risk of developing tuberculosis (TB). Socioeconomic factors may interfere with anti-tuberculosis treatment compliance and its outcome. We examined whether providing nutritional support (monthly supply of rice and lentil beans) to TB patients who live below the poverty line was associated with TB treatment outcome. Methods This was a retrospective cohort study of sputum smear-positive pulmonary TB patients living below the poverty line (income of <$1.25 per day) registered for anti-tuberculosis treatment in two rural districts of West Bengal, India during 2012 to 2013. We compared treatment outcomes among patients who received nutritional support with those who did not. A log-binomial regression model was used to assess the relation between nutritional support and unsuccessful treatment outcome (loss-to-follow-up, treatment failure and death). Results Of 173 TB patients provided nutritional support, 15 (9%) had unsuccessful treatment outcomes, while 84 (21%) of the 400 not provided nutrition support had unsuccessful treatment outcomes (p < 0.001). After adjusting for age, sex and previous treatment, those who received nutritional support had a 50% reduced risk of unsuccessful treatment outcome than those who did not receive nutritional support (Relative Risk: 0.51; 95% Confidence Intervals: 0.30 - 0.86). Conclusion Under programmatic conditions, monthly rations of rice and lentils were associated with lower risk of unsuccessful treatment outcome among impoverished TB patients. Given the relatively small financial commitment needed per patient ($10 per patient per month), the national TB programme should consider scaling up nutritional support among TB patients living below the poverty line. PMID:28042591

Beyond access: barriers to internet health information seeking among the urban poor

PubMed Central

Okechukwu, Cassandra A; Sorensen, Glorian; Viswanath, K

2016-01-01

Objective Communication inequalities deepen health disparities even when internet access is achieved. The goal of this study is to understand how a range of barriers may inhibit individuals from low socioeconomic position (SEP) from engaging with online health information even when it is freely available. Materials and methods Detailed data were collected from 118 low-SEP individuals from a randomized controlled trial providing internet access. Measures triangulated the health-seeking experience through internet use tracked in real-time, call log data, and self-reported barriers. Negative binomial regression models were fitted with technology and perceived predictors, and our outcome, health information seeking, and then stratified by medical status. Results Participants experienced a median of two computer issues (median 6 days) and two internet issues (median 6.5 days). Duration of internet problems was associated with a decrease in the rate of internet health information seeking by a factor of 0.990 (P = .03) for each additional day. Participants with a medical problem who were frustrated in their search for health information had half the rate of health information seeking of those who were not frustrated (incidence rate ratio = 0.395, P = .030). Discussion Despite IT support, participants still experienced internet connectivity issues that negatively impacted their health information seeking. Frustration in their search to find information may serve as an additional barrier to those who have medical issues. Conclusion After initial internet access, a second-level digital divide emerged due to connectivity issues, highlighting the need to understand the complex network of barriers experienced by low-SEP internet users. PMID:27206459

Hydroxyurea Use in Young Children With Sickle Cell Anemia in New York State.

PubMed

Anders, David G; Tang, Fei; Ledneva, Tatania; Caggana, Michele; Green, Nancy S; Wang, Ying; Sturman, Lawrence S

2016-07-01

This study examined hydroxyurea usage in young children with sickle cell anemia within New York State (NYS). The cohort was 273 children with sickle cell anemia born in NYS in 2006-2009 and enrolled essentially continuously in Medicaid for the first 4 years of life. Medicaid data were used to examine hydroxyurea usage in this group by age at first prescription fill, persistence, region, treatment institution, and year. Log-binomial regression models were used to estimate the likelihood of receiving hydroxyurea treatment. Data from birth through 2014 for all members of the study group were assembled and analyzed in 2015. About 25% of the cohort had at least one filled hydroxyurea prescription by their fifth birthday, and nearly 40% by the end of the study period. The mean proportion of days covered for the first year of therapy was 56.3%. Adherence was also assessed by calculating medication possession ratios for individual treatment periods. Slightly more than one third of treated children showed 80% coverage by these measures. There was a consistent, but not statistically significant, trend toward younger age at first fill. Significant regional and treatment center differences in initiation of hydroxyurea use, but not in persistence after initiation, were noted among NYS centers. Subsequent to clinical studies demonstrating safety, current NYS-wide use of hydroxyurea in young children with sickle cell anemia appears to be widespread and increasing. However, practice differences between treatment centers and inadequate adherence may limit the full disease-modifying effects of hydroxyurea. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

A Health Profile of Arab Americans in Michigan: A Novel Approach to Using a Hospital Administrative Database.

PubMed

Dallo, Florence J; Ruterbusch, Julie J; Kirma, Joseph David; Schwartz, Kendra; Fakhouri, Monty

2016-12-01

The objectives of this study were to estimate and compare the prevalence of heart disease, cancer, chronic lower respiratory disease, stroke, Alzheimer's, diabetes, nephrosis, flu/pneumonia, hypertension, and atherosclerosis between Arab Americans and whites attending a large, metropolitan hospital system. The sample included 68,047 patients, 18 years of age or older, who visited the hospital during 2012. Demographic and disease variables were electronically abstracted. Demographic characteristics were compared between Arab Americans and whites using Chi square tests. Sex specific, age-adjusted prevalence ratios (PR) and 95 % confidence intervals were estimated for these two groups using a log-binomial regression model. Compared to white men, Arab American men had a higher prevalence of diabetes (PR 1.40, 95 % CI 1.29-1.52) and hypertension (PR 1.07, 95 % CI 1.04-1.10), and a lower prevalence of chronic lower respiratory disease (PR 0.74, 95 % CI 0.66-0.83). Compared to white women, Arab American women had a higher prevalence of chronic lower respiratory disease (PR 1.12, 95 % CI 1.01-1.25), diabetes (PR 1.49, 95 % CI 1.38-1.60), influenza/pneumonia (PR 1.26, 95 % CI 1.05-1.51) and hypertension (PR 1.04, 95 % CI 1.01-1.08). This study supports previous findings that health disparities exist for Arab Americans, who are classified as "white" in health statistics. Standard inclusion of Arab American as a separate ethnicity category will aid researchers in assessing the health care needs of this growing minority community.

Comparison of boiling and chlorination on the quality of stored drinking water and childhood diarrhoea in Indonesian households

PubMed Central

FAGERLI, K.; TRIVEDI, K. K.; SODHA, S. V.; BLANTON, E.; ATI, A.; NGUYEN, T.; DELEA, K. C.; AINSLIE, R.; FIGUEROA, M. E.; KIM, S.; QUICK, R.

2018-01-01

SUMMARY We compared the impact of a commercial chlorination product (brand name Air RahMat) in stored drinking water to traditional boiling practices in Indonesia. We conducted a baseline survey of all households with children <5 years in four communities, made 11 subsequent weekly home visits to assess acceptability and use of water treatment methods, measured Escherichia coli concentration in stored water, and determined diarrhoea prevalence among children <5 years. Of 281 households surveyed, boiling (83%) and Air RahMat (7%) were the principal water treatment methods. Multivariable log-binomial regression analyses showed lower risk of E. coli in stored water treated with Air RahMat than boiling (risk ratio (RR) 0·75, 95% confidence interval (CI) 0·56–1·00). The risk of diarrhoea in children <5 years was lower among households using Air RahMat (RR 0·43, 95% CI 0·19–0·97) than boiling, and higher in households with E. coli concentrations of 1–1000 MPN/100 ml (RR 1·54, 95% CI 1·04–2·28) or >1000 MPN/100 ml (RR 1·86, 95% CI 1·09–3·19) in stored water than in households without detectable E. coli. Although results suggested that Air RahMat water treatment was associated with lower E. coli contamination and diarrhoeal rates among children <5 years than water treatment by boiling, Air RahMat use remained low. PMID:28942755

A comparison of methods to handle skew distributed cost variables in the analysis of the resource consumption in schizophrenia treatment.

PubMed

Kilian, Reinhold; Matschinger, Herbert; Löeffler, Walter; Roick, Christiane; Angermeyer, Matthias C

2002-03-01

Transformation of the dependent cost variable is often used to solve the problems of heteroscedasticity and skewness in linear ordinary least square regression of health service cost data. However, transformation may cause difficulties in the interpretation of regression coefficients and the retransformation of predicted values. The study compares the advantages and disadvantages of different methods to estimate regression based cost functions using data on the annual costs of schizophrenia treatment. Annual costs of psychiatric service use and clinical and socio-demographic characteristics of the patients were assessed for a sample of 254 patients with a diagnosis of schizophrenia (ICD-10 F 20.0) living in Leipzig. The clinical characteristics of the participants were assessed by means of the BPRS 4.0, the GAF, and the CAN for service needs. Quality of life was measured by WHOQOL-BREF. A linear OLS regression model with non-parametric standard errors, a log-transformed OLS model and a generalized linear model with a log-link and a gamma distribution were used to estimate service costs. For the estimation of robust non-parametric standard errors, the variance estimator by White and a bootstrap estimator based on 2000 replications were employed. Models were evaluated by the comparison of the R2 and the root mean squared error (RMSE). RMSE of the log-transformed OLS model was computed with three different methods of bias-correction. The 95% confidence intervals for the differences between the RMSE were computed by means of bootstrapping. A split-sample-cross-validation procedure was used to forecast the costs for the one half of the sample on the basis of a regression equation computed for the other half of the sample. All three methods showed significant positive influences of psychiatric symptoms and met psychiatric service needs on service costs. Only the log- transformed OLS model showed a significant negative impact of age, and only the GLM shows a significant negative influences of employment status and partnership on costs. All three models provided a R2 of about.31. The Residuals of the linear OLS model revealed significant deviances from normality and homoscedasticity. The residuals of the log-transformed model are normally distributed but still heteroscedastic. The linear OLS model provided the lowest prediction error and the best forecast of the dependent cost variable. The log-transformed model provided the lowest RMSE if the heteroscedastic bias correction was used. The RMSE of the GLM with a log link and a gamma distribution was higher than those of the linear OLS model and the log-transformed OLS model. The difference between the RMSE of the linear OLS model and that of the log-transformed OLS model without bias correction was significant at the 95% level. As result of the cross-validation procedure, the linear OLS model provided the lowest RMSE followed by the log-transformed OLS model with a heteroscedastic bias correction. The GLM showed the weakest model fit again. None of the differences between the RMSE resulting form the cross- validation procedure were found to be significant. The comparison of the fit indices of the different regression models revealed that the linear OLS model provided a better fit than the log-transformed model and the GLM, but the differences between the models RMSE were not significant. Due to the small number of cases in the study the lack of significance does not sufficiently proof that the differences between the RSME for the different models are zero and the superiority of the linear OLS model can not be generalized. The lack of significant differences among the alternative estimators may reflect a lack of sample size adequate to detect important differences among the estimators employed. Further studies with larger case number are necessary to confirm the results. Specification of an adequate regression models requires a careful examination of the characteristics of the data. Estimation of standard errors and confidence intervals by nonparametric methods which are robust against deviations from the normal distribution and the homoscedasticity of residuals are suitable alternatives to the transformation of the skew distributed dependent variable. Further studies with more adequate case numbers are needed to confirm the results.

Tobit analysis of vehicle accident rates on interstate highways.

PubMed

Anastasopoulos, Panagiotis Ch; Tarko, Andrew P; Mannering, Fred L

2008-03-01

There has been an abundance of research that has used Poisson models and its variants (negative binomial and zero-inflated models) to improve our understanding of the factors that affect accident frequencies on roadway segments. This study explores the application of an alternate method, tobit regression, by viewing vehicle accident rates directly (instead of frequencies) as a continuous variable that is left-censored at zero. Using data from vehicle accidents on Indiana interstates, the estimation results show that many factors relating to pavement condition, roadway geometrics and traffic characteristics significantly affect vehicle accident rates.

Reliability of environmental sampling culture results using the negative binomial intraclass correlation coefficient.

PubMed

Aly, Sharif S; Zhao, Jianyang; Li, Ben; Jiang, Jiming

2014-01-01

The Intraclass Correlation Coefficient (ICC) is commonly used to estimate the similarity between quantitative measures obtained from different sources. Overdispersed data is traditionally transformed so that linear mixed model (LMM) based ICC can be estimated. A common transformation used is the natural logarithm. The reliability of environmental sampling of fecal slurry on freestall pens has been estimated for Mycobacterium avium subsp. paratuberculosis using the natural logarithm transformed culture results. Recently, the negative binomial ICC was defined based on a generalized linear mixed model for negative binomial distributed data. The current study reports on the negative binomial ICC estimate which includes fixed effects using culture results of environmental samples. Simulations using a wide variety of inputs and negative binomial distribution parameters (r; p) showed better performance of the new negative binomial ICC compared to the ICC based on LMM even when negative binomial data was logarithm, and square root transformed. A second comparison that targeted a wider range of ICC values showed that the mean of estimated ICC closely approximated the true ICC.

Area under the curve predictions of dalbavancin, a new lipoglycopeptide agent, using the end of intravenous infusion concentration data point by regression analyses such as linear, log-linear and power models.

PubMed

Bhamidipati, Ravi Kanth; Syed, Muzeeb; Mullangi, Ramesh; Srinivas, Nuggehally

2018-02-01

1. Dalbavancin, a lipoglycopeptide, is approved for treating gram-positive bacterial infections. Area under plasma concentration versus time curve (AUC inf ) of dalbavancin is a key parameter and AUC inf /MIC ratio is a critical pharmacodynamic marker. 2. Using end of intravenous infusion concentration (i.e. C max ) C max versus AUC inf relationship for dalbavancin was established by regression analyses (i.e. linear, log-log, log-linear and power models) using 21 pairs of subject data. 3. The predictions of the AUC inf were performed using published C max data by application of regression equations. The quotient of observed/predicted values rendered fold difference. The mean absolute error (MAE)/root mean square error (RMSE) and correlation coefficient (r) were used in the assessment. 4. MAE and RMSE values for the various models were comparable. The C max versus AUC inf exhibited excellent correlation (r > 0.9488). The internal data evaluation showed narrow confinement (0.84-1.14-fold difference) with a RMSE < 10.3%. The external data evaluation showed that the models predicted AUC inf with a RMSE of 3.02-27.46% with fold difference largely contained within 0.64-1.48. 5. Regardless of the regression models, a single time point strategy of using C max (i.e. end of 30-min infusion) is amenable as a prospective tool for predicting AUC inf of dalbavancin in patients.

Proposed standard-weight (W(s)) equations for kokanee, golden trout and bull trout

USGS Publications Warehouse

Hyatt, M.H.; Hubert, W.A.

2000-01-01

We developed standard-weight (W(s)) equations for kokanee (lacustrine Oncorhynchus nerka), golden trout (O. aguabonita), and bull trout (Salvelinus confluentus) using the regression-line-percentile technique. The W(s) equation for kokanee of 120-550 mm TL is log10 W(s) = -5.062 + 3.033 log10 TL, when W(s) is in grams and TL is total length in millimeters; the English-unit equivalent is log10 W(s) = -3.458 + 3.033 log10 TL, when W(s) is in pounds and TL is total length in inches. The W(s) equation for golden trout of 120-530 mm TL is log10 W(s) = -5.088 + 3.041 log10 TL, with the English-unit equivalent being log10 W(s) = -3.473 + 3.041 log10 TL. The W(s) equation for bull trout of 120-850 mm TL is log10 W(s) = -5.327 + 3.115 log10 TL, with the English-unit equivalent being log10 W(s) = -3.608 + 3.115 log10 TL.

Estimating the magnitude of annual peak discharges with recurrence intervals between 1.1 and 3.0 years for rural, unregulated streams in West Virginia

USGS Publications Warehouse

Wiley, Jeffrey B.; Atkins, John T.; Newell, Dawn A.

2002-01-01

Multiple and simple least-squares regression models for the log10-transformed 1.5- and 2-year recurrence intervals of peak discharges with independent variables describing the basin characteristics (log10-transformed and untransformed) for 236 streamflow-gaging stations were evaluated, and the regression residuals were plotted as areal distributions that defined three regions in West Virginia designated as East, North, and South. Regional equations for the 1.1-, 1.2-, 1.3-, 1.4-, 1.5-, 1.6-, 1.7-, 1.8-, 1.9-, 2.0-, 2.5-, and 3-year recurrence intervals of peak discharges were determined by generalized least-squares regression. Log10-transformed drainage area was the most significant independent variable for all regions. Equations developed in this study are applicable only to rural, unregulated streams within the boundaries of West Virginia. The accuracies of estimating equations are quantified by measuring the average prediction error (from 27.4 to 52.4 percent) and equivalent years of record (from 1.1 to 3.4 years).

On the use of log-transformation vs. nonlinear regression for analyzing biological power laws

USGS Publications Warehouse

Xiao, X.; White, E.P.; Hooten, M.B.; Durham, S.L.

2011-01-01

Power-law relationships are among the most well-studied functional relationships in biology. Recently the common practice of fitting power laws using linear regression (LR) on log-transformed data has been criticized, calling into question the conclusions of hundreds of studies. It has been suggested that nonlinear regression (NLR) is preferable, but no rigorous comparison of these two methods has been conducted. Using Monte Carlo simulations, we demonstrate that the error distribution determines which method performs better, with NLR better characterizing data with additive, homoscedastic, normal error and LR better characterizing data with multiplicative, heteroscedastic, lognormal error. Analysis of 471 biological power laws shows that both forms of error occur in nature. While previous analyses based on log-transformation appear to be generally valid, future analyses should choose methods based on a combination of biological plausibility and analysis of the error distribution. We provide detailed guidelines and associated computer code for doing so, including a model averaging approach for cases where the error structure is uncertain. ?? 2011 by the Ecological Society of America.

A comparison of observation-level random effect and Beta-Binomial models for modelling overdispersion in Binomial data in ecology & evolution.

PubMed

Harrison, Xavier A

2015-01-01

Overdispersion is a common feature of models of biological data, but researchers often fail to model the excess variation driving the overdispersion, resulting in biased parameter estimates and standard errors. Quantifying and modeling overdispersion when it is present is therefore critical for robust biological inference. One means to account for overdispersion is to add an observation-level random effect (OLRE) to a model, where each data point receives a unique level of a random effect that can absorb the extra-parametric variation in the data. Although some studies have investigated the utility of OLRE to model overdispersion in Poisson count data, studies doing so for Binomial proportion data are scarce. Here I use a simulation approach to investigate the ability of both OLRE models and Beta-Binomial models to recover unbiased parameter estimates in mixed effects models of Binomial data under various degrees of overdispersion. In addition, as ecologists often fit random intercept terms to models when the random effect sample size is low (<5 levels), I investigate the performance of both model types under a range of random effect sample sizes when overdispersion is present. Simulation results revealed that the efficacy of OLRE depends on the process that generated the overdispersion; OLRE failed to cope with overdispersion generated from a Beta-Binomial mixture model, leading to biased slope and intercept estimates, but performed well for overdispersion generated by adding random noise to the linear predictor. Comparison of parameter estimates from an OLRE model with those from its corresponding Beta-Binomial model readily identified when OLRE were performing poorly due to disagreement between effect sizes, and this strategy should be employed whenever OLRE are used for Binomial data to assess their reliability. Beta-Binomial models performed well across all contexts, but showed a tendency to underestimate effect sizes when modelling non-Beta-Binomial data. Finally, both OLRE and Beta-Binomial models performed poorly when models contained <5 levels of the random intercept term, especially for estimating variance components, and this effect appeared independent of total sample size. These results suggest that OLRE are a useful tool for modelling overdispersion in Binomial data, but that they do not perform well in all circumstances and researchers should take care to verify the robustness of parameter estimates of OLRE models.

Proposed standard-weight equations for brook trout

USGS Publications Warehouse

Hyatt, M.W.; Hubert, W.A.

2001-01-01

Weight and length data were obtained for 113 populations of brook trout Salvelinus fontinalis across the species' geographic range in North America to estimate a standard-weight (Ws) equation for this species. Estimation was done by applying the regression-line-percentile technique to fish of 120-620 mm total length (TL). The proposed metric-unit (g and mm) equation is log10Ws = -5.186 + 3.103 log10TL; the English-unit (lb and in) equivalent is log10Ws = -3.483 + 3.103 log10TL. No systematic length bias was evident in the relative-weight values calculated from these equations.

A Language-Independent Approach to Automatic Text Difficulty Assessment for Second-Language Learners

DTIC Science & Technology

2013-08-01

best-suited for regression. Our baseline uses z-normalized shallow length features and TF -LOG weighted vectors on bag-of-words for Arabic, Dari...length features and TF -LOG weighted vectors on bag-of-words for Arabic, Dari, English and Pashto. We compare Support Vector Machines and the Margin...football, whereas they are much less common in documents about opera). We used TF -LOG weighted word frequencies on bag-of-words for each document

Silanols, a New Class of Antimicrobial Agent

DTIC Science & Technology

2006-04-01

carbinols against the four bacteria was log (1/MLC) = 0.670 log P + 0.0035 ∆ν -1.836, n = 282, r = 0.96, s = 0.22. This equation and a significantly...activity relationship of antimicrobial agents by means of equations [8] based on a method proposed by Hansch and Fujita in 1964 [1]. This multiple...correlation equations between their antimicrobial activities and structural properties, log P and H-bond acidity, were created by a multiple regression

Review and Recommendations for Zero-inflated Count Regression Modeling of Dental Caries Indices in Epidemiological Studies

PubMed Central

Stamm, John W.; Long, D. Leann; Kincade, Megan E.

2012-01-01

Over the past five to ten years, zero-inflated count regression models have been increasingly applied to the analysis of dental caries indices (e.g., DMFT, dfms, etc). The main reason for that is linked to the broad decline in children’s caries experience, such that dmf and DMF indices more frequently generate low or even zero counts. This article specifically reviews the application of zero-inflated Poisson and zero-inflated negative binomial regression models to dental caries, with emphasis on the description of the models and the interpretation of fitted model results given the study goals. The review finds that interpretations provided in the published caries research are often imprecise or inadvertently misleading, particularly with respect to failing to discriminate between inference for the class of susceptible persons defined by such models and inference for the sampled population in terms of overall exposure effects. Recommendations are provided to enhance the use as well as the interpretation and reporting of results of count regression models when applied to epidemiological studies of dental caries. PMID:22710271

M-Bonomial Coefficients and Their Identities

ERIC Educational Resources Information Center

Asiru, Muniru A.

2010-01-01

In this note, we introduce M-bonomial coefficients or (M-bonacci binomial coefficients). These are similar to the binomial and the Fibonomial (or Fibonacci-binomial) coefficients and can be displayed in a triangle similar to Pascal's triangle from which some identities become obvious.

The association between major depression prevalence and sex becomes weaker with age.

PubMed

Patten, Scott B; Williams, Jeanne V A; Lavorato, Dina H; Wang, Jian Li; Bulloch, Andrew G M; Sajobi, Tolulope

2016-02-01

Women have a higher prevalence of major depressive episodes (MDE) than men, and the annual prevalence of MDE declines with age. Age by sex interactions may occur (a weakening of the sex effect with age), but are easily overlooked since individual studies lack statistical power to detect interactions. The objective of this study was to evaluate age by sex interactions in MDE prevalence. In Canada, a series of 10 national surveys conducted between 1996 and 2013 assessed MDE prevalence in respondents over the age of 14. Treating age as a continuous variable, binomial and linear regression was used to model age by sex interactions in each survey. To increase power, the survey-specific interaction coefficients were then pooled using meta-analytic methods. The estimated interaction terms were homogeneous. In the binomial regression model I (2) was 31.2 % and was not statistically significant (Q statistic = 13.1, df = 9, p = 0.159). The pooled estimate (-0.004) was significant (z = 3.13, p = 0.002), indicating that the effect of sex became weaker with increasing age. This resulted in near disappearance of the sex difference in the 75+ age group. This finding was also supported by an examination of age- and sex-specific estimates pooled across the surveys. The association of MDE prevalence with sex becomes weaker with age. The interaction may reflect biological effect modification. Investigators should test for, and consider inclusion of age by sex interactions in epidemiological analyses of MDE prevalence.

Association between month of birth and melanoma risk: fact or fiction?

PubMed

Fiessler, Cornelia; Pfahlberg, Annette B; Keller, Andrea K; Radespiel-Tröger, Martin; Uter, Wolfgang; Gefeller, Olaf

2017-04-01

Evidence on the effect of ultraviolet radiation (UVR) exposure in infancy on melanoma risk in later life is scarce. Three recent studies suggest that people born in spring carry a higher melanoma risk. Our study aimed at verifying whether such a seasonal pattern of melanoma risk actually exists. Data from the population-based Cancer Registry Bavaria (CRB) on the birth months of 28 374 incident melanoma cases between 2002 and 2012 were analysed and compared with data from the Bavarian State Office for Statistics and Data Processing on the birth month distribution in the Bavarian population. Crude and adjusted analyses using negative binomial regression models were performed in the total study group and supplemented by several subgroup analyses. In the crude analysis, the birth months March-May were over-represented among melanoma cases. Negative binomial regression models adjusted only for sex and birth year revealed a seasonal association between melanoma risk and birth month with 13-21% higher relative incidence rates for March, April and May compared with the reference December. However, after additionally adjusting for the birth month distribution of the Bavarian population, these risk estimates decreased markedly and no association with the birth month was observed any more. Similar results emerged in all subgroup analyses. Our large registry-based study provides no evidence that people born in spring carry a higher risk for developing melanoma in later life and thus lends no support to the hypothesis of higher UVR susceptibility during the first months of life. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association

Dispersion models and sampling of cacao mirid bug Sahlbergella singularis (Hemiptera: Miridae) on Theobroma Cacao in southern Cameroon.

PubMed

Bisseleua, D H B; Vidal, Stefan

2011-02-01

The spatio-temporal distribution of Sahlbergella singularis Haglung, a major pest of cacao trees (Theobroma cacao) (Malvaceae), was studied for 2 yr in traditional cacao forest gardens in the humid forest area of southern Cameroon. The first objective was to analyze the dispersion of this insect on cacao trees. The second objective was to develop sampling plans based on fixed levels of precision for estimating S. singularis populations. The following models were used to analyze the data: Taylor's power law, Iwao's patchiness regression, the Nachman model, and the negative binomial distribution. Our results document that Taylor's power law was a better fit for the data than the Iwao and Nachman models. Taylor's b and Iwao's β were both significantly >1, indicating that S. singularis aggregated on specific trees. This result was further supported by the calculated common k of 1.75444. Iwao's α was significantly <0, indicating that the basic distribution component of S. singularis was the individual insect. Comparison of negative binomial (NBD) and Nachman models indicated that the NBD model was appropriate for studying S. singularis distribution. Optimal sample sizes for fixed precision levels of 0.10, 0.15, and 0.25 were estimated with Taylor's regression coefficients. Required sample sizes increased dramatically with increasing levels of precision. This is the first study on S. singularis dispersion in cacao plantations. Sampling plans, presented here, should be a tool for research on population dynamics and pest management decisions of mirid bugs on cacao. © 2011 Entomological Society of America

Individual-level exposure to disaster, neighborhood environmental characteristics, and their independent and combined associations with depressive symptoms in women.

PubMed

Gaston, Symielle A; Volaufova, Julia; Peters, Edward S; Ferguson, Tekeda F; Robinson, William T; Nugent, Nicole; Trapido, Edward J; Rung, Ariane L

2017-09-01

The severity of the stress response to experiencing disaster depends on individual exposure and background stress prior to the event. To date, there is limited research on the interaction between neighborhood environmental stress and experiencing an oil spill, and their effects on depression. The objective of the current study was to assess if the association between exposure to the Deepwater Horizon Oil Spill (DHOS) and depressive symptoms varied by neighborhood characteristics. US Census data (2010) and longitudinal data collected in two waves (2012-2014 and 2014-2016) from female residents [N = 889 (Wave I), 737 (Wave II)] of an area highly affected by the DHOS were analyzed. Multilevel and individual-level negative binomial regressions were performed to estimate associations with depressive symptoms in both waves. An interaction term was included to estimate effect modification of the association between DHOS exposure and depressive symptoms by neighborhood characteristics. Generalized estimating equations were applied to the negative binomial regression testing longitudinal associations. Census tract-level neighborhood characteristics were not associated with depressive symptoms. Exposure to the DHOS and neighborhood physical disorder were associated with depressive symptoms cross-sectionally. There was no evidence of effect modification; however, physical/environmental exposure to the DHOS was associated with increased depressive symptoms only among women living in areas with physical disorder. Exposure to the DHOS remained associated with depressive symptoms over time. Findings support the enduring consequences of disaster exposure on depressive symptoms in women and identify potential targets for post-disaster intervention based on residential characteristics.

Not in My Back Yard: A Comparative Analysis of Crime Around Publicly Funded Drug Treatment Centers, Liquor Stores, Convenience Stores, and Corner Stores in One Mid-Atlantic City

PubMed Central

Furr-Holden, C. Debra M.; Milam, Adam J.; Nesoff, Elizabeth D.; Johnson, Renee M.; Fakunle, David O.; Jennings, Jacky M.; Thorpe, Roland J.

2016-01-01

Objective: This research examined whether publicly funded drug treatment centers (DTCs) were associated with violent crime in excess of the violence happening around other commercial businesses. Method: Violent crime data and locations of community entities were geocoded and mapped. DTCs and other retail outlets were matched based on a Neighborhood Disadvantage score at the census tract level. Street network buffers ranging from 100 to 1,400 feet were placed around each location. Negative binomial regression models were used to estimate the relationship between the count of violent crimes and the distance from each business type. Results: Compared with the mean count of violent crime around drug treatment centers, the mean count of violent crime (M = 2.87) was significantly higher around liquor stores (M = 3.98; t test; p < .01) and corner stores (M = 3.78; t test; p < .01), and there was no statistically significant difference between the count around convenience stores (M = 2.65; t test; p = .32). In the adjusted negative binomial regression models, there was a negative and significant relationship between the count of violent crime and the distance from drug treatment centers (β = -.069, p < .01), liquor stores (β = -.081, p < .01), corner stores (β = -.116, p < .01), and convenience stores (β = -.154, p < .01). Conclusions: Violent crime associated with drug treatment centers is similar to that associated with liquor stores and is less frequent than that associated with convenience stores and corner stores. PMID:26751351

Serum Spot 14 concentration is negatively associated with thyroid-stimulating hormone level

PubMed Central

Chen, Yen-Ting; Tseng, Fen-Yu; Chen, Pei-Lung; Chi, Yu-Chao; Han, Der-Sheng; Yang, Wei-Shiung

2016-01-01

Abstract Spot 14 (S14) is a protein involved in fatty acid synthesis and was shown to be induced by thyroid hormone in rat liver. However, the presence of S14 in human serum and its relations with thyroid function status have not been investigated. The objectives of this study were to compare serum S14 concentrations in patients with hyperthyroidism or euthyroidism and to evaluate the associations between serum S14 and free thyroxine (fT4) or thyroid-stimulating hormone (TSH) levels. We set up an immunoassay for human serum S14 concentrations and compared its levels between hyperthyroid and euthyroid subjects. Twenty-six hyperthyroid patients and 29 euthyroid individuals were recruited. Data of all patients were pooled for the analysis of the associations between the levels of S14 and fT4, TSH, or quartile of TSH. The hyperthyroid patients had significantly higher serum S14 levels than the euthyroid subjects (median [Q1, Q3]: 975 [669, 1612] ng/mL vs 436 [347, 638] ng/mL, P < 0.001). In univariate linear regression, the log-transformed S14 level (logS14) was positively associated with fT4 but negatively associated with creatinine (Cre), total cholesterol (T-C), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and TSH. The positive associations between logS14 and fT4 and the negative associations between logS14 and Cre, TG, T-C, or TSH remained significant after adjustment with sex and age. These associations were prominent in females but not in males. The logS14 levels were negatively associated with the TSH levels grouped by quartile (ß = −0.3020, P < 0.001). The association between logS14 and TSH quartile persisted after adjustment with sex and age (ß = −0.2828, P = 0.001). In stepwise multivariate regression analysis, only TSH grouped by quartile remained significantly associated with logS14 level. We developed an ELISA to measure serum S14 levels in human. Female patients with hyperthyroidism had higher serum S14 levels than the female subjects with euthyroidism. The serum logS14 concentrations were negatively associated with TSH levels. Changes of serum S14 level in the whole thyroid function spectrum deserve further investigation. PMID:27749565

Performance and structure of single-mode bosonic codes

NASA Astrophysics Data System (ADS)

Albert, Victor V.; Noh, Kyungjoo; Duivenvoorden, Kasper; Young, Dylan J.; Brierley, R. T.; Reinhold, Philip; Vuillot, Christophe; Li, Linshu; Shen, Chao; Girvin, S. M.; Terhal, Barbara M.; Jiang, Liang

2018-03-01

The early Gottesman, Kitaev, and Preskill (GKP) proposal for encoding a qubit in an oscillator has recently been followed by cat- and binomial-code proposals. Numerically optimized codes have also been proposed, and we introduce codes of this type here. These codes have yet to be compared using the same error model; we provide such a comparison by determining the entanglement fidelity of all codes with respect to the bosonic pure-loss channel (i.e., photon loss) after the optimal recovery operation. We then compare achievable communication rates of the combined encoding-error-recovery channel by calculating the channel's hashing bound for each code. Cat and binomial codes perform similarly, with binomial codes outperforming cat codes at small loss rates. Despite not being designed to protect against the pure-loss channel, GKP codes significantly outperform all other codes for most values of the loss rate. We show that the performance of GKP and some binomial codes increases monotonically with increasing average photon number of the codes. In order to corroborate our numerical evidence of the cat-binomial-GKP order of performance occurring at small loss rates, we analytically evaluate the quantum error-correction conditions of those codes. For GKP codes, we find an essential singularity in the entanglement fidelity in the limit of vanishing loss rate. In addition to comparing the codes, we draw parallels between binomial codes and discrete-variable systems. First, we characterize one- and two-mode binomial as well as multiqubit permutation-invariant codes in terms of spin-coherent states. Such a characterization allows us to introduce check operators and error-correction procedures for binomial codes. Second, we introduce a generalization of spin-coherent states, extending our characterization to qudit binomial codes and yielding a multiqudit code.

Quantifying the safety effects of horizontal curves on two-way, two-lane rural roads.

PubMed

Gooch, Jeffrey P; Gayah, Vikash V; Donnell, Eric T

2016-07-01

The objective of this study is to quantify the safety performance of horizontal curves on two-way, two-lane rural roads relative to tangent segments. Past research is limited by small samples sizes, outdated statistical evaluation methods, and unreported standard errors. This study overcomes these drawbacks by using the propensity scores-potential outcomes framework. The impact of adjacent curves on horizontal curve safety is also explored using a cross-sectional regression model of only horizontal curves. The models estimated in the present study used eight years of crash data (2005-2012) obtained from over 10,000 miles of state-owned two-lane rural roads in Pennsylvania. These data included information on roadway geometry (e.g., horizontal curvature, lane width, and shoulder width), traffic volume, roadside hazard rating, and the presence of various low-cost safety countermeasures (e.g., centerline and shoulder rumble strips, curve and intersection warning pavement markings, and aggressive driving pavement dots). Crash prediction is performed by means of mixed effects negative binomial regression using the explanatory variables noted previously, as well as attributes of adjacent horizontal curves. The results indicate that both the presence of a horizontal curve and its degree of curvature must be considered when predicting the frequency of total crashes on horizontal curves. Both are associated with an increase in crash frequency, which is consistent with previous findings in the literature. Mixed effects negative binomial regression models for total crash frequency on horizontal curves indicate that the distance to adjacent curves is not statistically significant. However, the degree of curvature of adjacent curves in close proximity (within 0.75 miles) was found to be statistically significant and negatively correlated with crash frequency on the subject curve. This is logical, as drivers exiting a sharp curve are likely to be driving slower and with more awareness as they approach the next horizontal curve. Copyright © 2016 Elsevier Ltd. All rights reserved.

Using beta binomials to estimate classification uncertainty for ensemble models.

PubMed

Clark, Robert D; Liang, Wenkel; Lee, Adam C; Lawless, Michael S; Fraczkiewicz, Robert; Waldman, Marvin

2014-01-01

Quantitative structure-activity (QSAR) models have enormous potential for reducing drug discovery and development costs as well as the need for animal testing. Great strides have been made in estimating their overall reliability, but to fully realize that potential, researchers and regulators need to know how confident they can be in individual predictions. Submodels in an ensemble model which have been trained on different subsets of a shared training pool represent multiple samples of the model space, and the degree of agreement among them contains information on the reliability of ensemble predictions. For artificial neural network ensembles (ANNEs) using two different methods for determining ensemble classification - one using vote tallies and the other averaging individual network outputs - we have found that the distribution of predictions across positive vote tallies can be reasonably well-modeled as a beta binomial distribution, as can the distribution of errors. Together, these two distributions can be used to estimate the probability that a given predictive classification will be in error. Large data sets comprised of logP, Ames mutagenicity, and CYP2D6 inhibition data are used to illustrate and validate the method. The distributions of predictions and errors for the training pool accurately predicted the distribution of predictions and errors for large external validation sets, even when the number of positive and negative examples in the training pool were not balanced. Moreover, the likelihood of a given compound being prospectively misclassified as a function of the degree of consensus between networks in the ensemble could in most cases be estimated accurately from the fitted beta binomial distributions for the training pool. Confidence in an individual predictive classification by an ensemble model can be accurately assessed by examining the distributions of predictions and errors as a function of the degree of agreement among the constituent submodels. Further, ensemble uncertainty estimation can often be improved by adjusting the voting or classification threshold based on the parameters of the error distribution. Finally, the profiles for models whose predictive uncertainty estimates are not reliable provide clues to that effect without the need for comparison to an external test set.

Statistical Models for the Analysis and Design of Digital Polymerase Chain Reaction (dPCR) Experiments.

PubMed

Dorazio, Robert M; Hunter, Margaret E

2015-11-03

Statistical methods for the analysis and design of experiments using digital PCR (dPCR) have received only limited attention and have been misused in many instances. To address this issue and to provide a more general approach to the analysis of dPCR data, we describe a class of statistical models for the analysis and design of experiments that require quantification of nucleic acids. These models are mathematically equivalent to generalized linear models of binomial responses that include a complementary, log-log link function and an offset that is dependent on the dPCR partition volume. These models are both versatile and easy to fit using conventional statistical software. Covariates can be used to specify different sources of variation in nucleic acid concentration, and a model's parameters can be used to quantify the effects of these covariates. For purposes of illustration, we analyzed dPCR data from different types of experiments, including serial dilution, evaluation of copy number variation, and quantification of gene expression. We also showed how these models can be used to help design dPCR experiments, as in selection of sample sizes needed to achieve desired levels of precision in estimates of nucleic acid concentration or to detect differences in concentration among treatments with prescribed levels of statistical power.

Matrix diffusion coefficients in volcanic rocks at the Nevada test site: influence of matrix porosity, matrix permeability, and fracture coating minerals.

PubMed

Reimus, Paul W; Callahan, Timothy J; Ware, S Doug; Haga, Marc J; Counce, Dale A

2007-08-15

Diffusion cell experiments were conducted to measure nonsorbing solute matrix diffusion coefficients in forty-seven different volcanic rock matrix samples from eight different locations (with multiple depth intervals represented at several locations) at the Nevada Test Site. The solutes used in the experiments included bromide, iodide, pentafluorobenzoate (PFBA), and tritiated water ((3)HHO). The porosity and saturated permeability of most of the diffusion cell samples were measured to evaluate the correlation of these two variables with tracer matrix diffusion coefficients divided by the free-water diffusion coefficient (D(m)/D*). To investigate the influence of fracture coating minerals on matrix diffusion, ten of the diffusion cells represented paired samples from the same depth interval in which one sample contained a fracture surface with mineral coatings and the other sample consisted of only pure matrix. The log of (D(m)/D*) was found to be positively correlated with both the matrix porosity and the log of matrix permeability. A multiple linear regression analysis indicated that both parameters contributed significantly to the regression at the 95% confidence level. However, the log of the matrix diffusion coefficient was more highly-correlated with the log of matrix permeability than with matrix porosity, which suggests that matrix diffusion coefficients, like matrix permeabilities, have a greater dependence on the interconnectedness of matrix porosity than on the matrix porosity itself. The regression equation for the volcanic rocks was found to provide satisfactory predictions of log(D(m)/D*) for other types of rocks with similar ranges of matrix porosity and permeability as the volcanic rocks, but it did a poorer job predicting log(D(m)/D*) for rocks with lower porosities and/or permeabilities. The presence of mineral coatings on fracture walls did not appear to have a significant effect on matrix diffusion in the ten paired diffusion cell experiments.

Matrix diffusion coefficients in volcanic rocks at the Nevada test site: Influence of matrix porosity, matrix permeability, and fracture coating minerals

NASA Astrophysics Data System (ADS)

Reimus, Paul W.; Callahan, Timothy J.; Ware, S. Doug; Haga, Marc J.; Counce, Dale A.

2007-08-01

Diffusion cell experiments were conducted to measure nonsorbing solute matrix diffusion coefficients in forty-seven different volcanic rock matrix samples from eight different locations (with multiple depth intervals represented at several locations) at the Nevada Test Site. The solutes used in the experiments included bromide, iodide, pentafluorobenzoate (PFBA), and tritiated water ( 3HHO). The porosity and saturated permeability of most of the diffusion cell samples were measured to evaluate the correlation of these two variables with tracer matrix diffusion coefficients divided by the free-water diffusion coefficient ( Dm/ D*). To investigate the influence of fracture coating minerals on matrix diffusion, ten of the diffusion cells represented paired samples from the same depth interval in which one sample contained a fracture surface with mineral coatings and the other sample consisted of only pure matrix. The log of ( Dm/ D*) was found to be positively correlated with both the matrix porosity and the log of matrix permeability. A multiple linear regression analysis indicated that both parameters contributed significantly to the regression at the 95% confidence level. However, the log of the matrix diffusion coefficient was more highly-correlated with the log of matrix permeability than with matrix porosity, which suggests that matrix diffusion coefficients, like matrix permeabilities, have a greater dependence on the interconnectedness of matrix porosity than on the matrix porosity itself. The regression equation for the volcanic rocks was found to provide satisfactory predictions of log( Dm/ D*) for other types of rocks with similar ranges of matrix porosity and permeability as the volcanic rocks, but it did a poorer job predicting log( Dm/ D*) for rocks with lower porosities and/or permeabilities. The presence of mineral coatings on fracture walls did not appear to have a significant effect on matrix diffusion in the ten paired diffusion cell experiments.

Serum bilirubin concentration is associated with eGFR and urinary albumin excretion in patients with type 1 diabetes mellitus.

PubMed

Nishimura, Takeshi; Tanaka, Masami; Sekioka, Risa; Itoh, Hiroshi

2015-01-01

Although relationships of serum bilirubin concentration with estimated glomerular filtration rate (eGFR) and urinary albumin excretion (UAE) in patients with type 2 diabetes have been reported, whether such relationships exist in patients with type 1 diabetes is unknown. A total of 123 patients with type 1 diabetes were investigated in this cross-sectional study. The relationship between bilirubin (total and indirect) concentrations and log(UAE) as well as eGFR was examined by Pearson's correlation analyses. Multivariate regression analyses were used to assess the association of bilirubin (total and indirect) with eGFR as well as log(UAE). A positive correlation was found between serum bilirubin concentration and eGFR; total bilirubin (r=0.223, p=0.013), indirect bilirubin (r=0.244, p=0.007). A negative correlation was found between serum bilirubin concentration and log(UAE); total bilirubin (r=-0.258, p=0.005), indirect bilirubin (r=-0.271, p=0.003). Multivariate regression analyses showed that indirect bilirubin concentration was an independent determinant of eGFR and log(UAE). Bilirubin concentration is associated with both eGFR and log(UAE) in patients with type 1 diabetes. Bilirubin might have a protective role in the progression of type 1 diabetic nephropathy. Copyright © 2015 Elsevier Inc. All rights reserved.

Prediction of kinase-inhibitor binding affinity using energetic parameters

PubMed Central

Usha, Singaravelu; Selvaraj, Samuel

2016-01-01

The combination of physicochemical properties and energetic parameters derived from protein-ligand complexes play a vital role in determining the biological activity of a molecule. In the present work, protein-ligand interaction energy along with logP values was used to predict the experimental log (IC50) values of 25 different kinase-inhibitors using multiple regressions which gave a correlation coefficient of 0.93. The regression equation obtained was tested on 93 kinase-inhibitor complexes and an average deviation of 0.92 from the experimental log IC50 values was shown. The same set of descriptors was used to predict binding affinities for a test set of five individual kinase families, with correlation values > 0.9. We show that the protein-ligand interaction energies and partition coefficient values form the major deterministic factors for binding affinity of the ligand for its receptor. PMID:28149052

Adjusting for overdispersion in piecewise exponential regression models to estimate excess mortality rate in population-based research.

PubMed

Luque-Fernandez, Miguel Angel; Belot, Aurélien; Quaresma, Manuela; Maringe, Camille; Coleman, Michel P; Rachet, Bernard

2016-10-01

In population-based cancer research, piecewise exponential regression models are used to derive adjusted estimates of excess mortality due to cancer using the Poisson generalized linear modelling framework. However, the assumption that the conditional mean and variance of the rate parameter given the set of covariates x i are equal is strong and may fail to account for overdispersion given the variability of the rate parameter (the variance exceeds the mean). Using an empirical example, we aimed to describe simple methods to test and correct for overdispersion. We used a regression-based score test for overdispersion under the relative survival framework and proposed different approaches to correct for overdispersion including a quasi-likelihood, robust standard errors estimation, negative binomial regression and flexible piecewise modelling. All piecewise exponential regression models showed the presence of significant inherent overdispersion (p-value <0.001). However, the flexible piecewise exponential model showed the smallest overdispersion parameter (3.2 versus 21.3) for non-flexible piecewise exponential models. We showed that there were no major differences between methods. However, using a flexible piecewise regression modelling, with either a quasi-likelihood or robust standard errors, was the best approach as it deals with both, overdispersion due to model misspecification and true or inherent overdispersion.

Estimating a Logistic Discrimination Functions When One of the Training Samples Is Subject to Misclassification: A Maximum Likelihood Approach.

PubMed

Nagelkerke, Nico; Fidler, Vaclav

2015-01-01

The problem of discrimination and classification is central to much of epidemiology. Here we consider the estimation of a logistic regression/discrimination function from training samples, when one of the training samples is subject to misclassification or mislabeling, e.g. diseased individuals are incorrectly classified/labeled as healthy controls. We show that this leads to zero-inflated binomial model with a defective logistic regression or discrimination function, whose parameters can be estimated using standard statistical methods such as maximum likelihood. These parameters can be used to estimate the probability of true group membership among those, possibly erroneously, classified as controls. Two examples are analyzed and discussed. A simulation study explores properties of the maximum likelihood parameter estimates and the estimates of the number of mislabeled observations.

QNB: differential RNA methylation analysis for count-based small-sample sequencing data with a quad-negative binomial model.

PubMed

Liu, Lian; Zhang, Shao-Wu; Huang, Yufei; Meng, Jia

2017-08-31

As a newly emerged research area, RNA epigenetics has drawn increasing attention recently for the participation of RNA methylation and other modifications in a number of crucial biological processes. Thanks to high throughput sequencing techniques, such as, MeRIP-Seq, transcriptome-wide RNA methylation profile is now available in the form of count-based data, with which it is often of interests to study the dynamics at epitranscriptomic layer. However, the sample size of RNA methylation experiment is usually very small due to its costs; and additionally, there usually exist a large number of genes whose methylation level cannot be accurately estimated due to their low expression level, making differential RNA methylation analysis a difficult task. We present QNB, a statistical approach for differential RNA methylation analysis with count-based small-sample sequencing data. Compared with previous approaches such as DRME model based on a statistical test covering the IP samples only with 2 negative binomial distributions, QNB is based on 4 independent negative binomial distributions with their variances and means linked by local regressions, and in the way, the input control samples are also properly taken care of. In addition, different from DRME approach, which relies only the input control sample only for estimating the background, QNB uses a more robust estimator for gene expression by combining information from both input and IP samples, which could largely improve the testing performance for very lowly expressed genes. QNB showed improved performance on both simulated and real MeRIP-Seq datasets when compared with competing algorithms. And the QNB model is also applicable to other datasets related RNA modifications, including but not limited to RNA bisulfite sequencing, m 1 A-Seq, Par-CLIP, RIP-Seq, etc.

Problems on Divisibility of Binomial Coefficients

ERIC Educational Resources Information Center

Osler, Thomas J.; Smoak, James

2004-01-01

Twelve unusual problems involving divisibility of the binomial coefficients are represented in this article. The problems are listed in "The Problems" section. All twelve problems have short solutions which are listed in "The Solutions" section. These problems could be assigned to students in any course in which the binomial theorem and Pascal's…

Application of binomial-edited CPMG to shale characterization

USGS Publications Warehouse

Washburn, Kathryn E.; Birdwell, Justin E.

2014-01-01

Unconventional shale resources may contain a significant amount of hydrogen in organic solids such as kerogen, but it is not possible to directly detect these solids with many NMR systems. Binomial-edited pulse sequences capitalize on magnetization transfer between solids, semi-solids, and liquids to provide an indirect method of detecting solid organic materials in shales. When the organic solids can be directly measured, binomial-editing helps distinguish between different phases. We applied a binomial-edited CPMG pulse sequence to a range of natural and experimentally-altered shale samples. The most substantial signal loss is seen in shales rich in organic solids while fluids associated with inorganic pores seem essentially unaffected. This suggests that binomial-editing is a potential method for determining fluid locations, solid organic content, and kerogen–bitumen discrimination.

The effect of a major cigarette price change on smoking behavior in california: a zero-inflated negative binomial model.

PubMed

Sheu, Mei-Ling; Hu, Teh-Wei; Keeler, Theodore E; Ong, Michael; Sung, Hai-Yen

2004-08-01

The objective of this paper is to determine the price sensitivity of smokers in their consumption of cigarettes, using evidence from a major increase in California cigarette prices due to Proposition 10 and the Tobacco Settlement. The study sample consists of individual survey data from Behavioral Risk Factor Survey (BRFS) and price data from the Bureau of Labor Statistics between 1996 and 1999. A zero-inflated negative binomial (ZINB) regression model was applied for the statistical analysis. The statistical model showed that price did not have an effect on reducing the estimated prevalence of smoking. However, it indicated that among smokers the price elasticity was at the level of -0.46 and statistically significant. Since smoking prevalence is significantly lower than it was a decade ago, price increases are becoming less effective as an inducement for hard-core smokers to quit, although they may respond by decreasing consumption. For those who only smoke occasionally (many of them being young adults) price increases alone may not be an effective inducement to quit smoking. Additional underlying behavioral factors need to be identified so that more effective anti-smoking strategies can be developed.

Variable selection for zero-inflated and overdispersed data with application to health care demand in Germany.

PubMed

Wang, Zhu; Ma, Shuangge; Wang, Ching-Yun

2015-09-01

In health services and outcome research, count outcomes are frequently encountered and often have a large proportion of zeros. The zero-inflated negative binomial (ZINB) regression model has important applications for this type of data. With many possible candidate risk factors, this paper proposes new variable selection methods for the ZINB model. We consider maximum likelihood function plus a penalty including the least absolute shrinkage and selection operator (LASSO), smoothly clipped absolute deviation (SCAD), and minimax concave penalty (MCP). An EM (expectation-maximization) algorithm is proposed for estimating the model parameters and conducting variable selection simultaneously. This algorithm consists of estimating penalized weighted negative binomial models and penalized logistic models via the coordinated descent algorithm. Furthermore, statistical properties including the standard error formulae are provided. A simulation study shows that the new algorithm not only has more accurate or at least comparable estimation, but also is more robust than the traditional stepwise variable selection. The proposed methods are applied to analyze the health care demand in Germany using the open-source R package mpath. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The allometry of coarse root biomass: log-transformed linear regression or nonlinear regression?

PubMed

Lai, Jiangshan; Yang, Bo; Lin, Dunmei; Kerkhoff, Andrew J; Ma, Keping

2013-01-01

Precise estimation of root biomass is important for understanding carbon stocks and dynamics in forests. Traditionally, biomass estimates are based on allometric scaling relationships between stem diameter and coarse root biomass calculated using linear regression (LR) on log-transformed data. Recently, it has been suggested that nonlinear regression (NLR) is a preferable fitting method for scaling relationships. But while this claim has been contested on both theoretical and empirical grounds, and statistical methods have been developed to aid in choosing between the two methods in particular cases, few studies have examined the ramifications of erroneously applying NLR. Here, we use direct measurements of 159 trees belonging to three locally dominant species in east China to compare the LR and NLR models of diameter-root biomass allometry. We then contrast model predictions by estimating stand coarse root biomass based on census data from the nearby 24-ha Gutianshan forest plot and by testing the ability of the models to predict known root biomass values measured on multiple tropical species at the Pasoh Forest Reserve in Malaysia. Based on likelihood estimates for model error distributions, as well as the accuracy of extrapolative predictions, we find that LR on log-transformed data is superior to NLR for fitting diameter-root biomass scaling models. More importantly, inappropriately using NLR leads to grossly inaccurate stand biomass estimates, especially for stands dominated by smaller trees.

The influence of neighborhood characteristics on the relationship between discrimination and increased drug-using social ties among illicit drug users.

PubMed

Crawford, Natalie D; Borrell, Luisa N; Galea, Sandro; Ford, Chandra; Latkin, Carl; Fuller, Crystal M

2013-04-01

Social discrimination may isolate drug users into higher risk relationships, particularly in disadvantaged neighborhood environments where drug trade occurs. We used negative binomial regression accounting for clustering of individuals within their recruitment neighborhood to investigate the relationship between high-risk drug ties with various forms of social discrimination, neighborhood minority composition, poverty and education. Results show that experiencing discrimination due to drug use is significantly associated with more drug ties in neighborhoods with fewer blacks. Future social network and discrimination research should assess the role of neighborhood social cohesion.

Technology diffusion in hospitals: a log odds random effects regression model.

PubMed

Blank, Jos L T; Valdmanis, Vivian G

2015-01-01

This study identifies the factors that affect the diffusion of hospital innovations. We apply a log odds random effects regression model on hospital micro data. We introduce the concept of clustering innovations and the application of a log odds random effects regression model to describe the diffusion of technologies. We distinguish a number of determinants, such as service, physician, and environmental, financial and organizational characteristics of the 60 Dutch hospitals in our sample. On the basis of this data set on Dutch general hospitals over the period 1995-2002, we conclude that there is a relation between a number of determinants and the diffusion of innovations underlining conclusions from earlier research. Positive effects were found on the basis of the size of the hospitals, competition and a hospital's commitment to innovation. It appears that if a policy is developed to further diffuse innovations, the external effects of demand and market competition need to be examined, which would de facto lead to an efficient use of technology. For the individual hospital, instituting an innovations office appears to be the most prudent course of action. © 2013 The Authors. International Journal of Health Planning and Management published by John Wiley & Sons, Ltd.

Morphometric analyses of hominoid crania, probabilities of conspecificity and an approximation of a biological species constant.

PubMed

Thackeray, J F; Dykes, S

2016-02-01

Thackeray has previously explored the possibility of using a morphometric approach to quantify the "amount" of variation within species and to assess probabilities of conspecificity when two fossil specimens are compared, instead of "pigeon-holing" them into discrete species. In an attempt to obtain a statistical (probabilistic) definition of a species, Thackeray has recognized an approximation of a biological species constant (T=-1.61) based on the log-transformed standard error of the coefficient m (log sem) in regression analysis of cranial and other data from pairs of specimens of conspecific extant species, associated with regression equations of the form y=mx+c where m is the slope and c is the intercept, using measurements of any specimen A (x axis), and any specimen B of the same species (y axis). The log-transformed standard error of the co-efficient m (log sem) is a measure of the degree of similarity between pairs of specimens, and in this study shows central tendency around a mean value of -1.61 and standard deviation 0.10 for modern conspecific specimens. In this paper we focus attention on the need to take into account the range of difference in log sem values (Δlog sem or "delta log sem") obtained from comparisons when specimen A (x axis) is compared to B (y axis), and secondly when specimen A (y axis) is compared to B (x axis). Thackeray's approach can be refined to focus on high probabilities of conspecificity for pairs of specimens for which log sem is less than -1.61 and for which Δlog sem is less than 0.03. We appeal for the adoption of a concept here called "sigma taxonomy" (as opposed to "alpha taxonomy"), recognizing that boundaries between species are not always well defined. Copyright © 2015 Elsevier GmbH. All rights reserved.

Effect of Malmquist bias on correlation studies with IRAS data base

NASA Technical Reports Server (NTRS)

Verter, Frances

1993-01-01

The relationships between galaxy properties in the sample of Trinchieri et al. (1989) are reexamined with corrections for Malmquist bias. The linear correlations are tested and linear regressions are fit for log-log plots of L(FIR), L(H-alpha), and L(B) as well as ratios of these quantities. The linear correlations for Malmquist bias are corrected using the method of Verter (1988), in which each galaxy observation is weighted by the inverse of its sampling volume. The linear regressions are corrected for Malmquist bias by a new method invented here in which each galaxy observation is weighted by its sampling volume. The results of correlation and regressions among the sample are significantly changed in the anticipated sense that the corrected correlation confidences are lower and the corrected slopes of the linear regressions are lower. The elimination of Malmquist bias eliminates the nonlinear rise in luminosity that has caused some authors to hypothesize additional components of FIR emission.

Random forest models to predict aqueous solubility.

PubMed

Palmer, David S; O'Boyle, Noel M; Glen, Robert C; Mitchell, John B O

2007-01-01

Random Forest regression (RF), Partial-Least-Squares (PLS) regression, Support Vector Machines (SVM), and Artificial Neural Networks (ANN) were used to develop QSPR models for the prediction of aqueous solubility, based on experimental data for 988 organic molecules. The Random Forest regression model predicted aqueous solubility more accurately than those created by PLS, SVM, and ANN and offered methods for automatic descriptor selection, an assessment of descriptor importance, and an in-parallel measure of predictive ability, all of which serve to recommend its use. The prediction of log molar solubility for an external test set of 330 molecules that are solid at 25 degrees C gave an r2 = 0.89 and RMSE = 0.69 log S units. For a standard data set selected from the literature, the model performed well with respect to other documented methods. Finally, the diversity of the training and test sets are compared to the chemical space occupied by molecules in the MDL drug data report, on the basis of molecular descriptors selected by the regression analysis.

A Three-Parameter Generalisation of the Beta-Binomial Distribution with Applications

DTIC Science & Technology

1987-07-01

York. Rust, R.T. and Klompmaker, J.E. (1981). Improving the estimation procedure for the beta binomial t.v. exposure model. Journal of Marketing ... Research . 18, 442-448. Sabavala, D.J. and Morrison, D.G. (1977). Television show loyalty: a beta- binomial model using recall data. Journal of Advertiuing

Distribution-free Inference of Zero-inated Binomial Data for Longitudinal Studies.

PubMed

He, H; Wang, W J; Hu, J; Gallop, R; Crits-Christoph, P; Xia, Y L

2015-10-01

Count reponses with structural zeros are very common in medical and psychosocial research, especially in alcohol and HIV research, and the zero-inflated poisson (ZIP) and zero-inflated negative binomial (ZINB) models are widely used for modeling such outcomes. However, as alcohol drinking outcomes such as days of drinkings are counts within a given period, their distributions are bounded above by an upper limit (total days in the period) and thus inherently follow a binomial or zero-inflated binomial (ZIB) distribution, rather than a Poisson or zero-inflated Poisson (ZIP) distribution, in the presence of structural zeros. In this paper, we develop a new semiparametric approach for modeling zero-inflated binomial (ZIB)-like count responses for cross-sectional as well as longitudinal data. We illustrate this approach with both simulated and real study data.

Jump-and-return sandwiches: A new family of binomial-like selective inversion sequences with improved performance

NASA Astrophysics Data System (ADS)

Brenner, Tom; Chen, Johnny; Stait-Gardner, Tim; Zheng, Gang; Matsukawa, Shingo; Price, William S.

2018-03-01

A new family of binomial-like inversion sequences, named jump-and-return sandwiches (JRS), has been developed by inserting a binomial-like sequence into a standard jump-and-return sequence, discovered through use of a stochastic Genetic Algorithm optimisation. Compared to currently used binomial-like inversion sequences (e.g., 3-9-19 and W5), the new sequences afford wider inversion bands and narrower non-inversion bands with an equal number of pulses. As an example, two jump-and-return sandwich 10-pulse sequences achieved 95% inversion at offsets corresponding to 9.4% and 10.3% of the non-inversion band spacing, compared to 14.7% for the binomial-like W5 inversion sequence, i.e., they afforded non-inversion bands about two thirds the width of the W5 non-inversion band.

Writing and overwriting short-term memory

PubMed Central

Killeen, Peter R.

2008-01-01

An integrative account of short-term memory is based on data from pigeons trained to report the majority color in a sequence of lights. Performance showed strong recency effects, was invariant over changes in the interstimulus interval, and improved with increases in the intertrial interval. A compound model of binomial variance around geometrically decreasing memory described the data; a logit transformation rendered it isomorphic with other memory models. The model was generalized for variance in the parameters, where it was shown that averaging exponential and power functions from individuals or items with different decay rates generates new functions that are hyperbolic in time and in log time, respectively. The compound model provides a unified treatment of both the accrual and the dissipation of memory and is consistent with data from various experiments, including the choose-short bias in delayed recall, multielement stimuli, and Rubin and Wenzel’s (1996) meta-analyses of forgetting. PMID:11340865

Sleep duration, restfulness, and screens in the sleep environment.

PubMed

Falbe, Jennifer; Davison, Kirsten K; Franckle, Rebecca L; Ganter, Claudia; Gortmaker, Steven L; Smith, Lauren; Land, Thomas; Taveras, Elsie M

2015-02-01

Associations of inadequate sleep with numerous health outcomes among youth necessitate identifying its modifiable determinants. Television (TV) has been associated with sleep curtailment, but little is known about small screens (eg, smartphones), which can be used in bed and emit notifications. Therefore, we examined associations of different screens in sleep environments with sleep duration and perceived insufficient rest or sleep. Participants included 2048 fourth- and seventh-graders participating in the Massachusetts Childhood Obesity Research Demonstration Study in 2012 to 2013. Using linear and log binomial regression, we examined cross-sectional associations of small screens and TVs in sleep environments and screen time with weekday sleep duration and perceived insufficient rest or sleep in the past week. Children who slept near a small screen (compared with never) reported 20.6 fewer minutes of sleep (95% confidence interval [CI], -29.7 to -11.4) and had a higher prevalence of perceived insufficient rest or sleep (prevalence ratio, 1.39; 95% CI, 1.21 to 1.60). Children who slept in a room with a TV (compared with no TV) reported 18.0 fewer minutes of sleep (95% CI, -27.9 to -8.1). TV or DVD viewing and video or computer game playing were associated with both sleep outcomes (P < .01). Some associations were stronger among Hispanic, non-Hispanic black, and older children (P < .05 for heterogeneity). Sleeping near a small screen, sleeping with a TV in the room, and more screen time were associated with shorter sleep durations. Presence of a small screen, but not a TV, in the sleep environment and screen time were associated with perceived insufficient rest or sleep. These findings caution against unrestricted screen access in children's bedrooms. Copyright © 2015 by the American Academy of Pediatrics.

Genetic ancestry is associated with subclinical cardiovascular disease in African Americans and Hispanics from the Multi-Ethnic Study of Atherosclerosis (MESA)

PubMed Central

Wassel, Christina L.; Pankow, James S.; Peralta, Carmen A.; Choudhry, Shweta; Seldin, Michael F.; Arnett, Donna K.

2009-01-01

Background Differences in cardiovascular disease (CVD) burden exist among racial/ethnic groups in the United States, with African Americans having the highest prevalence. Subclinical CVD measures have also been shown to differ by race/ethnicity. In the United States, there has been significant intermixing among racial/ethnic groups creating admixed populations. Very little research exists on the relationship of genetic ancestry and subclinical CVD measures. Methods and Results These associations were investigated in 712 African-American and 705 Hispanic participants from the MESA candidate gene sub-study. Individual ancestry was estimated from 199 genetic markers using STRUCTURE. Associations of ancestry and coronary artery calcium (CAC) and common and internal carotid intima media thickness (cIMT) were evaluated using log-binomial and linear regression models. Splines indicated linear associations of ancestry with subclinical CVD measures in African-Americans, but presence of threshold effects in Hispanics. Among African Americans, each standard deviation (SD) increase in European ancestry was associated with an 8% (95% CI (1.02, 1.15), p=0.01) greater CAC prevalence. Each SD increase in European ancestry was also associated with a 2% (95% CI (−3.4%, −0.5%), p=0.008) lower common cIMT in African Americans. Among Hispanics, the highest tertile of European ancestry was associated with a 34% greater CAC prevalence, p=0.02 as compared to lowest tertile. Conclusions The linear association of ancestry and subclinical CVD suggests that genetic effects may be important in determining CAC and cIMT among African-Americans. Our results also suggest that CAC and common cIMT may be important phenotypes for further study with admixture mapping. PMID:20031644

Disparities in emergency department visits in American children with asthma: 2006-2010.

PubMed

Zhang, Qi; Lamichhane, Rajan; Diggs, Leigh Ann

2017-09-01

This article was to examine the trends in emergency department (ED) visits for asthma among American children in 2006-2010 across sociodemographic factors, parental smoking status, and children's body weight status. We analyzed 5,535 children aged 2-17 years with current asthma in the Asthma Call-Back Survey in 2006-2010. Multivariate log binomial regression was used to examine the disparities of ED visits by demographics, socioeconomic status, parental smoking status, children's body weight status, and the level of asthma control. We controlled for average state-level air pollutants. Prevalence ratios (PRs) and 95% confidence intervals (CIs) were reported. Minority children with current asthma had higher risks of ED visits compared with white children in 2009 and 2010, e.g., the PR (95% CI) for black children in 2009 was 3.64 (1.79, 7.41). Children who had current asthma and more highly educated parents experienced a higher risk of ED visits in 2007 (PRs [95% CI] = 2.15 [1.02, 4.53] and 2.97 [1.29, 6.83] for children with some college or college-graduated parents), but not significant in other years. Children with uncontrolled asthma were significantly more likely to visit the ED in 2008 (PRs [95% CI] = 2.79 [1.44, 5.41] and 6.96 [3.55, 13.64] for not-well-controlled and very poorly controlled children with asthma). Minority children with current asthma or children with uncontrolled asthma were more likely to visit EDs for asthma treatment. However, the disparities in ED visits across sociodemographics, health status, or asthma control vary in scale and significance across time. More research is needed to explain these differences.

A Randomized Controlled Trial of a Text Messaging Intervention to Promote Virologic Suppression and Retention in Care in an Urban Safety-Net HIV Clinic: The Connect4Care (C4C) Trial.

PubMed

Christopoulos, Katerina A; Riley, Elise D; Carrico, Adam W; Tulsky, Jacqueline; Moskowitz, Judith T; Dilworth, Samantha; Coffin, Lara S; Wilson, Leslie; Peretz, Jason Johnson; Hilton, Joan F

2018-02-21

Text messaging is a promising strategy to support HIV care engagement, but little is known about its efficacy in urban safety-net HIV clinic populations. We conducted a randomized controlled trial of a supportive and motivational text messaging intervention, Connect4Care (C4C), among viremic patients who had a history of poor retention or were new to clinic. Participants were randomized (stratified by new HIV diagnosis status) to receive one of the following for 12 months: 1) thrice-weekly intervention messages, plus texted primary care appointment reminders and a monthly text message requesting confirmation of study participation, or; 2) texted reminders and monthly messages alone. Viral load was assessed at 6 and 12 months. The primary outcome was virologic suppression (<200 copies/mL) at 12 months, estimated via repeated measures log-binomial regression, adjusted for new diagnosis status. The secondary outcome was retention in clinic care. Between August 2013-November 2015, 230 participants were randomized. Virologic suppression at 12 months was similar between intervention and control participants (48.8% vs. 45.8%), with negligible change from 6-month estimates, yielding RR 1.07 (95% CI: 0.82, 1.39). Suppression was higher in the newly diagnosed (78.3% vs. 45.3%). There were no intervention effects on the secondary outcome. Exploratory analyses suggested that patients with more responses to study text messages had better outcomes, regardless of arm. The C4C text messaging intervention did not significantly increase virologic suppression or retention in care. Response to text messages may be a useful way for providers to gauge risk for poor HIV outcomes. NCT01917994.

Seroprevalence of Helicobacter pylori in Hispanics living in Puerto Rico: A population-based study.

PubMed

González-Pons, María; Soto-Salgado, Marievelisse; Sevilla, Javier; Márquez-Lespier, Juan M; Morgan, Douglas; Pérez, Cynthia M; Cruz-Correa, Marcia

2018-02-01

Helicobacter pylori is an important etiologic factor for peptic ulcers and gastric cancer, one of the top ten leading causes of cancer death in Puerto Rico. However, the prevalence of H. pylori infections in this population was previously unknown. The aim of this study was to examine the seroprevalence of H. pylori and its associated risk factors in Puerto Rico. A cross-sectional study was designed using an existing population-based biorepository. Seropositivity was determined using the Premier ™ H. pylori immunoassay. Helicobacter pylori seroprevalence was estimated with 95% confidence using marginal standardization following logistic regression. To assess the risk factors associated with H. pylori seropositivity, a multivariable log-binomial model was fitted to estimate the prevalence ratio (PR) and its 95% confidence interval (95% CI). A total of 528 population-based serum samples were analyzed. The mean age of the study population was 41 ± 12 years, of whom 55.3% were females. The overall seroprevalence of H. pylori was 33.0% (95% CI = 28.3%-38.1%). Increasing age and having <12 years of education were significantly (P < .05) associated with H. pylori seropositivity in the multivariable model; however, residing in counties with low population density reached marginal significance (P = .085). We report that H. pylori infection is common among Hispanics living in Puerto Rico. The H. pylori seroprevalence observed in Puerto Rico is similar to the seroprevalence reported in the overall population of the United States. The association between H. pylori seroprevalence and the risk factors analyzed offers insight into the epidemiology of gastric cancer in Puerto Rico and warrants further investigation. © 2017 The Authors. Helicobacter Published by John Wiley & Sons Ltd.

Opting for natural birth: A survey of birth intentions among young Icelandic women.

PubMed

Swift, Emma Marie; Gottfredsdottir, Helga; Zoega, Helga; Gross, Mechthild M; Stoll, Kathrin

2017-03-01

To describe and analyse factors associated with natural birth intentions in a sample of pre-pregnant Icelandic women. An internationally validated tool was used to survey pre-pregnant women about their attitudes towards birth. The online survey was sent to all students at the University of Iceland in November 2014. Log binomial regression was used to calculate crude and adjusted relative risks (RR a ), and corresponding 95% confidence intervals (CI), for intentions of natural birth (defined as vaginal birth without epidural analgesia) by high, moderate and low childbirth fear and by high, moderate and low confidence in birth knowledge. Models were adjusted for socio-demographic and psychological factors. 410 eligible women completed the cross-sectional survey. Women with low fear of birth were more likely to have natural birth intentions when compared to women with moderate (RR a  = 2.83; 95% CI; 1.48-5.41) and high (RR a  = 4.86; 95% CI; 1.37-17.27) fear. Women with high confidence in their birth knowledge were more likely to have natural birth intentions compared to women with moderate (RR a  = 2.81; 95% CI; 1.51-5.22) and low (RR a  = 3.42; 95% CI; 1.43-8.18) confidence in their birth knowledge. Pre-pregnant women with low fear of birth and high confidence in their birth knowledge are more likely to have natural birth intentions. Addressing concerns about pain, safety, the perceived unpredictability of birth and worries about the physical impact of childbirth may strengthen natural birth intentions. Copyright © 2016 Elsevier B.V. All rights reserved.

Child and Adolescent Abuse in Relation to Obesity in Adulthood: The Black Women’s Health Study

PubMed Central

Rosenberg, Lynn; Palmer, Julie R; Boggs, Deborah A.; Wise, Lauren A.

2012-01-01

OBJECTIVE: To investigate the association of physical and sexual abuse in childhood and adolescence with risk of adult obesity among black women in the United States. METHODS: Participants were women enrolled in the Black Women’s Health Study, an ongoing prospective cohort study begun in 1995. In 2005, 33 298 participants completed a self-administered questionnaire on early life experiences of abuse. Log-binomial regression models were used to derive risk ratios (RRs) and 95% confidence intervals (CIs) for the relation of child/teenager abuse with obesity (BMI ≥30) and central adiposity (waist circumference >35 inches) reported in 2005. RESULTS: The RR for BMI ≥30, a measure of overall obesity, was 1.29 (95% CI 1.20–1.38) for the highest severity of exposure to child/teenager physical and sexual abuse relative to no abuse. After controlling for postulated intermediates, including reproductive history, diet, physical activity, depressive symptoms, and socioeconomic status, the RR was 1.14 (95% CI 1.08–1.21). The RR for waist circumference >35 inches, which measures central obesity, for severe physical and sexual abuse relative to no abuse was 1.29 (95% CI 1.19–1.38) before adjustment for intermediates and 1.18 (95% CI 1.10–1.27) after adjustment. CONCLUSIONS: Early life sexual and physical abuse was associated with an increased risk of overall and central obesity in adulthood. Although the association between abuse and obesity was explained to some extent by health behaviors, reproductive history, and mental health, these factors did not fully account for the associations. Our data suggest that early life adversity is related to adult body size and weight distribution. PMID:22753562

Birth order and paediatric allergic disease: A nationwide longitudinal survey.

PubMed

Kikkawa, T; Yorifuji, T; Fujii, Y; Yashiro, M; Okada, A; Ikeda, M; Doi, H; Tsukahara, H

2018-05-01

Environmental factors seem to be related to the incidence of allergic disease. Children with a later birth order are often exposed to environments, where pathogens and endotoxins can be found, and thus have a higher risk of developing infectious diseases. Therefore, birth order is regarded as an indicator that reflects post-natal environment. However, longitudinal studies are limited on this subject. This study sought to elucidate the relationships between birth order and allergic disease. From a nationwide longitudinal study that followed children born in 2001 (n = 47 015), we selected doctors' visits for 3 types of allergic disease-bronchial asthma, food allergy and atopic dermatitis-from infancy to 12 years of age and conducted binomial log-linear regression analysis to evaluate the associations between birth order and these diseases. We adjusted for the child and parental factors and estimated risk ratio (RR) and 95% confidence interval (CI) for each outcome. The associations between birth order and bronchial asthma were diverse; later birth order increased the risk in early childhood, but decreased the risks during school age. For example, the adjusted RR comparing third-born or higher and first-born children was 1.19 (95% CI, 1.05-1.35) between 30 and 42 months of age, but was 0.76 (95% CI, 0.65-0.89) between 10 and 11 years. Later birth order was generally protective for food allergy but increased the risk of atopic dermatitis. The influence of birth order depended on the type of allergic disease and the childhood period. Childhood is unique in terms of physical and immunological development, and the immune response to the post-natal environment in childhood appears to be heterogeneous. © 2018 John Wiley & Sons Ltd.

Global variations and time trends in the prevalence of childhood myopia, a systematic review and quantitative meta-analysis: implications for aetiology and early prevention

PubMed Central

Rudnicka, Alicja R; Kapetanakis, Venediktos V; Wathern, Andrea K; Gilmartin, Bernard; Whincup, Peter H; Cook, Derek G; Owen, Christopher G

2016-01-01

The aim of this review was to quantify the global variation in childhood myopia prevalence over time taking account of demographic and study design factors. A systematic review identified population-based surveys with estimates of childhood myopia prevalence published by February 2015. Multilevel binomial logistic regression of log odds of myopia was used to examine the association with age, gender, urban versus rural setting and survey year, among populations of different ethnic origins, adjusting for study design factors. 143 published articles (42 countries, 374 349 subjects aged 1–18 years, 74 847 myopia cases) were included. Increase in myopia prevalence with age varied by ethnicity. East Asians showed the highest prevalence, reaching 69% (95% credible intervals (CrI) 61% to 77%) at 15 years of age (86% among Singaporean-Chinese). Blacks in Africa had the lowest prevalence; 5.5% at 15 years (95% CrI 3% to 9%). Time trends in myopia prevalence over the last decade were small in whites, increased by 23% in East Asians, with a weaker increase among South Asians. Children from urban environments have 2.6 times the odds of myopia compared with those from rural environments. In whites and East Asians sex differences emerge at about 9 years of age; by late adolescence girls are twice as likely as boys to be myopic. Marked ethnic differences in age-specific prevalence of myopia exist. Rapid increases in myopia prevalence over time, particularly in East Asians, combined with a universally higher risk of myopia in urban settings, suggest that environmental factors play an important role in myopia development, which may offer scope for prevention. PMID:26802174

Anal Human Papillomavirus (HPV) Prevalences and Factors Associated with Abnormal Anal Cytology in HIV-Infected Women in an Urban Cohort from Rio de Janeiro, Brazil

PubMed Central

Luz, Paula M.; Lake, Jordan E.; Levi, José Eduardo; Coutinho, José Ricardo; de Andrade, Angela; Heinke, Thais; Derrico, Mônica; Veloso, Valdilea G.; Friedman, Ruth K.; Grinsztejn, Beatriz

2015-01-01

Abstract Identifying factors, including human papillomavirus (HPV) genotypes, associated with abnormal anal cytology in HIV-infected women have implications for anal squamous cell cancer (SCC) prevention in HIV-infected women. Anal and cervical samples were collected for cytology, and tested for high-(HR-HPV) and low-risk HPV (LR-HPV) genotypes in a cross-sectional analysis of the IPEC Women's HIV Cohort (Rio de Janeiro, Brazil). Multivariate log-binomial regression models estimated prevalence ratios for factors associated with abnormal anal cytology [≥atypical squamous cells of undetermined significance, (ASC-US)]. Characteristics of the 863 participants included: median age 42 years, 57% non-white, 79% current CD4+ T-cell count >350 cells/mm3, 53% HIV-1 viral load <50 copies/mL, median ART duration 5.8 years. Fifty-one percent of anal specimens contained ≥1 HR-HPV genotype; 31% had abnormal anal cytology [14% ASC-US, 11% low-grade squamous intra-epithelial lesion, (LSIL); 2% atypical squamous cells-cannot exclude high-grade SIL (ASC-H); 4% high-grade SIL/cancer (HSIL+)]. In multivariate analysis, cervical LSIL+, nadir CD4+ T-cell count ≤50 cells/mm3, HIV-1 viral load ≥50 copies/mL, and anal HPV 6, 11, 16, 18, 33, 45, 52, 56, and 58 were associated with ≥anal ASC-US (p<0.05). Abnormal anal cytology and HR-HPV prevalences were high. HIV-infected women with cervical LSIL+, low nadir CD4+ counts, or detectable HIV-1 viral loads should be a particular focus for enhanced anal SCC screening efforts. PMID:25361401

The use of household cleaning sprays and adult asthma: an international longitudinal study.

PubMed

Zock, Jan-Paul; Plana, Estel; Jarvis, Deborah; Antó, Josep M; Kromhout, Hans; Kennedy, Susan M; Künzli, Nino; Villani, Simona; Olivieri, Mario; Torén, Kjell; Radon, Katja; Sunyer, Jordi; Dahlman-Hoglund, Anna; Norbäck, Dan; Kogevinas, Manolis

2007-10-15

Cleaning work and professional use of certain cleaning products have been associated with asthma, but respiratory effects of nonprofessional home cleaning have rarely been studied. To investigate the risk of new-onset asthma in relation to the use of common household cleaners. Within the follow-up of the European Community Respiratory Health Survey in 10 countries, we identified 3,503 persons doing the cleaning in their homes and who were free of asthma at baseline. Frequency of use of 15 types of cleaning products was obtained in a face-to-face interview at follow-up. We studied the incidence of asthma defined as physician diagnosis and as symptoms or medication usage at follow-up. Associations between asthma and the use of cleaning products were evaluated using multivariable Cox proportional hazards or log-binomial regression analysis. The use of cleaning sprays at least weekly (42% of participants) was associated with the incidence of asthma symptoms or medication (relative risk [RR], 1.49; 95% confidence interval [CI], 1.12-1.99) and wheeze (RR, 1.39; 95% CI, 1.06-1.80). The incidence of physician-diagnosed asthma was higher among those using sprays at least 4 days per week (RR, 2.11; 95% CI, 1.15-3.89). These associations were consistent for subgroups and not modified by atopy. Dose-response relationships (P < 0.05) were apparent for the frequency of use and the number of different sprays. Risks were predominantly found for the commonly used glass-cleaning, furniture, and air-refreshing sprays. Cleaning products not applied in spray form were not associated with asthma. Frequent use of common household cleaning sprays may be an important risk factor for adult asthma.

The Use of Household Cleaning Sprays and Adult Asthma

PubMed Central

Zock, Jan-Paul; Plana, Estel; Jarvis, Deborah; Antó, Josep M.; Kromhout, Hans; Kennedy, Susan M.; Künzli, Nino; Villani, Simona; Olivieri, Mario; Torén, Kjell; Radon, Katja; Sunyer, Jordi; Dahlman-Hoglund, Anna; Norbäck, Dan; Kogevinas, Manolis

2007-01-01

Rationale: Cleaning work and professional use of certain cleaning products have been associated with asthma, but respiratory effects of nonprofessional home cleaning have rarely been studied. Objectives: To investigate the risk of new-onset asthma in relation to the use of common household cleaners. Methods: Within the follow-up of the European Community Respiratory Health Survey in 10 countries, we identified 3,503 persons doing the cleaning in their homes and who were free of asthma at baseline. Frequency of use of 15 types of cleaning products was obtained in a face-to-face interview at follow-up. We studied the incidence of asthma defined as physician diagnosis and as symptoms or medication usage at follow-up. Associations between asthma and the use of cleaning products were evaluated using multivariable Cox proportional hazards or log-binomial regression analysis. Measurements and Main Results: The use of cleaning sprays at least weekly (42% of participants) was associated with the incidence of asthma symptoms or medication (relative risk [RR], 1.49; 95% confidence interval [CI], 1.12−1.99) and wheeze (RR, 1.39; 95% CI, 1.06−1.80). The incidence of physician-diagnosed asthma was higher among those using sprays at least 4 days per week (RR, 2.11; 95% CI, 1.15−3.89). These associations were consistent for subgroups and not modified by atopy. Dose–response relationships (P < 0.05) were apparent for the frequency of use and the number of different sprays. Risks were predominantly found for the commonly used glass-cleaning, furniture, and air-refreshing sprays. Cleaning products not applied in spray form were not associated with asthma. Conclusions: Frequent use of common household cleaning sprays may be an important risk factor for adult asthma. PMID:17585104

Prevalence and sociodemographic characteristics of women with induced abortion in a population sample of São Paulo, Brazil.

PubMed

Souza, Milena Goulart; Fusco, Carmen L B; Andreoni, Solange A; de Souza e Silva, Rebeca

2014-01-01

This study aims at estimating the prevalence of women with induced abortion among women of childbearing age (15-49 years) who had any previous pregnancy, in the city of Sao Paulo, Brazil, in the last quarter of 2008, and identifying the Sociodemographic Characteristics (SC) associated with it. A cross-sectional survey was carried out. The dependent variable was dichotomized as: no abortion and induced abortion. The independent variables were: age, paid work/activity, familial monthly income, schooling, marital status, contraceptive use and number of live births. Statistical analysis was performed using log-binomial regression models with approximation of Poisson to estimate the Prevalance Ratios (PR). Of all women with any previous pregnancy (n = 683), 4.5% (n = 31) reported induced abortion. The final multivariate model showed that having now between 40 and 44 years (PR = 2.76, p = 0.0043), being single (PR = 2.79, p = 0.0159), having 5 or more live births (PR = 3.97, p = 0.0013), current oral contraception or IUD use (PR = 2.70, p = 0.454) and using a "non effective" (or of low efficacy) contraceptive method (PR = 4.18, p = 0.0009) were sociodemographic characteristics associated with induced abortion in this population. Induced abortion seems to be used to limit fertility, more precisely after having reached the desired number of children. The inadequate use or non-use of effective contraceptive methods, and / or the use of contraceptives " non effective", exposed also the women to the risk of unintended pregnancies and, therefore, induced abortions. In addition, when faced with a pregnancy, single women were more likely to have an abortion than married women.

An analysis of blood donation barriers experienced by North American and Caribbean university students in Grenada, West Indies.

PubMed

Dean, Benjamin W; Hewitt, Sarah N; Begos, Morgan C; Gomez, Angela; Messam, Locksley L McV

2018-02-01

To estimate the associations of nationality, university program, donation history and gender, with blood donation barriers experienced by non-donating students on the day of a campus blood drive. This project focused particularly on nationality and the effect of the different blood donation cultures in the students' countries of origin. A retrospective cohort study of 398 North American and Caribbean university students was conducted at St. George's University, Grenada, in 2010. Data were collected from non-donating students on campus while a blood drive was taking place. Log-binomial regression was used to estimate associations between the exposures of interest and donation barriers experienced by the students. North American (voluntary blood donation culture) students were more likely than Caribbean (replacement blood donation culture) students to experience "Lack of Time" (relative risk (RR) = 1.57; 95% confidence interval (CI): 1.19-2.07) and "Lack of Eligibility" (RR = 1.55; 95% CI: 1.08-2.22) as barriers to donation. Conversely, Caribbean students were a third as likely to state "Lack of Incentive" (RR = 0.32; 95% CI: 0.20-0.50), "Fear of Infection" (RR = 0.35; 95% CI: 0.21-0.58), and "Fear of Needles" (RR = 0.32; 95% CI: 0.21-0.48) were barriers than North American students. University students from voluntary blood donation cultures are likely to experience different barriers to donation than those from replacement cultures. Knowledge of barriers that students from contrasting blood donation systems face provides valuable information for blood drive promotion in university student populations that contain multiple nationalities. Copyright © 2017 Elsevier Ltd. All rights reserved.

Public support for intergenerational oocyte donation in the United States.

PubMed

Bortoletto, Pietro; Farland, Leslie V; Ginsburg, Elizabeth S; Goldman, Randi H

2018-02-01

To determine whether the general public supports intergenerational oocyte donation. Cross-sectional study. Not applicable. A nationally representative sample based on age distribution of United States residents. Not applicable. Characteristics of respondents who supported (strongly agree and agree) various oocyte donation practices were compared with participants who did not support them (disagree and strongly disagree) using log binomial regression to calculate risk ratios (RRs) and 95% confidence intervals of support (95% CIs). Models were adjusted for age, gender, and religion to yield adjusted risk ratios (aRR). A total of 1,915 people responded to the Web-based survey; 53% were female, and 24% were racial/ethnic minorities. Eighty-five percent had prior knowledge of oocyte donation, and 74% felt that a woman should be able to donate oocytes to a family member. The desire to help a family member was the most commonly perceived motivation for donors (79%). Christian-Catholics compared with Christian-non-Catholics (aRR 0.91, 95% CI 0.86-0.98), African Americans compared with non-Hispanic Caucasians (aRR 0.86, 95% CI 0.76-0.97), and Republicans compared with Democrats (RR 0.93, 95% CI 0.88-0.98) were less likely to support intergenerational oocyte donation. Respondents with three or more biological children (RR 1.06, 95% CI 1.00-1.11) compared with those with no children were less likely to support this practice. Eight percent of participants disapproved of donation to any family member. The most common reason for disapproval was the potential negative impact on the child (53%). A majority of Americans support the practice of intergenerational oocyte donation; however, support varies according to demographic characteristics. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Investigation of an Outbreak of Variant Influenza A(H3N2) Virus Infection Associated With an Agricultural Fair-Ohio, August 2012.

PubMed

Greenbaum, Adena; Quinn, Celia; Bailer, Jennifer; Su, Su; Havers, Fiona; Durand, Lizette O; Jiang, Victoria; Page, Shannon; Budd, Jeremy; Shaw, Michael; Biggerstaff, Matthew; de Fijter, Sietske; Smith, Kathleen; Reed, Carrie; Epperson, Scott; Brammer, Lynnette; Feltz, Dave; Sohner, Kevin; Ford, Jared; Jain, Seema; Gargiullo, Paul; Weiss, Edward; Burg, Pat; DiOrio, Mary; Fowler, Brian; Finelli, Lyn; Jhung, Michael A

2015-11-15

In 2012, one third of cases in a multistate outbreak of variant influenza A(H3N2) virus ([H3N2]v) infection occurred in Ohio. We conducted an investigation of (H3N2)v cases associated with agricultural Fair A in Ohio. We surveyed Fair A swine exhibitors and their household members. Confirmed cases had influenza-like illness (ILI) and a positive laboratory test for (H3N2)v, and probable cases had ILI. We calculated attack rates. We determined risk factors for infection, using multivariable log-binomial regression. We identified 20 confirmed and 94 probable cases associated with Fair A. Among 114 cases, the median age was 10 years, there were no hospitalizations or deaths, and 82% had swine exposure. In the exhibitor household cohort of 359 persons (83 households), we identified 6 confirmed cases (2%) and 40 probable cases (11%). An age of <10 years was a significant risk factor (P < .01) for illness. One instance of likely human-to-human transmission was identified. In this (H3N2)v outbreak, no evidence of sustained human-to-human (H3N2)v transmission was found. Our risk factor analysis contributed to the development of the recommendation that people at increased risk of influenza-associated complications, including children aged <5 years, avoid swine barns at fairs during the 2012 fair season. Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Eggs in Early Complementary Feeding and Child Growth: A Randomized Controlled Trial.

PubMed

Iannotti, Lora L; Lutter, Chessa K; Stewart, Christine P; Gallegos Riofrío, Carlos Andres; Malo, Carla; Reinhart, Gregory; Palacios, Ana; Karp, Celia; Chapnick, Melissa; Cox, Katherine; Waters, William F

2017-07-01

Eggs are a good source of nutrients for growth and development. We hypothesized that introducing eggs early during complementary feeding would improve child nutrition. A randomized controlled trial was conducted in Cotopaxi Province, Ecuador, from March to December 2015. Children ages 6 to 9 months were randomly assigned to treatment (1 egg per day for 6 months [ n = 83]) and control (no intervention [ n = 80]) groups. Both arms received social marketing messages to encourage participation in the Lulun Project ( lulun meaning "egg" in Kichwa). All households were visited once per week to monitor morbidity symptoms, distribute eggs, and monitor egg intakes (for egg group only). Baseline and end point outcome measures included anthropometry, dietary intake frequencies, and morbidity symptoms. Mothers or other caregivers reported no allergic reactions to the eggs. Generalized linear regression modeling showed the egg intervention increased length-for-age z score by 0.63 (95% confidence interval [CI], 0.38-0.88) and weight-for-age z score by 0.61 (95% CI, 0.45-0.77). Log-binomial models with robust Poisson indicated a reduced prevalence of stunting by 47% (prevalence ratio [PR], 0.53; 95% CI, 0.37-0.77) and underweight by 74% (PR, 0.26; 95% CI, 0.10-0.70). Children in the treatment group had higher dietary intakes of eggs (PR, 1.57; 95% CI, 1.28-1.92) and reduced intake of sugar-sweetened foods (PR, 0.71; 95% CI, 0.51-0.97) compared with control. The findings supported our hypothesis that early introduction of eggs significantly improved growth in young children. Generally accessible to vulnerable groups, eggs have the potential to contribute to global targets to reduce stunting. Copyright © 2017 by the American Academy of Pediatrics.

Impact of Childhood Nutritional Status on Pathogen Prevalence and Severity of Acute Diarrhea

PubMed Central

Tickell, Kirkby D.; Pavlinac, Patricia B.; John-Stewart, Grace C.; Denno, Donna M.; Richardson, Barbra A.; Naulikha, Jaqueline M.; Kirera, Ronald K.; Swierczewski, Brett E.; Singa, Benson O.; Walson, Judd L.

2017-01-01

Abstract. Children with acute and chronic malnutrition are at increased risk of morbidity and mortality following a diarrheal episode. To compare diarrheal disease severity and pathogen prevalence among children with and without acute and chronic malnutrition, we conducted a cross-sectional study of human immunodeficiency virus-uninfected Kenyan children aged 6–59 months, who presented with acute diarrhea. Children underwent clinical and anthropometric assessments and provided stool for bacterial and protozoal pathogen detection. Clinical and microbiological features were compared using log binomial regression among children with and without wasting (mid-upper arm circumference ≤ 125 mm) or stunting (height-for-age z score ≤ −2). Among 1,363 children, 7.0% were wasted and 16.9% were stunted. After adjustment for potential confounders, children with wasting were more likely than nonwasted children to present with at least one Integrated Management of Childhood Illness danger sign (adjusted prevalence ratio [aPR]: 1.3, 95% confidence interval [CI]: 1.0 to 1.5, P = 0.05), severe dehydration (aPR: 2.4, 95% CI: 1.5 to 3.8, P < 0.01), and enteroaggregative Escherichia coli recovered from their stool (aPR: 1.8, 1.1–2.8, P = 0.02). There were no differences in the prevalence of other pathogens by wasting status after confounder adjustment. Stunting was not associated with clinical severity or the presence of specific pathogens. Wasted children with diarrhea presented with more severe disease than children without malnutrition which may be explained by a delay in care-seeking or diminished immune response to infection. Combating social determinants and host risk factors associated with severe disease, rather than specific pathogens, may reduce the disparities in poor diarrhea-associated outcomes experienced by malnourished children. PMID:29140236

Physical and psychosocial ergonomic risk factors for low back pain in automobile manufacturing workers.

PubMed

Vandergrift, Jonathan L; Gold, Judith E; Hanlon, Alexandra; Punnett, Laura

2012-01-01

To examine the association between ergonomic physical and psychosocial exposures and the risk of prevalent and incident low back pain (LBP) in a longitudinal cohort of automobile manufacturing workers. Ergonomic exposure intensity and LBP presence were determined through questionnaires at baseline (n=1181) and to workers in the same job 1 year later (n=505). Models were constructed using log-binomial regression with special attention to interactions between ergonomic exposures. Awkward back posture (prevalence ratio (PR) 1.12, 95% CI 1.07 to 1.17), hand force (PR 1.06, 95% CI 1.02 to 1.10), physical effort (PR 1.10, 95% CI 1.04 to 1.16) and whole body vibration (PR 1.04, 95% CI 1.01 to 1.08) were each associated cross-sectionally with LBP. Awkward back posture (RR 1.13, 95% CI 0.98 to 1.31) and hand force (RR 1.07, 95% CI 0.93 to 1.22) also predicted incident LBP, although estimates were statistically less precise. Neither job control, psychological demands, nor job strain was independently related to risk of incident LBP. Among participants reporting high physical ergonomic exposures and moderate to high job control, increasing job demands was associated with a reduced LBP risk (RR 0.72, 95% CI 0.52 to 1.00). Among participants reporting high physical exposures and low job control, psychological demands was associated with an increased LBP risk (RR 1.30, 95% CI 1.02 to 1.66). Psychosocial workplace interventions for LBP should prioritise jobs in which there are high physical ergonomic exposures. Future studies of LBP should examine the interactions between physical ergonomic risk factors.

Chronic exposure to adverse psychosocial work factors and high psychological distress among white-collar workers: A 5-year prospective study.

PubMed

Ndjaboue, Ruth; Brisson, Chantal; Talbot, Denis; Vézina, Michel

2017-03-01

Prospective studies which evaluated whether the effects of chronic exposure to psychosocial work factors on mental health persisted over time are scarce. For the first time, this study evaluated: 1) the effect of chronic exposure to effort-reward imbalance over 5years on the prevalence of high psychological distress among men and women, and 2) the persistence of this effect over time. Overall, 1747 white-collar workers from three public organizations participated in a prospective study. Psychological distress and effort-reward imbalance were measured using validated questionnaires at baseline, and at 3- and 5-year follow-ups. Prevalence ratios (PRs) of high psychological distress were estimated using log-binomial regression according to baseline and repeated exposure. Compared to unexposed workers, those with repeated exposure to effort-reward imbalance had a higher prevalence of high psychological distress. Workers exposed only at some time-points also had a higher prevalence. The deleterious effect of repeated exposure observed at the 3-year follow-up persisted at the 5-year follow-up among women (PR=2.48 95% confidence interval (CI) 1.97-3.11) and men (PR=1.91 95% CI 1.20-3.04). These effects were greater than those found using a single baseline measurement. The current study supported a deleterious effect of repeated exposure to effort-reward imbalance on psychological distress, and a lack of adaptation to these effects over time among men and women. Since psychological distress may later lead to severe mental problems, current results highlight the need to consider exposure to these adverse work factors in primary and secondary preventions aimed at reducing mental health problems at work. Copyright © 2017 Elsevier Inc. All rights reserved.

Private equity ownership and nursing home financial performance.

PubMed

Pradhan, Rohit; Weech-Maldonado, Robert; Harman, Jeffrey S; Laberge, Alex; Hyer, Kathryn

2013-01-01

Private equity has acquired multiple large nursing home chains within the last few years; by 2009, it owned nearly 1,900 nursing homes. Private equity is said to improve the financial performance of acquired facilities. However, no study has yet examined the financial performance of private equity nursing homes, ergo this study. The primary purpose of this study is to understand the financial performance of private equity nursing homes and how it compares with other investor-owned facilities. It also seeks to understand the approach favored by private equity to improve financial performance-for instance, whether they prefer to cut costs or maximize revenues or follow a mixed approach. Secondary data from Medicare cost reports, the Online Survey, Certification and Reporting, Area Resource File, and Brown University's Long-term Care Focus data set are combined to construct a longitudinal data set for the study period 2000-2007. The final sample is 2,822 observations after eliminating all not-for-profit, independent, and hospital-based facilities. Dependent financial variables consist of operating revenues and costs, operating and total margins, payer mix (census Medicare, census Medicaid, census other), and acuity index. Independent variables primarily reflect private equity ownership. The study was analyzed using ordinary least squares, gamma distribution with log link, logit with binomial family link, and logistic regression. Private equity nursing homes have higher operating margin as well as total margin; they also report higher operating revenues and costs. No significant differences in payer mix are noted. Results suggest that private equity delivers superior financial performance compared with other investor-owned nursing homes. However, causes for concern remain particularly with the long-term financial sustainability of these facilities.

Pregnant Women with Inflammatory Bowel Disease are at Increased Risk of Vitamin D Insufficiency: A Cross-Sectional Study.

PubMed

Lee, Sangmin; Metcalfe, Amy; Raman, Maitreyi; Leung, Yvette; Aghajafari, Fariba; Letourneau, Nicole; Panaccione, Remo; Kaplan, Gilaad G; Seow, Cynthia H

2018-03-13

Vitamin D insufficiency is prevalent in individuals with inflammatory bowel disease, as well as in pregnant women; however, the prevalence of vitamin D insufficiency in pregnant women with IBD is unknown. This study assessed the prevalence of vitamin D insufficiency in pregnant women with IBD and the adequacy of recommended supplementation. A cross-sectional study was conducted in pregnant women with inflammatory bowel disease (Crohn's disease=61, ulcerative colitis=41) and without inflammatory bowel disease (n=574). Chi-square tests and log binomial regression were used to examine the prevalence of vitamin D insufficiency. Covariates included ethnicity and season. Adequacy of vitamin D supplementation during pregnancy was also assessed. The prevalence of vitamin D insufficiency (25-OHD ≤75 nmol/L) in those with Crohn's disease was 50.8% (95% CI: 38.4%-63.2%) and 60.9% (95% CI: 45.3%-74.7%) with ulcerative colitis compared to 17.4% (95% CI: 14.6%-20.8%) without inflammatory bowel disease. Women with inflammatory bowel disease were more likely to be vitamin D insufficient after adjusting for ethnicity and season (Crohn's disease - adjusted relative risk [aRR]=2.98, 95% CI: 2.19-4.04; ulcerative colitis - aRR=3.61, 95% CI: 2.65-4.93). Despite vitamin D supplementation, 32.3% (95% CI: 17.8%-51.2%) with Crohn's disease, 58.3% (95% CI: 37.1%-76.9%) with ulcerative colitis and 10.8% (95% CI: 6.9%-16.6%) without inflammatory bowel disease were still vitamin D insufficient. Pregnant women with inflammatory bowel disease are at increased risk of vitamin D insufficiency compared with those without inflammatory bowel disease. The current guidelines for vitamin D supplementation may be inadequate for pregnant women with inflammatory bowel disease.

RSV associated hospitalizations in children in Karachi, Pakistan: Implications for vaccine prevention strategies.

PubMed

Ali, Asad; Yousafzai, Mohammad Tahir; Waris, Rabbia; Jafri, Fatima; Aziz, Fatima; Abbasi, Imran Naeem; Zaidi, Anita

2017-07-01

Major progress is being made in vaccines against Respiratory Syncytial Virus (RSV), with multiple vaccine candidates currently in the clinical phase of development. Making an investment case for public sector financing of RSV vaccine will require estimation of burden, cost-effectiveness, and impact. The aim of this study is to determine the proportion, age distribution and clinical spectrum of RSV associated hospitalizations in children in Karachi, Pakistan. A three years prospective study was conducted at the Aga Khan University Hospital in Karachi, a city of 20 million in south Pakistan, from August 2009 to June 2012. Children less than five years old admitted with acute respiratory infections (ARI) were enrolled. Throat swabs were collected and tested for RSV using real-time PCR. Multivariable log binomial regression analysis was performed to identify the associated factors of RSV infection. Out of 1150 children enrolled, RSV was detected among 223 (19%). Highest rate of RSV detection was in young infants less than 3 months of age (48/168, 29%), which accounted for 22% of all RSV detected. Most common diagnosis in RSV positive infants (<12 months of age) was bronchiolitis followed by pneumonia, while in older children between the ages of one and 5 years of age, pneumonia and asthma were the most common diagnosis. Although identified year-round, RSV was most prevalent from August to October with peak in September, coinciding with the rainy season. This study identified RSV to be independently associated with younger age (P = 0.036), rainy season (P < 0.001), post-tussive emesis (P = 0.008), intubation (P = 0.003), and discharge diagnosis of bronchiolitis (P = 0.004). Vaccines against RSV that target this age group are likely to yield remarkable benefit. © 2017 Wiley Periodicals, Inc.

Heavy metal and trace element concentrations in blood and follicular fluid affect ART outcome.

PubMed

Tolunay, Harun Egemen; Şükür, Yavuz Emre; Ozkavukcu, Sinan; Seval, Mehmet Murat; Ateş, Can; Türksoy, Vugar Ali; Ecemiş, Tolga; Atabekoğlu, Cem Somer; Özmen, Batuhan; Berker, Bülent; Sönmezer, Murat

2016-03-01

To assess the effects of heavy metal and trace element concentrations in blood and follicular fluid on assisted reproductive technology cycle outcome. A prospective study was conducted between January 2012 and July 2012 in a university hospital infertility clinic. One hundred and one patients with unexplained infertility who underwent intracytoplasmic sperm injection using GnRH-antagonist protocol were recruited. Concentrations of four toxic metals (Cd, Pb, Hg, As) and three trace elements (Cu, Zn, Fe) were measured both in blood and follicular fluid specimens. Patients were evaluated in two groups; the study group consisted of patients with ongoing pregnancy (n=20) and the reference group consisted of patients experienced assisted reproductive technology failure, miscarriage or biochemical pregnancy (n=81). Demographics and cycle parameters were comparable between the groups except for median number of day 3 Grade A embryos. Statistically significant negative correlations were found between blood Pb levels and number of MII oocytes, implantation, clinical pregnancy and ongoing pregnancy rates. Results of the log binomial regression revealed 2.2% lower risk for ongoing pregnancy for each 1μg/dL higher blood Pb concentration while holding the other variables in the model constant (RR 0.978; 95% CI 0.956-0.998; P=.041). Also, the results revealed 71.9% lower risk for ongoing pregnancy for each 1μg/dL higher follicular fluid Cu concentration while holding the other variables in the model constant (RR 0.288; 95% CI 0.085-0.92; P=.039). Blood concentrations of Pb and follicular fluid concentrations of Cu seem to have significant impacts on assisted reproductive technology cycle outcome. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Obesity as a Determinant of Staphylococcus aureus Colonization Among Inmates in Maximum-Security Prisons in New York State

PubMed Central

Befus, Montina; Lowy, Franklin D.; Miko, Benjamin A.; Mukherjee, Dhritiman V.; Herzig, Carolyn T. A.; Larson, Elaine L.

2015-01-01

Obesity increases a person's susceptibility to a variety of infections, including Staphylococcus aureus infections, which is an important cause of morbidity in correctional settings. Using a cross-sectional design, we assessed the association between obesity and S. aureus colonization, a risk factor for subsequent infection, in New York State maximum-security prisons (2011–2013). Anterior nares and oropharyngeal cultures were collected. Structured interviews and medical records were used to collect demographic, behavioral, and medical data. Body mass index (BMI; weight (kg)/height (m2)) was categorized as 18.5–24.9, 25–29.9, 30–34.9, or ≥35. The association between BMI and S. aureus colonization was assessed using log-binomial regression. Thirty-eight percent of 638 female inmates and 26% of 794 male inmates had a BMI of 30 or higher. More than 40% of inmates were colonized. Female inmates with a BMI of 25–29.9 (prevalence ratio (PR) = 1.37, 95% confidence interval (CI): 1.06, 1.76), 30–34.9 (PR = 1.52, 95% CI: 1.17, 1.98), or ≥35 (PR = 1.49, 95% CI: 1.13, 1.96) had a higher likelihood of colonization than did those with a BMI of 18.5–24.9 after we controlled for age, educational level, smoking status, diabetes status, and presence of human immunodeficiency virus. Colonization was higher among male inmates with a BMI of 30–34.9 (PR = 1.27, 95% CI: 1.01, 1.61). Our findings demonstrate an association between BMI and S. aureus colonization among female prisoners. Potential contributory biologic and behavioral factors should be explored. PMID:26292691

Maternal use of folic acid supplements and infant risk of neural tube defects in Norway 1999-2013.

PubMed

Gildestad, Trude; Øyen, Nina; Klungsøyr, Kari; Nilsen, Roy Miodini; Daltveit, Anne Kjersti; Vollset, Stein Emil

2016-08-01

Like most European countries, Norway has refrained from mandatory food fortification with folic acid to reduce the number of neural tube defects. We explored the role of folic acid and multivitamin supplements in the prevention of neural tube defects among newborn infants. We used data from the Medical Birth Registry of Norway, 1999-2013. A total of 528,220 women had 880,568 pregnancies resulting in 896,674 live- and stillborn infants, of whom 270 had neural tube defects. Relative risks were estimated with log-binomial regression. From 1999 to 2013, intake of folic acid supplements increased from 4.8% to 27.4%. Vitamin supplement use was more frequent in older, married or cohabiting women and those with lower parity, as well as women who did not smoke during pregnancy. The overall adjusted relative risk of infant neural tube defects associated with maternal vitamin intake before pregnancy relative to no intake was 0.76 (95% confidence interval: 0.53-1.10). When we divided our study period in two (1999-2005 and 2006-2013), we found a significantly reduced risk of neural tube defects overall by vitamin use in the second time period, but not in the first: adjusted relative risk 0.54 (95% confidence interval: 0.31-0.91) and 1.02 (95% confidence interval: 0.63-1.65), respectively. OVER THE FULL STUDY PERIOD, WE FOUND NO STATISTICALLY SIGNIFICANT ASSOCIATION BETWEEN VITAMIN USE AND NEURAL TUBE DEFECTS OVERALL HOWEVER, VITAMIN USE WAS ASSOCIATED WITH A SIGNIFICANTLY LOWER RISK OF NEURAL TUBE DEFECTS IN THE SECOND HALF OF THE STUDY PERIOD, 2006-2013. © 2016 the Nordic Societies of Public Health.

Leprosy in Brazil and its association with characteristics of municipalities: ecological study, 2009-2011.

PubMed

Freitas, Lúcia R S; Duarte, Elisabeth C; Garcia, Leila P

2014-10-01

To analyse the ecological association between the demographic and socio-economic characteristics of the Brazilian municipalities and average leprosy incidence rate in the period 2009-2011. An ecological study taking the Brazilian municipalities as its units of analysis. The local empirical Bayes estimation method was used to obtain smoothed incidence rates (SIR) for leprosy. The mean, median, first quartile (Q1) and third quartile (Q3) of the SIR were calculated per 100 000 inhabitants. Hierarchical log-linear negative binomial regression models were used to estimate the incidence rate ratios (IRR). In the period 2009-2011, the average SIR of leprosy in Brazil was 20.2 per 100 000 inhabitants, and the median incidence rate among municipalities was 9.1 per 100 000 inhabitants. Significantly higher adjusted IRR were identified for large municipalities (IRR = 1.67) compared to small municipalities, as well as in municipalities with higher illiteracy rates (IRR = 2.15), more urbanised municipalities (IRR = 1.53), those with greater social inequality as per the Gini index (IRR = 1.26), high percentage of households with inadequate sanitation (IRR = 1.63), higher average number of people per room (IRR = 1.41), high proportions of Family Health Programme coverage (IRR = 1.29), high percentage of household contacts investigated (IRR = 2.30) and those with percentage of cases with grade 2 disability considered to be the medium (IRR = 1.26). In this study, SIR was significantly associated with municipalities with low socio-economic status. Disease control activities need to be focused on these municipalities, and investments need to be made in improving the population's living conditions. © 2014 John Wiley & Sons Ltd.

Reduced vaginal elasticity, reduced lubrication, and deep and superficial dyspareunia in irradiated gynecological cancer survivors.

PubMed

Stinesen Kollberg, Karin; Waldenström, Ann-Charlotte; Bergmark, Karin; Dunberger, Gail; Rossander, Anna; Wilderäng, Ulrica; Åvall-Lundqvist, Elisabeth; Steineck, Gunnar

2015-05-01

The purpose of this study was to examine whether or not vaginal elasticity or lack of lubrication is associated with deep or superficial dyspareunia. We investigated gynecological cancer survivors treated with radiation therapy. In a population-based study with 616 women answering a questionnaire (participation rate 78%) and who were treated with radiotherapy for gynecological cancer, we analyzed information from 243 women (39%) who reported that they had had intercourse during the previous six months. Analyses included log-binomial regression (relative risks) and multiple imputations by chained equations in combination with Bayesian Model Averaging, yielding a posterior probability value. Age range of this cancer recurrent-free group of women was 29-80. Dyspareunia affected 164 of 243 of the women (67%). One hundred thirty-four women (55%) reported superficial pain, 97 women (40%) reported deep pain, and 87 women (36%) reported both types of dyspareunia. The relative risk (RR) of deep dyspareunia was 1.87 (CI 1.41-2.49) with impaired vaginal elasticity compared to normal vaginal elasticity. Age and lower abdominal swelling were separate risk factors for deep dyspareunia. However, effects remain after adjusting for these factors. The relative risk of deep dyspareunia was almost twice as high with impaired vaginal elasticity compared to normal vaginal elasticity. If we wish to treat or even prevent deep dyspareunia in women with gynecological cancer, we may use our knowledge of the pathophysiology of deep dyspareunia and increasingly provide dilators together with instructions on how to use them for stretching exercises in order to retain vaginal elasticity. Results highlight the need for studies with more precise questions distinguishing superficial from deep dyspareunia so that in the future we may be able to primarily try to avoid reduced vaginal elasticity and secondarily reduce the symptoms.

Understanding Predictors of Early Antenatal Care Initiation in Relationship to Timing of HIV Diagnosis in South Africa.

PubMed

Nattey, Cornelius; Jinga, Nelly; Mongwenyana, Constance; Mokhele, Idah; Mohomi, Given; Fox, Matthew P; Onoya, Dorina

2018-06-01

Effective prevention of mother-to-child transmission benefits from early presentation to antenatal care (ANC). It is, however, unclear whether a previous HIV diagnosis results in earlier initiation of ANC. We estimated the probability of early ANC initiation among women with a previous HIV-positive diagnosis compared to those who first tested for HIV during ANC and explored determinants of early ANC among HIV-positive women. We conducted an analysis of a cross-sectional survey among 411 HIV-positive adult (>18 years) women who gave birth at midwife obstetrics units in Gauteng between October 2016 and May 2017. Predictors of early ANC (defined as initiating ANC before or at 14 weeks of gestation) were assessed by multivariate log-binomial regression model. Overall, 51% (210) were diagnosed during pregnancy with 89% (188) initiating antiretroviral therapy on the same day of diagnosis. There was no meaningful difference in the timing of ANC initiation between women with previous HIV diagnosis [adjusted risk ratio (aRR) = 1.2; 95% confidence interval (95% CI): 0.9-1.7] compared with those diagnosed during pregnancy. Early ANC was predicted by planned pregnancy [aRR = 1.3; 95% CI: 1.1-1.7], parity (>2 children) [aRR = 0.6; 95% CI: 0.2-0.9] compared to not having a child, and tuberculosis diagnosis [aRR = 2.9; 95% CI: 1.4-6.1]. Our results suggest the need for a targeted intervention among HIV-positive women by improving the quality, content and outreach of ANC services to enhance early ANC uptake, and minimize mother-to-child transmission risk.

Motorcycle helmet effectiveness in reducing head, face and brain injuries by state and helmet law.

PubMed

Olsen, Cody S; Thomas, Andrea M; Singleton, Michael; Gaichas, Anna M; Smith, Tracy J; Smith, Gary A; Peng, Justin; Bauer, Michael J; Qu, Ming; Yeager, Denise; Kerns, Timothy; Burch, Cynthia; Cook, Lawrence J

2016-12-01

Despite evidence that motorcycle helmets reduce morbidity and mortality, helmet laws and rates of helmet use vary by state in the U.S. We pooled data from eleven states: five with universal laws requiring all motorcyclists to wear a helmet, and six with partial laws requiring only a subset of motorcyclists to wear a helmet. Data were combined in the Crash Outcome Data Evaluation System's General Use Model and included motorcycle crash records probabilistically linked to emergency department and inpatient discharges for years 2005-2008. Medical outcomes were compared between partial and universal helmet law settings. We estimated adjusted relative risks (RR) and 95 % confidence intervals (CIs) for head, facial, traumatic brain, and moderate to severe head/facial injuries associated with helmet use within each helmet law setting using generalized log-binomial regression. Reported helmet use was higher in universal law states (88 % vs. 42 %). Median charges, adjusted for inflation and differences in state-incomes, were higher in partial law states (emergency department $1987 vs. $1443; inpatient $31,506 vs. $25,949). Injuries to the head and face, including traumatic brain injuries, were more common in partial law states. Effectiveness estimates of helmet use were higher in partial law states (adjusted-RR (CI) of head injury: 2.1 (1.9-2.2) partial law single vehicle; 1.4 (1.2, 1.6) universal law single vehicle; 1.8 (1.6-2.0) partial law multi-vehicle; 1.2 (1.1-1.4) universal law multi-vehicle). Medical charges and rates of head, facial, and brain injuries among motorcyclists were lower in universal law states. Helmets were effective in reducing injury in both helmet law settings; lower effectiveness estimates were observed in universal law states.

Motorcycle helmet effectiveness in reducing head, face and brain injuries by state and helmet law.

PubMed

Olsen, Cody S; Thomas, Andrea M; Singleton, Michael; Gaichas, Anna M; Smith, Tracy J; Smith, Gary A; Peng, Justin; Bauer, Michael J; Qu, Ming; Yeager, Denise; Kerns, Timothy; Burch, Cynthia; Cook, Lawrence J

Despite evidence that motorcycle helmets reduce morbidity and mortality, helmet laws and rates of helmet use vary by state in the U.S. We pooled data from eleven states: five with universal laws requiring all motorcyclists to wear a helmet, and six with partial laws requiring only a subset of motorcyclists to wear a helmet. Data were combined in the Crash Outcome Data Evaluation System's General Use Model and included motorcycle crash records probabilistically linked to emergency department and inpatient discharges for years 2005-2008. Medical outcomes were compared between partial and universal helmet law settings. We estimated adjusted relative risks (RR) and 95 % confidence intervals (CIs) for head, facial, traumatic brain, and moderate to severe head/facial injuries associated with helmet use within each helmet law setting using generalized log-binomial regression. Reported helmet use was higher in universal law states (88 % vs. 42 %). Median charges, adjusted for inflation and differences in state-incomes, were higher in partial law states (emergency department $1987 vs. $1443; inpatient $31,506 vs. $25,949). Injuries to the head and face, including traumatic brain injuries, were more common in partial law states. Effectiveness estimates of helmet use were higher in partial law states (adjusted-RR (CI) of head injury: 2.1 (1.9-2.2) partial law single vehicle; 1.4 (1.2, 1.6) universal law single vehicle; 1.8 (1.6-2.0) partial law multi-vehicle; 1.2 (1.1-1.4) universal law multi-vehicle). Medical charges and rates of head, facial, and brain injuries among motorcyclists were lower in universal law states. Helmets were effective in reducing injury in both helmet law settings; lower effectiveness estimates were observed in universal law states.

Tetanus, diphtheria, and acellular pertussis vaccination during pregnancy and reduced risk of infant acute respiratory infections.

PubMed

Khodr, Zeina G; Bukowinski, Anna T; Gumbs, Gia R; Conlin, Ava Marie S

2017-10-09

To protect infants from pertussis infection, the Advisory Committee on Immunization Practices (ACIP) recommends women receive the tetanus toxoid, reduced diphtheria toxoid, acellular pertussis (Tdap) vaccine between 27 and 36weeks of pregnancy. Here, we assessed the association between timing of maternal Tdap vaccination during pregnancy and acute respiratory infection (ARI) in infants <2months of age. This retrospective cohort study included 99,434 infants born to active duty military women in the Department of Defense Birth and Infant Health Registry from 2006 through 2013. Multivariable log-binomial regression was used to calculate relative risks (RRs) and 95% confidence intervals (CIs) for the association between maternal Tdap vaccination during pregnancy and infant ARI at <2months of age. Infants of mothers who received Tdap vaccination during pregnancy vs those who did not were 9% less likely to be diagnosed with an ARI at <2months of age (RR, 0.91; 95% CI, 0.84-0.99), and the risk was 17% lower if vaccination was received between 27 and 36weeks of pregnancy (RR, 0.83; 95% CI, 0.74-0.93). Similar results were observed when comparing mothers who received Tdap vaccination prior to pregnancy in addition to Tdap vaccination between 27 and 36weeks of pregnancy versus mothers who only received vaccination prior to pregnancy (RR, 0.85; 95% CI, 0.74-0.98). Maternal Tdap vaccination between 27 and 36weeks of pregnancy was consistently protective against infant ARI in the first 2months of life vs no vaccination during pregnancy, regardless of Tdap vaccination prior to pregnancy. Our findings strongly support current ACIP guidelines recommending Tdap vaccination in late pregnancy for every pregnancy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Grandmother's smoking when pregnant with the mother and asthma in the grandchild: the Norwegian Mother and Child Cohort Study.

PubMed

Magnus, Maria C; Håberg, Siri E; Karlstad, Øystein; Nafstad, Per; London, Stephanie J; Nystad, Wenche

2015-03-01

A trans-generational influence of prenatal tobacco smoke exposure on asthma development has been proposed but the evidence remains sparse. We examined the grandmother's smoking when pregnant with the mother in relation to asthma outcomes in the grandchild (current asthma at 36 months (N=53 169, cases=3013), current asthma at 7 years (N=25 394, cases=1265) and dispensed asthma medications at 7 years in the Norwegian Prescription Database (N=45 607, cases=1787)) within the Norwegian Mother and Child Cohort Study (MoBa). We calculated adjusted RR (adj. RR) and 95% CIs using log binomial regression. A total of 23.5% of mothers reported that their mother smoked when pregnant with them. The grandmother's smoking when pregnant with the mother was positively associated with asthma at 36 months (adj. RR 1.15 (95% CI 1.06 to 1.24)), asthma at 7 years (adj. RR 1.21 (95% CI 1.07 to 1.37)) and dispensed asthma medications at 7 years (adj. RR 1.15 (95% CI 1.04 to 1.26)). This positive association did not differ significantly by the mother's smoking status when pregnant with the child (p values for multiplicative interaction >0.1). The grandmother's smoking when pregnant with the mother increased the risk of asthma in the grandchild independent of the mother's smoking status. However, given limited information on the grandmother's socioeconomic status, asthma status and other factors, unmeasured confounding may be present. 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.

Prenatal and infant paracetamol exposure and development of asthma: the Norwegian Mother and Child Cohort Study

PubMed Central

Magnus, Maria C; Karlstad, Øystein; Håberg, Siri E; Nafstad, Per; Davey Smith, George; Nystad, Wenche

2016-01-01

Abstract Background: Paracetamol exposure has been positively associated with asthma development. The relative importance of prenatal vs infant exposure and confounding by indication remains elusive. We examined the association of prenatal and infant (first 6 months) paracetamol exposure with asthma development while addressing confounding by indication. Methods: We used information from the Norwegian Mother and Child Cohort Study, including 53169 children for evaluation of current asthma at 3 years, 25394 for current asthma at 7 years and 45607 for dispensed asthma medications at 7 years in the Norwegian Prescription Database. We calculated adjusted relative risks (adj. RR) and 95% confidence intervals (CI) using log-binomial regression. Results: There were independent modest associations between asthma at 3 years with prenatal paracetamol exposure (adj. RR 1.13; 95% CI: 1.02–1.25) and use of paracetamol during infancy (adj. RR 1.29; 95% CI: 1.16–1.45). The results were consistent for asthma at 7 years. The associations with prenatal paracetamol exposure were seen for different indications (pain, respiratory tract infections/influenza and fever). Maternal pain during pregnancy was the only indication that showed an association both with and without paracetamol use. Maternal paracetamol use outside pregnancy and paternal paracetamol use were not associated with asthma development. In a secondary analysis, prenatal ibuprofen exposure was positively associated with asthma at 3 years but not asthma at 7 years. Conclusions: This study provides evidence that prenatal and infant paracetamol exposure have independent associations with asthma development. Our findings suggest that the associations could not be fully explained by confounding by indication. PMID:26861478

Impact of Childhood Nutritional Status on Pathogen Prevalence and Severity of Acute Diarrhea.

PubMed

Tickell, Kirkby D; Pavlinac, Patricia B; John-Stewart, Grace C; Denno, Donna M; Richardson, Barbra A; Naulikha, Jaqueline M; Kirera, Ronald K; Swierczewski, Brett E; Singa, Benson O; Walson, Judd L

2017-11-01

Children with acute and chronic malnutrition are at increased risk of morbidity and mortality following a diarrheal episode. To compare diarrheal disease severity and pathogen prevalence among children with and without acute and chronic malnutrition, we conducted a cross-sectional study of human immunodeficiency virus-uninfected Kenyan children aged 6-59 months, who presented with acute diarrhea. Children underwent clinical and anthropometric assessments and provided stool for bacterial and protozoal pathogen detection. Clinical and microbiological features were compared using log binomial regression among children with and without wasting (mid-upper arm circumference ≤ 125 mm) or stunting (height-for-age z score ≤ -2). Among 1,363 children, 7.0% were wasted and 16.9% were stunted. After adjustment for potential confounders, children with wasting were more likely than nonwasted children to present with at least one Integrated Management of Childhood Illness danger sign (adjusted prevalence ratio [aPR]: 1.3, 95% confidence interval [CI]: 1.0 to 1.5, P = 0.05), severe dehydration (aPR: 2.4, 95% CI: 1.5 to 3.8, P < 0.01), and enteroaggregative Escherichia coli recovered from their stool (aPR: 1.8, 1.1-2.8, P = 0.02). There were no differences in the prevalence of other pathogens by wasting status after confounder adjustment. Stunting was not associated with clinical severity or the presence of specific pathogens. Wasted children with diarrhea presented with more severe disease than children without malnutrition which may be explained by a delay in care-seeking or diminished immune response to infection. Combating social determinants and host risk factors associated with severe disease, rather than specific pathogens, may reduce the disparities in poor diarrhea-associated outcomes experienced by malnourished children.

Poliovirus immunity among pregnant females aged 15-44 years, Namibia, 2010.

PubMed

Cardemil, Cristina V; Jonas, Anna; Gerber, Sue; Weldon, William C; Oberste, M Steven; Beukes, Anita; Sawadogo, Souleymane; Patel, Sadhna V; Zeko, Sikota; Muroua, Clementine; Gaeb, Esegiel; Wannemuehler, Kathleen; Goodson, James L

2014-11-01

Poliovirus (PV) antibody seroprevalence studies assess population immunity, verify an immunization program's performance and vaccine efficacy, and guide polio eradication strategy. Namibia experienced a polio outbreak among adults in 2006, yet population seroimmunity was unknown. We tested 2061 specimens from Namibian pregnant females aged 15-44 years for neutralizing antibody to PV types 1-3 (PV1-3); all females were sampled during the 2010 National HIV Sentinel Survey. We determined the proportion of females seropositive for PV antibody by 5-year age strata, and analyzed factors associated with seropositivity, including age, gravidity, human immunodeficiency virus (HIV) infection status, residence, and antiretroviral treatment, by log-binomial regression. The seroprevalence was 94.6% for PV1, 97.0% for PV2, and 85.1% for PV3. HIV-positive females had significantly lower seroprevalence than HIV-negative females for PV1 (91.8% vs 95.3%; P<.01) and PV3 (80.0% vs 86.1%; P<.01) but not for PV2 (96.4% vs 97.1%; P=.3). The prevalence ratio of seropositivity for HIV-positive females versus HIV-negative females was 0.95 (95% confidence interval [CI], .92-.98) for PV1, 0.99 (95% CI, .97-1.01) for PV2, and 0.92 (95% CI, .87-.96) for PV3. Despite relatively high PV seroprevalence, Namibia might remain at risk for a PV outbreak, particularly in lower-seroprevalence populations, such as HIV-positive females. Namibia should continue to maintain high routine polio vaccination coverage. Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Beyond access: barriers to internet health information seeking among the urban poor.

PubMed

McCloud, Rachel F; Okechukwu, Cassandra A; Sorensen, Glorian; Viswanath, K

2016-11-01

Communication inequalities deepen health disparities even when internet access is achieved. The goal of this study is to understand how a range of barriers may inhibit individuals from low socioeconomic position (SEP) from engaging with online health information even when it is freely available. Detailed data were collected from 118 low-SEP individuals from a randomized controlled trial providing internet access. Measures triangulated the health-seeking experience through internet use tracked in real-time, call log data, and self-reported barriers. Negative binomial regression models were fitted with technology and perceived predictors, and our outcome, health information seeking, and then stratified by medical status. Participants experienced a median of two computer issues (median 6 days) and two internet issues (median 6.5 days). Duration of internet problems was associated with a decrease in the rate of internet health information seeking by a factor of 0.990 (P = .03) for each additional day. Participants with a medical problem who were frustrated in their search for health information had half the rate of health information seeking of those who were not frustrated (incidence rate ratio = 0.395, P = .030). Despite IT support, participants still experienced internet connectivity issues that negatively impacted their health information seeking. Frustration in their search to find information may serve as an additional barrier to those who have medical issues. After initial internet access, a second-level digital divide emerged due to connectivity issues, highlighting the need to understand the complex network of barriers experienced by low-SEP internet users. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Self-Reported Impact of Chlamydia Testing on Subsequent Behavior: Results of an Online Survey of Young Adults in England.

PubMed

Hartney, Thomas; Baraitser, Paula; Nardone, Anthony

2015-09-01

The National Chlamydia Screening Programme performs 1.7 million tests annually among young adults in England. The effect of chlamydia screening on subsequent behavior is unknown. This study examined the self-reported impact of testing on young adults' subsequent health care-seeking and sexual behavior. We conducted a cross-sectional Web-based anonymous survey using an online panel to recruit 1521 young adults aged 16 to 24 years and resident in England. Survey questions were developed using the theory of planned behavior. Multivariate log-binomial regression was used to identify the variables associated with an impact on subsequent behavior after testing. Most respondents reported that being tested for chlamydia had a positive effect on their subsequent sexual behavior (68.6%; 422/615) or health care-seeking behavior (80.0%; 492/615). In multivariate analysis, being female and having a high level of engagement at last test were both associated with positive impacts on sexual behavior (72.7% [adjusted prevalence ratio {aPR}, 1.19; 95% confidence interval {CI}, 1.07-1.33] and 82.7% [aPR, 1.55; 95% CI, 1.27-1.89], respectively), and health care-seeking behavior (84.4% [aPR, 1.13; 95% Cl, 1.04-1.24] and 86.3% [aPR, 1.23; 95% CI, 1.07-1.41], respectively). Among respondents with minimum level of engagement, 72.4% (76/105) reported an increase in subsequent health care-seeking behavior. Chlamydia testing had a positive impact on young adults' self-reported health care-seeking and sexual behavior. This suggests that chlamydia screening has a wider effect on young adults' sexual health beyond that of treatment alone.

Measures of economic advantage associated with HPV-positive head and neck cancers among non-Hispanic black and white males identified through the National Cancer Database.

PubMed

Peterson, Caryn E; Khosla, Shaveta; Jefferson, Gina D; Davis, Faith G; Fitzgibbon, Marian L; Freels, Sally; Johnson, Timothy P; Hoskins, Kent; Joslin, Charlotte E

2017-06-01

National trends show dramatic increases in the incidence of HPV-related head and neck squamous cell carcinomas (HNSCCs) among black and white males. Using cases identified through the National Cancer Data Base, we assessed factors associated with HPV 16- or 16/18 positive HNSCCs among non-Hispanic black and white males diagnosed in the U.S. between 2009 and 2013. This sample included 21,524 HNSCCs with known HPV status. Adjusted relative risks (RRs) and 95% confidence intervals (CIs) were estimated using log-binomial regression. Compared to those with HPV-negative tumors, male patients diagnosed with HPV-positive HNSCCs were non-Hispanic white, younger at diagnosis, lived in zip-code areas with higher median household income and higher educational attainment, had private health insurance and no reported comorbidities at diagnosis. Although the risk of HPV-positive HNSCCs increased with measures of higher area-level socioeconomic status, the effect was stronger for non-Hispanic black males (RR Adjusted =1.76, 95% CI 1.49-2.09) than for whites (RR Adjusted =1.12, 95% CI 1.08-1.16). The peak age for diagnosis of HPV-positive HNSCCs occurred in those diagnosed at 45-49 years (RR Adjusted =1.57, 95% CI 1.42-1.73). Oropharyngeal tumors were strongly associated with HPV-positivity (RR Adjusted =4.32, 95% CI 4.03-4.63). In the analysis restricted to oropharyngeal anatomic sites, similar patterns persisted. In our analysis, measures of economic advantage were associated with an increased risk of HPV-positive HNSCCs. In order to develop effective interventions, greater understanding of the risk factors for HPV-positive HNSCCs is needed among both high-risk males and their healthcare providers. Copyright © 2017 Elsevier Ltd. All rights reserved.

Violence, condom breakage, and HIV infection among female sex workers in Benin, West Africa.

PubMed

Tounkara, Fatoumata K; Diabaté, Souleymane; Guédou, Fernand A; Ahoussinou, Clément; Kintin, Frédéric; Zannou, Djimon M; Kpatchavi, Adolphe; Bédard, Emmanuelle; Bietra, Raphaël; Alary, Michel

2014-05-01

To examine the relationship between violence, condom breakage, and HIV prevalence among female sex workers (FSWs). Data were obtained from the 2012 cross-sectional integrated biological and behavioral survey conducted in Benin. Multivariable log-binomial regression was used to estimate the adjusted prevalence ratios of HIV infection and condom breakage in relation to violence toward FSWs. A score was created to examine the relationship between the number of violence types reported and HIV infection. Among the 981 women who provided a blood sample, HIV prevalence was 20.4%. During the last month, 17.2%, 13.5%, and 33.5% of them had experienced physical, sexual, and psychological violence, respectively. In addition, 15.9% reported at least 1 condom breakage during the previous week. There was a significant association between all types of violence and HIV prevalence. The adjusted prevalence ratios of HIV were 1.45 (95% confidence interval [95% CI], 1.05-2.00), 1.42 (95% CI, 1.02-1.98), and 1.41 (95% CI, 1.08-1.41) among those who had ever experienced physical, sexual, and psychological violence, respectively. HIV prevalence increased with the violence score (P = 0.002, test for trend), and physical and sexual violence were independently associated with condom breakage (P = 0.010 and P = 0.003, respectively). The results show that violence is associated with a higher HIV prevalence among FSWs and that condom breakage is a potential mediator for this association. Longitudinal studies designed to analyze this relationship and specific interventions integrated to current HIV prevention strategies are needed to reduce the burden of violence among FSWs.

Violence, condom breakage and HIV infection among female sex workers in Benin, West Africa

PubMed Central

Tounkara, Fatoumata K.; Diabaté, Souleymane; Guédou, Fernand A.; Ahoussinou, Clément; Kintin, Frédéric; Zannou, Djimon M.; Kpatchavi, Adolphe; Bédard, Emmanuelle; Bietra, Raphaël; Alary, Michel

2014-01-01

Objective To examine the relationship between violence, condom breakage and HIV prevalence among female sex workers (FSWs). Methods Data were obtained from the 2012 cross-sectional integrated biological and behavioural survey conducted in Benin. Multivariable log-binomial regression was used to estimate the adjusted prevalence ratios (APRs) of HIV infection and condom breakage in relation to violence towards FSWs. A score was created to examine the relationship between the number of violence types reported and HIV infection. Results Among the 981 women who provided a blood sample, HIV prevalence was 20.4%. During the last month, 17.2%, 13.5% and 33.5% of them had experienced physical, sexual and psychological violence, respectively. In addition, 15.9% reported at least one condom breakage during the previous week. There was a significant association between all types of violence and HIV prevalence. The APRs of HIV were 1.45 (95% confidence interval [95%CI]: 1.05 – 2.00), 1.42 (95%CI: 1.02 – 1.98), and 1.41 (95%CI: 1.08 – 1.41) among those who had ever experienced physical, sexual and psychological violence, respectively. HIV prevalence increased with the violence score (p=0.002, test for trend), and physical and sexual violence were independently associated with condom breakage (p values 0.010 and 0.003, respectively). Conclusion The results show that violence is associated with a higher HIV prevalence among FSWs and that condom breakage is a potential mediator for this association. Longitudinal studies designed to analyse this relationship and specific interventions integrated to current HIV prevention strategies are needed to reduce the burden of violence among FSWs. PMID:24722385

Association of childhood adiposity measures with adulthood knee cartilage defects and bone marrow lesions: a 25-year cohort study.

PubMed

Meng, T; Thayer, S; Venn, A; Wu, F; Cicuttini, F; March, L; Dwyer, T; Halliday, A; Cross, M; Laslett, L L; Jones, G; Ding, C; Antony, B

2018-05-25

To describe the associations between childhood adiposity measures and adulthood knee cartilage defects and bone marrow lesions (BMLs) measured 25 years later. 327 participants from the Australian Schools Health and Fitness Survey (ASHFS) of 1985 (aged 7-15 years) were followed up 25 years later (aged 31-41 years). Childhood measures (weight, height and skinfolds) were collected in 1985. Body mass index (BMI), overweight status and fat mass were calculated. Participants underwent 1.5 T knee magnetic resonance imaging (MRI) during 2008-2010, and cartilage defects and BMLs were scored from knee MRI scans. Log binomial regressions were used to examine the associations. Among 327 participants (47.1% females), 21 (6.4%) were overweight in childhood. Childhood adiposity measures were associated with the increased risk of adulthood patellar cartilage defects (Weight relative risk (RR) 1.05/kg, 95% confidence interval (CI) 1.01-1.09; BMI 1.10/kg/m 2 , 1.01-1.19; Overweight 2.22/yes, 1.21-4.08; fat mass 1.11/kg, 1.01-1.22), but not tibiofemoral cartilage defects. Childhood adiposity measures were not significantly associated with adulthood knee BMLs except for the association between childhood overweight status and adulthood patellar BMLs (RR 2.87/yes, 95% CI 1.10-7.53). These significant associations persisted after adjustment for corresponding adulthood adiposity measure. Childhood adiposity measures were associated with the increased risk of adulthood patellar cartilage defects and, to a lesser extent, BMLs, independent of adulthood adiposity measures. These results suggest that adiposity in childhood has long-term effects on patellar structural abnormalities in young adults. Copyright © 2018 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Organisational justice protects against the negative effect of workplace violence on teachers' sleep: a longitudinal cohort study.

PubMed

Gluschkoff, Kia; Elovainio, Marko; Hintsa, Taina; Pentti, Jaana; Salo, Paula; Kivimäki, Mika; Vahtera, Jussi

2017-07-01

This study aimed to examine the longitudinal association of workplace violence with disturbed sleep and the moderating role of organisational justice (ie, the extent to which employees are treated with fairness) in teaching. We identified 4988 teachers participating in the Finnish Public Sector study who reported encountering violence at work. Disturbed sleep was measured in three waves with 2-year intervals: the wave preceding exposure to violence, the wave of exposure and the wave following the exposure. Data on procedural and interactional justice were obtained from the wave of exposure to violence. The associations were examined using repeated measures log-binomial regression analysis with the generalised estimating equations method, adjusting for gender and age. Exposure to violence was associated with an increase in disturbed sleep (RR 1.32 (95% CI 1.15 to 1.52)) that also persisted after the exposure (RR 1.26 (95% CI 1.07 to 1.48)). The increase was higher among teachers perceiving the managerial practices as relatively unfair (RR 1.46 (95% CI 1.01 to 2.09) and RR 1.59 (95% CI 1.04 to 2.42) for interactional and procedural justice, respectively). By contrast, working in high-justice conditions seemed to protect teachers from the negative effect of violence on sleep. Our findings show an increase in sleep disturbances due to exposure to workplace violence in teaching. However, the extent to which teachers are treated with justice moderates this association. Although preventive measures for violence should be prioritised, resources aimed at promoting justice at schools can mitigate sleep problems associated with workplace violence. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Use of Immunization Information Systems in Primary Care.

PubMed

Kempe, Allison; Hurley, Laura P; Cardemil, Cristina V; Allison, Mandy A; Crane, Lori A; Brtnikova, Michaela; Beaty, Brenda L; Pabst, Laura J; Lindley, Megan C

2017-02-01

Immunization information systems (IISs) are highly effective for increasing vaccination rates but information about how primary care physicians use them is limited. Pediatricians, family physicians (FPs), and general internists (GIMs) were surveyed by e-mail and mail from January 2015 to April 2015 from all states with an existing IIS. Providers were recruited to be representative of national provider organization memberships. Multivariable log binomial regression examined factors associated with IIS use (October 2015-April 2016). Response rates among pediatricians, FPs, and GIMs, respectively, were 75% (325/435), 68% (310/459), and 63% (272/431). A proportion of pediatricians (5%), FPs (14%), and GIMs (48%) did not know there was a state/local IIS; 81%, 72%, and 27% reported using an IIS (p<0.0001). Among those who used IISs, 64% of pediatricians, 61% of FPs, and 22% of GIMs thought the IIS could tell them a patient's immunization needs; 22%, 29%, and 51% did not know. The most frequently reported major barriers to use included the IIS not updating the electronic medical record (29%, 28%, 35%) and lack of ability to submit data electronically (22%, 27%, 31%). Factors associated with lower IIS use included FP (adjusted risk ratio=0.85; 95% CI=0.75, 0.97) or GIM (adjusted risk ratio=0.33; 95% CI=0.25, 0.42) versus pediatric specialty and older versus younger provider age (adjusted risk ratio=0.96; 95 CI%=0.94, 0.98). There are substantial gaps in knowledge of IIS capabilities, especially among GIMs; barriers to interoperability between IISs and electronic medical records affect all specialties. Closing these gaps may increase use of proven IIS functions including decision support and reminder/recall. Copyright © 2016. Published by Elsevier Inc.

Does age modify the association between physical work demands and deterioration of self-rated general health?

PubMed

Burr, Hermann; Pohrt, Anne; Rugulies, Reiner; Holtermann, Andreas; Hasselhorn, Hans Martin

2017-05-01

Objective Due to the growing proportion of older employees in the work force in several countries, the importance of age in the association between work and health is becoming increasingly relevant. Few studies have investigated whether age modifies the association of physical work demands with health. We hypothesized that the association of demanding body postures with deteriorated self-rated health (SRH) is stronger among older employees than among younger employees. Method We analyzed three 5-year cohorts in the Danish Work Environment Cohort Study comprising 8318 observations from 5204 employees (follow-up participation rate 83%) with good baseline SRH. Physical work demands were assessed as demanding body postures. Age was divided into tertiles; young (18-32 years), middle-aged (33-43 years) and old (44-59 among men and 44-54 years among women). Poor SRH ("fairly good", "poor", and "very poor") was measured with a single item. Log binomial regressions were stratified by gender. Effect modification (ie, interaction) was defined as deviation from additivity and examined by calculating the relative excess risk due to interaction (RERI). The reference group was employees aged 18-32 years with low physical exposure. Results When predicting deterioration of SRH, an interaction between demanding body postures and age was found among men [RERI: 0.75, 95% confidence interval (95% CI) 0.16-1.34, regarding the age group 44-59 years] and among women (RERI: 0.84, 95% CI 0.19-1.34, for the age group 33-43 years; and 1.17, 95% CI 0.42-1.93, for the age group 44-54 years). Conclusion The study findings suggest that demanding body postures have a stronger impact on health among older compared to younger employees.

Reports of police beating and associated harms among people who inject drugs in Bangkok, Thailand: a serial cross-sectional study

PubMed Central

2013-01-01

Background Thailand has for years attempted to address illicit drug use through aggressive drug law enforcement. Despite accounts of widespread violence by police against people who inject drugs (IDU), the impact of police violence has not been well investigated. In the wake of an intensified police crackdown in 2011, we sought to identify the prevalence and correlates of experiencing police beating among IDU in Bangkok. Methods Community-recruited samples of IDU in Bangkok were surveyed between June 2009 and October 2011. Multivariate log-binomial regression was used to identify factors associated with reporting police beating. Results In total, 639 unique IDU participated in this serial cross-sectional study, with 240 (37.6%) participants reporting that they had been beaten by police. In multivariate analyses, reports of police beating were associated with male gender (Adjusted Prevalence Ratio [APR] = 4.43), younger age (APR = 1.69), reporting barriers to accessing healthcare (APR = 1.23), and a history of incarceration (APR = 2.51), compulsory drug detention (APR = 1.22) and syringe sharing (APR = 1.44), and study enrolment in 2011 (APR = 1.27) (all p < 0.05). Participants most commonly reported police beating during the interrogation process. Conclusions A high proportion of IDU in Bangkok reported having been beaten by the police. Experiencing police beating was independently associated with various indicators of drug-related harm. These findings suggest that the over-reliance on enforcement-based approaches is contributing to police-perpetrated abuses and the perpetuation of the HIV risk behaviour among Thai IDU. PMID:23924324

Intracerebral hemorrhage and sleep-disordered breathing.

PubMed

Lisabeth, Lynda D; Scheer, Richard V; Li, Chengwei; Case, Erin; Chervin, Ronald D; Zahuranec, Darin B; Morgenstern, Lewis B; Garcia, Nelda M; Tower, Susan; Brown, Devin L

2018-06-01

Limited data are available on sleep-disordered breathing (SDB) following intracerebral hemorrhage (ICH). Our aim was to characterize the objective measures of post-ICH SDB and questionnaire-reported pre-ICH sleep characteristics, overall and by ethnicity. Participants with ICH who were enrolled in the population-based Brain Attack Surveillance in Corpus Christi project (2010-2016) reported their pre-ICH sleep duration and completed the Berlin Questionnaire to characterize pre-ICH risk of SDB. A subsample was screened for SDB (respiratory event index ≥10) using ApneaLink Plus portable monitoring. Ethnic differences in post-ICH SDB or questionnaire-reported pre-ICH sleep characteristics were assessed using a log binomial model or a linear regression model or a Fisher's exact test. ICH cases (n = 298) were enrolled (median age = 68 years, 67% Mexican American). Among 62 cases with complete ApneaLink data, median time to post-ICH SDB screening was 11 days (IQR: 6, 19). Post-ICH SDB prevalence was 46.8% (95% CI: 34.4-59.2), and this rate did not differ by ethnicity (p = 1.0). Berlin Questionnaires for 109 of the 298 ICH cases (36.6% (95% CI: 31.1-42.0)) suggested a high risk for pre-ICH SDB, and the median pre-ICH sleep duration was eight hours (IQR: 6, 8). After adjusting for confounders, there was no difference in ethnicity in high risk for pre-ICH SDB or pre-ICH sleep duration. Nearly half of the patients had objective confirmation of SDB after ICH, and more than one-third had questionnaire evidence of high risk for pre-ICH SDB. Opportunities to address SDB may be common both before and after ICH. Copyright © 2018 Elsevier B.V. All rights reserved.

Association of filaggrin variants with asthma and rhinitis: is eczema or allergic sensitization status an effect modifier?

PubMed Central

Ziyab, Ali H.; Karmaus, Wilfried; Zhang, Hongmei; Holloway, John W.; Steck, Susan E.; Ewart, Susan; Arshad, Syed Hasan

2014-01-01

Background Associations of filaggrin (FLG) variants with asthma and rhinitis have been shown to be modulated by eczema status. However, it is unknown whether allergic sensitization status modifies this association. The aim of this study was to determine whether FLG variants need eczema and/or allergic sensitization as a necessary component to execute its adverse effect on coexisting and subsequent asthma and rhinitis. Methods Repeated measurements of asthma, rhinitis, eczema, and allergic sensitization (documented by skin prick tests) at ages 1, 2, 4, 10, and 18 years were ascertained in the Isle of Wight birth cohort (n = 1,456). FLG haploinsufficiency was defined as having at least the minor allele of R501X, 2282del4, or S3247X variants. Log binomial regression models were used to test associations and statistical interactions. Results FLG variants increased the risk of asthma (RR = 1.39, 95% CI: 1.06 – 1.80) and rhinitis (RR = 1.37, 95% CI: 1.16 – 1.63). In delayed effect models, ‘FLG variants plus allergic sensitization’ and ‘FLG variants plus eczema’ increased the risk of subsequent asthma by 4.93-fold (95% CI: 3.61 – 6.71) and 3.33-fold (95% CI: 2.45 – 4.51), respectively, during the first 18 years of life. In contrast, neither eczema nor allergic sensitization in combination with FLG variants increased the risk of later rhinitis. Conclusions Allergic sensitization and eczema modulated the association between FLG variants and asthma, but not rhinitis. Results of our study imply that the mechanisms and pathways through which FLG variants predispose to increased risk of asthma and rhinitis may be different. PMID:25277085

DNA methylation of the filaggrin gene adds to the risk of eczema associated with loss-of-function variants

PubMed Central

Ziyab, A. H.; Karmaus, W.; Holloway, J. W.; Zhang, H.; Ewart, S.; Arshad, S. H.

2012-01-01

Background Loss-of-function variants within the filaggrin gene (FLG) are associated with a dysfunctional skin barrier that contributes to the development of eczema. Epigenetic modifications, such as DNA methylation, are genetic regulatory mechanisms that modulate gene expression without changing the DAN sequence. Objectives To investigate whether genetic variants and adjacent differential DNA methylation within the FLG gene synergistically act on the development of eczema. Methods A subsample (n = 245, only females aged 18 years) of the Isle of Wight birth cohort participants (n = 1,456) had available information for FLG variants R501X, 2282del4, and S3247X and DNA methylation levels for 10 CpG sites within the FLG gene. Log-binomial regression was used to estimate the risk ratios (RRs) of eczema associated with FLG variants at different methylation levels. Results The period prevalence of eczema was 15.2% at age 18 years and 9.0% of participants were carriers (heterozygous) of FLG variants. Of the 10 CpG sites spanning the genomic region of FLG, methylation levels of CpG site ‘cg07548383’ showed a significant interaction with FLG sequence variants on the risk for eczema. At 86% methylation level, filaggrin haploinsufficient individuals had 5.48-fold increased risk of eczema when compared to those with wild type FLG genotype (p-value = 0.0008). Conclusions Our novel results indicated that the association between FLG loss-of-function variants and eczema is modulated by DNA methylation. Simultaneously assessing the joint effect of genetic and epigenetic factors within the FLG gene further highlights the importance of this genomic region for eczema manifestation. PMID:23003573

Executive function associated with sexual risk in young South African women: Findings from the HPTN 068 cohort

PubMed Central

Pettifor, Audrey; Duta, Mihaela; Demeyere, Nele; Wagner, Ryan G.; Selin, Amanda; MacPhail, Catherine; Laeyendecker, Oliver; Hughes, James P.; Stein, Alan; Tollman, Stephen; Kahn, Kathleen

2018-01-01

Purpose Heightened sexual risk in adolescence and young adulthood may be partially explained by deficits in executive functioning, the set of cognitive processes used to make reasoned decisions. However, the association between executive function and sexual risk is understudied among adolescent girls and young women, particularly in low- and middle-income countries. Methods In a cohort of 853 young women age 18–25 in rural Mpumalanga province, South Africa, we evaluated executive function with three non-verbal cognitive tests: I. a rule-finding test, II. a trail-making test, and III. a figure drawing test. Using log-binomial regression models, we estimated the association between lower executive function test scores and indicators of sexual risk (unprotected sex acts, concurrent partnerships, transactional sex, and recent HSV-2 infection). Results In general, young women with lower executive function scores reported higher frequencies of sexual risk outcomes, though associations tended to be small with wide confidence intervals. Testing in the lowest quintile of Test I was associated with more unprotected sex [aPR (95% CI): 1.4 (1.0, 1.8)]. Testing in the lowest quintile of Test II was associated with more concurrent relationships and transactional sex [aPR (95% CI): 1.6 (1.1, 2.5) and 1.7 (1.3, 2.4), respectively], and testing in the lowest four quintiles of Test III was associated with more concurrent relationships [aPR (95% CI): 1.7 (1.0, 2.7)]. Conclusions These results demonstrate an association between low executive function and sexual risk in South African young women. Future work should seek to understand the nature of this association and whether there is promise in developing interventions to enhance executive function to reduce sexual risk. PMID:29608615

Widespread Bordetella parapertussis Infections-Wisconsin, 2011-2012: Clinical and Epidemiologic Features and Antibiotic Use for Treatment and Prevention.

PubMed

Koepke, Ruth; Bartholomew, Michael L; Eickhoff, Jens C; Ayele, Roman A; Rodd, Diane; Kuennen, Joan; Rosekrans, Jean; Warshauer, David M; Conway, James H; Davis, Jeffrey P

2015-11-01

During October 2011-December 2012, concurrent with a statewide pertussis outbreak, 443 Bordetella parapertussis infections were reported among Wisconsin residents. We examined clinical features of patients with parapertussis and the effect of antibiotic use for treatment and prevention. Patients with polymerase chain reaction results positive for B. parapertussis reported during October 2011-May 2012 were interviewed regarding presence and durations of pertussis-like symptoms and receipt of azithromycin treatment. Data regarding acute cough illnesses and receipt of azithromycin prophylaxis among parapertussis patient household members (HHMs) were also collected. Using multivariate repeated measures log-binomial regression analysis, we examined associations of treatment receipt by the HHM with the earliest illness onset and prophylaxis receipt among other HHMs with the presence of any secondary cough illnesses in the household. Among 218 patients with parapertussis, pertussis-like symptoms were frequently reported. Illness durations were significantly shorter among patients with treatment initiated 0-6 days after cough onset, compared with nonrecipients (median durations: 10 vs 19 days, P = .002). Among 361 HHMs from 120 households, compared with nonrecipients, prompt prophylaxis of HHMs was associated with no secondary cough illnesses (relative risk: 0.16; 95% confidence interval, .04-.69). Bordetella parapertussis infection causes pertussis-like illness that might be misclassified as pertussis if B. parapertussis testing is not performed. Prompt treatment might shorten illness duration, and prompt HHM prophylaxis might prevent secondary illnesses. Further study is needed to evaluate antibiotic effectiveness for preventing parapertussis and to determine risks and benefits of antibiotic use. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Clinical prediction rule for delayed hemothorax after minor thoracic injury: a multicentre derivation and validation study

PubMed Central

Émond, Marcel; Guimont, Chantal; Chauny, Jean-Marc; Daoust, Raoul; Bergeron, Éric; Vanier, Laurent; Moore, Lynne; Plourde, Miville; Kuimi, Batomen; Boucher, Valérie; Allain-Boulé, Nadine; Le Sage, Natalie

2017-01-01

Background: About 75% of patients with minor thoracic injury are discharged after an emergency department visit. However, complications such as delayed hemothorax can occur. We sought to derive and validate a clinical decision rule to predict hemothorax in patients discharged from the emergency department. Methods: We conducted a 6-year prospective cohort study in 4 university-affiliated emergency departments. Patients aged 16 years or older presenting with a minor thoracic injury were assessed at 5 time points (initial visit and 7, 14, 30 and 90 d after the injury). Radiologists' reports were reviewed for the presence of hemothorax. We used log-binomial regression models to identify predictors of hemothorax. Results: A total of 1382 patients were included: 830 in the derivation phase and 552 in the validation phase. Of these, 151 (10.9%) had hemothorax at the 14-day follow-up. Patients 65 years of age or older represented 25.3% (210/830) and 23.7% (131/552) of the derivation and validation cohorts, respectively. The final clinical decision rule included a combination of age (> 70 yr, 2 points; 45-70 yr, 1 point), fracture of any high to mid thorax rib (ribs 3-9, 2 points) and presence of 3 or more rib fractures (1 point). Twenty (30.8%) of the 65 high-risk patients (score ≥ 4) experienced hemothorax during the follow-up period. The clinical decision rule had a high specificity (90.7%, 95% confidence interval 87.7%-93.1%) in this high-risk group, thus guiding appropriate post-emergency care. Interpretation: One patient out of every 10 presented with delayed hemothorax after discharge from the emergency department. Implementation of this validated clinical decision rule for minor thoracic injury could guide emergency discharge plans. PMID:28611156

Possible Common Aetiology behind Maternal Preeclampsia and Congenital Heart Defects in the Child: a Cardiovascular Diseases in Norway Project Study.

PubMed

Brodwall, Kristoffer; Leirgul, Elisabeth; Greve, Gottfried; Vollset, Stein Emil; Holmstrøm, Henrik; Tell, Grethe S; Øyen, Nina

2016-01-01

The aetiology of congenital heart defects (CHD) is mostly unknown, but maternal factors may modify the infant risk of CHD. We investigated the association between maternal preeclampsia and offspring risk of severe CHD in a nation-wide cohort study. Information on all births registered in the Medical Birth Registry of Norway, 1994-2009, was completed with information on CHD diagnoses from national health registries and the Cardiovascular Diseases in Norway Project (CVDNOR). Among 914 703 singleton births without chromosomal abnormalities, 32 864 (3.6%) were born after a pregnancy with preeclampsia. The preeclampsia was diagnosed before the 34th week of pregnancy (early-onset preeclampsia) in 2618 (8.0% of preeclamptic pregnancies). CHDs were diagnosed in 10 691 infants; of these, 2473 had severe CHD. The risk of severe CHD was compared between births with and without maternal preeclampsia and estimated with binomial log-linear regression. When adjusting for year of birth, maternal age, parity, and pregestational diabetes, the risk ratio (RR) for severe CHD in offspring of mothers with any preeclampsia was 1.3 [95% confidence interval (CI) 1.1, 1.5], and in pregnancies with early-onset preeclampsia, the RR was 2.8 (95% CI 1.8, 4.4). The association between early-onset preeclampsia and specific types of severe CHD was stronger for atrioventricular septal defects (AVSD), with adjusted RR 13.5 (95% CI 6.8, 26.8). Early-onset preeclampsia was strongly associated with infant risk of severe CHD, specifically; the risk of AVSD was 15-fold higher if the mother was diagnosed with early-onset preeclampsia, suggesting common aetiological factors for early-onset preeclampsia and erroneous fetal heart development. © 2015 John Wiley & Sons Ltd.

Predictors of Recall Certainty of Dates of Analgesic Medication Use in Pregnancy

PubMed Central

Radin, Rose G.; Mitchell, Allen A.; Werler, Martha M.

2012-01-01

Purpose Recalled dates of medication use are difficult to validate, particularly for over-the-counter (OTC) medications. We evaluated mothers’ recall certainty as an approximation of the accuracy of their recalled exposures. Methods We used data from the Slone Epidemiology Center Birth Defects Study collected by retrospective interview of women about pregnancy medication use. For each medication reported, women were asked to report the dates of their use and how certain they were of their reported dates. For this analysis, 32,107 reports from 14,577 analgesic users were categorized as ‘high’ or ‘low’ recall certainty if they considered a reported date as exact or estimated, respectively. Patterns of analgesic use, maternal demographics, and health behaviors were explored as predictors of high recall certainty of dates of analgesic use. We used log-binomial regression with the generalized estimating equations extension to account for multiple reports per subject in estimating prevalence ratios (PR) and 95% confidence intervals. Results Relative to episodes of short-term routine use (≥4 times/week for ≤30 days), high recall certainty was more likely for episodes of a single dose (prescription PR=1.92 (1.61, 2.27); OTC PR=3.65 (3.03, 4.40)) and less likely for episodes of occasional use (prescription PR=0.10 (0.05, 0.18); OTC PR=0.65 (0.53, 0.79)). The association of chronic routine use with high recall certainty was inverse among prescription analgesics and positive among OTC analgesics (prescription PR=0.56 (0.40, 0.80); OTC PR=2.46 (1.92, 3.42)). Conclusions Some characteristics that were associated with recall accuracy in previous studies were also associated with recall certainty in this study. PMID:22674801

Differences in acute retroviral syndrome by HIV-1 subtype in a multicentre cohort study in Africa

PubMed Central

Sanders, Eduard J.; Price, Matthew A.; Karita, Etienne; Kamali, Anatoli; Kilembe, William; Bekker, Linda-Gail; Lakhi, Shabir; Inambao, Mubiana; Anzala, Omu; Fast, Patricia E.; Gilmour, Jill; Powers, Kimberly A.

2017-01-01

Objective: Symptoms of acute retroviral syndrome (ARS) may be used to identify patients with acute HIV-1 infection who seek care. ARS symptoms in African adults differ by region. We assessed whether reporting of ARS was associated with HIV-1 subtype in a multicentre African cohort study representing countries with predominant HIV-1 subtypes A, C, and D. Methods: ARS symptoms were assessed in adults enrolling at least 6 weeks after the estimated date of infection in an acute and early HIV-1 infection cohort study. HIV-1 subtype was determined by POL genotyping. We used log-binomial regression to compare ARS symptom prevalence among those with subtype A vs. C or D, adjusting for sex, time since enrolment, and enrolment viral load. Results: Among 183 volunteers ascertained within 6 weeks after estimated date of infection, 77 (42.0%) had subtype A, 83 (45.4%) subtype C, and 23 (12.6%) subtype D infection. Individuals with subtype A were 1.40 (95% confidence interval: 1.17, 1.68) times as likely as individuals with subtypes C or D to report any ARS symptoms; each individual symptom other than rash was also more prevalent in subtype A than in subtype C or D, with prevalence ratios ranging from 1.94 (1.40, 2.70) for headache to 4.92 (2.24, 10.78) for lymphadenopathy. Conclusion: Individuals with subtype A were significantly more likely than individuals with subtypes C or D to report any ARS symptoms. HIV-1 subtypes may help explain differences in ARS that have been observed across regions in Africa, and may impact the yield of symptom-based screening strategies for acute HIV infection detection. PMID:29028659

Unmetabolized Folic Acid, Tetrahydrofolate, and Colorectal Adenoma Risk.

PubMed

Rees, Judy R; Morris, Carolyn B; Peacock, Janet L; Ueland, Per M; Barry, Elizabeth L; McKeown-Eyssen, Gail E; Figueiredo, Jane C; Snover, Dale C; Baron, John A

2017-08-01

In a randomized trial of folic acid supplementation for the prevention of colorectal adenomas, we previously found indications of increased risk during later treatment and follow-up. This could have been due to the unmetabolized folic acid (UFA) or natural reduced and methylated folates (mF) to which it is metabolized. In post hoc analyses, we measured mF (the sum of 5-methyl-tetrahydrofolate and 4-alfa-hydroxy-5-methyl-THF) and UFA concentrations in the serum of 924 participants. Using binomial regression models with a log link, we assessed the associations between plasma mF or UFA and adenoma occurrence. We found no association between plasma mF or UFA and overall adenoma risk. However, during later follow-up, the prespecified, composite endpoint of high-risk findings (advanced or multiple adenomas) was positively associated with plasma mF ( P linear trend = 0.009), with a 58% increased risk for participants in the upper versus lowest quartile. An irregular association was seen with plasma UFA, with suggestions of an inverse trend ( P linear trend =0.049). A modest, significant inverse association was also seen between mF and risk of serrated lesions, with a 39% lower risk for upper versus lower quartile participants ( P linear trend = 0.03). In conclusion, during the later follow-up period in which folic acid supplementation was previously seen to increase the risk of advanced and multiple adenomas, higher serum mF was associated with a higher risk of multiple and/or advanced adenomas, but no clear indication that UFA played a direct role. There were indications that higher mF was associated with reduced risk of serrated polyps. Cancer Prev Res; 10(8); 451-8. ©2017 AACR . ©2017 American Association for Cancer Research.

Maternal Folate Intake during Pregnancy and Childhood Asthma in a Population-based Cohort

PubMed Central

Magnus, Maria C.; Karlstad, Øystein; Haugen, Margaretha; Refsum, Helga; Ueland, Per M.; McCann, Adrian; Nafstad, Per; Håberg, Siri E.; Nystad, Wenche; London, Stephanie J.

2017-01-01

Rationale: A potential adverse effect of high folate intake during pregnancy on children’s asthma development remains controversial. Objectives: To prospectively investigate folate intake from both food and supplements during pregnancy and asthma at age 7 years when the diagnosis is more reliable than at preschool age. Methods: This study included eligible children born 2002–2006 from the Norwegian Mother and Child Cohort Study, a population-based pregnancy cohort, linked to the Norwegian Prescription Database. Current asthma at age 7 was defined by asthma medications dispensed at least twice in the year (1,901 cases; n = 39,846) or by maternal questionnaire report (1,624 cases; n = 28,872). Maternal folate intake was assessed with a food frequency questionnaire validated against plasma folate. We used log-binomial and multinomial regression to calculate adjusted relative risks with 95% confidence intervals. Measurements and Main Results: Risk of asthma was increased in the highest versus lowest quintile of total folate intake with an adjusted relative risk of 1.23 (95% confidence interval, 1.06–1.44) that was similar for maternally reported asthma. Mothers in the highest quintile had a relatively high intake of food folate (median, 308; interquartile range, 241–366 μg/d) and nearly all took at least 400 μg/d of supplemental folic acid (median, 500; interquartile range, 400–600 μg/d). Conclusions: In this large prospective population-based cohort with essentially complete follow-up, pregnant women taking supplemental folic acid at or above the recommended dose, combined with a diet rich in folate, reach a total folate intake level associated with a slightly increased risk of asthma in children. PMID:27518161

The role of maternal education in the 15-year trajectory of malnutrition in children under 5 years of age in Bangladesh.

PubMed

Hasan, Md Tanvir; Soares Magalhaes, Ricardo J; Williams, Gail M; Mamun, Abdullah A

2016-10-01

Malnutrition in children under 5 years of age (U5s) is a serious public health problem in low- and middle-income countries including Bangladesh. Improved maternal education can contribute effectively to reduce child malnutrition. We examined the long-term impact of maternal education on the risk of malnutrition in U5s and quantified the level of education required for the mothers to reduce the risk. We used pooled data from five nationwide demographic and health surveys conducted in 1996-1997, 1999-2000, 2004, 2007 and 2011 in Bangladesh involving 28 941 U5s. A log-binomial regression model was used to examine the association between maternal education (no education, primary, secondary or more) and malnutrition in children, measured by stunting, underweight and wasting controlling for survey time, maternal age, maternal body mass index, maternal working status, parity, paternal education and wealth quintile. An overall improvement in maternal educational attainment was observed between 1996 and 2011. The prevalence of malnutrition although decreasing was consistently high among children of mothers with lower education compared with those of mothers with higher education. In adjusted models incorporating time effects, children of mothers with secondary or higher education were at lower risk of childhood stunting [risk ratio (RR): 0.86, 95% confidence interval (CI): 0.81, 0.89], underweight (RR: 0.83, 95% CI: 0.78, 0.88) and wasting (RR: 0.82, 95% CI: 0.74, 0.91) compared with children of mothers with no education. We demonstrated the importance of promoting women's education at least up to the secondary level as a means to tackle malnutrition in Bangladesh. © 2015 John Wiley & Sons Ltd.

Peripheral neuropathy in HIV-infected and uninfected patients in Rakai, Uganda.

PubMed

Saylor, Deanna; Nakigozi, Gertrude; Nakasujja, Noeline; Robertson, Kevin; Gray, Ronald H; Wawer, Maria J; Sacktor, Ned

2017-08-01

To determine the prevalence, risk factors, and functional impairment associated with peripheral neuropathy in a prospective cohort of adults in rural Uganda. Eight hundred participants (400 HIV- and 400 antiretroviral-naive HIV+) in the Rakai Community Cohort Study underwent detailed neurologic evaluations including assessment of neuropathy symptoms, functional measures (Patient Assessment of Own Functioning Inventory and Karnofsky Performance Status scores), and neurologic evaluation by a trained medical officer. Neuropathy was defined as ≥1 subjective symptom and ≥1 sign of neuropathy on examination. Neuropathy risk factors were assessed using log binomial regression. Fifty-three percent of participants were men, with a mean (SD) age of 35 (8) years. Neuropathy was present in 13% of the cohort and was more common in HIV+ vs HIV- participants (19% vs 7%, p < 0.001). Older age (relative risk [RR] 1.04, 95% confidence interval [CI] 1.02-1.06), female sex (RR 1.49, 95% CI 1.04-2.15), HIV infection (RR 2.82, 95% CI 1.86-4.28), tobacco use (RR 1.59, 95% CI 1.02-2.48), and prior neurotoxic medication use (RR 2.08, 95% CI 1.07-4.05) were significant predictors of neuropathy in the overall cohort. Only older age was associated with neuropathy risk in the HIV+ (RR 1.03, 95% CI 1.01-1.05) and HIV- (RR 1.06, 95% CI 1.02-1.10) cohorts. Neuropathy was associated with impaired functional status on multiple measures across all participant groups. Peripheral neuropathy is relatively common and associated with impaired functional status among adults in rural Uganda. Older age, female sex, and HIV infection significantly increase the risk of neuropathy. Neuropathy may be an underrecognized but important condition in rural Uganda and warrants further study. © 2017 American Academy of Neurology.

Prevalence and risk factors for skin diseases among antiretroviral-naïve HIV-infected pregnant women in Dar es Salaam, Tanzania.

PubMed

Shayo, Grace A; Moshiro, Candida; Spiegelman, Donna; Mugusi, Ferdinand M; Chalamilla, Guerino; Msamanga, Gernard; Hawkins, Claudia; Fawzi, Wafaie

2014-10-01

Reduced cell-mediated immunity associated with pregnancy may cause a flaring or exacerbation of some skin conditions. Little is known about the magnitude of and risk factors for skin diseases among human immunodeficiency virus (HIV)-infected antiretroviral therapy-naïve pregnant women. Cross-sectional study of 1078 HIV-infected antiretroviral therapy-naïve pregnant women was conducted in Dar es Salaam, Tanzania. Skin diagnoses were mainly clinical. Log-binomial regression models were used to explore factors associated with the outcomes. About 84% of the women were in World Health Organization (WHO) HIV stage I. Median CD4(+) count was 405 × 10(6)  cells/l. The prevalence of any skin disease was 18%. Fungal infections (11%), genital ulcers (7%), and viral infections (5%) were the most common skin conditions. Skin infections were 2.64 times more common in HIV stage III (95% CI 1.51-4.62) compared to stage I. Fungal infections were 1.77 times common among single, divorced, and widowed women than among married women (95% CI 1.16-2.69), 2.8 times common among women in HIV stage III (95% CI 1.18-6.64) compared to stage I. Genital ulcers were significantly more common among women whose source of income was their own compared with those who got full support from partners, and among WHO HIV stage III disease compared to stage I. The burden of skin diseases was relatively low. Advanced HIV stage was associated with a range of skin conditions. CD4(+) cell count was not related to skin infection prevalence. © 2014 The International Society of Dermatology.

Sleep Duration, Restfulness, and Screens in the Sleep Environment

PubMed Central

Davison, Kirsten K.; Franckle, Rebecca L.; Ganter, Claudia; Gortmaker, Steven L.; Smith, Lauren; Land, Thomas; Taveras, Elsie M.

2015-01-01

BACKGROUND AND OBJECTIVE: Associations of inadequate sleep with numerous health outcomes among youth necessitate identifying its modifiable determinants. Television (TV) has been associated with sleep curtailment, but little is known about small screens (eg, smartphones), which can be used in bed and emit notifications. Therefore, we examined associations of different screens in sleep environments with sleep duration and perceived insufficient rest or sleep. METHODS: Participants included 2048 fourth- and seventh-graders participating in the Massachusetts Childhood Obesity Research Demonstration Study in 2012 to 2013. Using linear and log binomial regression, we examined cross-sectional associations of small screens and TVs in sleep environments and screen time with weekday sleep duration and perceived insufficient rest or sleep in the past week. RESULTS: Children who slept near a small screen (compared with never) reported 20.6 fewer minutes of sleep (95% confidence interval [CI], −29.7 to −11.4) and had a higher prevalence of perceived insufficient rest or sleep (prevalence ratio, 1.39; 95% CI, 1.21 to 1.60). Children who slept in a room with a TV (compared with no TV) reported 18.0 fewer minutes of sleep (95% CI, −27.9 to −8.1). TV or DVD viewing and video or computer game playing were associated with both sleep outcomes (P < .01). Some associations were stronger among Hispanic, non-Hispanic black, and older children (P < .05 for heterogeneity). CONCLUSIONS: Sleeping near a small screen, sleeping with a TV in the room, and more screen time were associated with shorter sleep durations. Presence of a small screen, but not a TV, in the sleep environment and screen time were associated with perceived insufficient rest or sleep. These findings caution against unrestricted screen access in children’s bedrooms. PMID:25560435

Trends in provider-initiated versus spontaneous preterm deliveries, 2004–2013

PubMed Central

Ada, Melissa L.; Hacker, Michele R.; Golen, Toni H.; Haviland, Miriam J.; Shainker, Scott A.; Burris, Heather H.

2017-01-01

Objectives 1) To estimate the proportion of preterm deliveries at a tertiary perinatal center that were provider-initiated vs. spontaneous before and after a 2009 policy to reduce elective early-term deliveries. 2) To evaluate if shifts in type of preterm delivery varied by race/ethnicity. Methods We performed a retrospective cohort study of preterm deliveries over a 10-year period, 2004–2013, including detailed review of 929 of 5,566 preterm deliveries to designate each delivery as provider-initiated or spontaneous. We dichotomized the time period into early (2004–2009) and late (2010–2013). We used log-binomial regression to calculate adjusted risk ratios. Results Of the 46,981 deliveries, 5,566 (11.8%) were preterm, with a significant reduction in the overall incidence of preterm delivery from 12.3% to 11.2% (P=0.0003). Among the 929 preterm deliveries analyzed, there was a reduction in the proportion of provider-initiated deliveries from 48.3% to 41.8% that was not statistically significant. The proportion of provider-initiated preterm deliveries among black, but not white, women declined from 50.8% to 39.7% (adjusted RR: 0.66; 95%CI: 0.45–0.97). This coincided with a larger reduction in overall preterm deliveries among black women (16.2% to 12.8%) vs. white women (12.3% to 11.2%) (P interaction=0.038). By 2013, the incidence of preterm deliveries had decreased for both black (12.1%) and white women (11.4%) and the difference was no longer statistically significant (P=0.7). Conclusion We found a reduction in preterm deliveries after a policy targeted at reducing elective early-term deliveries in 2009 that coincided with reductions in the proportion of provider-initiated preterm deliveries, especially among black women. PMID:28749488

Social capital, tolerance of diversity and adherence to Mediterranean diet: the Rhea Mother-Child Cohort in Crete, Greece.

PubMed

Kritsotakis, George; Chatzi, Leda; Vassilaki, Maria; Georgiou, Vaggelis; Kogevinas, Manolis; Philalithis, Anastassios E; Koutis, Antonis

2015-05-01

To estimate the associations of individual maternal social capital and social capital dimensions (Participation in the Community, Feelings of Safety, Value of Life and Social Agency, Tolerance of Diversity) with adherence to the Mediterranean diet during pregnancy. This is a cross-sectional analysis of data from a prospective mother-child cohort (Rhea Study). Participants completed a social capital questionnaire and an FFQ in mid-pregnancy. Mediterranean diet adherence was evaluated through an a priori score ranging from 0 to 8 (minimal-maximal adherence). Maternal social capital scores were categorized into three groups: the upper 10 % was the high social capital group, the middle 80 % was the medium and the lowest 10 % was the low social capital group. Multivariable log-binomial and linear regression models adjusted for confounders were performed. Heraklion, Crete, Greece. A total of 377 women with singleton pregnancies. High maternal Total Social Capital was associated with an increase of almost 1 point in Mediterranean diet score (highest v. lowest group: β coefficient=0·95, 95 % CI 0·23, 1·68), after adjustment for confounders. Similar dose-response effects were noted for the scale Tolerance of Diversity (highest v. lowest group: adjusted β coefficient=1·08, 95 % CI 0·39, 1·77). Individual social capital and tolerance of diversity are associated with adherence to the Mediterranean diet in pregnancy. Women with higher social capital may exhibit a higher sense of obligation to themselves and to others that may lead to proactive nutrition-related activities. Less tolerant women may not provide the opportunity to new healthier, but unfamiliar, nutritional recommendations to become part of their regular diet.

Mediterranean diet adherence during pregnancy and fetal growth: INMA (Spain) and RHEA (Greece) mother-child cohort studies.

PubMed

Chatzi, Leda; Mendez, Michelle; Garcia, Raquel; Roumeliotaki, Theano; Ibarluzea, Jesús; Tardón, Adonina; Amiano, Pilar; Lertxundi, Aitana; Iñiguez, Carmen; Vioque, Jesus; Kogevinas, Manolis; Sunyer, Jordi

2012-01-01

Dietary intake of specific nutrients or food groups during pregnancy could influence fetal growth, but scant evidence is available on effects of dietary patterns. The aim of this study was to evaluate the impact of Mediterranean diet (MD) adherence during pregnancy on fetal growth in two population-based mother-child cohorts in Spain and Greece. We studied 2461 mother-newborn pairs from the Spanish multi-centre 'INMA' study (Atlantic area: INMA-Atlantic; Mediterranean area: INMA-Mediterranean), and 889 pairs from the 'RHEA' study in Crete, Greece. Maternal diet during pregnancy was assessed by FFQ and MD adherence was evaluated through an a priori score. Fetal growth restriction was based on a customised model, and multivariate log-binomial and linear regression models were used to adjust for several confounders. MD scores differ significantly between the cohorts with women in INMA-Atlantic reporting higher intakes of fish and dairy products, while women in the Mediterranean area reported higher intakes of cereals, vegetables and fruits. Women with high MD adherence had a significantly lower risk of delivering a fetal growth-restricted infant for weight (risk ratios: 0·5; 95 % CI 0·3, 0·9) in the INMA-Mediterranean cohort. Stratified analysis by smoking revealed that higher MD adherence increased birth weight and birth length in smoking mothers, whereas this effect was not apparent in non-smoking mothers. The results of the present study show that several types of MD exist across European Mediterranean regions. High MD adherence may modify the detrimental effect of smoking on birth size, but overall effects of diet were not universal for the studies in this analysis.

Variation in symptoms of depression and anxiety in midlife women by menopausal status.

PubMed

Mulhall, Stephanie; Andel, Ross; Anstey, Kaarin J

2018-02-01

To examine the association between menopausal status and the risk of symptoms of depression and anxiety in a community-based sample of Australian midlife women. Female participants (mean age 50.6±1.5) who were premenopausal (n=237), perimenopausal (n=249) or naturally postmenopausal (n=225) were drawn from the Personality and Total Health (PATH) Through Life Project, a longitudinal study. Symptoms of depression and anxiety were measured using the Goldberg Depression Scale and Goldberg Anxiety Scale. Generalised linear regression models with a negative binomial log link were used. Relative to premenopause and after adjusting for all relevant covariates, being perimenopausal was associated with increased risk of greater symptoms of depression (incidence rate ratio [IRR]=1.29, p=0.001), while being postmenopausal was associated with increased risk of greater symptoms of anxiety (IRR=1.15, p=0.041). Being perimenopausal or postmenopausal was associated with an increased risk of greater symptoms of depression (IRR=1.35, p=0.008; IRR=1.31, p=0.029) and anxiety (IRR=1.22, p=0.030; IRR=1.32, p=0.006) in women without a history of probable major depressive disorder or generalised anxiety disorder. Risk of symptoms did not differ with menopausal status in women with this history. Menopausal status is associated with the risk of symptoms of depression and anxiety. There is a greater likelihood of increased symptoms of depression during perimenopause and symptoms of anxiety during postmenopause. In women without a history of depression or anxiety, the perimenopause and postmenopausal stages are associated with increased risk of greater symptoms of anxiety and depression relative to premenopause. Copyright © 2017 Elsevier B.V. All rights reserved.

Alcohol Use and Associations With Biological Markers and Self-Reported Indicators of Unprotected Sex in Human Immunodeficiency Virus-Positive Female Sex Workers in Mombasa, Kenya.

PubMed

White, Darcy; Wilson, Kate S; Masese, Linnet N; Wanje, George; Jaoko, Walter; Mandaliya, Kishorchandra; Richardson, Barbra A; Kinuthia, John; Simoni, Jane M; McClelland, R Scott

2016-10-01

Studies of alcohol use and sexual behavior in African populations have primarily been cross-sectional, used nonvalidated measures of alcohol use, or relied on self-reported sexual risk endpoints. Few have focused on human immunodeficiency virus (HIV)-positive women. Longitudinal data were collected from a cohort of HIV-positive Kenyan female sex workers. At enrollment and annual visits, participants were asked about past-year alcohol use using the Alcohol Use Disorders Identification Test (AUDIT). The primary endpoint was detection of prostate-specific antigen (PSA) in vaginal secretions at quarterly examinations. Associations between hazardous/harmful alcohol use (AUDIT score ≥7), PSA detection, and secondary measures of sexual risk were evaluated using generalized estimating equations with a log binomial regression model. A total of 405 women contributed 2750 vaginal samples over 606 person-years of follow-up. Hazardous/harmful alcohol use was reported at 16.6% of AUDIT assessments and was associated with higher risk of PSA detection (relative risk 1.50; 95% confidence interval, 1.11-2.01) relative to no alcohol use. This association was attenuated and no longer statistically significant, after adjusting for age, work venue, intimate partner violence, depression, and partnership status (adjusted relative risk, 1.13; 95% confidence interval, 0.82-1.56). In exploratory analyses, alcohol use was associated with self-report of unprotected sex and with sexually transmitted infection acquisition. Although hazardous/harmful alcohol use was not associated with detection of PSA in adjusted analysis, associations with secondary outcomes suggest that alcohol use is at least a marker of sexual risk behavior.

The added value of accounting for activity space when examining the association between tobacco retailer availability and smoking among young adults.

PubMed

Shareck, Martine; Kestens, Yan; Vallée, Julie; Datta, Geetanjali; Frohlich, Katherine L

2016-07-01

Despite a declining prevalence in many countries, smoking rates remain consistently high among young adults. Targeting contextual influences on smoking, such as the availability of tobacco retailers, is one promising avenue of intervention. Most studies have focused on residential or school neighbourhoods, without accounting for other settings where individuals spend time, that is, their activity space. We investigated the association between tobacco retailer availability in the residential neighbourhood and in the activity space, and smoking status. Cross-sectional baseline data from 1994 young adults (aged 18-25) participating in the Interdisciplinary Study of Inequalities in Smoking (Montreal, Canada, 2011-2012) were analysed. Residential and activity locations served to derive two measures of tobacco retailer availability: counts within 500 m buffers and proximity to the nearest retailer. Prevalence ratios for the association between each tobacco retailer measure and smoking status were estimated using log-binomial regression. Participants encountering high numbers of tobacco retailers in their residential neighbourhood, and both medium and high retailer counts in their activity space, were more likely to smoke compared to those exposed to fewer retailers. While residential proximity was not associated with smoking, we found 36% and 42% higher smoking prevalence among participants conducting activities within medium and high proximity to tobacco retailers compared to those conducting activities further from such outlets. This study adds to the sparse literature on contextual correlates of smoking among young adults, and illustrates the added value of considering individuals' activity space in contextual studies of smoking. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Respiratory Health Risks for Children Living Near a Major Railyard

PubMed Central

Soret, Sam; Knutsen, Synnove; Shavlik, David; Ghamsary, Mark; Beeson, W. Lawrence; Kim, Wonha; Montgomery, Susanne

2015-01-01

Inland southern California is a region of public health concern, especially for children, given the area’s perennially poor air quality and increasing sources of local pollution. One elementary school specifically is located only a few hundred yards from the San Bernardino Railyard, one of the busiest goods movement facilities in California, potentially increasing respiratory problems. Through ENRRICH (Environmental Railyard Research Impacting Community Health) Project, we assessed association of proximity to a major freight railyard on adverse respiratory health in schoolchildren. Respiratory screening was provided for children at two elementary schools: one near the railyard and a socio-demographically matched comparison school 7 miles away. Screening included testing for airway inflammation (FeNO), lung function (peak expiratory flow, PEF) and parent reported respiratory symptoms. Parental questionnaires collected additional information. Log-binomial and linear regression assessed associations. Children attending school near the railyard were more likely to exhibit airway obstruction with higher prevalence of abnormal PEF (<80 %): prevalence ratio (PR) = 1.59 (95 % CI 1.19–2.12). The association with inflammation was less clear. Children at the exposure school, who had lived 6 months or longer at their current address (vs. all children at that school) were more likely to have values suggesting inflammation (FeNO > 20 ppb) (PR = 1.44, 95 % CI 1.02–2.02) and present with a trend for increased adverse respiratory symptoms. Children attending school near the railyard were significantly more likely to display respiratory health challenges. Ideally these low-income, low resource communities should be supported to implement sustainable intervention strategies to promote an environment where children can live healthier and thrive. PMID:25894422

Socioecological Factors Related to Hazardous Alcohol use among Female Sex Workers in Lilongwe, Malawi: A Mixed Methods Study.

PubMed

Lancaster, Kathryn E; MacLean, Sarah A; Lungu, Thandie; Mmodzi, Pearson; Hosseinipour, Mina C; Hershow, Rebecca B; Powers, Kimberly A; Pence, Brian W; Hoffman, Irving F; Miller, William C; Go, Vivian F

2018-04-16

Alcohol use is pervasive among female sex workers (FSW) placing them at increased risk of violence and sexual risk behaviors. FSW often live and work where alcohol is highly normative. To understand the socioecological influences on hazardous alcohol use among FSW in Malawi. In 2014, 200 FSW identified through venue-based sampling in Lilongwe, Malawi, completed a quantitative behavioral survey, with a sub-sample participating in qualitative interviews. Multivariable log-binomial regression was used to identify associations between hazardous alcohol use (AUDIT score ≥ 7) and time in sex work, clients per week, unprotected sex, alcohol use with clients, and living environment. Qualitative interviews enhanced findings from quantitative data and identify emergent themes around socioecological influences on alcohol use. Over 50% reported hazardous alcohol use and lived in an alcohol-serving venue. Hazardous alcohol use was associated with sex work duration of ≥2 years (aPR: 1.30; 95%CI: 1.02,1.65) and alcohol use at last sex with a client (aPR: 1.29; 95%CI: 1.06,1.57). FSW perceived alcohol as a facilitator for sex work by reducing inhibitions and attracting clients, but acknowledged alcohol leads to violence and/or unprotected sex. Despite these risks and a motivation to reduce use, FSW feared that refusing to drink would be tantamount to turning away clients. Although FSW recognized alcohol-related risks, the norms and power dynamics of sex work perpetuated hazardous alcohol use. Multilevel interventions are needed to collectively change norms around drinking and sex work that will enable FSW to reduce alcohol consumption when engaging in their work.

Street Life and Drug Risk Behaviors Associated with Exchanging Sex Among Male Street Children in Lahore, Pakistan

PubMed Central

Towe, Vivian L.; Hasan, Salman ul; Zafar, S. Tariq; Sherman, Susan G.

2009-01-01

Background Throughout the developing world, children living on urban streets is a byproduct of economic deprivation. In Lahore, Pakistan, there are an estimated 5,000–7,000 street children. Purpose The study examined HIV risk behaviors and factors associated with exchanging sex among male street children in Lahore, Pakistan. Methods The survey was conducted from August 2003 to March 2004 among 565 registrants, ages 5–19, of Project Smile, a program that aimed to enhance the lives of street children in Lahore. We analyzed the frequency of and correlates of recent (past three months) sex exchange for money, drugs, or goods. Multivariate log-binomial regression was used to evaluate the independent effect of covariates on exchange sex. Results Approximately 40% of participants reported having exchanged sex during the past three months. In multivariate analysis, the factors associated with exchanging sex were living on the street for longer than 48 months (Prevalence Ratio [PR]=1.36, 95% Confidence Interval [CI]: 0.99–1.85), reporting ever having used drugs (PR=1.87, 1.10–3.16), cutting one’s self (PR=1.66, 95% CI: 1.26–2.19), and having heard of HIV/AIDS (PR=1.36, 95% CI: 1.03–1.80) after adjusting for demographic and street life variables. Conclusions We found high rates of sex exchange among a sample of street children in Lahore, Pakistan. The finding that children who have heard about HIV/AIDS are more likely to exchange sex suggests that children at HIV risk talk about HIV, but accuracy of their conversations is unclear. Street children in Pakistan are in great need of HIV education and safe alternatives for generating income. PMID:19237107

Occupational solvent exposure and cognition

PubMed Central

Sabbath, E.L.; Glymour, M.M.; Berr, C.; Singh-Manoux, A.; Zins, M.; Goldberg, M.

2012-01-01

Objective: Chronic occupational solvent exposure is associated with long-term cognitive deficits. Cognitive reserve may protect solvent-exposed workers from cognitive impairment. We tested whether the association between chronic solvent exposure and cognition varied by educational attainment, a proxy for cognitive reserve. Methods: Data were drawn from a prospective cohort of French national gas and electricity (GAZEL) employees (n = 4,134). Lifetime exposure to 4 solvent types (chlorinated solvents, petroleum solvents, benzene, and nonbenzene aromatic solvents) was assessed using a validated job-exposure matrix. Education was dichotomized at less than secondary school or below. Cognitive impairment was defined as scoring below the 25th percentile on the Digit Symbol Substitution Test at mean age 59 (SD 2.8; 88% of participants were retired at testing). Log-binomial regression was used to model risk ratios (RRs) for poor cognition as predicted by solvent exposure, stratified by education and adjusted for sociodemographic and behavioral factors. Results: Solvent exposure rates were higher among less-educated patients. Within this group, there was a dose-response relationship between lifetime exposure to each solvent type and RR for poor cognition (e.g., for high exposure to benzene, RR = 1.24, 95% confidence interval 1.09–1.41), with significant linear trends (p < 0.05) in 3 out of 4 solvent types. Recency of solvent exposure also predicted worse cognition among less-educated patients. Among those with secondary education or higher, there was no significant or near-significant relationship between any quantification of solvent exposure and cognition. Conclusions: Solvent exposure is associated with poor cognition only among less-educated individuals. Higher cognitive reserve in the more-educated group may explain this finding. PMID:22641403

Factors across the life course predict women's change in smoking behaviour during pregnancy and in midlife: results from the National Child Development Study.

PubMed

Schoenaker, Danielle A J M; Ploubidis, George B; Goodman, Alissa; Mishra, Gita D

2017-12-01

Tobacco smoking before, during and after pregnancy remains one of the few preventable factors associated with poor health outcomes for mothers and their children. We investigate predictors across the life course for change in smoking behaviour during pregnancy and whether this change predicts smoking status in midlife. Data were from the National Child Development Study (1958 British birth cohort). We included female cohort members who reported a first pregnancy up to age 33 years. Among 1468 women who smoked before pregnancy, we examined predictors reported in childhood (age 11 years), adolescence (age 16 years) and early adulthood (age 23 years) of change in smoking behaviour from 12 months before to during pregnancy using log-binomial regression. The association between change in smoking behaviour during pregnancy and smoking status in midlife (age 55 years) was examined while adjusting for predictors across the life course. Among prepregnancy smokers (39%), 26% reduced and 35% quit smoking during pregnancy. Parental smoking and lower social class during childhood, and early adulthood lower social class, depression, early smoking initiation, high smoking intensity, living with a smoker, no pregnancy planning and early motherhood were associated with lower probability of smoking reduction or cessation in pregnancy. Compared with women who smoked before and during pregnancy, women who reduced or quit were two times more likely to be non-smoker at age 55 years (95% CI 1.76 to 2.20). Findings from this population-based birth cohort study lend support for smoking cessation strategies that target those at risk at various stages across the life course. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Age-specific prevalence of human papilloma virus infection among Nigerian women.

PubMed

Akarolo-Anthony, Sally N; Famooto, Ayo O; Dareng, Eileen O; Olaniyan, Olayinka B; Offiong, Richard; Wheeler, Cosette M; Adebamowo, Clement A

2014-06-27

Inconsistent trends in HPV prevalence by age have been described in Africa. We examined the age prevalence pattern and distribution of 37 HPV-DNA types among urban Nigerian women. The study population was a sample of 278 women who presented to cervical cancer screening programs in Abuja, Nigeria, between April and August 2012. Using a nurse administered questionnaire, information on demographic characteristics and risk factors of cervical cancer was collected and samples of cervical exfoliated cells were obtained from all participants. Roche Linear Array HPV Genotyping Test® was used to characterize prevalent HPV and log-binomial regression models were used to examine the association between potential correlates and the prevalence of HPV infection. The mean age (SD) of the women enrolled was 38 (8) years. The overall prevalence of HPV was 37%. HPV 35 was the most prevalent HPV type in the study population. Among women age ≤ 30 years, 52% had HPV infection compared to 23% of those women who were older than 45 years (p = 0.006). We observed a significant linear association between age and the prevalence of HPV infections. The prevalence ratio (PR) and 95% confidence interval (CI) was 2.26 (1.17, 4.34) for any HPV infection, 3.83 (1.23, 11.94) for Group 1 HPV (definite carcinogens), and 2.19 (0.99, 4.84) for Group 2a or 2b HPV (probable or possible carcinogens) types, among women aged 18-30 years, compared to women who were older than 45 years. The prevalence of HPV infection was highest among younger women and decreased steadily with age among this population of urban Nigerian women.

Measures of economic advantage associated with HPV-positive head and neck cancers among non-Hispanic black and white males identified through the National Cancer Database

PubMed Central

Peterson, Caryn E.; Khosla, Shaveta; Jefferson, Gina D.; Davis, Faith G.; Fitzgibbon, Marian L.; Freels, Sally; Johnson, Timothy P.; Hoskins, Kent; Joslin, Charlotte E.

2018-01-01

Background National trends show dramatic increases in the incidence of HPV-related head and neck squamous cell carcinomas (HNSCCs) among black and white males. Using cases identified through the National Cancer Data Base, we assessed factors associated with HPV 16- or 16/18 positive HNSCCs among non-Hispanic black and white males diagnosed in the U.S. between 2009 and 2013. Methods This sample included 21,524 HNSCCs with known HPV status. Adjusted relative risks (RRs) and 95% confidence intervals (CIs) were estimated using log-binomial regression. Results Compared to those with HPV-negative tumors, male patients diagnosed with HPV-positive HNSCCs were non-Hispanic white, younger at diagnosis, lived in zip-code areas with higher median household income and higher educational attainment, had private health insurance and no reported comorbidities at diagnosis. Although the risk of HPV-positive HNSCCs increased with measures of higher area-level socioeconomic status, the effect was stronger for non-Hispanic black males (RRAdjusted = 1.76, 95% CI 1.49–2.09) than for whites (RRAdjusted = 1.12, 95% CI 1.08–1.16). The peak age for diagnosis of HPV-positive HNSCCs occurred in those diagnosed at 45–49 years (RRAdjusted = 1.57, 95% CI 1.42–1.73). Oropharyngeal tumors were strongly associated with HPV-positivity (RRAdjusted = 4.32, 95% CI 4.03–4.63). In the analysis restricted to oropharyngeal anatomic sites, similar patterns persisted. Conclusion In our analysis, measures of economic advantage were associated with an increased risk of HPV-positive HNSCCs. In order to develop effective interventions, greater understanding of the risk factors for HPV-positive HNSCCs is needed among both high-risk males and their healthcare providers. PMID:28282541

Risk of fentanyl-involved overdose among those with past year incarceration: Findings from a recent outbreak in 2014 and 2015.

PubMed

Brinkley-Rubinstein, Lauren; Macmadu, Alexandria; Marshall, Brandon D L; Heise, Andrew; Ranapurwala, Shabbar I; Rich, Josiah D; Green, Traci C

2018-04-01

Overdose is the leading cause of unintentional injury-related death. Rhode Island (RI) has the highest rate of illicit drug use nationally and the 5th highest overdose mortality rate. RI has experienced an outbreak of fentanyl-related overdoses. In incarcerated populations, risk of overdose is greatly elevated. However, little is known about fentanyl-related overdose post-release. In the current analyses, we identify changes in fentanyl-related fatal overdose among those who died in 2014 and 2015 who were incarcerated in the year before death. We linked data from the RI Office of the Medical Examiner with records from the RI Department of Corrections. We calculated risk ratios and 95% confidence intervals using log-binomial regression to compare risk of fentanyl-involved overdose death. We also compared median time to death since release, median sentence length, and median number of incarcerations in 2014 and 2015. Results indicate that the risk of dying of a fentanyl-related overdose increased (RR: 1.99 (95% CI: 1.11-3.57, p = 0.014)) from 2014 to 2015 among those with past year incarceration. This study is one of the first to describe fentanyl-related fatal overdose among those with past year incarceration. In 2015 the median sentence was longer among those with a fentanyl-related overdose death and the median time from release to death among all who had past year incarceration extended past 90 days. Access to medications for addiction treatment, overdose education, and naloxone should be available during community re-entry and extended beyond the early post-release period. Copyright © 2018. Published by Elsevier B.V.

Access to care in the Baltic States: did crisis have an impact?

PubMed

Karanikolos, Marina; Gordeev, Vladimir S; Mackenbach, Johan P; McKee, Martin

2016-04-01

In 2009, brief but deep economic crisis profoundly affected the three Baltic States: Estonia, Latvia and Lithuania. In response, all three countries adopted severe austerity measures with the shared goal of containing rising deficits, but employing different methods. In this article, we analyze the impact of the economic crisis and post-crisis austerity measures on health systems and access to medical services in the three countries. We use the EU-SILC data to analyze trends in unmet medical need in 2005-2012, and apply log-binomial regression to calculate the risk of unmet medical need in the pre- and post- crisis period. Between 2009 and 2012 unmet need has increased significantly in Latvia (OR: 1.24, 95% confidence interval (CI): 1.15-1.34) and Estonia (OR: 1.98, 95% CI: 1.72-2.27), but not Lithuania (OR: 0.84. 95% CI: 0.69-1.04). The main drivers of increased unmet need were inability to afford care in Latvia and long waiting lists in Estonia. The impact of the crisis on access to care in the three countries varied, as did the austerity measures affecting their health systems. Estonia and Latvia experienced worsening access to care, largely exacerbating already existing barriers. The example of Lithuania suggests that deterioration in access is not inevitable, once health policies prioritise maintenance and availability of existing services, or if there is room for reducing existing inefficiencies. Moreover, better financial preparedness of health systems in Estonia and Lithuania achieved some protection of the population from increasing unmet need due to the rising cost of medical care. © The Author 2015. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

Green Space Visits among Adolescents: Frequency and Predictors in the PIAMA Birth Cohort Study.

PubMed

Bloemsma, Lizan D; Gehring, Ulrike; Klompmaker, Jochem O; Hoek, Gerard; Janssen, Nicole A H; Smit, Henriëtte A; Vonk, Judith M; Brunekreef, Bert; Lebret, Erik; Wijga, Alet H

2018-04-30

Green space may influence health through several pathways, for example, increased physical activity, enhanced social cohesion, reduced stress, and improved air quality. For green space to increase physical activity and social cohesion, spending time in green spaces is likely to be important. We examined whether adolescents visit green spaces and for what purposes. Furthermore, we assessed the predictors of green space visits. In this cross-sectional study, data for 1911 participants of the Dutch PIAMA (Prevention and Incidence of Asthma and Mite Allergy) birth cohort were analyzed. At age 17, adolescents reported how often they visited green spaces for physical activities, social activities, relaxation, and to experience nature and quietness. We assessed the predictors of green space visits altogether and for different purposes by log-binomial regression. Fifty-three percent of the adolescents visited green spaces at least once a week in summer, mostly for physical and social activities. Adolescents reporting that a green environment was (very) important to them visited green spaces most frequently {adjusted prevalence ratio (PR) [95% confidence interval (CI)] very vs. not important: 6.84 (5.10, 9.17) for physical activities and 4.76 (3.72, 6.09) for social activities}. Boys and adolescents with highly educated fathers visited green spaces more often for physical and social activities. Adolescents who own a dog visited green spaces more often to experience nature and quietness. Green space visits were not associated with the objectively measured quantity of residential green space, i.e., the average normalized difference vegetation index (NDVI) and percentages of urban, agricultural, and natural green space in circular buffers around the adolescents' homes. Subjective variables are stronger predictors of green space visits in adolescents than the objectively measured quantity of residential green space. https://doi.org/10.1289/EHP2429.

Preterm birth time trends in Europe: a study of 19 countries.

PubMed

Zeitlin, J; Szamotulska, K; Drewniak, N; Mohangoo, A D; Chalmers, J; Sakkeus, L; Irgens, L; Gatt, M; Gissler, M; Blondel, B

2013-10-01

To investigate time trends in preterm birth in Europe by multiplicity, gestational age, and onset of delivery. Analysis of aggregate data from routine sources. Nineteen European countries. Live births in 1996, 2000, 2004, and 2008. Annual risk ratios of preterm birth in each country were estimated with year as a continuous variable for all births and by subgroup using log-binomial regression models. Overall preterm birth rate and rate by multiplicity, gestational age group, and spontaneous versus non-spontaneous (induced or prelabour caesarean section) onset of labour. Preterm birth rates rose in most countries, but the magnitude of these increases varied. Rises in the multiple birth rate as well as in the preterm birth rate for multiple births contributed to increases in the overall preterm birth rate. About half of countries experienced no change or decreases in the rates of singleton preterm birth. Where preterm birth rates rose, increases were no more prominent at 35-36 weeks of gestation than at 32-34 weeks of gestation. Variable trends were observed for spontaneous and non-spontaneous preterm births in the 13 countries with mode of onset data; increases were not solely attributed to non-spontaneous preterm births. There was a wide variation in preterm birth trends in European countries. Many countries maintained or reduced rates of singleton preterm birth over the past 15 years, challenging a widespread belief that rising rates are the norm. Understanding these cross-country differences could inform strategies for the prevention of preterm birth. © 2013 The Authors. BJOG: An International Journal of Obstetrics & Gynaecology published by John Wiley and Sons on behalf of the Royal College of Obstetricians and Gynaecologists.

Determinants of participation in prostate cancer screening: A simple analytical framework to account for healthy-user bias

PubMed Central

Tabuchi, Takahiro; Nakayama, Tomio; Fukushima, Wakaba; Matsunaga, Ichiro; Ohfuji, Satoko; Kondo, Kyoko; Kawano, Eiji; Fukuhara, Hiroyuki; Ito, Yuri; Oshima, Akira

2015-01-01

In Japan at present, fecal occult blood testing (FOBT) is recommended for cancer screening while routine population-based prostate-specific antigen (PSA) screening is not. In future it may be necessary to increase participation in the former and decrease it in the latter. Our objectives were to explore determinants of PSA-screening participation while simultaneously taking into account factors associated with FOBT. Data were gathered from a cross-sectional study conducted with random sampling of 6191 adults in Osaka city in 2011. Of 3244 subjects (return rate 52.4%), 936 men aged 40–64 years were analyzed using log-binomial regression to explore factors related to PSA-screening participation within 1 year. Only responders for cancer screening, defined as men who participated in either FOBT or PSA-testing, were used as main study subjects. Men who were older (prevalence ratio [PR] [95% confidence interval (CI)] = 2.17 [1.43, 3.28] for 60–64 years compared with 40–49 years), had technical or junior college education (PR [95% CI] = 1.76 [1.19, 2.59] compared with men with high school or less) and followed doctors' recommendations (PR [95% CI] = 1.50 [1.00, 2.26]) were significantly more likely to have PSA-screening after multiple variable adjustment among cancer-screening responders. Attenuation in PR of hypothesized common factors was observed among cancer-screening responders compared with the usual approach (among total subjects). Using the analytical framework to account for healthy-user bias, we found three factors related to participation in PSA-screening with attenuated association of common factors. This approach may provide a more sophisticated interpretation of participation in various screenings with different levels of recommendation. PMID:25456306

Determinants of High-School Dropout: A Longitudinal Study in a Deprived Area of Japan.

PubMed

Tabuchi, Takahiro; Fujihara, Sho; Shinozaki, Tomohiro; Fukuhara, Hiroyuki

2018-05-19

Our objective in this study was to find determinants of high-school dropout in a deprived area of Japan using longitudinal data, including socio-demographic and junior high school-period information. We followed 695 students who graduated the junior high school located in a deprived area of Japan between 2002 and 2010 for 3 years after graduation (614 students: follow-up rate, 88.3%). Multivariable log-binomial regression models were used to calculate the prevalence ratios (PRs) for high-school dropout, using multiple imputation (MI) to account for non-response at follow-up. The MI model estimated that 18.7% of students dropped out of high school in approximately 3 years. In the covariates-adjusted model, three factors were significantly associated with high-school dropout: ≥10 days of tardy arrival in junior high school (PR 6.44; 95% confidence interval [CI], 1.69-24.6 for "10-29 days of tardy arrival" and PR 8.01; 95% CI, 2.05-31.3 for "≥30 days of tardy arrival" compared with "0 day of tardy arrival"), daily smoking (PR 2.01; 95% CI, 1.41-2.86) and severe problems, such as abuse and neglect (PR 1.66; 95% CI, 1.16-2.39). Among students with ≥30 days of tardy arrival in addition to daily smoking or experience of severe problems, ≥50% high-school dropout rates were observed. Three determinants of high-school dropout were found: smoking, tardy arrival, and experience of severe problems. These factors were correlated and should be treated as warning signs of complex behavioral and academic problems. Parents, educators, and policy makers should work together to implement effective strategies to prevent school dropout.

Factors Influencing Early Feeding of Foods and Drinks Containing Free Sugars-A Birth Cohort Study.

PubMed

Ha, Diep H; Do, Loc G; Spencer, Andrew John; Thomson, William Murray; Golley, Rebecca K; Rugg-Gunn, Andrew J; Levy, Steven M; Scott, Jane A

2017-10-23

Early feeding of free sugars to young children can increase the preference for sweetness and the risk of consuming a cariogenic diet high in free sugars later in life. This study aimed to investigate early life factors influencing early introduction of foods/drinks containing free sugars. Data from an ongoing population-based birth cohort study in Australia were used. Mothers of newborn children completed questionnaires at birth and subsequently at ages 3, 6, 12, and 24 months. The outcome was reported feeding (Yes/No) at age 6-9 months of common foods/drinks sources of free sugars (hereafter referred as foods/drinks with free sugars). Household income quartiles, mother's sugar-sweetened beverage (SSB) consumption, and other maternal factors were exposure variables. Analysis was conducted progressively from bivariate to multivariable log-binomial regression with robust standard error estimation to calculate prevalence ratios (PR) of being fed foods/drinks with free sugars at an early age (by 6-9 months). Models for both complete cases and with multiple imputations (MI) for missing data were generated. Of 1479 mother/child dyads, 21% of children had been fed foods/drinks with free sugars. There was a strong income gradient and a significant positive association with maternal SSB consumption. In the complete-case model, income Q1 and Q2 had PRs of 1.9 (1.2-3.1) and 1.8 (1.2-2.6) against Q4, respectively. The PR for mothers ingesting SSB everyday was 1.6 (1.2-2.3). The PR for children who had been breastfed to at least three months was 0.6 (0.5-0.8). Similar findings were observed in the MI model. Household income at birth and maternal behaviours were significant determinants of early feeding of foods/drinks with free sugars.

Intimate partner violence and maternal educational practice

PubMed Central

da Silva, Josianne Maria Mattos; Lima, Marília de Carvalho; Ludermir, Ana Bernarda

2017-01-01

ABSTRACT OBJECTIVE The objective of this study is to analyze the association between intimate partner violence against women and maternal educational practice directed to children at the beginning of formal education. METHODS This is a cross-sectional study, carried out between 2013 and 2014, with 631 mother/child pairs, registered in the Family Health Strategy of the Health District II of the city of Recife, State of Pernambuco, Brazil. It integrates a prospective cohort study designed to investigate the consequences of exposure to intimate partner violence in relation to the child who was born between 2005 and 2006. The maternal educational practice has been assessed by the Parent-Child Conflict Tactics Scale and the intimate partner violence by a questionnaire adapted from the Multi-Country Study on Women’s Health and Domestic Violence of the World Health Organization. Intimate partner violence referred to the last 12 months and was defined by specific acts of psychological, physical, and sexual violence inflicted to women by the partner. The crude and adjusted prevalence ratios were estimated for the association studied, using log-binomial regression. RESULTS The prevalence of intimate partner violence was 24.4%, and violent maternal educational practice was 93.8%. The use of non-violent discipline was mentioned by 97.6% of the women, coexisting with violent strategies of discipline. Children whose mothers reported intimate partner violence presented a higher chance of suffering psychological aggression (PR = 2.2; 95%CI 1.0–4.7). CONCLUSIONS The violence suffered by the mother interferes in the parental education. The findings show high prevalence of violent maternal educational practice, pointing to the need for interventions that minimize the damage of violence in women and children. PMID:28423138

Vaccine effectiveness of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine during a pertussis outbreak in Maine.

PubMed

Terranella, Andrew; Rea, Vicki; Griffith, Matthew; Manning, Susan; Sears, Steven; Farmer, Ann; Martin, Stacey; Patel, Manisha

2016-05-11

Multiple school-associated pertussis outbreaks were reported in Maine from 2010 to 2011. These outbreaks were associated with an overall increase in pertussis cases statewide. Waning of protection in students recently vaccinated with tetanus, diphtheria, and acellular pertussis (Tdap) has been implicated in the increase in reported rates of pertussis nationally. We conducted a retrospective cohort study to evaluate Tdap vaccine effectiveness (VE) among students aged 11-19 years in two schools reporting outbreaks in 2011. All pertussis cases reported from August through November, 2011 at the two schools were included. Vaccination history was verified using provider information, state vaccine registry data, and parental verification. Attack rates (AR) were calculated. VE and duration of protection was calculated as VE=1-(ARvaccinated/ARunvaccinated)×100% using a log binomial regression model. Of 416 students enrolled, 314 were included in the analyses. Twenty-nine cases collectively in Schools A and B. Tdap coverage was 65% at School A and 42% at School B before the start of the outbreak. Among students enrolled in the study, attack rates were 11.9% and 7.7% at Schools A and B, respectively. Overall VE was 68.5% (95% confidence interval (CI) 37.7-86.2). VE was 70.4% (95% CI 17.5-89.4) for School A and 65.2% (95% CI -19.2 to 89.9) for School B. VE <2 years versus ≥2 years from outbreak onset was not significantly different. Tdap was moderately effective in preventing disease among vaccinated students. Vaccine coverage of 65% or less was suboptimal and might contribute to outbreaks. Waning VE was not demonstrated. Increased vaccination coverage rates as well as further evaluation of the role of acellular vaccine on VE is needed. Published by Elsevier Ltd.

Periconceptional Folic Acid Supplementation and Infant Risk of Congenital Heart Defects in Norway 1999-2009.

PubMed

Leirgul, Elisabeth; Gildestad, Trude; Nilsen, Roy Miodini; Fomina, Tatiana; Brodwall, Kristoffer; Greve, Gottfried; Vollset, Stein Emil; Holmstrøm, Henrik; Tell, Grethe S; Øyen, Nina

2015-09-01

The birth prevalence of congenital heart defects (CHDs) has decreased in Canada and Europe. Recommended intake of folic acid in pregnancy is a suggestive risk-reducing factor for CHDs. We investigated the association between periconceptional intake of folic acid supplements and infant risk of CHDs. Information on maternal intake of folic acid supplements before and during pregnancy in the Medical Birth Registry of Norway 1999-2009 was updated with information on CHD diagnoses from national health registers and the Cardiovascular Diseases in Norway Project. The association between folic acid intake and infant risk of CHD was estimated as relative risk (RR) with binomial log linear regression. Among 517 784 non-chromosomal singleton births, 6200 children were identified with CHD and 1153 with severe CHD. For all births, 18.4% of the mothers initiated folic acid supplements before pregnancy and 31.6% during pregnancy. The adjusted RR for severe CHD was 0.99 [95% confidence interval [CI] 0.86, 1.13] comparing periconceptional intake of folic acid with no intake. Specifically, RR for conotruncal defects was 0.99 [95% CI 0.80, 1.22], atrioventricular septal defects 1.19 [95% CI 0.78, 1.81], left ventricular outflow tract obstructions 1.02 [95% CI 0.78, 1.32], and right ventricular outflow tract obstructions 0.97 [95% CI 0.72, 1.29]. Birth prevalence of septal defects was higher in the group exposed to folic acid supplements with RR 1.19 [95% CI 1.10, 1.30]. Periconceptional folic acid supplement use showed no association with severe CHDs in the newborn. An unexpected association with an increased risk of septal defects warrants further investigation. © 2015 The Authors. Paediatric and Perinatal Epidemiology Published by John Wiley & Sons Ltd.

The relationship between adiposity-associated inflammation and coronary artery and abdominal aortic calcium differs by strata of central adiposity: The Multi-Ethnic Study of Atherosclerosis (MESA).

PubMed

Hughes-Austin, Jan M; Wassel, Christina L; Jiménez, Jessica; Criqui, Michael H; Ix, Joachim H; Rasmussen-Torvik, Laura J; Budoff, Matthew J; Jenny, Nancy S; Allison, Matthew A

2014-08-01

Adipokines regulate metabolic processes linked to coronary artery (CAC) and abdominal aorta calcification (AAC). Because adipokine and other adiposity-associated inflammatory marker (AAIM) secretions differ between visceral and subcutaneous adipose tissue, we hypothesized that central adiposity modifies associations between AAIMs and CAC and AAC. We evaluated 1878 MESA participants with complete measures of AAIMs, anthropometry, CAC, and AAC. Associations of AAIMs with CAC and AAC prevalence and severity were analyzed per standard deviation of predictors (SD) using log binomial and linear regression models. The waist-to-hip ratio (WHR) was dichotomized at median WHR values based on sex/ethnicity. CAC and AAC prevalence were defined as any calcium (Agatston score >0). Severity was defined as ln (Agatston score). Analyses examined interactions with WHR and were adjusted for traditional cardiovascular disease risk factors. Each SD higher interleukin-6 (IL-6), fibrinogen and CRP was associated with 5% higher CAC prevalence; and each SD higher IL-6 and fibrinogen was associated with 4% higher AAC prevalence. Associations of IL-6 and fibrinogen with CAC severity, but not CAC prevalence, were significantly different among WHR strata. Median-and-above WHR: each SD higher IL-6 was associated with 24.8% higher CAC severity. Below-median WHR: no association (p interaction =0.012). Median-and-above WHR: each SD higher fibrinogen was associated with 19.6% higher CAC severity. Below-median WHR: no association (p interaction =0.034). Adiponectin, leptin, resistin, and tumor necrosis factor-alpha were not associated with CAC or AAC prevalence or severity. These results support findings that adiposity-associated inflammation is associated with arterial calcification, and further add that central adiposity may modify this association. © The Author(s) 2014.

Correlates of Lifetime History of Purchasing Sex Services by Men in Saint Petersburg and Leningrad Oblast, Russia.

PubMed

Girchenko, P; Ompad, D C; Kulchynska, R; Bikmukhametov, D; Dugin, S; Gensburg, L

2015-12-01

Commercial sex workers (CSWs) in the Russian Federation are at high risk of HIV infection and transmission as a result of unsafe sexual and injecting behaviors. Their clients might be at increased risk of acquiring HIV; however, little is known about the population of men purchasing sex services. This study aims to investigate factors associated with a history of purchasing sex services by men in Saint Petersburg and Leningrad Oblast, Russian Federation. Data were collected as part of a cross-sectional study offering free anonymous rapid HIV testing in Saint Petersburg and Leningrad Oblast in 2014; in total, 3565 men aged 18 years and older provided information about their behaviors associated with risk of acquiring HIV during face-to-face interviews. Prevalence of CSW use in our study was 23.9%. Multivariable analyses using log-binomial regression were stratified by self-reported HIV testing during the 12 months preceding the study interview. In both strata, older age, multiple sex partners, and a history of sex with an injection drug user (IDU) were associated with an elevated prevalence ratio (PR) for history of purchasing sex services, although the strength of the association differed by strata. Among men who reported recent HIV testing, condom use (PR = 1.22, 90% confidence interval (CI) 1.0, 1.48) was associated with a history of purchasing sex services, and among men who did not report recent HIV testing, having a consistent sex partner was associated with purchasing sex services (PR = 1.23, 90% CI 1.1, 1.37). The high prevalence of CSW service use and associations found in this study raise serious concerns about potential for sexual HIV transmission and should be investigated more closely.

Short Operative Duration and Surgical Site Infection Risk in Hip and Knee Arthroplasty Procedures

PubMed Central

Dicks, Kristen V.; Baker, Arthur W.; Durkin, Michael J.; Anderson, Deverick J.; Moehring, Rebekah W.; Chen, Luke F.; Sexton, Daniel J.; Weber, David J.; Lewis, Sarah S.

2016-01-01

OBJECTIVE To determine the association (1) between shorter operative duration and surgical site infection (SSI) and (2) between surgeon median operative duration and SSI risk among first-time hip and knee arthroplasties. DESIGN Retrospective cohort study SETTING A total of 43 community hospitals located in the southeastern United States. PATIENTS Adults who developed SSIs according to National Healthcare Safety Network criteria within 365 days of first-time knee or hip arthroplasties performed between January 1, 2008 and December 31, 2012. METHODS Log-binomial regression models estimated the association (1) between operative duration and SSI outcome and (2) between surgeon median operative duration and SSI outcome. Hip and knee arthroplasties were evaluated in separate models. Each model was adjusted for American Society of Anesthesiology score and patient age. RESULTS A total of 25,531 hip arthroplasties and 42,187 knee arthroplasties were included in the study. The risk of SSI in knee arthroplasties with an operative duration shorter than the 25th percentile was 0.40 times the risk of SSI in knee arthroplasties with an operative duration between the 25th and 75th percentile (risk ratio [RR], 0.40; 95% confidence interval [CI], 0.38–0.56; P <.01). Short operative duration did not demonstrate significant association with SSI for hip arthroplasties (RR, 1.04; 95% CI, 0.79–1.37; P =.36). Knee arthroplasty surgeons with shorter median operative durations had a lower risk of SSI than surgeons with typical median operative durations (RR, 0.52; 95% CI, 0.43–0.64; P <.01). CONCLUSIONS Short operative durations were not associated with a higher SSI risk for knee or hip arthroplasty procedures in our analysis. PMID:26391277

Air Quality Awareness Among U.S. Adults With Respiratory and Heart Disease.

PubMed

Mirabelli, Maria C; Boehmer, Tegan K; Damon, Scott A; Sircar, Kanta D; Wall, Hilary K; Yip, Fuyuen Y; Zahran, Hatice S; Garbe, Paul L

2018-05-01

Poor air quality affects respiratory and cardiovascular health. Information about health risks associated with outdoor air quality is communicated to the public using air quality alerts. This study was conducted to assess associations of existing respiratory and heart disease with three aspects of air quality awareness: awareness of air quality alerts, discussing with a health professional strategies to reduce air pollution exposure, and avoiding busy roads to reduce air pollution exposure when walking, biking, or exercising outdoors. During 2014-2016, a total of 12,599 U.S. adults participated in summer waves of the ConsumerStyles surveys and self-reported asthma, emphysema/chronic obstructive pulmonary disease, heart disease, and each aspect of air quality awareness. In 2017, associations between each health condition and air quality awareness were estimated using log binomial and multinomial regression. Overall, 49% of respondents were aware of air quality alerts, 3% discussed with a health professional strategies to reduce air pollution exposure, and 27% always/usually avoided busy roads to reduce air pollution exposure. Asthma was associated with increased prevalence of awareness of air quality alerts (prevalence ratio=1.11, 95% CI=1.04, 1.20), discussing with a health professional (prevalence ratio=4.88, 95% CI=3.74, 6.37), and always/usually avoiding busy roads to reduce air pollution exposure (prevalence ratio=1.13, 95% CI=1.01, 1.27). Heart disease was not associated with air quality awareness. Existing respiratory disease, but not heart disease, was associated with increased air quality awareness. These findings reveal important opportunities to raise awareness of air quality alerts and behavior changes aimed at reducing air pollution exposure among adults at risk of exacerbating respiratory and heart diseases. Published by Elsevier Inc.

Plurality of Birth and Infant Mortality Due to External Causes in the United States, 2000-2010.

PubMed

Ahrens, Katherine A; Thoma, Marie E; Rossen, Lauren M; Warner, Margaret; Simon, Alan E

2017-03-01

Risk of death during the first year of life due to external causes, such as unintentional injury and homicide, may be higher among twins and higher-order multiples than among singletons in the United States. We used national birth cohort linked birth-infant death data (2000-2010) to evaluate the risk of infant mortality due to external causes in multiples versus singletons in the United States. Risk of death from external causes during the study period was 3.6 per 10,000 live births in singletons and 5.1 per 10,000 live births in multiples. Using log-binomial regression, the corresponding unadjusted risk ratio was 1.40 (95% confidence interval (CI): 1.30, 1.50). After adjustment for maternal age, marital status, race/ethnicity, and education, the risk ratio was 1.68 (95% CI: 1.56, 1.81). Infant deaths due to external causes were most likely to occur between 2 and 7 months of age. Applying inverse probability weighting and assuming a hypothetical intervention where no infants were low birth weight, the adjusted controlled direct effect of plurality on infant mortality due to external causes was 1.64 (95% CI: 1.39, 1.97). Twins and higher-order multiples were at greater risk of infant mortality due to external causes, particularly between 2 and 7 months of age, and this risk appeared to be mediated largely by factors other than low-birth-weight status. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Prescription patterns of analgesics in the last 3 months of life: a retrospective analysis of 10202 lung cancer patients

PubMed Central

Gao, W; Gulliford, M; Higginson, I J

2011-01-01

Background: To describe the prescription patterns of analgesics during the last 3 months of life in lung cancer and to determine the associated factors. Methods: Data on lung cancer patients (N=10 202) who died during 2000–2008 were extracted from the General Practice Research Database (GPRD). This database records prescriptions of patients received from UK general practices (GP), but not those from non-GP routes. Prescription prevalences were estimated. The associated factors were investigated using log-binomial regression. Results: The overall prescription prevalences were 50.4% (95% confidence interval (CI): 49.4–51.4%) for level 1 (e.g., paracetamol), 34.1% (95% CI: 33.2–35.0%) for level 2 (weak opioids), and 55.5 % (95% CI: 54.5–56.4%) for level 3 analgesics (strong opioids). Prescription prevalence of analgesics of all levels showed an increasing trend over the period 2000–2008 (annual increases range: 1.1–1.5%) but a decreasing trend with age (average decrease per group range: −5.8 to −1.8%). Patients in the older age groups were less likely to be prescribed level 3 analgesics than those in the younger age groups (PR‘90+' vs ‘<50'=0.55 (95% CI: 0.45–0.67); PR‘80−89' vs ‘<50'=0.73 (95% CI: 0.66–0.79); PR‘70−79' vs ‘<50'=0.84 (95% CI: 0.77–0.90)). Conclusion: Analgesics have been increasingly prescribed in lung cancer. However, analgesics, especially at level 3, were relatively under-prescribed to people older than 70 years, warranting further investigation. PMID:21540860

A Prospective Study of Back Pain and Risk of Falls Among Older Community-dwelling Women

PubMed Central

Litwack-Harrison, Stephanie; Cawthon, Peggy M.; Kado, Deborah M.; Deyo, Richard A.; Makris, Una E.; Carlson, Hans L.; Nevitt, Michael C.

2016-01-01

Background. Back pain and falls are common health conditions among older U.S. women. The extent to which back pain is an independent risk factor for falls has not been established. Methods. We conducted a prospective study among 6,841 community-dwelling U.S. women at least 65 years of age from the Study of Osteoporotic Fractures (SOF). Baseline questionnaires inquired about any back pain, pain severity, and frequency in the past year. During 1 year of follow-up, falls were summed from self-reports obtained every 4 months. Two outcomes were studied: recurrent falls (≥2 falls) and any fall (≥1 fall). Associations of back pain and each fall outcome were estimated with risk ratios (RRs) and 95% confidence intervals (CIs) from multivariable log-binomial regression. Adjustments were made for age, education, smoking status, fainting history, hip pain, stroke history, vertebral fracture, and Geriatric Depression Scale. Results. Most (61%) women reported any back pain. During follow-up, 10% had recurrent falls and 26% fell at least once. Any back pain relative to no back pain was associated with a 50% increased risk of recurrent falls (multivariable RR = 1.5, 95% CI: 1.3, 1.8). Multivariable RRs for recurrent falls were significantly elevated for all back pain symptoms, ranging from 1.4 (95% CI: 1.1, 1.8) for mild back pain to 1.8 (95% CI: 1.4, 2.3) for activity-limiting back pain. RRs of any fall were also significantly increased albeit smaller than those for recurrent falls. Conclusions. Older community-dwelling women with a recent history of back pain are at increased risk for falls. PMID:26757988

Low maternal 25-hydroxyvitamin D concentration increases the risk of severe and mild preeclampsia.

PubMed

Baca, Katharyn M; Simhan, Hyagriv N; Platt, Robert W; Bodnar, Lisa M

2016-12-01

The objective of this case-cohort study was to evaluate the relationship between maternal 25-hydroxyvitamin D (25(OH)D) concentration and preeclampsia overall and by severity. From an eligible cohort of 12,861 women who had serum banked from aneuploidy screening in Pittsburgh, Pennsylvania from 1999 to 2010, we randomly sampled a subcohort of 2327 pregnancies and all remaining preeclampsia cases (n = 650 cases). Preeclampsia (defined as new-onset hypertension and proteinuria) and its mild and severe forms were identified using ICD-9 codes. Maternal serum collected at 20 weeks or less gestation was measured for 25(OH)D. We used log-binomial regression with restricted cubic splines to estimate the association between 25(OH)D and preeclampsia after adjusting for confounders. Approximately 21% of the randomly selected sample had 25(OH)D less than 50 nmol per L. We found that the adjusted risk of preeclampsia declined as serum 25(OH)D increased to 50 nmol per L and then plateaued (test of nonlinearity P < .05). The adjusted preeclampsia risk ratios (95% confidence intervals) for 25(OH)D less than 25 nmol per L, 25 to 49.9 nmol per L, and 50 to 74.9 nmol per L were 2.4 (1.2-4.8), 1.1 (0.69-1.7), and 1.3 (0.89-1.8), respectively, compared with those with 25(OH)D 75 nmol per L and over. Similar associations were observed with severe and mild preeclampsia. Vitamin D deficiency increases risks of severe and mild forms of preeclampsia. Copyright © 2016 Elsevier Inc. All rights reserved.

Evaluating Iowa Severe Maternal Morbidity Trends and Maternal Risk Factors: 2009-2014.

PubMed

Frederiksen, Brittni N; Lillehoj, Catherine J; Kane, Debra J; Goodman, Dave; Rankin, Kristin

2017-09-01

Objectives To describe statewide SMM trends in Iowa from 2009 to 2014 and identify maternal characteristics associated with SMM, overall and by age group. Methods We used 2009-2014 linked Iowa birth certificate and hospital discharge data to calculate SMM based on a 25-condition definition and 24-condition definition. The 24-condition definition parallels the 25-condition definition, but excludes blood transfusions. We calculated SMM rates for all delivery hospitalizations (N = 196,788) using ICD-9-CM diagnosis and procedure codes. We used log-binomial regression to assess the association of SMM with maternal characteristics, overall and stratified by age groupings. Results In contrast to national rates, Iowa's 25-condition SMM rate decreased from 2009 to 2014. Based on the 25-condition definition, SMM rates were significantly higher among women <20 years and >34 years compared to women 25-34 years. Blood transfusion was the most prevalent indicator, with hysterectomy and disseminated intravascular coagulation (DIC) among the top five conditions. Based on the 24-condition definition, younger women had the lowest SMM rates and older women had the highest SMM rates. SMM rates were also significantly higher among racial/ethnic minorities compared to non-Hispanic white women. Payer was the only risk factor differentially associated with SMM across age groups. First trimester prenatal care initiation was protective for SMM in all models. Conclusions High rates of blood transfusion, hysterectomy, and DIC indicate a need to focus on reducing hemorrhage in Iowa. Both younger and older women and racial/ethnic minorities are identified as high risk groups for SMM that may benefit from special consideration and focus.

Ready or not? School preparedness for California's new personal beliefs exemption law.

PubMed

Wheeler, Marissa; Buttenheim, Alison M

2014-05-07

This paper describes elementary school officials' awareness of and preparedness for the implementation of California's new exemption law that went into effect on January 1, 2014. The new law prescribes stricter requirements for claiming a personal beliefs exemption from mandated school-entry immunizations. We used cross-sectional data collected from a stratified random sample of 315 schools with low, middle, and high rates of personal beliefs exemptions. We described schools' awareness and specific knowledge of the new legislation and tested for differences across school types. We additionally tested for associations between outcome variables and school and respondent characteristics using ordered logit and negative binomial regression. Finally, we described schools' plans and needs for implementing the new legislation. Elementary school staff reported an overall low level of awareness and knowledge about the new legislation and could identify few of its features. We observed, however, that across the exemption-level strata, respondents from high-PBE schools reported significantly higher awareness, knowledge and feature identification compared to respondents from low-PBE schools. Multivariate analyses revealed only one significant association with awareness, knowledge and identification: respondent role. Support staff roles were associated with lower odds of having high self-rated awareness or knowledge compared to health workers, as well as with a reduced log count of features identified. Though most school officials were able to identify a communication plan, schools were still in need of resources and support for successful implementation, in particular, the need for information on the new law. Schools need additional information and support from state and local agencies in order to successfully implement and enforce California's new school immunization law. In particular, our results suggest the need to ensure information on the new law reaches all levels of school staff. Copyright © 2014 Elsevier Ltd. All rights reserved.

Associations between racial discrimination, smoking during pregnancy and low birthweight among Roma.

PubMed

Janevic, Teresa; Osypuk, Theresa; Stojanovski, Kristefer; Jankovic, Janko; Gundersen, Daniel; Rogers, Maggie

2017-06-01

Racial discrimination may increase the risk of low birthweight (LBW), but has not been studied among Roma, the largest minority population in Europe. Moreover, few studies test both institutional and interpersonal forms of racial discrimination on health. Our objective was to examine associations between institutional and interpersonal racial discrimination with LBW, and to test potential mediation by smoking during pregnancy. In 2012-2013, Romani women interviewers surveyed 410 Romani women in Serbia and Macedonia. We measured institutional discrimination (neighborhood segregation, legal status of housing and neighborhood socioeconomic status), interpersonal discrimination [Everyday Discrimination Scale (EDS)], birthweight and smoking by self-report or interviewer report. We estimated relative risks for discrimination on LBW and separately on smoking during pregnancy using log-binomial regression, adjusting for age, parity, years at residence and wealth. The indirect effect of high EDS via smoking on LBW was estimated using inverse odds weighting mediation. Living in a low SES neighborhood showed a 2-fold risk of LBW [adjusted risk ratio (aRR) = 2.4, 95% CI = 1.2, 5.0]; aRRs for segregation and illegal housing were weaker (aRR = 1.8, 95% CI = 0.7, 4.3; aRR = 1.3, 95% CI = 0.6, 2.6, respectively). Institutional measures were not associated with smoking. High EDS was associated with LBW (aRR = 2.4, 95% CI = 1.1, 5.2) and smoking during pregnancy (aRR = 1.4, 95% CI = 1.1, 1.8); the indirect effect of EDS on LBW via smoking was not significant. Interpersonal discrimination and living in a low SES neighborhood were associated with LBW among Roma. Interventions to improve Romani health may benefit from a human rights approach. © The Author 2017. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

Sexual violence, condom negotiation, and condom use in the context of sex work: results from two West African countries.

PubMed

Wirtz, Andrea L; Schwartz, Sheree; Ketende, Sosthenes; Anato, Simplice; Nadedjo, Felicity D; Ouedraogo, Henri G; Ky-Zerbo, Odette; Pitche, Vincent; Grosso, Ashley; Papworth, Erin; Baral, Stefan

2015-03-01

Female sex workers (FSWs) are vulnerable to violence within and beyond the workplace. Violence is associated with increased burden of HIV, possibly explained through physiologic or behavioral causal pathways. These analyses sought to determine the relationship between lifetime sexual violence with unprotected, condomless vaginal intercourse (UVI) among FSWs in West Africa. FSWs (aged ≥18 years) were recruited into a cross-sectional study through respondent-driven sampling in two West African countries, Togo and Burkina Faso. A total of 1380 participants were enrolled from January to July 2013, and completed a sociobehavioral questionnaire and HIV testing. Measures included sex work history, lifetime experiences of violence victimization, sexual practices, and UVI (past month). Crude and adjusted robust log binomial regression was conducted to estimate prevalence ratios (PrR) as a measure of association between UVI with clients and the primary exposure, forced sex. Self-reported lifetime physical abuse (47.3%), forced sex (33.0%), and any violence (57.9%) were common. Almost one-quarter (23.9%) reported recent UVI with clients. History of forced sex was independently associated with recent UVI with clients [vs. none, adjusted PrR: 1.49; 95% confidence interval (CI): 1.18 to 1.88], with evidence of partial mediation by difficult condom negotiation with regular (aPrR: 1.83; 95% CI: 1.43 to 2.34) and new clients (aPrR: 1.60; 95% CI: 1.13 to 2.29). These data demonstrate the significant relationship between sexual violence experienced by FSWs and unprotected sex with clients. Comprehensive interventions reducing vulnerabilities to violence combined with improved condom negotiation are needed to address the complex influences of condom use during sex work as a means of ultimately lowering HIV acquisition and transmission.

Outcomes after intrauterine insemination are independent of provider type

PubMed Central

Goldman, Randi H.; Batsis, Maria; Hacker, Michele R.; Souter, Irene; Petrozza, John C.

2015-01-01

OBJECTIVE We sought to determine whether the success of intrauterine insemination (IUI) varies based on the type of health care provider performing the procedure. STUDY DESIGN This was a retrospective cohort study set at an infertility clinic at an academic institution. The patients who comprised this study were 1575 women who underwent 3475 IUI cycles from late 2003 through early 2012. Cycles were stratified into 3 groups according to the type of provider who performed the procedure: attending physician, fellow physician, or registered nurse (RN). The primary outcome was live birth. Additional outcomes of interest included positive pregnancy test and clinical pregnancy. Repeated measures log binomial regression was used to estimate the risk ratios (RR) and 95% confidence intervals (CI) for the outcomes and to evaluate the effect of potential confounders. All tests were 2-sided, and P values < .05 were considered statistically significant. RESULTS Of the 3475 IUI cycles, 2030 (58.4%) were gonadotropin stimulated, 929 (26.7%) were clomiphene citrate stimulated, and 516 (14.9%) were natural. The incidences of clinical pregnancy and live birth among all cycles were 11.8% and 8.8%, respectively. After adjusting for female age, male partner age, and cycle type, the incidence of live birth was similar for RNs compared with attending physicians (RR, 0.80; 95% CI, 0.58–1.1) and fellow physicians compared with attending physicians (RR, 0.84; 95% CI, 0.58–1.2). Similar results were seen for positive pregnancy test and clinical pregnancy. CONCLUSION There was no significant difference in live birth following IUI cycles in which the procedure was performed by a fellow physician or RN compared with an attending physician. PMID:24881820

Musculoskeletal injuries in professional modern dancers: a prospective cohort study of 15 years.

PubMed

Bronner, Shaw; McBride, Caroline; Gill, Allison

2018-08-01

We analysed work-related musculoskeletal injuries (WMSI) in two modern dance companies to determine whether injury rates decreased and patterns altered compared to previous 3-yr and 6-yr audits (0.48 and 0.25/1000-hrs exposure respectively). In this prospectively designed 15-yr cohort study, data were collected in 30-dancer Company-1 and 12-dancer Company-2. In-house physical therapists tracked WMSI and time-loss-injuries for 159 dancers (42 dancers/yr). 15-yrs were grouped into five 3-yr blocks for comparison with prior audits. Negative binomial logistic regression analyses were conducted with exposure-hrs converted to the natural log and used as the offset variable. Block and company were categorical predictors for dependent variables: WMSI, time-loss-injuries, trauma-injuries and overuse-injuries (p < 0.05). 69% of dancers reported WMSI; 45% sustained at least one time-loss-injury. Company-1, with greater annual exposure, was 1.6-times more likely to sustain time-loss-injuries (p = 0.016, CI = 1.095-2.422) and 5.6-times more likely to sustain time-loss overuse-injuries (p = 0.003, CI = 1.812-17.327). Compared to Block-1, WMSI and time-loss-injuries decreased in Blocks-2, 3, and 5 (p ≤ 0.027). The ratio of time-loss overuse to trauma-injuries was reversed, with trauma-injuries accounting for over 80% of injuries by Block 5. Time-loss-injuries averaged 0.16 injuries/1000-hrs, lower than rates in ballet and sports. Decreased injury rates and changed injury patterns demonstrate efficacious injury management and prevention programming.

Prediction of Compressional Wave Velocity Using Regression and Neural Network Modeling and Estimation of Stress Orientation in Bokaro Coalfield, India

NASA Astrophysics Data System (ADS)

Paul, Suman; Ali, Muhammad; Chatterjee, Rima

2018-01-01

Velocity of compressional wave ( V P) of coal and non-coal lithology is predicted from five wells from the Bokaro coalfield (CF), India. Shear sonic travel time logs are not recorded for all wells under the study area. Shear wave velocity ( Vs) is available only for two wells: one from east and other from west Bokaro CF. The major lithologies of this CF are dominated by coal, shaly coal of Barakar formation. This paper focuses on the (a) relationship between Vp and Vs, (b) prediction of Vp using regression and neural network modeling and (c) estimation of maximum horizontal stress from image log. Coal characterizes with low acoustic impedance (AI) as compared to the overlying and underlying strata. The cross-plot between AI and Vp/ Vs is able to identify coal, shaly coal, shale and sandstone from wells in Bokaro CF. The relationship between Vp and Vs is obtained with excellent goodness of fit ( R 2) ranging from 0.90 to 0.93. Linear multiple regression and multi-layered feed-forward neural network (MLFN) models are developed for prediction Vp from two wells using four input log parameters: gamma ray, resistivity, bulk density and neutron porosity. Regression model predicted Vp shows poor fit (from R 2 = 0.28) to good fit ( R 2 = 0.79) with the observed velocity. MLFN model predicted Vp indicates satisfactory to good R2 values varying from 0.62 to 0.92 with the observed velocity. Maximum horizontal stress orientation from a well at west Bokaro CF is studied from Formation Micro-Imager (FMI) log. Breakouts and drilling-induced fractures (DIFs) are identified from the FMI log. Breakout length of 4.5 m is oriented towards N60°W whereas the orientation of DIFs for a cumulative length of 26.5 m is varying from N15°E to N35°E. The mean maximum horizontal stress in this CF is towards N28°E.

Changes in public attitudes towards confidential adolescent sexual and reproductive health services in Lithuania after the introduction of new legislation: findings from the cross-sectional surveys conducted in 2005 and 2012.

PubMed

Jaruseviciene, Lina; Zaborskis, Apolinaras; Sauliune, Skirmante; Jarusevicius, Gediminas; Lazarus, Jeffrey V

2015-09-04

In Lithuania, the right to confidentiality in healthcare for adolescents over the age of 16 was guaranteed in 2010 through the adoption of new legislation. This study sets out to explore changes in Lithuanian residents' attitudes towards confidentiality protection in adolescent sexual and reproductive healthcare (SRH) by comparing data from surveys administered in 2005 and 2012. For both surveys, the participants were random samples of the Lithuanian residents aged 16 to 74. A 23-item questionnaire was used in 2005 and complemented with 2 items in 2012. Linear regression analysis was employed to estimate absolute differences in prevalence of belief in whether or not adolescents would find confidentiality important when consulting a physician on SRH issues. A log-binomial regression model was fitted to estimate the relative changes (prevalence ratio) of the independent variables. The total number of respondents was 1054 (response rate 83%) in 2005 and 1002 (response rate 80%) in 2012. The proportion of respondents who reported a belief that adolescents would find confidentiality important when seeing a physician for SRH issues increased significantly from 62% in 2005 to 73% in 2012. Regardless of their belief in the importance of confidentiality, in 2012 respondents more often indicated positive outcomes on the relations between the physician and the minor patient, such as increased trust of the adolescent in the physician and more frequent visits to physicians. However, study participants who believed that adolescents would find confidentiality important in 2012 were less optimistic about potential positive outcomes of further legal consolidation of adolescents' right to confidentiality than in 2005. Younger respondents were the most optimistic about potential outcomes if laws were enacted to further protect adolescent confidentiality. This study uncovers the dynamics of public attitudes towards the socially and ethically sensitive issue of adolescent SRH. Our study suggests that legislation could be a factor prompting changes in public opinion, but not sufficient in and of itself for its social acceptance.

Increasing the value of health research in the WHO African Region beyond 2015--reflecting on the past, celebrating the present and building the future: a bibliometric analysis.

PubMed

Uthman, Olalekan A; Wiysonge, Charles Shey; Ota, Martin O; Nicol, Mark; Hussey, Gregory D; Ndumbe, Peter M; Mayosi, Bongani M

2015-03-13

To assess the profile and determinants of health research productivity in Africa since the onset of the new millennium. Bibliometric analysis. In November 2014, we searched PubMed for articles published between 2000 and 2014 from the WHO African Region, and obtained country-level indicators from World Bank data. We used Poisson regression to examine time trends in research publications and negative binomial regression to explore determinants of research publications. We identified 107,662 publications, with a median of 727 per country (range 25-31,757). Three countries (South Africa, Nigeria and Kenya) contributed 52% of the publications. The number of publications increased from 3623 in 2000 to 12,709 in 2014 (relative growth 251%). Similarly, the per cent share of worldwide research publications per year increased from 0.7% in 2000 to 1.3% in 2014. The trend analysis was also significant to confirm a continuous increase in health research publications from Africa, with productivity increasing by 10.3% per year (95% CIs +10.1% to +10.5%). The only independent predictor of publication outputs was national gross domestic product. For every one log US$ billion increase in gross domestic product, research publications rose by 105%: incidence rate ratio (IRR=2.05, 95% CI 1.39 to 3.04). The association of private health expenditure with publications was only marginally significant (IRR=1.86, 95% CI 1.00 to 3.47). There has been a significant improvement in health research in the WHO African Region since 2000, with some individual countries already having strong research profiles. Countries of the region should implement the WHO Strategy on Research for Health: reinforcing the research culture (organisation); focusing research on key health challenges (priorities); strengthening national health research systems (capacity); encouraging good research practice (standards); and consolidating linkages between health research and action (translation). 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.

Soy-Based Infant Formula Feeding and Ultrasound-Detected Uterine Fibroids among Young African-American Women with No Prior Clinical Diagnosis of Fibroids

PubMed Central

Upson, Kristen; Harmon, Quaker E.; Baird, Donna D.

2015-01-01

Background: Early-life soy phytoestrogen exposure has been shown in Eker rats to increase uterine fibroid incidence in adulthood. Two large epidemiologic cohorts have provided some support for increased fibroid risk with infant soy formula feeding in women, but both cohorts relied on self-report of clinically diagnosed fibroids. Objective: We evaluated the relationship between infant soy formula feeding and ultrasound-detected fibroids. Methods: The Study of Environment, Lifestyle & Fibroids (SELF) is an ongoing cohort study of 1,696 African-American women ages 23–34 years with baseline ultrasound screening to detect and measure fibroids ≥ 0.5 cm in diameter. Questionnaire data on soy formula feeding during infancy was ascertained for 1,553 participants (89% based on mother’s report), of whom 345 were found to have fibroids. We estimated the association between soy formula feeding and fibroid prevalence and tumor number using log-binomial regression. Among those with fibroids, we compared fibroid size between soy formula-exposed and unexposed women using multivariable linear regression. Results: We did not observe an association between soy formula feeding and fibroid prevalence [adjusted prevalence ratio (aPR) 0.9, 95% CI: 0.7, 1.3]. Nor were exposed women with fibroids more likely to have ≥ 2 tumors than unexposed women with fibroids (aPR 1.0, 95% CI: 0.7, 1.6). However, exposed women with fibroids had significantly larger fibroids than unexposed women with fibroids. On average, soy formula feeding was associated with a 32% increase in the diameter of the largest fibroid (95% CI: 6%, 65%) and a 127% increase in total tumor volume (95% CI: 12%, 358%). Conclusions: Our observation that women fed soy formula as infants have larger fibroids than unexposed women provides further support for persistent effects of early life phytoestrogen exposure on the uterus. Citation: Upson K, Harmon QE, Baird DD. 2016. Soy-based infant formula feeding and ultrasound-detected uterine fibroids among young African-American women with no prior clinical diagnosis of fibroids. Environ Health Perspect 124:769–775; http://dx.doi.org/10.1289/ehp.1510082 PMID:26565393

Increasing the value of health research in the WHO African Region beyond 2015—reflecting on the past, celebrating the present and building the future: a bibliometric analysis

PubMed Central

Uthman, Olalekan A; Wiysonge, Charles Shey; Ota, Martin O; Nicol, Mark; Hussey, Gregory D; Ndumbe, Peter M; Mayosi, Bongani M

2015-01-01

Objective To assess the profile and determinants of health research productivity in Africa since the onset of the new millennium. Design Bibliometric analysis. Data collection and synthesis In November 2014, we searched PubMed for articles published between 2000 and 2014 from the WHO African Region, and obtained country-level indicators from World Bank data. We used Poisson regression to examine time trends in research publications and negative binomial regression to explore determinants of research publications. Results We identified 107 662 publications, with a median of 727 per country (range 25–31 757). Three countries (South Africa, Nigeria and Kenya) contributed 52% of the publications. The number of publications increased from 3623 in 2000 to 12 709 in 2014 (relative growth 251%). Similarly, the per cent share of worldwide research publications per year increased from 0.7% in 2000 to 1.3% in 2014. The trend analysis was also significant to confirm a continuous increase in health research publications from Africa, with productivity increasing by 10.3% per year (95% CIs +10.1% to +10.5%). The only independent predictor of publication outputs was national gross domestic product. For every one log US$ billion increase in gross domestic product, research publications rose by 105%: incidence rate ratio (IRR=2.05, 95% CI 1.39 to 3.04). The association of private health expenditure with publications was only marginally significant (IRR=1.86, 95% CI 1.00 to 3.47). Conclusions There has been a significant improvement in health research in the WHO African Region since 2000, with some individual countries already having strong research profiles. Countries of the region should implement the WHO Strategy on Research for Health: reinforcing the research culture (organisation); focusing research on key health challenges (priorities); strengthening national health research systems (capacity); encouraging good research practice (standards); and consolidating linkages between health research and action (translation). PMID:25770227

Coffee consumption is not associated with prevalent subclinical cardiovascular disease (CVD) or the risk of CVD events, in nonalcoholic fatty liver disease: results from the multi-ethnic study of atherosclerosis.

PubMed

Simon, Tracey G; Trejo, Maria Esther Perez; Zeb, Irfan; Frazier-Wood, Alexis C; McClelland, Robyn L; Chung, Raymond T; Budoff, Matthew J

2017-10-01

Atherosclerosis and its clinical sequelae represent the leading cause of mortality among patients with nonalcoholic fatty liver disease (NAFLD). While epidemiologic data support the hepatoprotective benefits of coffee in NAFLD, whether coffee improves NAFLD-associated CVD risk is unknown. We examined 3710 ethnically-diverse participants from the Multi-Ethnic Study of Atherosclerosis (MESA) cohort, without history of known liver disease, and with available coffee data from a validated 120-item food frequency questionnaire. All participants underwent baseline non-contrast cardiac CT from which NAFLD was defined by liver:spleen ratio (L:S<1.0), and subclinical CVD was defined by coronary artery calcium (CAC)>0. Major CVD events were defined by the first occurrence of myocardial infarction, cardiac arrest, angina, stroke, or CVD death. We used log-binomial regression to calculate the adjusted prevalence ratio (PR) for CAC>0 by coffee intake and NAFLD status, and events were compared between groups using frequency of events within adjusted Cox proportional hazard regression models. Seventeen percent (N=637) of participants met criteria for NAFLD. NAFLD participants were more likely to have elevated BMI (mean 31.1±5.5kg/m 2 vs. 28.0±5.2kg/m 2 , p<0.0001), and diabetes (22% vs. 11%, p<0.0001), but did not differ in daily coffee consumption (p=0.97). Among NAFLD participants, coffee consumption was not associated with prevalent, baseline CAC>0 (PR=1.02 [0.98-1.07]). Over 12.8years of follow-up, 93 NAFLD and 415 non-NAFLD participants experienced a CV event. However, coffee intake was not associated with incident CVD events, in either NAFLD (HR=1.05 [0.91-1.21]) or non-NAFLD participants (HR=1.03 [0.97-1.11]). In a large, population-based cohort, coffee consumption was not associated with the prevalence of subclinical CVD, nor did coffee impact the future risk of major CVD events, regardless of underlying NAFLD status. Copyright © 2017 Elsevier Inc. All rights reserved.

Large –scale wheat flour folic acid fortification program increases plasma folate levels among women of reproductive age in urban Tanzania

PubMed Central

Abioye, Ajibola I.; Ulenga, Nzovu; Msham, Salum; Kaishozi, George; Gunaratna, Nilupa S; Mwiru, Ramadhani; Smith, Erin; Dhillon, Christina Nyhus; Spiegelman, Donna; Fawzi, Wafaie

2017-01-01

There is widespread vitamin and mineral deficiency problem in Tanzania with known deficiencies of at least vitamin A, iron, folate and zinc, resulting in lasting negative consequences especially on maternal health, cognitive development and thus the nation’s economic potential. Folate deficiency is associated with significant adverse health effects among women of reproductive age, including a higher risk of neural tube defects. Several countries, including Tanzania, have implemented mandatory fortification of wheat and maize flour but evidence on the effectiveness of these programs in developing countries remains limited. We evaluated the effectiveness of Tanzania’s food fortification program by examining folate levels for women of reproductive age, 18–49 years. A prospective cohort study with 600 non-pregnant women enrolled concurrent with the initiation of food fortification and followed up for 1 year thereafter. Blood samples, dietary intake and fortified foods consumption data were collected at baseline, and at 6 and 12 months. Plasma folate levels were determined using a competitive assay with folate binding protein. Using univariate and multivariate linear regression, we compared the change in plasma folate levels at six and twelve months of the program from baseline. We also assessed the relative risk of folate deficiency during follow-up using log-binomial regression. The mean (±SE) pre–fortification plasma folate level for the women was 5.44-ng/ml (±2.30) at baseline. These levels improved significantly at six months [difference: 4.57ng/ml (±2.89)] and 12 months [difference: 4.27ng/ml (±4.18)]. Based on plasma folate cut-off level of 4 ng/ml, the prevalence of folate deficiency was 26.9% at baseline, and 5% at twelve months. One ng/ml increase in plasma folate from baseline was associated with a 25% decreased risk of folate deficiency at 12 months [(RR = 0.75; 95% CI = 0.67–0.85, P<0.001]. In a setting where folate deficiency is high, food fortification program with folic acid resulted in significant improvements in folate status among women of reproductive age. PMID:28797054

Revealing Word Order: Using Serial Position in Binomials to Predict Properties of the Speaker

ERIC Educational Resources Information Center

Iliev, Rumen; Smirnova, Anastasia

2016-01-01

Three studies test the link between word order in binomials and psychological and demographic characteristics of a speaker. While linguists have already suggested that psychological, cultural and societal factors are important in choosing word order in binomials, the vast majority of relevant research was focused on general factors and on broadly…

A watershed's response to logging and roads: South Fork of Caspar Creek, California, 1967-1976

Treesearch

Raymond M. Rice; Forest B. Tilley; Patricia A. Datzman

1979-01-01

The effect of logging and roadbuilding on erosion and sedimentation are analyzed by comparing the North Fork and South Fork of Caspar Creek, in northern California. Increased sediment production during the 4 years after road construction, was 326 cu yd/sq mi/yr—80 percent greater than that predicted by the predisturbance regression analysis. The average...

On comparison of net survival curves.

PubMed

Pavlič, Klemen; Perme, Maja Pohar

2017-05-02

Relative survival analysis is a subfield of survival analysis where competing risks data are observed, but the causes of death are unknown. A first step in the analysis of such data is usually the estimation of a net survival curve, possibly followed by regression modelling. Recently, a log-rank type test for comparison of net survival curves has been introduced and the goal of this paper is to explore its properties and put this methodological advance into the context of the field. We build on the association between the log-rank test and the univariate or stratified Cox model and show the analogy in the relative survival setting. We study the properties of the methods using both the theoretical arguments as well as simulations. We provide an R function to enable practical usage of the log-rank type test. Both the log-rank type test and its model alternatives perform satisfactory under the null, even if the correlation between their p-values is rather low, implying that both approaches cannot be used simultaneously. The stratified version has a higher power in case of non-homogeneous hazards, but also carries a different interpretation. The log-rank type test and its stratified version can be interpreted in the same way as the results of an analogous semi-parametric additive regression model despite the fact that no direct theoretical link can be established between the test statistics.

Jump-and-return sandwiches: A new family of binomial-like selective inversion sequences with improved performance.

PubMed

Brenner, Tom; Chen, Johnny; Stait-Gardner, Tim; Zheng, Gang; Matsukawa, Shingo; Price, William S

2018-03-01

A new family of binomial-like inversion sequences, named jump-and-return sandwiches (JRS), has been developed by inserting a binomial-like sequence into a standard jump-and-return sequence, discovered through use of a stochastic Genetic Algorithm optimisation. Compared to currently used binomial-like inversion sequences (e.g., 3-9-19 and W5), the new sequences afford wider inversion bands and narrower non-inversion bands with an equal number of pulses. As an example, two jump-and-return sandwich 10-pulse sequences achieved 95% inversion at offsets corresponding to 9.4% and 10.3% of the non-inversion band spacing, compared to 14.7% for the binomial-like W5 inversion sequence, i.e., they afforded non-inversion bands about two thirds the width of the W5 non-inversion band. Copyright © 2018 Elsevier Inc. All rights reserved.

Risk Factors for Proximal Junctional Kyphosis Associated With Dual-rod Growing-rod Surgery for Early-onset Scoliosis.

PubMed

Watanabe, Kota; Uno, Koki; Suzuki, Teppei; Kawakami, Noriaki; Tsuji, Taichi; Yanagida, Haruhisa; Ito, Manabu; Hirano, Toru; Yamazaki, Ken; Minami, Shohei; Taneichi, Hiroshi; Imagama, Shiro; Takeshita, Katsushi; Yamamoto, Takuya; Matsumoto, Morio

2016-10-01

A retrospective, multicenter study. To identify risk factors for proximal junctional kyphosis (PJK) when treating early-onset scoliosis (EOS) with dual-rod growing-rod (GR) procedure. The risk factors for PJK associated with GR treatment for EOS have not been adequately studied. We evaluated clinical and radiographic results from 88 patients with EOS who underwent dual-rod GR surgery in 12 spine centers in Japan. The mean age at the time of the initial surgery was 6.5±2.2 years (range, 1.5-9.8 y), and the mean follow-up period was 3.9±2.6 years (range, 2.0-12.0 y). Risk factors for PJK were analyzed by binomial multiple logistic regression analysis. The potential factors analyzed were sex, etiology, age, the number of rod-lengthening procedures, coronal and sagittal parameters on radiographs, the type of foundation (pedicle screws or hooks), the uppermost level of the proximal foundation, and the lowermost level of the distal foundation. PJK developed in 23 patients (26%); in 19 of these, the proximal foundation became dislodged following PJK. Binomial multiple logistic regression analysis identified the following significant independent risk factors for PJK: a lower instrumented vertebra at or cranial to L3 [odds ratio (OR), 3.32], a proximal thoracic scoliosis of ≥40 degrees (OR, 2.95), and a main thoracic kyphosis of ≥60 degrees (OR, 5.08). The significant independent risk factors for PJK during dual-rod GR treatment for EOS were a lower instrumented vertebra at or cranial to L3, a proximal thoracic scoliosis of ≥40 degrees, and a main thoracic kyphosis of ≥60 degrees.

Making sense of the noise: The effect of hydrology on silver carp eDNA detection in the Chicago area waterway system.

PubMed

Song, Jeffery W; Small, Mitchell J; Casman, Elizabeth A

2017-12-15

Environmental DNA (eDNA) sampling is an emerging tool for monitoring the spread of aquatic invasive species. One confounding factor when interpreting eDNA sampling evidence is that eDNA can be present in the water in the absence of living target organisms, originating from excreta, dead tissue, boats, or sewage effluent, etc. In the Chicago Area Waterway System (CAWS), electric fish dispersal barriers were built to prevent non-native Asian carp species from invading Lake Michigan, and yet Asian carp eDNA has been detected above the barriers sporadically since 2009. In this paper the influence of stream flow characteristics in the CAWS on the probability of invasive Asian carp eDNA detection in the CAWS from 2009 to 2012 was examined. In the CAWS, the direction of stream flow is mostly away from Lake Michigan, though there are infrequent reversals in flow direction towards Lake Michigan during dry spells. We find that the flow reversal volume into the Lake has a statistically significant positive relationship with eDNA detection probability, while other covariates, like gage height, precipitation, season, water temperature, dissolved oxygen concentration, pH and chlorophyll concentration do not. This suggests that stream flow direction is highly influential on eDNA detection in the CAWS and should be considered when interpreting eDNA evidence. We also find that the beta-binomial regression model provides a stronger fit for eDNA detection probability compared to a binomial regression model. This paper provides a statistical modeling framework for interpreting eDNA sampling evidence and for evaluating covariates influencing eDNA detection. Copyright © 2017 Elsevier B.V. All rights reserved.

Dental plaque, preventive care, and tooth brushing associated with dental caries in primary teeth in schoolchildren ages 6–9 years of Leon, Nicaragua

PubMed Central

del Socorro Herrera, Miriam; Medina-Solis, Carlo Eduardo; Minaya-Sánchez, Mirna; Pontigo-Loyola, América Patricia; Villalobos-Rodelo, Juan José; Islas-Granillo, Horacio; de la Rosa-Santillana, Rubén; Maupomé, Gerardo

2013-01-01

Background Our study aimed to evaluate the effect of various risk indicators for dental caries on primary teeth of Nicaraguan children (from Leon, Nicaragua) ages 6 to 9, using the negative binomial regression model. Material/Methods A cross-sectional study was carried out to collect clinical, demographic, socioeconomic, and behavioral data from 794 schoolchildren ages 6 to 9 years, randomly selected from 25 schools in the city of León, Nicaragua. Clinical examinations for dental caries (dmft index) were performed by 2 trained and standardized examiners. Socio-demographic, socioeconomic, and behavioral data were self-reported using questionnaires. Multivariate negative binomial regression (NBR) analysis was used. Results Mean age was 7.49±1.12 years. Boys accounted for 50.1% of the sample. Mean dmft was 3.54±3.13 and caries prevalence (dmft >0) was 77.6%. In the NBR multivariate model (p<0.05), for each year of age, the expected mean dmft decreased by 7.5%. Brushing teeth at least once a day and having received preventive dental care in the last year before data collection were associated with declines in the expected mean dmft by 19.5% and 69.6%, respectively. Presence of dental plaque increased the expected mean dmft by 395.5%. Conclusions The proportion of students with caries in this sample was high. We found associations between dental caries in the primary dentition and dental plaque, brushing teeth at least once a day, and having received preventive dental care. To improve oral health, school programs and/or age-appropriate interventions need to be developed based on the specific profile of caries experience and the associated risk indicators. PMID:24247119

Gingival recession and associated factors in a homogeneous Mexican adult male population: A cross-sectional study

PubMed Central

Minaya-Sánchez, Mirna; Medina-Solís, Carlo E.; Vallejos-Sánchez, Ana A.; Marquez-Corona, Maria L.; Pontigo-Loyola, América P.; Islas-Granillo, Horacio; Maupomé, Gerardo

2012-01-01

Background: Diverse variables are implicated in the pathogenesis of gingival recession; more detailed knowledge about the relationship between the clinical presentation of gingival recession and assorted risk indicators may lead to improved patient monitoring, early intervention, and subsequent prevention. The objective was to evaluate clinically gingival recession in a homogeneous Mexican adult male population and to determine the strength of association with related factors. Method: A cross-sectional study was carried out in a largely homogeneous group in terms of ethnic background, socioeconomic status, gender, occupation, and medical/dental insurance, in Campeche, Mexico. Periodontal examinations were undertaken to determine diverse clinical dental variables. All periodontal clinical examinations were assessed using the Florida Probe System, a dental chair and one examiner. Questionnaires were used to collect diverse risk indicators. Statistical analyses were undertaken with negative binomial regression models. Results: The mean number of sites with gingival recession per subject was 6.73±5.81; the prevalence was 87.6%. In the negative binomial regression model we observed that for (i) each year of age, and (ii) each percentage unit of increase in sites with plaque, and (iii) with suppuration, mean sites with gingival recession increased 2.9%, 1.0% and 13.0%, respectively. Having a spouse was associated with gingival recession. Conclusions: We observed association between gingival recession, and sociodemographic and clinical parameters. Patients need to be educated about risk indicators for gingival recession as well as the preventive maneuvers that may be implemented to minimize its occurrence. The potential of improved oral self-care to prevent a largely benign condition such as gingival recession is important, given the associated disorders that may ensue root exposure, such as root caries and root hypersensitivity. Key words:Oral health, periodontal health, gingival recession, adults, Mexico. PMID:22549678

Influence of prehospital airway management on neurological outcome in patients transferred to a heart attack centre following out-of-hospital cardiac arrest.

PubMed

Edwards, Timothy; Williams, Julia; Cottee, Michaela

2018-05-11

To describe the association between prehospital airway management and neurological outcomes in patients transferred by the ambulance service directly to a heart attack centre (HAC) post-return of spontaneous circulation (ROSC). A retrospective observational cohort study in which ambulance records were reviewed to determine prehospital airway management strategy and collect physiological and demographic data. HAC notes were obtained to determine in-hospital management and quantify neurological outcome via the cerebral performance category (CPC) scale. Statistical analyses were performed via χ 2 -test, Mann-Whitney U-test, odds ratios and binomial logistic regression. Two hundred and twenty patients were included between August 2013 and August 2014, with complete outcome data obtained for 209. Median age of patients with complete outcome data was 67 years and 71.3% were male (n = 149). Airway management was provided using a supraglottic airway (SGA) in 72.7% of cases (n = 152) with the remainder undergoing endotracheal intubation (ETI). There was no significant difference in the proportion of patients who had a good neurological outcome (CPC 1 and 2) at discharge between the SGA and ETI groups (P = 0.29). Binomial logistic regression incorporating factors known to influence outcome demonstrated no significant difference in neurological outcomes between the SGA and ETI groups (adjusted OR 0.73, 95% CI 0.34-1.56). In this observational study, there was no significant difference in the proportion of good neurological outcomes in patients managed with SGA versus ETI during cardiac arrest and in the post-ROSC transfer phase. Further research is required to provide more definitive evidence in relation to the optimal airway management strategy in out-of-hospital cardiac arrest. © 2018 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

Recurrent suicide attempts in patients with depressive and anxiety disorders: the role of borderline personality traits.

PubMed

Stringer, Barbara; van Meijel, Berno; Eikelenboom, Merijn; Koekkoek, Bauke; Licht, Carmilla M M; Kerkhof, Ad J F M; Penninx, Brenda W J H; Beekman, Aartjan T F

2013-10-01

The presence of a comorbid borderline personality disorder (BPD) may be associated with an increase of suicidal behaviors in patients with depressive and anxiety disorders. The aim of this study is to examine the role of borderline personality traits on recurrent suicide attempts. The Netherlands Study on Depression and Anxiety included 1838 respondents with lifetime depressive and/or anxiety disorders, of whom 309 reported at least one previous suicide attempt. A univariable negative binomial regression analysis was performed to examine the association between comorbid borderline personality traits and suicide attempts. Univariable and multivariable negative binomial regression analyses were performed to identify risk factors for the number of recurrent suicide attempts in four clusters (type and severity of axis-I disorders, BPD traits, determinants of suicide attempts and socio-demographics). In the total sample the suicide attempt rate ratio increased with 33% for every unit increase in BPD traits. A lifetime diagnosis of dysthymia and comorbid BPD traits, especially the symptoms anger and fights, were independently and significantly associated with recurrent suicide attempts in the final model (n=309). The screening of personality disorders was added to the NESDA assessments at the 4-year follow-up for the first time. Therefore we were not able to examine the influence of comorbid BPD traits on suicide attempts over time. Persons with a lifetime diagnosis of dysthymia combined with borderline personality traits especially difficulties in coping with anger seemed to be at high risk for recurrent suicide attempts. For clinical practice, it is recommended to screen for comorbid borderline personality traits and to strengthen the patient's coping skills with regard to anger. © 2013 Elsevier B.V. All rights reserved.

Quality of maternity care and its determinants along the continuum in Kenya: A structural equation modeling analysis

PubMed Central

Mendez, Bomar Rojas

2017-01-01

Background Improving access to delivery services does not guarantee access to quality obstetric care and better survival, and therefore, concerns for quality of maternal and newborn care in low- and middle-income countries have been raised. Our study explored characteristics associated with the quality of initial assessment, intrapartum, and immediate postpartum and newborn care, and further assessed the relationships along the continuum of care. Methods The 2010 Service Provision Assessment data of Kenya for 627 routine deliveries of women aged 15–49 were used. Quality of care measures were assessed using recently validated quality of care measures during initial assessment, intrapartum, and postpartum periods. Data were analyzed with negative binomial regression and structural equation modeling technique. Results The negative binomial regression results identified a number of determinants of quality, such as the level of health facilities, managing authority, presence of delivery fee, central electricity supply and clinical guideline for maternal and neonatal care. Our structural equation modeling (SEM) further demonstrated that facility characteristics were important determinants of quality for initial assessment and postpartum care, while characteristics at the provider level became more important in shaping the quality of intrapartum care. Furthermore we also noted that quality of initial assessment had a positive association with quality of intrapartum care (β = 0.71, p < 0.001), which in turn was positively associated with the quality of newborn and immediate postpartum care (β = 1.29, p = 0.004). Conclusions A continued focus on quality of care along the continuum of maternity care is important not only to mothers but also their newborns. Policymakers should therefore ensure that required resources, as well as adequate supervision and emphasis on the quality of obstetric care, are available. PMID:28520771

Homicide mortality rates in Canada, 2000-2009: Youth at increased risk.

PubMed

Basham, C Andrew; Snider, Carolyn

2016-10-20

To estimate and compare Canadian homicide mortality rates (HMRs) and trends in HMRs across age groups, with a focus on trends for youth. Data for the period of 2000 to 2009 were collected from Statistics Canada's CANSIM (Canadian Statistical Information Management) Table 102-0540 with the following ICD-10-CA coded external causes of death: X85 to Y09 (assault) and Y87.1 (sequelae of assault). Annual population counts from 2000 to 2009 were obtained from Statistics Canada's CANSIM Table 051-0001. Both death and population counts were organized into five-year age groups. A random effects negative binomial regression analysis was conducted to estimate age group-specific rates, rate ratios, and trends in homicide mortality. There were 9,878 homicide deaths in Canada during the study period. The increase in the overall homicide mortality rate (HMR) of 0.3% per year was not statistically significant (95% CI: -1.1% to +1.8%). Canadians aged 15-19 years and 20-24 years had the highest HMRs during the study period, and experienced statistically significant annual increases in their HMRs of 3% and 4% respectively (p < 0.05). A general, though not statistically significant, decrease in the HMR was observed for all age groups 50+ years. A fixed effects negative binomial regression model showed that the HMR for males was higher than for females over the study period [RRfemale/male = 0.473 (95% CI: 0.361, 0.621)], but no significant difference in sex-specific trends in the HMR was found. An increasing risk of homicide mortality was identified among Canadian youth, ages 15-24, over the 10-year study period. Research that seeks to understand the reasons for the increased homicide risk facing Canada's youth, and public policy responses to reduce this risk, are warranted.

Dental plaque, preventive care, and tooth brushing associated with dental caries in primary teeth in schoolchildren ages 6-9 years of Leon, Nicaragua.

PubMed

Herrera, Miriam del Socorro; Medina-Solís, Carlo Eduardo; Minaya-Sánchez, Mirna; Pontigo-Loyola, América Patricia; Villalobos-Rodelo, Juan José; Islas-Granillo, Horacio; de la Rosa-Santillana, Rubén; Maupomé, Gerardo

2013-11-19

Our study aimed to evaluate the effect of various risk indicators for dental caries on primary teeth of Nicaraguan children (from Leon, Nicaragua) ages 6 to 9, using the negative binomial regression model. A cross-sectional study was carried out to collect clinical, demographic, socioeconomic, and behavioral data from 794 schoolchildren ages 6 to 9 years, randomly selected from 25 schools in the city of León, Nicaragua. Clinical examinations for dental caries (dmft index) were performed by 2 trained and standardized examiners. Socio-demographic, socioeconomic, and behavioral data were self-reported using questionnaires. Multivariate negative binomial regression (NBR) analysis was used. Mean age was 7.49 ± 1.12 years. Boys accounted for 50.1% of the sample. Mean dmft was 3.54 ± 3.13 and caries prevalence (dmft >0) was 77.6%. In the NBR multivariate model (p<0.05), for each year of age, the expected mean dmft decreased by 7.5%. Brushing teeth at least once a day and having received preventive dental care in the last year before data collection were associated with declines in the expected mean dmft by 19.5% and 69.6%, respectively. Presence of dental plaque increased the expected mean dmft by 395.5%. The proportion of students with caries in this sample was high. We found associations between dental caries in the primary dentition and dental plaque, brushing teeth at least once a day, and having received preventive dental care. To improve oral health, school programs and/or age-appropriate interventions need to be developed based on the specific profile of caries experience and the associated risk indicators.

Use of Proteomic and Hematology Biomarkers for Prediction of Hematopoietic Acute Radiation Syndrome Severity in Baboon Radiation Models.

PubMed

Blakely, William F; Bolduc, David L; Debad, Jeff; Sigal, George; Port, Matthias; Abend, Michael; Valente, Marco; Drouet, Michel; Hérodin, Francis

2018-07-01

Use of plasma proteomic and hematological biomarkers represents a promising approach to provide useful diagnostic information for assessment of the severity of hematopoietic acute radiation syndrome. Eighteen baboons were evaluated in a radiation model that underwent total-body and partial-body irradiations at doses of Co gamma rays from 2.5 to 15 Gy at dose rates of 6.25 cGy min and 32 cGy min. Hematopoietic acute radiation syndrome severity levels determined by an analysis of blood count changes measured up to 60 d after irradiation were used to gauge overall hematopoietic acute radiation syndrome severity classifications. A panel of protein biomarkers was measured on plasma samples collected at 0 to 28 d after exposure using electrochemiluminescence-detection technology. The database was split into two distinct groups (i.e., "calibration," n = 11; "validation," n = 7). The calibration database was used in an initial stepwise regression multivariate model-fitting approach followed by down selection of biomarkers for identification of subpanels of hematopoietic acute radiation syndrome-responsive biomarkers for three time windows (i.e., 0-2 d, 2-7 d, 7-28 d). Model 1 (0-2 d) includes log C-reactive protein (p < 0.0001), log interleukin-13 (p < 0.0054), and procalcitonin (p < 0.0316) biomarkers; model 2 (2-7 d) includes log CD27 (p < 0.0001), log FMS-related tyrosine kinase 3 ligand (p < 0.0001), log serum amyloid A (p < 0.0007), and log interleukin-6 (p < 0.0002); and model 3 (7-28 d) includes log CD27 (p < 0.0012), log serum amyloid A (p < 0.0002), log erythropoietin (p < 0.0001), and log CD177 (p < 0.0001). The predicted risk of radiation injury categorization values, representing the hematopoietic acute radiation syndrome severity outcome for the three models, produced least squares multiple regression fit confidences of R = 0.73, 0.82, and 0.75, respectively. The resultant algorithms support the proof of concept that plasma proteomic biomarkers can supplement clinical signs and symptoms to assess hematopoietic acute radiation syndrome risk severity.

Usage and users of online self-management programs for adult patients with atopic dermatitis and food allergy: an explorative study.

PubMed

van Os-Medendorp, Harmieke; van Leent-de Wit, Ilse; de Bruin-Weller, Marjolein; Knulst, André

2015-05-23

Two online self-management programs for patients with atopic dermatitis (AD) or food allergy (FA) were developed with the aim of helping patients cope with their condition, follow the prescribed treatment regimen, and deal with the consequences of their illness in daily life. Both programs consist of several modules containing information, personal stories by fellow patients, videos, and exercises with feedback. Health care professionals can refer their patients to the programs. However, the use of the program in daily practice is unknown. The aim of this study was to explore the use and characteristics of users of the online self-management programs "Living with eczema," and "Living with food allergy," and to investigate factors related to the use of the trainings. A cross-sectional design was carried out in which the outcome parameters were the number of log-ins by patients, the number of hits on the system's core features, disease severity, quality of life, and domains of self-management. Descriptive statistics were used to summarize sample characteristics and to describe number of log-ins and hits per module and per functionality. Correlation and regression analyses were used to explore the relation between the number of log-ins and patient characteristics. Since the start, 299 adult patients have been referred to the online AD program; 173 logged in for at least one occasion. Data from 75 AD patients were available for analyses. Mean number of log-ins was 3.1 (range 1-11). Linear regression with the number of log-ins as dependent variable showed that age and quality of life contributed most to the model, with betas of .35 ( P=.002) and .26 (P=.05), respectively, and an R(2) of .23. Two hundred fourteen adult FA patients were referred to the online FA training, 124 logged in for at least one occasion and data from 45 patients were available for analysis. Mean number of log-ins was 3.0 (range 1-11). Linear regression with the number of log-ins as dependent variable revealed that adding the self-management domain "social integration and support" to the model led to an R(2) of .13. The modules with information about the disease, diagnosis, and treatment were most visited. Most hits were on the information parts of the modules (55-58%), followed by exercises (30-32%). The online self-management programs "Living with eczema" and "Living with food allergy" were used by patients in addition to the usual face-to-face care. Almost 60% of all referred patients logged in, with an average of three log-ins. All modules seemed to be relevant, but there is room for improvement in the use of the training. Age, quality of life, and lower social integration and support were related to the use of the training, but only part of the variance in use could be explained by these variables.

Modeling the frequency of opposing left-turn conflicts at signalized intersections using generalized linear regression models.

PubMed

Zhang, Xin; Liu, Pan; Chen, Yuguang; Bai, Lu; Wang, Wei

2014-01-01

The primary objective of this study was to identify whether the frequency of traffic conflicts at signalized intersections can be modeled. The opposing left-turn conflicts were selected for the development of conflict predictive models. Using data collected at 30 approaches at 20 signalized intersections, the underlying distributions of the conflicts under different traffic conditions were examined. Different conflict-predictive models were developed to relate the frequency of opposing left-turn conflicts to various explanatory variables. The models considered include a linear regression model, a negative binomial model, and separate models developed for four traffic scenarios. The prediction performance of different models was compared. The frequency of traffic conflicts follows a negative binominal distribution. The linear regression model is not appropriate for the conflict frequency data. In addition, drivers behaved differently under different traffic conditions. Accordingly, the effects of conflicting traffic volumes on conflict frequency vary across different traffic conditions. The occurrences of traffic conflicts at signalized intersections can be modeled using generalized linear regression models. The use of conflict predictive models has potential to expand the uses of surrogate safety measures in safety estimation and evaluation.

Work-related injuries involving a hand or fingers among union carpenters in Washington State, 1989 to 2008.

PubMed

Lipscomb, Hester J; Schoenfisch, Ashley; Cameron, Wilfrid

2013-07-01

We evaluated work-related injuries involving a hand or fingers and associated costs among a cohort of 24,830 carpenters between 1989 and 2008. Injury rates and rate ratios were calculated by using Poisson regression to explore higher risk on the basis of age, sex, time in the union, predominant work, and calendar time. Negative binomial regression was used to model dollars paid per claim after adjustment for inflation and discounting. Hand injuries accounted for 21.1% of reported injuries and 9.5% of paid lost time injuries. Older carpenters had proportionately more amputations, fractures, and multiple injuries, but their rates of these more severe injuries were not higher. Costs exceeded $21 million, a cost burden of $0.11 per hour worked. Older carpenters' higher proportion of serious injuries in the absence of higher rates likely reflects age-related reporting differences.

Mental Health Symptoms Among Student Service Members/Veterans and Civilian College Students.

PubMed

Cleveland, Sandi D; Branscum, Adam J; Bovbjerg, Viktor E; Thorburn, Sheryl

2015-01-01

The aim of this study was to investigate if and to what extent student service members/veterans differ from civilian college students in the prevalence of self-reported symptoms of poor mental health. The Fall 2011 implementation of the American College Health Association-National College Health Assessment included 27,774 respondents from 44 colleges and universities. Participants were matched using propensity scores, and the prevalence of symptoms was compared using logistic regression and zero-inflated negative binomial regression models. The odds of feeling overwhelmed in the last 12 months were significantly lower among student service members/veterans with a history of hazardous duty (odd ratio [OR] = 0.46, adjusted p value <.05) compared with civilian students. Military service, with and without hazardous duty deployment, was not a significant predictor of the total number of symptoms of poor mental health. Current student service members/veterans may not be disproportionately affected by poor psychological functioning.

Work performance decrements are associated with Australian working conditions, particularly the demand to work longer hours.

PubMed

Holden, Libby; Scuffham, Paul A; Hilton, Michael F; Vecchio, Nerina N; Whiteford, Harvey A

2010-03-01

To demonstrate the importance of including a range of working conditions in models exploring the association between health- and work-related performance. The Australian Work Outcomes Research Cost-benefit study cross-sectional screening data set was used to explore health-related absenteeism and work performance losses on a sample of approximately 78,000 working Australians, including available demographic and working condition factors. Data collected using the World Health Organization Health and Productivity Questionnaire were analyzed with negative binomial logistic regression and multinomial logistic regressions for absenteeism and work performance, respectively. Hours expected to work, annual wage, and job insecurity play a vital role in the association between health- and work-related performance for both work attendance and self-reported work performance. Australian working conditions are contributing to both absenteeism and low work performance, regardless of health status.

Perceived health status and daily activity participation of older Malaysians.

PubMed

Ng, Sor Tho; Tengku-Aizan, Hamid; Tey, Nai Peng

2011-07-01

This article investigates the influence of perceived health status on the daily activity participation of older Malaysians. Data from the Survey on Perceptions of Needs and Problems of the Elderly, which was conducted in 1999, were used. The negative binomial regression results show that older persons with good perceived health status reported more varieties of daily activity participation, especially among the uneducated and those with below-average self-esteem. The multinomial logistic regression model suggests that older persons with good perceived health status tended to engage daily in paid work only or with leisure activities, whereas those perceived to have poor health were more likely to engage in leisure activities only or leisure and family role activities. Promotion of a healthy lifestyle at a younger age encourages every person to monitor and take responsibility for their own health, which is a necessary strategy to ensure active participation at an older age, and thus improve their well-being.

A general framework for the use of logistic regression models in meta-analysis.

PubMed

Simmonds, Mark C; Higgins, Julian Pt

2016-12-01

Where individual participant data are available for every randomised trial in a meta-analysis of dichotomous event outcomes, "one-stage" random-effects logistic regression models have been proposed as a way to analyse these data. Such models can also be used even when individual participant data are not available and we have only summary contingency table data. One benefit of this one-stage regression model over conventional meta-analysis methods is that it maximises the correct binomial likelihood for the data and so does not require the common assumption that effect estimates are normally distributed. A second benefit of using this model is that it may be applied, with only minor modification, in a range of meta-analytic scenarios, including meta-regression, network meta-analyses and meta-analyses of diagnostic test accuracy. This single model can potentially replace the variety of often complex methods used in these areas. This paper considers, with a range of meta-analysis examples, how random-effects logistic regression models may be used in a number of different types of meta-analyses. This one-stage approach is compared with widely used meta-analysis methods including Bayesian network meta-analysis and the bivariate and hierarchical summary receiver operating characteristic (ROC) models for meta-analyses of diagnostic test accuracy. © The Author(s) 2014.

USING LINEAR AND POLYNOMIAL MODELS TO EXAMINE THE ENVIRONMENTAL STABILITY OF VIRUSES

EPA Science Inventory

The article presents the development of model equations for describing the fate of viral infectivity in environmental samples. Most of the models were based upon the use of a two-step linear regression approach. The first step employs regression of log base 10 transformed viral t...

LAS bioconcentration is isomer specific

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tolls, J.; Haller, M.; Graaf, I. de

1995-12-31

The authors measured parent compound specific bioconcentration data for linear alkylbenzene sulfonates in Pimephales promelas. They did so by using cold, custom synthesized sulfophenyl alkanes. They observed that, within homologous series of isomers, the uptake rate constants (k{sub 1}) and the bioconcentration factor (BCF) increase with increasing number of carbon atoms in the alkyl chain (n{sub C-atoms}). In contrast, the elimination rate constant k{sub 2} appears to be independent of the alkyl chain length. Regressions of log BCF vs n{sub C-atoms} yielded different slopes for the homologous groups of the 5- and the 2-sulfophenyl alkane isomers. Regression of all logmore » BCF-data vs log 1/CMC yielded a good description of the data. However, when regressing the data for both homologous series separately again very different slopes are obtained. The results therefore indicate that hydrophobicity-bioconcentration relationships may be different for different homologous groups of sulfophenyl alkanes.« less

Choosing a Transformation in Analyses of Insect Counts from Contagious Distributions with Low Means

Treesearch

W.D. Pepper; S.J. Zarnoch; G.L. DeBarr; P. de Groot; C.D. Tangren

1997-01-01

Guidelines based on computer simulation are suggested for choosing a transformation of insect counts from negative binomial distributions with low mean counts and high levels of contagion. Typical values and ranges of negative binomial model parameters were determined by fitting the model to data from 19 entomological field studies. Random sampling of negative binomial...

Adjusted Wald Confidence Interval for a Difference of Binomial Proportions Based on Paired Data

ERIC Educational Resources Information Center

Bonett, Douglas G.; Price, Robert M.

2012-01-01

Adjusted Wald intervals for binomial proportions in one-sample and two-sample designs have been shown to perform about as well as the best available methods. The adjusted Wald intervals are easy to compute and have been incorporated into introductory statistics courses. An adjusted Wald interval for paired binomial proportions is proposed here and…

Comparison of multiplicity distributions to the negative binomial distribution in muon-proton scattering

NASA Astrophysics Data System (ADS)

Arneodo, M.; Arvidson, A.; Aubert, J. J.; Badełek, B.; Beaufays, J.; Bee, C. P.; Benchouk, C.; Berghoff, G.; Bird, I.; Blum, D.; Böhm, E.; de Bouard, X.; Brasse, F. W.; Braun, H.; Broll, C.; Brown, S.; Brück, H.; Calen, H.; Chima, J. S.; Ciborowski, J.; Clifft, R.; Coignet, G.; Combley, F.; Coughlan, J.; D'Agostini, G.; Dahlgren, S.; Dengler, F.; Derado, I.; Dreyer, T.; Drees, J.; Düren, M.; Eckardt, V.; Edwards, A.; Edwards, M.; Ernst, T.; Eszes, G.; Favier, J.; Ferrero, M. I.; Figiel, J.; Flauger, W.; Foster, J.; Ftáčnik, J.; Gabathuler, E.; Gajewski, J.; Gamet, R.; Gayler, J.; Geddes, N.; Grafström, P.; Grard, F.; Haas, J.; Hagberg, E.; Hasert, F. J.; Hayman, P.; Heusse, P.; Jaffré, M.; Jachołkowska, A.; Janata, F.; Jancsó, G.; Johnson, A. S.; Kabuss, E. M.; Kellner, G.; Korbel, V.; Krüger, J.; Kullander, S.; Landgraf, U.; Lanske, D.; Loken, J.; Long, K.; Maire, M.; Malecki, P.; Manz, A.; Maselli, S.; Mohr, W.; Montanet, F.; Montgomery, H. E.; Nagy, E.; Nassalski, J.; Norton, P. R.; Oakham, F. G.; Osborne, A. M.; Pascaud, C.; Pawlik, B.; Payre, P.; Peroni, C.; Peschel, H.; Pessard, H.; Pettinghale, J.; Pietrzyk, B.; Pietrzyk, U.; Pönsgen, B.; Pötsch, M.; Renton, P.; Ribarics, P.; Rith, K.; Rondio, E.; Sandacz, A.; Scheer, M.; Schlagböhmer, A.; Schiemann, H.; Schmitz, N.; Schneegans, M.; Schneider, A.; Scholz, M.; Schröder, T.; Schultze, K.; Sloan, T.; Stier, H. E.; Studt, M.; Taylor, G. N.; Thénard, J. M.; Thompson, J. C.; de La Torre, A.; Toth, J.; Urban, L.; Urban, L.; Wallucks, W.; Whalley, M.; Wheeler, S.; Williams, W. S. C.; Wimpenny, S. J.; Windmolders, R.; Wolf, G.

1987-09-01

The multiplicity distributions of charged hadrons produced in the deep inelastic muon-proton scattering at 280 GeV are analysed in various rapidity intervals, as a function of the total hadronic centre of mass energy W ranging from 4 20 GeV. Multiplicity distributions for the backward and forward hemispheres are also analysed separately. The data can be well parameterized by binomial distributions, extending their range of applicability to the case of lepton-proton scattering. The energy and the rapidity dependence of the parameters is presented and a smooth transition from the negative binomial distribution via Poissonian to the ordinary binomial is observed.

Chromatographic behaviour predicts the ability of potential nootropics to permeate the blood-brain barrier.

PubMed

Farsa, Oldřich

2013-01-01

The log BB parameter is the logarithm of the ratio of a compound's equilibrium concentrations in the brain tissue versus the blood plasma. This parameter is a useful descriptor in assessing the ability of a compound to permeate the blood-brain barrier. The aim of this study was to develop a Hansch-type linear regression QSAR model that correlates the parameter log BB and the retention time of drugs and other organic compounds on a reversed-phase HPLC containing an embedded amide moiety. The retention time was expressed by the capacity factor log k'. The second aim was to estimate the brain's absorption of 2-(azacycloalkyl)acetamidophenoxyacetic acids, which are analogues of piracetam, nefiracetam, and meclofenoxate. Notably, these acids may be novel nootropics. Two simple regression models that relate log BB and log k' were developed from an assay performed using a reversed-phase HPLC that contained an embedded amide moiety. Both the quadratic and linear models yielded statistical parameters comparable to previously published models of log BB dependence on various structural characteristics. The models predict that four members of the substituted phenoxyacetic acid series have a strong chance of permeating the barrier and being absorbed in the brain. The results of this study show that a reversed-phase HPLC system containing an embedded amide moiety is a functional in vitro surrogate of the blood-brain barrier. These results suggest that racetam-type nootropic drugs containing a carboxylic moiety could be more poorly absorbed than analogues devoid of the carboxyl group, especially if the compounds penetrate the barrier by a simple diffusion mechanism.

Analytical performance of the Hologic Aptima HBV Quant Assay and the COBAS Ampliprep/COBAS TaqMan HBV test v2.0 for the quantification of HBV DNA in plasma samples.

PubMed

Schønning, Kristian; Johansen, Kim; Nielsen, Lone Gilmor; Weis, Nina; Westh, Henrik

2018-07-01

Quantification of HBV DNA is used for initiating and monitoring antiviral treatment. Analytical test performance consequently impacts treatment decisions. To compare the analytical performance of the Aptima HBV Quant Assay (Aptima) and the COBAS Ampliprep/COBAS TaqMan HBV Test v2.0 (CAPCTMv2) for the quantification of HBV DNA in plasma samples. The performance of the two tests was compared on 129 prospective plasma samples, and on 63 archived plasma samples of which 53 were genotyped. Linearity of the two assays was assessed on dilutions series of three clinical samples (Genotype B, C, and D). Bland-Altman analysis of 120 clinical samples, which quantified in both tests, showed an average quantification bias (Aptima - CAPCTMv2) of -0.19 Log IU/mL (SD: 0.33 Log IU/mL). A single sample quantified more than three standard deviations higher in Aptima than in CAPCTMv2. Only minor differences were observed between genotype A (N = 4; average difference -0.01 Log IU/mL), B (N = 8; -0.13 Log IU/mL), C (N = 8; -0.31 Log IU/mL), D (N = 25; -0.22 Log IU/mL), and E (N = 7; -0.03 Log IU/mL). Deming regression showed that the two tests were excellently correlated (slope of the regression line 1.03; 95% CI: 0.998-1.068). Linearity of the tests was evaluated on dilution series and showed an excellent correlation of the two tests. Both tests were precise with %CV less than 3% for HBV DNA ≥3 Log IU/mL. The Aptima and CAPCTMv2 tests are highly correlated, and both tests are useful for monitoring patients chronically infected with HBV. Copyright © 2018 Elsevier B.V. All rights reserved.

[Association of mineral and bone disorder with increasing PWV in CKD 1-5 patients].

PubMed

Shiota, Jun; Watanabe, Mitsuhiro

2007-01-01

The association between pulse wave velocity(PWV) and chronic kidney disease mineral and bone disorder(CKD-MBD) was investigated in CKD 1-5 patients without dialysis. Pulse pressure(PP), PWV, serum Cr, non-HDL-cholesterol, Alb, Ca, Pi, calcitriol, intact-PTH and BAP were measured in sixty patients not receiving a phosphate binder or vitamin D. Using the relationship between age and baPWV in healthy subjects, we determined delta baPWV(measured baPWV-calculated baPWV) as an index for the effect of CKD-related factors. delta baPWV was significantly higher in diabetic patients (p < 0.00001). Simple regression analysis revealed that delta baPWV was positively correlated with PP (p < 0.05) and Log(intact-PTH) (p < 0.01), but negatively correlated with Log(estimated GFR) and Log(calcitriol) (p < 0.01). Multiple regression analysis revealed that delta baPWV was significantly associated with PP and calcitriol, or PP and intact-PTH. These results suggest a relationship between PWV and CKD-MBD.

On the p, q-binomial distribution and the Ising model

NASA Astrophysics Data System (ADS)

Lundow, P. H.; Rosengren, A.

2010-08-01

We employ p, q-binomial coefficients, a generalisation of the binomial coefficients, to describe the magnetisation distributions of the Ising model. For the complete graph this distribution corresponds exactly to the limit case p = q. We apply our investigation to the simple d-dimensional lattices for d = 1, 2, 3, 4, 5 and fit p, q-binomial distributions to our data, some of which are exact but most are sampled. For d = 1 and d = 5, the magnetisation distributions are remarkably well-fitted by p,q-binomial distributions. For d = 4 we are only slightly less successful, while for d = 2, 3 we see some deviations (with exceptions!) between the p, q-binomial and the Ising distribution. However, at certain temperatures near T c the statistical moments of the fitted distribution agree with the moments of the sampled data within the precision of sampling. We begin the paper by giving results of the behaviour of the p, q-distribution and its moment growth exponents given a certain parameterisation of p, q. Since the moment exponents are known for the Ising model (or at least approximately for d = 3) we can predict how p, q should behave and compare this to our measured p, q. The results speak in favour of the p, q-binomial distribution's correctness regarding its general behaviour in comparison to the Ising model. The full extent to which they correctly model the Ising distribution, however, is not settled.

Prevalence, Severity, and Prognostic Value of Sleep Apnea Syndromes in Cardiac Amyloidosis

PubMed Central

Bodez, Diane; Guellich, Aziz; Kharoubi, Mounira; Covali-Noroc, Ala; Tissot, Claire-Marie; Guendouz, Soulef; Hittinger, Luc; Dubois-Randé, Jean-Luc; Lefaucheur, Jean-Pascal; Planté-Bordeneuve, Violaine; Adnot, Serge; Boyer, Laurent; Damy, Thibaud

2016-01-01

Study Objectives: To assess prevalence, severity, and prognostic value of sleep-disordered breathing (SDB), in the three main cardiac amyloidosis (CA) types, i.e., light-chain (AL), transthyretin-related familial (m-TTR), or senile (WT-TTR). Methods: Patients consecutively referred for CA diagnosis work-up underwent cardiac assessment and nocturnal polygraphy. SDB was defined as apnea-hypopnea index (AHI) ≥ 5/h. Multivariate analysis was used to identify predictors of a major adverse cardiac event (MACE) defined as death, heart transplantation and acute heart failure. Results: Seventy CA patients were included (31 AL, 22 m-TTR, 17 WT-TTR). The mean ± standard deviation age and left ventricular ejection fraction were 71 ± 12 years and 49% ± 13% and median (interquartile range) N terminal pro brain natriuretic peptide (NT-proBNP) was 3,932 (1,607; 7,028) pg/mL. The prevalence of SDB was 90% without difference between amyloidosis types. SDB was central in 27% and obstructive in 73%. AL had less frequent severe SDB compared to m-TTR and WT-TTR (P = 0.015) but longer time with peripheral capillary oxygen saturation (SpO2) < 90% (P = 0.037). After a median follow-up of 7.5 (2.8; 14.9) months, 49% patients experienced MACE. Time with nocturnal SpO2 < 90% was the only independent predictor of MACE. The best-identified threshold was 30 min. Values > 30 min were associated with bad prognosis (Log-rank χ2: 8.01, P value = 0.005). Using binomial logistic regression, determinants of time with nocturnal SpO2 < 90% were New York Heart Association class (P = 0.011), and log-NT-proBNP (P = 0.04) but not AHI. Conclusions: In CA population, prevalence of SDB is high (90%) and dominated by the obstructive pattern. Bad prognosis in this population was driven by nocturnal desaturation, reflecting heart failure severity and respiratory involvement. Citation: Bodez D, Guellich A, Kharoubi M, Covali-Noroc A, Tissot CM, Guendouz S, Hittinger L, Dubois-Randé JL, Lefaucheur JP, Planté-Bordeneuve V, Adnot S, Boyer L, Damy T. Prevalence, severity, and prognostic value of sleep apnea syndromes in cardiac amyloidosis. SLEEP 2016;39(7):1333–1341. PMID:27091529

On the equivalence of case-crossover and time series methods in environmental epidemiology.

PubMed

Lu, Yun; Zeger, Scott L

2007-04-01

The case-crossover design was introduced in epidemiology 15 years ago as a method for studying the effects of a risk factor on a health event using only cases. The idea is to compare a case's exposure immediately prior to or during the case-defining event with that same person's exposure at otherwise similar "reference" times. An alternative approach to the analysis of daily exposure and case-only data is time series analysis. Here, log-linear regression models express the expected total number of events on each day as a function of the exposure level and potential confounding variables. In time series analyses of air pollution, smooth functions of time and weather are the main confounders. Time series and case-crossover methods are often viewed as competing methods. In this paper, we show that case-crossover using conditional logistic regression is a special case of time series analysis when there is a common exposure such as in air pollution studies. This equivalence provides computational convenience for case-crossover analyses and a better understanding of time series models. Time series log-linear regression accounts for overdispersion of the Poisson variance, while case-crossover analyses typically do not. This equivalence also permits model checking for case-crossover data using standard log-linear model diagnostics.

Using mixed treatment comparisons and meta-regression to perform indirect comparisons to estimate the efficacy of biologic treatments in rheumatoid arthritis.

PubMed

Nixon, R M; Bansback, N; Brennan, A

2007-03-15

Mixed treatment comparison (MTC) is a generalization of meta-analysis. Instead of the same treatment for a disease being tested in a number of studies, a number of different interventions are considered. Meta-regression is also a generalization of meta-analysis where an attempt is made to explain the heterogeneity between the treatment effects in the studies by regressing on study-level covariables. Our focus is where there are several different treatments considered in a number of randomized controlled trials in a specific disease, the same treatment can be applied in several arms within a study, and where differences in efficacy can be explained by differences in the study settings. We develop methods for simultaneously comparing several treatments and adjusting for study-level covariables by combining ideas from MTC and meta-regression. We use a case study from rheumatoid arthritis. We identified relevant trials of biologic verses standard therapy or placebo and extracted the doses, comparators and patient baseline characteristics. Efficacy is measured using the log odds ratio of achieving six-month ACR50 responder status. A random-effects meta-regression model is fitted which adjusts the log odds ratio for study-level prognostic factors. A different random-effect distribution on the log odds ratios is allowed for each different treatment. The odds ratio is found as a function of the prognostic factors for each treatment. The apparent differences in the randomized trials between tumour necrosis factor alpha (TNF- alpha) antagonists are explained by differences in prognostic factors and the analysis suggests that these drugs as a class are not different from each other. Copyright (c) 2006 John Wiley & Sons, Ltd.

Environmental, Spatial, and Sociodemographic Factors Associated with Nonfatal Injuries in Indonesia.

PubMed

Irianti, Sri; Prasetyoputra, Puguh

2017-01-01

Background . The determinants of injuries and their reoccurrence in Indonesia are not well understood, despite their importance in the prevention of injuries. Therefore, this study seeks to investigate the environmental, spatial, and sociodemographic factors associated with the reoccurrence of injuries among Indonesian people. Methods . Data from the 2013 round of the Indonesia Baseline Health Research (IBHR 2013) were analysed using a two-part hurdle regression model. A logit regression model was chosen for the zero-hurdle part , while a zero-truncated negative binomial regression model was selected for the counts part . Odds ratio (OR) and incidence rate ratio (IRR) were the measures of association, respectively. Results . The results suggest that living in a household with distant drinking water source, residing in slum areas, residing in Eastern Indonesia, having low educational attainment, being men, and being poorer are positively related to the likelihood of experiencing injury. Moreover, being a farmer or fishermen, having low educational attainment, and being men are positively associated with the frequency of injuries. Conclusion . This study would be useful to prioritise injury prevention programs in Indonesia based on the environmental, spatial, and sociodemographic characteristics.