Prediction of liver disease in patients whose liver function tests have been checked in primary care: model development and validation using population-based observational cohorts.

PubMed

McLernon, David J; Donnan, Peter T; Sullivan, Frank M; Roderick, Paul; Rosenberg, William M; Ryder, Steve D; Dillon, John F

2014-06-02

To derive and validate a clinical prediction model to estimate the risk of liver disease diagnosis following liver function tests (LFTs) and to convert the model to a simplified scoring tool for use in primary care. Population-based observational cohort study of patients in Tayside Scotland identified as having their LFTs performed in primary care and followed for 2 years. Biochemistry data were linked to secondary care, prescriptions and mortality data to ascertain baseline characteristics of the derivation cohort. A separate validation cohort was obtained from 19 general practices across the rest of Scotland to externally validate the final model. Primary care, Tayside, Scotland. Derivation cohort: LFT results from 310 511 patients. After exclusions (including: patients under 16 years, patients having initial LFTs measured in secondary care, bilirubin >35 μmol/L, liver complications within 6 weeks and history of a liver condition), the derivation cohort contained 95 977 patients with no clinically apparent liver condition. Validation cohort: after exclusions, this cohort contained 11 653 patients. Diagnosis of a liver condition within 2 years. From the derivation cohort (n=95 977), 481 (0.5%) were diagnosed with a liver disease. The model showed good discrimination (C-statistic=0.78). Given the low prevalence of liver disease, the negative predictive values were high. Positive predictive values were low but rose to 20-30% for high-risk patients. This study successfully developed and validated a clinical prediction model and subsequent scoring tool, the Algorithm for Liver Function Investigations (ALFI), which can predict liver disease risk in patients with no clinically obvious liver disease who had their initial LFTs taken in primary care. ALFI can help general practitioners focus referral on a small subset of patients with higher predicted risk while continuing to address modifiable liver disease risk factors in those at lower risk. Published

Development and validation of a brief screening instrument for psychosocial risk associated with genetic testing: a pan-Canadian cohort study

PubMed Central

Esplen, Mary Jane; Cappelli, Mario; Wong, Jiahui; Bottorff, Joan L; Hunter, Jon; Carroll, June; Dorval, Michel; Wilson, Brenda; Allanson, Judith; Semotiuk, Kara; Aronson, Melyssa; Bordeleau, Louise; Charlemagne, Nicole; Meschino, Wendy

2013-01-01

Objectives To develop a brief, reliable and valid instrument to screen psychosocial risk among those who are undergoing genetic testing for Adult-Onset Hereditary Disease (AOHD). Design A prospective two-phase cohort study. Setting 5 genetic testing centres for AOHD, such as cancer, Huntington's disease or haemochromatosis, in ambulatory clinics of tertiary hospitals across Canada. Participants 141 individuals undergoing genetic testing were approached and consented to the instrument development phase of the study (Phase I). The Genetic Psychosocial Risk Instrument (GPRI) developed in Phase I was tested in Phase II for item refinement and validation. A separate cohort of 722 individuals consented to the study, 712 completed the baseline package and 463 completed all follow-up assessments. Most participants were female, at the mid-life stage. Individuals in advanced stages of the illness or with cognitive impairment or a language barrier were excluded. Interventions Phase I: GPRI items were generated from (1) a review of the literature, (2) input from genetic counsellors and (3) phase I participants. Phase II: further item refinement and validation were conducted with a second cohort of participants who completed the GPRI at baseline and were followed for psychological distress 1-month postgenetic testing results. Primary and secondary outcome measures GPRI, Hamilton Depression Rating Scale (HAM-D), Hamilton Anxiety Rating Scale (HAM-A), Brief Symptom Inventory (BSI) and Impact of Event Scale (IES). Results The final 20-item GPRI had a high reliability—Cronbach's α at 0.81. The construct validity was supported by high correlations between GPRI and BSI and IES. The predictive value was demonstrated by a receiver operating characteristic curve of 0.78 plotting GPRI against follow-up assessments using HAM-D and HAM-A. Conclusions With a cut-off score of 50, GPRI identified 84% of participants who displayed distress postgenetic testing results, supporting its

Development and validation of risk prediction algorithms to estimate future risk of common cancers in men and women: prospective cohort study

PubMed Central

Hippisley-Cox, Julia; Coupland, Carol

2015-01-01

Objective To derive and validate a set of clinical risk prediction algorithm to estimate the 10-year risk of 11 common cancers. Design Prospective open cohort study using routinely collected data from 753 QResearch general practices in England. We used 565 practices to develop the scores and 188 for validation. Subjects 4.96 million patients aged 25–84 years in the derivation cohort; 1.64 million in the validation cohort. Patients were free of the relevant cancer at baseline. Methods Cox proportional hazards models in the derivation cohort to derive 10-year risk algorithms. Risk factors considered included age, ethnicity, deprivation, body mass index, smoking, alcohol, previous cancer diagnoses, family history of cancer, relevant comorbidities and medication. Measures of calibration and discrimination in the validation cohort. Outcomes Incident cases of blood, breast, bowel, gastro-oesophageal, lung, oral, ovarian, pancreas, prostate, renal tract and uterine cancers. Cancers were recorded on any one of four linked data sources (general practitioner (GP), mortality, hospital or cancer records). Results We identified 228 241 incident cases during follow-up of the 11 types of cancer. Of these 25 444 were blood; 41 315 breast; 32 626 bowel, 12 808 gastro-oesophageal; 32 187 lung; 4811 oral; 6635 ovarian; 7119 pancreatic; 35 256 prostate; 23 091 renal tract; 6949 uterine cancers. The lung cancer algorithm had the best performance with an R2 of 64.2%; D statistic of 2.74; receiver operating characteristic curve statistic of 0.91 in women. The sensitivity for the top 10% of women at highest risk of lung cancer was 67%. Performance of the algorithms in men was very similar to that for women. Conclusions We have developed and validated a prediction models to quantify absolute risk of 11 common cancers. They can be used to identify patients at high risk of cancers for prevention or further assessment. The algorithms could be integrated into clinical

Sex-Specific Associations between Particulate Matter Exposure and Gene Expression in Independent Discovery and Validation Cohorts of Middle-Aged Men and Women.

PubMed

Vrijens, Karen; Winckelmans, Ellen; Tsamou, Maria; Baeyens, Willy; De Boever, Patrick; Jennen, Danyel; de Kok, Theo M; Den Hond, Elly; Lefebvre, Wouter; Plusquin, Michelle; Reynders, Hans; Schoeters, Greet; Van Larebeke, Nicolas; Vanpoucke, Charlotte; Kleinjans, Jos; Nawrot, Tim S

2017-04-01

Particulate matter (PM) exposure leads to premature death, mainly due to respiratory and cardiovascular diseases. Identification of transcriptomic biomarkers of air pollution exposure and effect in a healthy adult population. Microarray analyses were performed in 98 healthy volunteers (48 men, 50 women). The expression of eight sex-specific candidate biomarker genes (significantly associated with PM 10 in the discovery cohort and with a reported link to air pollution-related disease) was measured with qPCR in an independent validation cohort (75 men, 94 women). Pathway analysis was performed using Gene Set Enrichment Analysis. Average daily PM 2.5 and PM 10 exposures over 2-years were estimated for each participant's residential address using spatiotemporal interpolation in combination with a dispersion model. Average long-term PM 10 was 25.9 (± 5.4) and 23.7 (± 2.3) μg/m 3 in the discovery and validation cohorts, respectively. In discovery analysis, associations between PM 10 and the expression of individual genes differed by sex. In the validation cohort, long-term PM 10 was associated with the expression of DNAJB5 and EAPP in men and ARHGAP4 ( p = 0.053) in women. AKAP6 and LIMK1 were significantly associated with PM 10 in women, although associations differed in direction between the discovery and validation cohorts. Expression of the eight candidate genes in the discovery cohort differentiated between validation cohort participants with high versus low PM 10 exposure (area under the receiver operating curve = 0.92; 95% CI: 0.85, 1.00; p = 0.0002 in men, 0.86; 95% CI: 0.76, 0.96; p = 0.004 in women). Expression of the sex-specific candidate genes identified in the discovery population predicted PM 10 exposure in an independent cohort of adults from the same area. Confirmation in other populations may further support this as a new approach for exposure assessment, and may contribute to the discovery of molecular mechanisms for PM-induced health effects.

Development and validation of QMortality risk prediction algorithm to estimate short term risk of death and assess frailty: cohort study.

PubMed

Hippisley-Cox, Julia; Coupland, Carol

2017-09-20

Objectives  To derive and validate a risk prediction equation to estimate the short term risk of death, and to develop a classification method for frailty based on risk of death and risk of unplanned hospital admission. Design  Prospective open cohort study. Participants  Routinely collected data from 1436 general practices contributing data to QResearch in England between 2012 and 2016. 1079 practices were used to develop the scores and a separate set of 357 practices to validate the scores. 1.47 million patients aged 65-100 years were in the derivation cohort and 0.50 million patients in the validation cohort. Methods  Cox proportional hazards models in the derivation cohort were used to derive separate risk equations in men and women for evaluation of the risk of death at one year. Risk factors considered were age, sex, ethnicity, deprivation, smoking status, alcohol intake, body mass index, medical conditions, specific drugs, social factors, and results of recent investigations. Measures of calibration and discrimination were determined in the validation cohort for men and women separately and for each age and ethnic group. The new mortality equation was used in conjunction with the existing QAdmissions equation (which predicts risk of unplanned hospital admission) to classify patients into frailty groups. Main outcome measure  The primary outcome was all cause mortality. Results  During follow-up 180 132 deaths were identified in the derivation cohort arising from 4.39 million person years of observation. The final model included terms for age, body mass index, Townsend score, ethnic group, smoking status, alcohol intake, unplanned hospital admissions in the past 12 months, atrial fibrillation, antipsychotics, cancer, asthma or chronic obstructive pulmonary disease, living in a care home, congestive heart failure, corticosteroids, cardiovascular disease, dementia, epilepsy, learning disability, leg ulcer, chronic liver disease or pancreatitis

New evidence on the validity of the Arnett Caregiver Interaction Scale: Results from the Early Childhood Longitudinal Study-Birth Cohort

PubMed Central

Colwell, Nicole; Gordon, Rachel A.; Fujimoto, Ken; Kaestner, Robert; Korenman, Sanders

2013-01-01

The Arnett Caregiver Interaction Scale (CIS) has been widely used in research studies to measure the quality of caregiver–child interactions. The scale was modeled on a well-established theory of parenting, but there are few psychometric studies of its validity. We applied factor analyses and item response theory methods to assess the psychometric properties of the Arnett CIS in a national sample of toddlers in home-based care and preschoolers in center-based care from the Early Childhood Longitudinal Study-Birth Cohort. We found that a bifactor structure (one common factor and a second set of specific factors) best fits the data. In the Arnett CIS, the bifactor model distinguishes a common substantive dimension from two methodological dimensions (for positively and negatively oriented items). Despite the good fit of this model, the items are skewed (most teachers/caregivers display positive interactions with children) and, as a result, the Arnett CIS is not well suited to distinguish between caregivers who are “highly” versus “moderately” positive in their interactions with children, according to the items on the scale. Regression-adjusted associations between the Arnett CIS and child outcomes are small, especially for preschoolers in centers. We encourage future scale development work on measures of child care quality by early childhood scholars. PMID:24058264

Development and validation of risk prediction equations to estimate future risk of blindness and lower limb amputation in patients with diabetes: cohort study

PubMed Central

Coupland, Carol

2015-01-01

Study question Is it possible to develop and externally validate risk prediction equations to estimate the 10 year risk of blindness and lower limb amputation in patients with diabetes aged 25-84 years? Methods This was a prospective cohort study using routinely collected data from general practices in England contributing to the QResearch and Clinical Practice Research Datalink (CPRD) databases during the study period 1998-2014. The equations were developed using 763 QResearch practices (n=454 575 patients with diabetes) and validated in 254 different QResearch practices (n=142 419) and 357 CPRD practices (n=206 050). Cox proportional hazards models were used to derive separate risk equations for blindness and amputation in men and women that could be evaluated at 10 years. Measures of calibration and discrimination were calculated in the two validation cohorts. Study answer and limitations Risk prediction equations to quantify absolute risk of blindness and amputation in men and women with diabetes have been developed and externally validated. In the QResearch derivation cohort, 4822 new cases of lower limb amputation and 8063 new cases of blindness occurred during follow-up. The risk equations were well calibrated in both validation cohorts. Discrimination was good in men in the external CPRD cohort for amputation (D statistic 1.69, Harrell’s C statistic 0.77) and blindness (D statistic 1.40, Harrell’s C statistic 0.73), with similar results in women and in the QResearch validation cohort. The algorithms are based on variables that patients are likely to know or that are routinely recorded in general practice computer systems. They can be used to identify patients at high risk for prevention or further assessment. Limitations include lack of formally adjudicated outcomes, information bias, and missing data. What this study adds Patients with type 1 or type 2 diabetes are at increased risk of blindness and amputation but generally do not have accurate

Development and validation of risk prediction equations to estimate future risk of blindness and lower limb amputation in patients with diabetes: cohort study.

PubMed

Hippisley-Cox, Julia; Coupland, Carol

2015-11-11

Is it possible to develop and externally validate risk prediction equations to estimate the 10 year risk of blindness and lower limb amputation in patients with diabetes aged 25-84 years? This was a prospective cohort study using routinely collected data from general practices in England contributing to the QResearch and Clinical Practice Research Datalink (CPRD) databases during the study period 1998-2014. The equations were developed using 763 QResearch practices (n=454,575 patients with diabetes) and validated in 254 different QResearch practices (n=142,419) and 357 CPRD practices (n=206,050). Cox proportional hazards models were used to derive separate risk equations for blindness and amputation in men and women that could be evaluated at 10 years. Measures of calibration and discrimination were calculated in the two validation cohorts. Risk prediction equations to quantify absolute risk of blindness and amputation in men and women with diabetes have been developed and externally validated. In the QResearch derivation cohort, 4822 new cases of lower limb amputation and 8063 new cases of blindness occurred during follow-up. The risk equations were well calibrated in both validation cohorts. Discrimination was good in men in the external CPRD cohort for amputation (D statistic 1.69, Harrell's C statistic 0.77) and blindness (D statistic 1.40, Harrell's C statistic 0.73), with similar results in women and in the QResearch validation cohort. The algorithms are based on variables that patients are likely to know or that are routinely recorded in general practice computer systems. They can be used to identify patients at high risk for prevention or further assessment. Limitations include lack of formally adjudicated outcomes, information bias, and missing data. Patients with type 1 or type 2 diabetes are at increased risk of blindness and amputation but generally do not have accurate assessments of the magnitude of their individual risks. The new algorithms calculate

Development and initial cohort validation of the Arthritis Research UK Musculoskeletal Health Questionnaire (MSK-HQ) for use across musculoskeletal care pathways.

PubMed

Hill, Jonathan C; Kang, Sujin; Benedetto, Elena; Myers, Helen; Blackburn, Steven; Smith, Stephanie; Dunn, Kate M; Hay, Elaine; Rees, Jonathan; Beard, David; Glyn-Jones, Sion; Barker, Karen; Ellis, Benjamin; Fitzpatrick, Ray; Price, Andrew

2016-08-05

Current musculoskeletal outcome tools are fragmented across different healthcare settings and conditions. Our objectives were to develop and validate a single musculoskeletal outcome measure for use throughout the pathway and patients with different musculoskeletal conditions: the Arthritis Research UK Musculoskeletal Health Questionnaire (MSK-HQ). A consensus workshop with stakeholders from across the musculoskeletal community, workshops and individual interviews with a broad mix of musculoskeletal patients identified and prioritised outcomes for MSK-HQ inclusion. Initial psychometric validation was conducted in four cohorts from community physiotherapy, and secondary care orthopaedic hip, knee and shoulder clinics. Stakeholders (n=29) included primary care, physiotherapy, orthopaedic and rheumatology patients (n=8); general practitioners, physiotherapists, orthopaedists, rheumatologists and pain specialists (n=7), patient and professional national body representatives (n=10), and researchers (n=4). The four validation cohorts included 570 participants (n=210 physiotherapy, n=150 hip, n=150 knee, n=60 shoulder patients). Outcomes included the MSK-HQ's acceptability, feasibility, comprehension, readability and responder burden. The validation cohort outcomes were the MSK-HQ's completion rate, test-retest reliability and convergent validity with reference standards (EQ-5D-5L, Oxford Hip, Knee, Shoulder Scores, and the Keele MSK-PROM). Musculoskeletal domains prioritised were pain severity, physical function, work interference, social interference, sleep, fatigue, emotional health, physical activity, independence, understanding, confidence to self-manage and overall impact. Patients reported MSK-HQ items to be 'highly relevant' and 'easy to understand'. Completion rates were high (94.2%), with scores normally distributed, and no floor/ceiling effects. Test-retest reliability was excellent, and convergent validity was strong (correlations 0.81-0.88). A new

Palliative care and prognosis in COPD: a systematic review with a validation cohort.

PubMed

Almagro, Pere; Yun, Sergi; Sangil, Ana; Rodríguez-Carballeira, Mónica; Marine, Meritxell; Landete, Pedro; Soler-Cataluña, Juan José; Soriano, Joan B; Miravitlles, Marc

2017-01-01

Current recommendations to consider initiation of palliative care (PC) in COPD patients are often based on an expected poor prognosis. However, this approach is not evidence-based, and which and when COPD patients should start PC is controversial. We aimed to assess whether current suggested recommendations for initiating PC were sufficiently reliable. We identified prognostic variables proposed in the literature for initiating PC; then, we ascertained their relationship with 1-year mortality, and finally, we validated their utility in our cohort of 697 patients hospitalized for COPD exacerbation. From 24 articles of 499 screened, we selected 20 variables and retrieved 48 original articles in which we were able to calculate the relationship between each of them and 1-year mortality. The number of studies where 1-year mortality was detailed for these variables ranged from 9 for previous hospitalizations or FEV 1 ≤30% to none for albumin ≤25 mg/dL. The percentage of 1-year mortality in the literature for these variables ranged from 5% to 60%. In the validation cohort study, the prevalence of these proposed variables ranged from 8% to 64%; only 10 of the 18 variables analyzed in our cohort reached statistical significance with Cox regression analysis, and none overcame an area under the curve ≥0.7. We conclude that none of the suggested criteria for initiating PC based on an expected poor vital prognosis in COPD patients in the short or medium term offers sufficient reliability, and consequently, they should be avoided as exclusive criteria for considering PC or at least critically appraised.

Palliative care and prognosis in COPD: a systematic review with a validation cohort

PubMed Central

Almagro, Pere; Yun, Sergi; Sangil, Ana; Rodríguez-Carballeira, Mónica; Marine, Meritxell; Landete, Pedro; Soler-Cataluña, Juan José; Soriano, Joan B; Miravitlles, Marc

2017-01-01

Current recommendations to consider initiation of palliative care (PC) in COPD patients are often based on an expected poor prognosis. However, this approach is not evidence-based, and which and when COPD patients should start PC is controversial. We aimed to assess whether current suggested recommendations for initiating PC were sufficiently reliable. We identified prognostic variables proposed in the literature for initiating PC; then, we ascertained their relationship with 1-year mortality, and finally, we validated their utility in our cohort of 697 patients hospitalized for COPD exacerbation. From 24 articles of 499 screened, we selected 20 variables and retrieved 48 original articles in which we were able to calculate the relationship between each of them and 1-year mortality. The number of studies where 1-year mortality was detailed for these variables ranged from 9 for previous hospitalizations or FEV1 ≤30% to none for albumin ≤25 mg/dL. The percentage of 1-year mortality in the literature for these variables ranged from 5% to 60%. In the validation cohort study, the prevalence of these proposed variables ranged from 8% to 64%; only 10 of the 18 variables analyzed in our cohort reached statistical significance with Cox regression analysis, and none overcame an area under the curve ≥0.7. We conclude that none of the suggested criteria for initiating PC based on an expected poor vital prognosis in COPD patients in the short or medium term offers sufficient reliability, and consequently, they should be avoided as exclusive criteria for considering PC or at least critically appraised. PMID:28652724

Validation of metabolic syndrome using medical records in the SUN cohort

PubMed Central

2011-01-01

Background The objective of this study was to evaluate the validity of self reported criteria of Metabolic Syndrome (MS) in the SUN (Seguimiento Universidad de Navarra) cohort using their medical records as the gold standard. Methods We selected 336 participants and we obtained MS related data according to Adult Treatment Panel III (ATP III) and International Diabetes Federation (IDF). Then we compared information on the self reported diagnosis of MS and MS diagnosed in their medical records. We calculated the proportion of confirmed MS, the proportion of confirmed non-MS and the intraclass correlation coefficients for each component of the MS. Results From those 336 selected participants, we obtained sufficient data in 172 participants to confirm or reject MS using ATP III criteria. The proportion of confirmed MS was 91.2% (95% CI: 80.7- 97.1) and the proportion of confirmed non-MS was 92.2% (95% CI: 85.7-96.4) using ATP III criteria. The proportion of confirmed MS using IDF criteria was 100% (95% CI: 87.2-100) and the proportion of confirmed non-MS was 97.1% (95% CI: 85.1-99.9). Kappa Index was 0.82 in the group diagnosed by ATP III criteria and 0.97 in the group diagnosed by IDF criteria. Intraclass correlation coefficients for the different component of MS were: 0.93 (IC 95%:0.91- 0.95) for BMI; 0.96 (IC 95%: 0.93-0.98) for waist circumference; 0.75 (IC 95%: 0.66-0.82) for fasting glucose; 0.50 (IC 95%:0.35-0.639) for HDL cholesterol; 0.78 (IC 95%: 0.70-0.84) for triglycerides; 0.49 (IC 95%:0.34-0.61) for systolic blood pressure and 0.55 (IC 95%: 0.41-0.65) for diastolic blood pressure. Conclusions Self-reported MS based on self reported components of the SM in a Spanish cohort of university graduates was sufficiently valid as to be used in epidemiological studies. PMID:22085407

Development and validation of QDiabetes-2018 risk prediction algorithm to estimate future risk of type 2 diabetes: cohort study.

PubMed

Hippisley-Cox, Julia; Coupland, Carol

2017-11-20

Objectives  To derive and validate updated QDiabetes-2018 prediction algorithms to estimate the 10 year risk of type 2 diabetes in men and women, taking account of potential new risk factors, and to compare their performance with current approaches. Design  Prospective open cohort study. Setting  Routinely collected data from 1457 general practices in England contributing to the QResearch database: 1094 were used to develop the scores and a separate set of 363 were used to validate the scores. Participants  11.5 million people aged 25-84 and free of diabetes at baseline: 8.87 million in the derivation cohort and 2.63 million in the validation cohort. Methods  Cox proportional hazards models were used in the derivation cohort to derive separate risk equations in men and women for evaluation at 10 years. Risk factors considered included those already in QDiabetes (age, ethnicity, deprivation, body mass index, smoking, family history of diabetes in a first degree relative, cardiovascular disease, treated hypertension, and regular use of corticosteroids) and new risk factors: atypical antipsychotics, statins, schizophrenia or bipolar affective disorder, learning disability, gestational diabetes, and polycystic ovary syndrome. Additional models included fasting blood glucose and glycated haemoglobin (HBA1c). Measures of calibration and discrimination were determined in the validation cohort for men and women separately and for individual subgroups by age group, ethnicity, and baseline disease status. Main outcome measure  Incident type 2 diabetes recorded on the general practice record. Results  In the derivation cohort, 178 314 incident cases of type 2 diabetes were identified during follow-up arising from 42.72 million person years of observation. In the validation cohort, 62 326 incident cases of type 2 diabetes were identified from 14.32 million person years of observation. All new risk factors considered met our model inclusion criteria. Model A included

A Molecular Host Response Assay to Discriminate Between Sepsis and Infection-Negative Systemic Inflammation in Critically Ill Patients: Discovery and Validation in Independent Cohorts

PubMed Central

McHugh, Leo; Seldon, Therese A.; Brandon, Roslyn A.; Kirk, James T.; Rapisarda, Antony; Sutherland, Allison J.; Presneill, Jeffrey J.; Venter, Deon J.; Lipman, Jeffrey; Thomas, Mervyn R.; Klein Klouwenberg, Peter M. C.; van Vught, Lonneke; Scicluna, Brendon; Bonten, Marc; Cremer, Olaf L.; Schultz, Marcus J.; van der Poll, Tom; Yager, Thomas D.; Brandon, Richard B.

2015-01-01

independent, more heterogeneous group of patients (validation cohorts 2–5; 249 patients after excluding 37 patients with an infection likelihood of “possible”) gave an AUC of 0.89 (95% CI 0.85–0.93). Disease severity, as measured by Sequential Organ Failure Assessment (SOFA) score or Acute Physiology and Chronic Health Evaluation (APACHE) IV score, was not a significant confounding variable. The diagnostic utility of SeptiCyte Lab was evaluated by comparison to various clinical and laboratory parameters available to a clinician within 24 h of ICU admission. SeptiCyte Lab was significantly better at differentiating cases from controls than all tested parameters, both singly and in various logistic combinations, and more than halved the diagnostic error rate compared to procalcitonin in all tested cohorts and cohort combinations. Limitations of this study relate to (1) cohort compositions that do not perfectly reflect the composition of the intended use population, (2) potential biases that could be introduced as a result of the current lack of a gold standard for diagnosing sepsis, and (3) lack of a complete, unbiased comparison to C-reactive protein. Conclusions SeptiCyte Lab is a rapid molecular assay that may be clinically useful in managing ICU patients with systemic inflammation. Further study in population-based cohorts is needed to validate this assay for clinical use. PMID:26645559

Apparent and internal validity of a Monte Carlo-Markov model for cardiovascular disease in a cohort follow-up study.

PubMed

Nijhuis, Rogier L; Stijnen, Theo; Peeters, Anna; Witteman, Jacqueline C M; Hofman, Albert; Hunink, M G Myriam

2006-01-01

To determine the apparent and internal validity of the Rotterdam Ischemic heart disease & Stroke Computer (RISC) model, a Monte Carlo-Markov model, designed to evaluate the impact of cardiovascular disease (CVD) risk factors and their modification on life expectancy (LE) and cardiovascular disease-free LE (DFLE) in a general population (hereinafter, these will be referred to together as (DF)LE). The model is based on data from the Rotterdam Study, a cohort follow-up study of 6871 subjects aged 55 years and older who visited the research center for risk factor assessment at baseline (1990-1993) and completed a follow-up visit 7 years later (original cohort). The transition probabilities and risk factor trends used in the RISC model were based on data from 3501 subjects (the study cohort). To validate the RISC model, the number of simulated CVD events during 7 years' follow-up were compared with the observed number of events in the study cohort and the original cohort, respectively, and simulated (DF)LEs were compared with the (DF)LEs calculated from multistate life tables. Both in the study cohort and in the original cohort, the simulated distribution of CVD events was consistent with the observed number of events (CVD deaths: 7.1% v. 6.6% and 7.4% v. 7.6%, respectively; non-CVD deaths: 11.2% v. 11.5% and 12.9% v. 13.0%, respectively). The distribution of (DF)LEs estimated with the RISC model consistently encompassed the (DF)LEs calculated with multistate life tables. The simulated events and (DF)LE estimates from the RISC model are consistent with observed data from a cohort follow-up study.

Troponin-only Manchester Acute Coronary Syndromes (T-MACS) decision aid: single biomarker re-derivation and external validation in three cohorts

PubMed Central

Body, Richard; Sperrin, Matthew; Lewis, Philip S; Burrows, Gillian; Carley, Simon; McDowell, Garry; Buchan, Iain; Greaves, Kim; Mackway-Jones, Kevin

2017-01-01

Background The original Manchester Acute Coronary Syndromes model (MACS) ‘rules in’ and ‘rules out’ acute coronary syndromes (ACS) using high sensitivity cardiac troponin T (hs-cTnT) and heart-type fatty acid binding protein (H-FABP) measured at admission. The latter is not always available. We aimed to refine and validate MACS as Troponin-only Manchester Acute Coronary Syndromes (T-MACS), cutting down the biomarkers to just hs-cTnT. Methods We present secondary analyses from four prospective diagnostic cohort studies including patients presenting to the ED with suspected ACS. Data were collected and hs-cTnT measured on arrival. The primary outcome was ACS, defined as prevalent acute myocardial infarction (AMI) or incident death, AMI or coronary revascularisation within 30 days. T-MACS was built in one cohort (derivation set) and validated in three external cohorts (validation set). Results At the ‘rule out’ threshold, in the derivation set (n=703), T-MACS had 99.3% (95% CI 97.3% to 99.9%) negative predictive value (NPV) and 98.7% (95.3%–99.8%) sensitivity for ACS, ‘ruling out’ 37.7% patients (specificity 47.6%, positive predictive value (PPV) 34.0%). In the validation set (n=1459), T-MACS had 99.3% (98.3%–99.8%) NPV and 98.1% (95.2%–99.5%) sensitivity, ‘ruling out’ 40.4% (n=590) patients (specificity 47.0%, PPV 23.9%). T-MACS would ‘rule in’ 10.1% and 4.7% patients in the respective sets, of which 100.0% and 91.3% had ACS. C-statistics for the original and refined rules were similar (T-MACS 0.91 vs MACS 0.90 on validation). Conclusions T-MACS could ‘rule out’ ACS in 40% of patients, while ‘ruling in’ 5% at highest risk using a single hs-cTnT measurement on arrival. As a clinical decision aid, T-MACS could therefore help to conserve healthcare resources. PMID:27565197

Real-world effects of medications for chronic obstructive pulmonary disease: protocol for a UK population-based non-interventional cohort study with validation against randomised trial results.

PubMed

Wing, Kevin; Williamson, Elizabeth; Carpenter, James R; Wise, Lesley; Schneeweiss, Sebastian; Smeeth, Liam; Quint, Jennifer K; Douglas, Ian

2018-03-25

Chronic obstructive pulmonary disease (COPD) is a progressive disease affecting 3 million people in the UK, in which patients exhibit airflow obstruction that is not fully reversible. COPD treatment guidelines are largely informed by randomised controlled trial results, but it is unclear if these findings apply to large patient populations not studied in trials. Non-interventional studies could be used to study patient groups excluded from trials, but the use of these studies to estimate treatment effectiveness is in its infancy. In this study, we will use individual trial data to validate non-interventional methods for assessing COPD treatment effectiveness, before applying these methods to the analysis of treatment effectiveness within people excluded from, or under-represented in COPD trials. Using individual patient data from the landmark COPD Towards a Revolution in COPD Health (TORCH) trial and validated methods for detecting COPD and exacerbations in routinely collected primary care data, we will assemble a cohort in the UK Clinical Practice Research Datalink (selecting people between 1 January 2004 and 1 January 2017) with similar characteristics to TORCH participants and test whether non-interventional data can generate comparable results to trials, using cohort methodology with propensity score techniques to adjust for potential confounding. We will then use the methodological template we have developed to determine risks and benefits of COPD treatments in people excluded from TORCH. Outcomes are pneumonia, COPD exacerbation, mortality and time to treatment change. Groups to be studied include the elderly (>80 years), people with substantial comorbidity, people with and without underlying cardiovascular disease and people with mild COPD. Ethical approval has been granted by the London School of Hygiene & Tropical Medicine Ethics Committee (Ref: 11997). The study has been approved by the Independent Scientific Advisory Committee of the UK Medicines and

Prospective validation of pathologic complete response models in rectal cancer: Transferability and reproducibility.

PubMed

van Soest, Johan; Meldolesi, Elisa; van Stiphout, Ruud; Gatta, Roberto; Damiani, Andrea; Valentini, Vincenzo; Lambin, Philippe; Dekker, Andre

2017-09-01

Multiple models have been developed to predict pathologic complete response (pCR) in locally advanced rectal cancer patients. Unfortunately, validation of these models normally omit the implications of cohort differences on prediction model performance. In this work, we will perform a prospective validation of three pCR models, including information whether this validation will target transferability or reproducibility (cohort differences) of the given models. We applied a novel methodology, the cohort differences model, to predict whether a patient belongs to the training or to the validation cohort. If the cohort differences model performs well, it would suggest a large difference in cohort characteristics meaning we would validate the transferability of the model rather than reproducibility. We tested our method in a prospective validation of three existing models for pCR prediction in 154 patients. Our results showed a large difference between training and validation cohort for one of the three tested models [Area under the Receiver Operating Curve (AUC) cohort differences model: 0.85], signaling the validation leans towards transferability. Two out of three models had a lower AUC for validation (0.66 and 0.58), one model showed a higher AUC in the validation cohort (0.70). We have successfully applied a new methodology in the validation of three prediction models, which allows us to indicate if a validation targeted transferability (large differences between training/validation cohort) or reproducibility (small cohort differences). © 2017 American Association of Physicists in Medicine.

Predictive validity of the UK clinical aptitude test in the final years of medical school: a prospective cohort study

PubMed Central

2014-01-01

Background The UK Clinical Aptitude Test (UKCAT) was designed to address issues identified with traditional methods of selection. This study aims to examine the predictive validity of the UKCAT and compare this to traditional selection methods in the senior years of medical school. This was a follow-up study of two cohorts of students from two medical schools who had previously taken part in a study examining the predictive validity of the UKCAT in first year. Methods The sample consisted of 4th and 5th Year students who commenced their studies at the University of Aberdeen or University of Dundee medical schools in 2007. Data collected were: demographics (gender and age group), UKCAT scores; Universities and Colleges Admissions Service (UCAS) form scores; admission interview scores; Year 4 and 5 degree examination scores. Pearson’s correlations were used to examine the relationships between admissions variables, examination scores, gender and age group, and to select variables for multiple linear regression analysis to predict examination scores. Results Ninety-nine and 89 students at Aberdeen medical school from Years 4 and 5 respectively, and 51 Year 4 students in Dundee, were included in the analysis. Neither UCAS form nor interview scores were statistically significant predictors of examination performance. Conversely, the UKCAT yielded statistically significant validity coefficients between .24 and .36 in four of five assessments investigated. Multiple regression analysis showed the UKCAT made a statistically significant unique contribution to variance in examination performance in the senior years. Conclusions Results suggest the UKCAT appears to predict performance better in the later years of medical school compared to earlier years and provides modest supportive evidence for the UKCAT’s role in student selection within these institutions. Further research is needed to assess the predictive validity of the UKCAT against professional and behavioural

Use of a 17-Gene Prognostic Assay in Contemporary Urologic Practice: Results of an Interim Analysis in an Observational Cohort.

PubMed

Eure, Gregg; Germany, Raymond; Given, Robert; Lu, Ruixiao; Shindel, Alan W; Rothney, Megan; Glowacki, Richard; Henderson, Jonathan; Richardson, Tim; Goldfischer, Evan; Febbo, Phillip G; Denes, Bela S

2017-09-01

To study the impact of genomic testing in shared decision making for men with clinically low-risk prostate cancer (PCa). Patients with clinically low-risk PCa were enrolled in a prospective, multi-institutional study of a validated 17-gene tissue-based reverse transcription polymerase chain reaction assay (Genomic Prostate Score [GPS]). In this paper we report on outcomes in the first 297 patients enrolled in the study with valid 17-gene assay results and decision-change data. The primary end points were shared decision on initial management and persistence on active surveillance (AS) at 1 year post diagnosis. AS utilization and persistence were compared with similar end points in a group of patients who did not have genomic testing (baseline cohort). Secondary end points included perceived utility of the assay and patient decisional conflict before and after testing. One-year results were available on 258 patients. Shift between initial recommendation and shared decision occurred in 23% of patients. Utilization of AS was higher in the GPS-tested cohort than in the untested baseline cohort (62% vs 40%). The proportion of men who selected and persisted on AS at 1 year was 55% and 34% in the GPS and baseline cohorts, respectively. Physicians reported that GPS was useful in 90% of cases. Mean decisional conflict scores declined in patients after GPS testing. Patients who received GPS testing were more likely to select and persist on AS for initial management compared with a matched baseline group. These data indicate that GPS help guide shared decisions in clinically low-risk PCa. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

A new model of wheezing severity in young children using the validated ISAAC wheezing module: A latent variable approach with validation in independent cohorts.

PubMed

Brunwasser, Steven M; Gebretsadik, Tebeb; Gold, Diane R; Turi, Kedir N; Stone, Cosby A; Datta, Soma; Gern, James E; Hartert, Tina V

2018-01-01

The International Study of Asthma and Allergies in Children (ISAAC) Wheezing Module is commonly used to characterize pediatric asthma in epidemiological studies, including nearly all airway cohorts participating in the Environmental Influences on Child Health Outcomes (ECHO) consortium. However, there is no consensus model for operationalizing wheezing severity with this instrument in explanatory research studies. Severity is typically measured using coarsely-defined categorical variables, reducing power and potentially underestimating etiological associations. More precise measurement approaches could improve testing of etiological theories of wheezing illness. We evaluated a continuous latent variable model of pediatric wheezing severity based on four ISAAC Wheezing Module items. Analyses included subgroups of children from three independent cohorts whose parents reported past wheezing: infants ages 0-2 in the INSPIRE birth cohort study (Cohort 1; n = 657), 6-7-year-old North American children from Phase One of the ISAAC study (Cohort 2; n = 2,765), and 5-6-year-old children in the EHAAS birth cohort study (Cohort 3; n = 102). Models were estimated using structural equation modeling. In all cohorts, covariance patterns implied by the latent variable model were consistent with the observed data, as indicated by non-significant χ2 goodness of fit tests (no evidence of model misspecification). Cohort 1 analyses showed that the latent factor structure was stable across time points and child sexes. In both cohorts 1 and 3, the latent wheezing severity variable was prospectively associated with wheeze-related clinical outcomes, including physician asthma diagnosis, acute corticosteroid use, and wheeze-related outpatient medical visits when adjusting for confounders. We developed an easily applicable continuous latent variable model of pediatric wheezing severity based on items from the well-validated ISAAC Wheezing Module. This model prospectively associates with

Coffee, caffeine, and risk of completed suicide: results from 3 prospective cohorts of American adults

PubMed Central

Lucas, Michel; O’Reilly, Eilis J.; Pan, An; Mirzaei, Fariba; Willett, Walter C.; Okereke, Olivia I.; Ascherio, Alberto

2014-01-01

Objective To evaluate the association between coffee and caffeine consumption and suicide risk in three large-scale cohorts of U.S. men and women. Methods We accessed data of 43,599 men enrolled in the Health Professionals Follow-up Study (HPFS, 1988–2008), 73,820 women in the Nurses’ Health Study (NHS, 1992–2008), and 91,005 women in the NHS II (1993–2007). Consumption of caffeine, coffee, and decaffeinated coffee, was assessed every four years by validated food-frequency questionnaires. Deaths from suicide were determined by physician review of death certificates. Multivariate adjusted relative risks (RRs) were estimated with Cox proportional hazard models. Cohort specific RRs were pooled using random-effect models. Results We documented 277 deaths from suicide. Compared to those consuming ≤1 cup/week of caffeinated coffee (≤8 oz/237 ml), the pooled multivariate RR (95% confidence interval [CI]) of suicide was 0.55 (0.38–0.78) for those consuming 2–3 cups/day and 0.47 (0.27–0.81) for those consuming ≥4 cups/day (P trend <0.001). The pooled multivariate RR (95% CI) for suicide was 0.75 (0.63–0.90) for each increment of 2 cups/day of caffeinated coffee and 0.77 (0.63–0.93) for each increment of 300 mg/day of caffeine. Conclusions These results from three large cohorts support an association between caffeine consumption and lower risk of suicide. PMID:23819683

Development and validation of a gene expression-based signature to predict distant metastasis in locoregionally advanced nasopharyngeal carcinoma: a retrospective, multicentre, cohort study.

PubMed

Tang, Xin-Ran; Li, Ying-Qin; Liang, Shao-Bo; Jiang, Wei; Liu, Fang; Ge, Wen-Xiu; Tang, Ling-Long; Mao, Yan-Ping; He, Qing-Mei; Yang, Xiao-Jing; Zhang, Yuan; Wen, Xin; Zhang, Jian; Wang, Ya-Qin; Zhang, Pan-Pan; Sun, Ying; Yun, Jing-Ping; Zeng, Jing; Li, Li; Liu, Li-Zhi; Liu, Na; Ma, Jun

2018-03-01

Gene expression patterns can be used as prognostic biomarkers in various types of cancers. We aimed to identify a gene expression pattern for individual distant metastatic risk assessment in patients with locoregionally advanced nasopharyngeal carcinoma. In this multicentre, retrospective, cohort analysis, we included 937 patients with locoregionally advanced nasopharyngeal carcinoma from three Chinese hospitals: the Sun Yat-sen University Cancer Center (Guangzhou, China), the Affiliated Hospital of Guilin Medical University (Guilin, China), and the First People's Hospital of Foshan (Foshan, China). Using microarray analysis, we profiled mRNA gene expression between 24 paired locoregionally advanced nasopharyngeal carcinoma tumours from patients at Sun Yat-sen University Cancer Center with or without distant metastasis after radical treatment. Differentially expressed genes were examined using digital expression profiling in a training cohort (Guangzhou training cohort; n=410) to build a gene classifier using a penalised regression model. We validated the prognostic accuracy of this gene classifier in an internal validation cohort (Guangzhou internal validation cohort, n=204) and two external independent cohorts (Guilin cohort, n=165; Foshan cohort, n=158). The primary endpoint was distant metastasis-free survival. Secondary endpoints were disease-free survival and overall survival. We identified 137 differentially expressed genes between metastatic and non-metastatic locoregionally advanced nasopharyngeal carcinoma tissues. A distant metastasis gene signature for locoregionally advanced nasopharyngeal carcinoma (DMGN) that consisted of 13 genes was generated to classify patients into high-risk and low-risk groups in the training cohort. Patients with high-risk scores in the training cohort had shorter distant metastasis-free survival (hazard ratio [HR] 4·93, 95% CI 2·99-8·16; p<0·0001), disease-free survival (HR 3·51, 2·43-5·07; p<0·0001), and overall

Dietary trace element intake and liver cancer risk: Results from two population-based cohorts in China.

PubMed

Ma, Xiao; Yang, Yang; Li, Hong-Lan; Zheng, Wei; Gao, Jing; Zhang, Wei; Yang, Gong; Shu, Xiao-Ou; Xiang, Yong-Bing

2017-03-01

Dietary factors have been hypothesized to affect the risk of liver cancer via various mechanisms, but the influence has been not well studied and the evidence is conflicting. We investigated associations of dietary trace element intake, assessed through a validated food frequency questionnaire, with risk of liver cancer in two prospective cohort studies of 132,765 women (1997-2013) and men (2002-2013) in Shanghai, China. The associations were first evaluated in cohort studies and further assessed in a case-control study nested within these cohorts adjusting for hepatitis B virus infection. For cohort analyses, Cox proportional hazard models were used to estimate hazard ratios and 95% confidence intervals. For nested case-control analyses, conditional logistic regression was used to calculate odds ratios and 95% confidence intervals. After a median follow-up time of 15.2 years for the Shanghai Women's Health Study and 9.3 years for the Shanghai Men's Health Study, 192 women and 344 men developed liver cancer. Dietary intake of manganese was inversely associated with liver cancer risk (highest vs. lowest quintile, HR = 0.51, 95% CI: 0.35-0.73; p trend  = 0.001). Further adjustment for hepatitis B virus infection in the nested case-control study yielded a similar result (highest vs. lowest quintile, OR = 0.38, 95% CI: 0.21-0.69; p trend  < 0.001). No significant association was found between dietary intake of selenium, iron, zinc, copper and liver cancer risk. The results suggest that higher intake of manganese may be associated with a lower risk of liver cancer in China. © 2016 UICC.

New Zealand Diabetes Cohort Study cardiovascular risk score for people with Type 2 diabetes: validation in the PREDICT cohort.

PubMed

Robinson, Tom; Elley, C Raina; Wells, Sue; Robinson, Elizabeth; Kenealy, Tim; Pylypchuk, Romana; Bramley, Dale; Arroll, Bruce; Crengle, Sue; Riddell, Tania; Ameratunga, Shanthi; Metcalf, Patricia; Drury, Paul L

2012-09-01

New Zealand (NZ) guidelines recommend treating people for cardiovascular disease (CVD) risk on the basis of five-year absolute risk using a NZ adaptation of the Framingham risk equation. A diabetes-specific Diabetes Cohort Study (DCS) CVD predictive risk model has been developed and validated using NZ Get Checked data. To revalidate the DCS model with an independent cohort of people routinely assessed using PREDICT, a web-based CVD risk assessment and management programme. People with Type 2 diabetes without pre-existing CVD were identified amongst people who had a PREDICT risk assessment between 2002 and 2005. From this group we identified those with sufficient data to allow estimation of CVD risk with the DCS models. We compared the DCS models with the NZ Framingham risk equation in terms of discrimination, calibration, and reclassification implications. Of 3044 people in our study cohort, 1829 people had complete data and therefore had CVD risks calculated. Of this group, 12.8% (235) had a cardiovascular event during the five-year follow-up. The DCS models had better discrimination than the currently used equation, with C-statistics being 0.68 for the two DCS models and 0.65 for the NZ Framingham model. The DCS models were superior to the NZ Framingham equation at discriminating people with diabetes who will have a cardiovascular event. The adoption of a DCS model would lead to a small increase in the number of people with diabetes who are treated with medication, but potentially more CVD events would be avoided.

Coffee, caffeine, and risk of completed suicide: results from three prospective cohorts of American adults.

PubMed

Lucas, Michel; O'Reilly, Eilis J; Pan, An; Mirzaei, Fariba; Willett, Walter C; Okereke, Olivia I; Ascherio, Alberto

2014-07-01

To evaluate the association between coffee and caffeine consumption and suicide risk in three large-scale cohorts of US men and women. We accessed data of 43,599 men enrolled in the Health Professionals Follow-up Study (HPFS, 1988-2008), 73,820 women in the Nurses' Health Study (NHS, 1992-2008), and 91,005 women in the NHS II (1993-2007). Consumption of caffeine, coffee, and decaffeinated coffee, was assessed every 4 years by validated food-frequency questionnaires. Deaths from suicide were determined by physician review of death certificates. Multivariate adjusted relative risks (RRs) were estimated with Cox proportional hazard models. Cohort specific RRs were pooled using random-effect models. We documented 277 deaths from suicide. Compared to those consuming ≤ 1 cup/week of caffeinated coffee (< 8 oz/237 ml), the pooled multivariate RR (95% confidence interval [CI]) of suicide was 0.55 (0.38-0.78) for those consuming 2-3 cups/day and 0.47 (0.27-0.81) for those consuming ≥ 4 cups/day (P trend < 0.001). The pooled multivariate RR (95% CI) for suicide was 0.75 (0.63-0.90) for each increment of 2 cups/day of caffeinated coffee and 0.77 (0.63-0.93) for each increment of 300 mg/day of caffeine. These results from three large cohorts support an association between caffeine consumption and lower risk of suicide.

Predictive validity of the UK clinical aptitude test in the final years of medical school: a prospective cohort study.

PubMed

Husbands, Adrian; Mathieson, Alistair; Dowell, Jonathan; Cleland, Jennifer; MacKenzie, Rhoda

2014-04-23

The UK Clinical Aptitude Test (UKCAT) was designed to address issues identified with traditional methods of selection. This study aims to examine the predictive validity of the UKCAT and compare this to traditional selection methods in the senior years of medical school. This was a follow-up study of two cohorts of students from two medical schools who had previously taken part in a study examining the predictive validity of the UKCAT in first year. The sample consisted of 4th and 5th Year students who commenced their studies at the University of Aberdeen or University of Dundee medical schools in 2007. Data collected were: demographics (gender and age group), UKCAT scores; Universities and Colleges Admissions Service (UCAS) form scores; admission interview scores; Year 4 and 5 degree examination scores. Pearson's correlations were used to examine the relationships between admissions variables, examination scores, gender and age group, and to select variables for multiple linear regression analysis to predict examination scores. Ninety-nine and 89 students at Aberdeen medical school from Years 4 and 5 respectively, and 51 Year 4 students in Dundee, were included in the analysis. Neither UCAS form nor interview scores were statistically significant predictors of examination performance. Conversely, the UKCAT yielded statistically significant validity coefficients between .24 and .36 in four of five assessments investigated. Multiple regression analysis showed the UKCAT made a statistically significant unique contribution to variance in examination performance in the senior years. Results suggest the UKCAT appears to predict performance better in the later years of medical school compared to earlier years and provides modest supportive evidence for the UKCAT's role in student selection within these institutions. Further research is needed to assess the predictive validity of the UKCAT against professional and behavioural outcomes as the cohort commences working life.

Development and validation of a clinical prediction rule to identify suspected breast cancer: a prospective cohort study.

PubMed

Galvin, Rose; Joyce, Doireann; Downey, Eithne; Boland, Fiona; Fahey, Tom; Hill, Arnold K

2014-10-03

The number of primary care referrals of women with breast symptoms to symptomatic breast units (SBUs) has increased exponentially in the past decade in Ireland. The aim of this study is to develop and validate a clinical prediction rule (CPR) to identify women with breast cancer so that a more evidence based approach to referral from primary care to these SBUs can be developed. We analysed routine data from a prospective cohort of consecutive women reviewed at a SBU with breast symptoms. The dataset was split into a derivation and validation cohort. Regression analysis was used to derive a CPR from the patient's history and clinical findings. Validation of the CPR consisted of estimating the number of breast cancers predicted to occur compared with the actual number of observed breast cancers across deciles of risk. A total of 6,590 patients were included in the derivation study and 4.9% were diagnosed with breast cancer. Independent clinical predictors for breast cancer were: increasing age by year (adjusted odds ratio 1.08, 95% CI 1.07-1.09); presence of a lump (5.63, 95% CI 4.2-7.56); nipple change (2.77, 95% CI 1.68-4.58) and nipple discharge (2.09, 95% CI 1.1-3.97). Validation of the rule (n = 911) demonstrated that the probability of breast cancer was higher with an increasing number of these independent variables. The Hosmer-Lemeshow goodness of fit showed no overall significant difference between the expected and the observed numbers of breast cancer (χ(2)HL: 6.74, p-value: 0.56). This study derived and validated a CPR for breast cancer in women attending an Irish national SBU. We found that increasing age, presence of a lump, nipple discharge and nipple change are all associated with increased risk of breast cancer. Further validation of the rule is necessary as well as an assessment of its impact on referral practice.

Validation of the first peoples cultural capability measurement tool with undergraduate health students: A descriptive cohort study.

PubMed

West, Roianne; Mills, Kyly; Rowland, Dale; Creedy, Debra K

2018-05-01

Health professional graduates require the capacity to work safely, both clinically and culturally, when delivering care to Indigenous peoples worldwide. In the Australian context, the Aboriginal and Torres Strait Islander Health Curriculum Framework (The Framework) provides guidance for health professional programs to integrate, teach and assess Aboriginal and Torres Strait Islander peoples' (First Peoples) health content. There is, however, a lack of validated tools that measure the development of students' cultural capabilities. To validate the Cultural Capability Measurement Tool with a cohort of health professional students. A descriptive cohort design was used. All students (N = 753) enrolled in a discrete First Peoples Health course at an Australian university were invited to complete the Cultural Capability Measurement Tool. The tool was tested for reliability, content and construct validity using confirmatory factor analysis; and concurrent validity using and the Cultural Understanding Self-Assessment Tool. A sample of 418 (73% response rate) was recruited. Most participants were enrolled in the Bachelor of Nursing program (n = 369, 82%). The Cultural Capability Measurement Tool had a Cronbach's alpha coefficient of 0.86. A five-factor solution was confirmed which reflected the cultural capability domains and accounted for 51% of the variance. Scores correlated with students' cultural understanding (r = 0.28, p < 0.001). Successful implementation of The Framework requires instruments to measure changes in students' cultural capabilities. Measuring nursing students' cultural capabilities can inform their development, identify areas of strengths and deficits for educators, and will ultimately contribute to the development of a culturally safe nursing workforce. Copyright © 2018 Elsevier Ltd. All rights reserved.

Development of the Galaxy Chronic Obstructive Pulmonary Disease (COPD) Model Using Data from ECLIPSE: Internal Validation of a Linked-Equations Cohort Model.

PubMed

Briggs, Andrew H; Baker, Timothy; Risebrough, Nancy A; Chambers, Mike; Gonzalez-McQuire, Sebastian; Ismaila, Afisi S; Exuzides, Alex; Colby, Chris; Tabberer, Maggie; Muellerova, Hana; Locantore, Nicholas; Rutten van Mölken, Maureen P M H; Lomas, David A

2017-05-01

The recent joint International Society for Pharmacoeconomics and Outcomes Research / Society for Medical Decision Making Modeling Good Research Practices Task Force emphasized the importance of conceptualizing and validating models. We report a new model of chronic obstructive pulmonary disease (COPD) (part of the Galaxy project) founded on a conceptual model, implemented using a novel linked-equation approach, and internally validated. An expert panel developed a conceptual model including causal relationships between disease attributes, progression, and final outcomes. Risk equations describing these relationships were estimated using data from the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) study, with costs estimated from the TOwards a Revolution in COPD Health (TORCH) study. Implementation as a linked-equation model enabled direct estimation of health service costs and quality-adjusted life years (QALYs) for COPD patients over their lifetimes. Internal validation compared 3 years of predicted cohort experience with ECLIPSE results. At 3 years, the Galaxy COPD model predictions of annual exacerbation rate and annual decline in forced expiratory volume in 1 second fell within the ECLIPSE data confidence limits, although 3-year overall survival was outside the observed confidence limits. Projections of the risk equations over time permitted extrapolation to patient lifetimes. Averaging the predicted cost/QALY outcomes for the different patients within the ECLIPSE cohort gives an estimated lifetime cost of £25,214 (undiscounted)/£20,318 (discounted) and lifetime QALYs of 6.45 (undiscounted/5.24 [discounted]) per ECLIPSE patient. A new form of model for COPD was conceptualized, implemented, and internally validated, based on a series of linked equations using epidemiological data (ECLIPSE) and cost data (TORCH). This Galaxy model predicts COPD outcomes from treatment effects on disease attributes such as lung function

External validation of a prediction model for surgical site infection after thoracolumbar spine surgery in a Western European cohort.

PubMed

Janssen, Daniël M C; van Kuijk, Sander M J; d'Aumerie, Boudewijn B; Willems, Paul C

2018-05-16

A prediction model for surgical site infection (SSI) after spine surgery was developed in 2014 by Lee et al. This model was developed to compute an individual estimate of the probability of SSI after spine surgery based on the patient's comorbidity profile and invasiveness of surgery. Before any prediction model can be validly implemented in daily medical practice, it should be externally validated to assess how the prediction model performs in patients sampled independently from the derivation cohort. We included 898 consecutive patients who underwent instrumented thoracolumbar spine surgery. To quantify overall performance using Nagelkerke's R 2 statistic, the discriminative ability was quantified as the area under the receiver operating characteristic curve (AUC). We computed the calibration slope of the calibration plot, to judge prediction accuracy. Sixty patients developed an SSI. The overall performance of the prediction model in our population was poor: Nagelkerke's R 2 was 0.01. The AUC was 0.61 (95% confidence interval (CI) 0.54-0.68). The estimated slope of the calibration plot was 0.52. The previously published prediction model showed poor performance in our academic external validation cohort. To predict SSI after instrumented thoracolumbar spine surgery for the present population, a better fitting prediction model should be developed.

Prospective, Multicenter Validation Study of Magnetic Resonance Volumetry for Response Assessment After Preoperative Chemoradiation in Rectal Cancer: Can the Results in the Literature be Reproduced?

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

Martens, Milou H., E-mail: mh.martens@hotmail.com; Department of Surgery, Maastricht University Medical Center, Maastricht; GROW School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht

2015-12-01

Purpose: To review the available literature on tumor size/volume measurements on magnetic resonance imaging for response assessment after chemoradiotherapy, and validate these cut-offs in an independent multicenter patient cohort. Methods and Materials: The study included 2 parts. (1) Review of the literature: articles were included that assessed the accuracy of tumor size/volume measurements on magnetic resonance imaging for tumor response assessment. Size/volume cut-offs were extracted; (2) Multicenter validation: extracted cut-offs from the literature were tested in a multicenter cohort (n=146). Accuracies were calculated and compared with reported results from the literature. Results: The review included 14 articles, in which 3more » different measurement methods were assessed: (1) tumor length; (2) 3-dimensonial tumor size; and (3) whole volume. Study outcomes consisted of (1) complete response (ypT0) versus residual tumor; (2) tumor regression grade 1 to 2 versus 3 to 5; and (3) T-downstaging (ypT« less

Mortality in the cotton industry workers: results of a cohort study.

PubMed

Szeszenia-Dabrowska, N; Wilczyńska, U; Strzelecka, A; Sobala, W

1999-01-01

The cohort consisted of persons found on the payroll of one of the Lódź cotton plants in 1964-1993 who were employed in the plant for at least 10 years. Death risk by causes was analysed using standardised mortality ratios (SMRs) calculated by the person-years method. The general population of Poland was used as the reference. In all, 7892 people were observed. As of December 31, 1995, the follow-up was completed for 7545 people (2852 men and 4693 women), i.e. the availability of the cohort was 95.6%. A total of 2069 deaths were recorded; the information on the cause of death was available for 97% of the subjects. In the male cohort, the level of the general mortality was the same as in the general population (SMR = 99). However, there was a significant increase in the number of deaths from diseases of the digestive system (SMR = 142) and larynx cancer (SMR = 188). The analysis of the results by production departments revealed in the weaving department significantly higher mortality from atherosclerosis (SMR = 141), peritoneal carcinoma (SMR = 1057) and melanoma (SMR = 677); and in the spinning department the increased risk of the hypertensive disease (SMR = 239), atherosclerosis (SMR = 175), and Hodgkin's disease (SMR = 768). Mortality in the female cohort was lower than that in the general population (SMR = 88). None of the disease groups or tumour sites caused statistically significant excess deaths either in the total cohort or in subcohorts selected according to departments. Special attention was paid to the chemical processing departments where chemicals used could contribute to the increased risk of death from cancer. Our analysis did not reveal any significant increase either in the total cohort of the workers employed in those departments or in the cohorts analyzed by duration of employment. Our results confirm the lower risk of lung cancer in the analysed group as compared with that in the general population. The numerous, but statistically

Anthrax vaccination in the Millennium Cohort: validation and measures of health.

PubMed

Smith, Besa; Leard, Cynthia A; Smith, Tyler C; Reed, Robert J; Ryan, Margaret A K

2007-04-01

In 1998, the United States Department of Defense initiated the Anthrax Vaccine Immunization Program. Concerns about vaccine-related adverse health effects followed, prompting several studies. Although some studies used self-reported vaccination data, the reliability of such data has not been established. The purpose of this study was to compare self-reported anthrax vaccination to electronic vaccine records among a large military cohort and to evaluate the relationship between vaccine history and health outcome data. Between September 2005 and February 2006 self-reported anthrax vaccination was compared to electronic records for 67,018 participants enrolled in the Millennium Cohort Study between 2001 and 2003 using kappa statistics. Multivariable modeling investigated vaccination concordance as it pertains to subjective health (functional status) and objective health (hospitalization) metrics. Greater than substantial agreement (kappa=0.80) was found between self-report and electronic recording of anthrax vaccination. Of all participants with electronic documentation of anthrax vaccination, 98% self-reported being vaccinated; and of all participants with no electronic record of vaccination, 90% self-reported not receiving a vaccination. There were no differences between vaccinated and unvaccinated participants in overall measures of health. Only the subset of participants who self-reported anthrax vaccination, but had no electronic confirmation, differed from others in the cohort, with consistently lower measures of health as indicated by Medical Outcomes Study 36-Item Short Form Health Survey for Veterans (SF-36V) scores. These results indicate that military members accurately recall their anthrax vaccinations. Results also suggest that anthrax vaccination among Millennium Cohort participants is not associated with self-reported health problems or broad measures of health problems severe enough to require hospitalization. Service members who self

[Validity of self-reported metabolic syndrome components in a cohort study].

PubMed

Fernández-Montero, Alejandro; Beunza, Juan J; Bes-Rastrollo, Maira; Barrio, María T; de la Fuente-Arrillaga, Carmen; Moreno-Galarraga, Laura; Martínez-González, Miguel A

2011-01-01

To assess the accuracy of self-reported data needed to constitute the metabolic syndrome in the University of Navarra Follow-Up [Seguimiento Universidad de Navarra (SUN)] cohort. The SUN project is a multi-purpose prospective cohort, formed by more than 20,000 university graduates, followed-up using surface mail questionnaires every 2 years. In a sample of 287 cohort participants, self-reported data on the criteria needed to define the metabolic syndrome (waist circumference, blood pressure, triglycerides, high-density lipoprotein-cholesterol and glucose) were compared with the same biometric data obtained by blood tests or measured by trained medical staff. Intra-class correlation coefficients with 95% confidence intervals (95% CI), relative mean error and agreement limits according to the method proposed by Bland and Altman were calculated for each variable studied. High intraclass correlations were found for the values of waist circumference (r=0.86, 95% CI: 0.80-0.90) and triglycerides (r=0.71, 95%CI: 0.61-0.79). Moderate intraclass correlations were found (between 0.46 and 0.63) for the other factors. Relative mean errors were always<2.5%, and >91% of values were within the limits of agreement for all variables. The results suggest that self-declared data on the criteria of metabolic syndrome obtained in the SUN cohort, though with some caution, are sufficiently accurate to be used in epidemiological studies. Copyright © 2010 SESPAS. Published by Elsevier Espana. All rights reserved.

Cohort profile: cerebral palsy in the Norwegian and Danish birth cohorts (MOBAND-CP)

PubMed Central

Tollånes, Mette C; Strandberg-Larsen, Katrine; Forthun, Ingeborg; Petersen, Tanja Gram; Moster, Dag; Andersen, Anne-Marie Nybo; Stoltenberg, Camilla; Olsen, Jørn; Wilcox, Allen J

2016-01-01

Purpose The purpose of MOthers and BAbies in Norway and Denmark cerebral palsy (MOBAND-CP) was to study CP aetiology in a prospective design. Participants MOBAND-CP is a cohort of more than 210 000 children, created as a collaboration between the world's two largest pregnancy cohorts—the Norwegian Mother and Child Cohort study (MoBa) and the Danish National Birth Cohort. MOBAND-CP includes maternal interview/questionnaire data collected during pregnancy and follow-up, plus linked information from national health registries. Findings to date Initial harmonisation of data from the 2 cohorts has created 140 variables for children and their mothers. In the MOBAND-CP cohort, 438 children with CP have been identified through record linkage with validated national registries, providing by far the largest such sample with prospectively collected detailed pregnancy data. Several studies investigating various hypotheses regarding CP aetiology are currently on-going. Future plans Additional data can be harmonised as necessary to meet requirements of new projects. Biological specimens collected during pregnancy and at delivery are potentially available for assay, as are results from assays conducted on these specimens for other projects. The study size allows consideration of CP subtypes, which is rare in aetiological studies of CP. In addition, MOBAND-CP provides a platform within the context of a merged birth cohort of exceptional size that could, after appropriate permissions have been sought, be used for cohort and case-cohort studies of other relatively rare health conditions of infants and children. PMID:27591025

Lung Cancer Risk Prediction Model Incorporating Lung Function: Development and Validation in the UK Biobank Prospective Cohort Study.

PubMed

Muller, David C; Johansson, Mattias; Brennan, Paul

2017-03-10

Purpose Several lung cancer risk prediction models have been developed, but none to date have assessed the predictive ability of lung function in a population-based cohort. We sought to develop and internally validate a model incorporating lung function using data from the UK Biobank prospective cohort study. Methods This analysis included 502,321 participants without a previous diagnosis of lung cancer, predominantly between 40 and 70 years of age. We used flexible parametric survival models to estimate the 2-year probability of lung cancer, accounting for the competing risk of death. Models included predictors previously shown to be associated with lung cancer risk, including sex, variables related to smoking history and nicotine addiction, medical history, family history of lung cancer, and lung function (forced expiratory volume in 1 second [FEV1]). Results During accumulated follow-up of 1,469,518 person-years, there were 738 lung cancer diagnoses. A model incorporating all predictors had excellent discrimination (concordance (c)-statistic [95% CI] = 0.85 [0.82 to 0.87]). Internal validation suggested that the model will discriminate well when applied to new data (optimism-corrected c-statistic = 0.84). The full model, including FEV1, also had modestly superior discriminatory power than one that was designed solely on the basis of questionnaire variables (c-statistic = 0.84 [0.82 to 0.86]; optimism-corrected c-statistic = 0.83; p FEV1 = 3.4 × 10 -13 ). The full model had better discrimination than standard lung cancer screening eligibility criteria (c-statistic = 0.66 [0.64 to 0.69]). Conclusion A risk prediction model that includes lung function has strong predictive ability, which could improve eligibility criteria for lung cancer screening programs.

Cohort profile: cerebral palsy in the Norwegian and Danish birth cohorts (MOBAND-CP).

PubMed

Tollånes, Mette C; Strandberg-Larsen, Katrine; Forthun, Ingeborg; Petersen, Tanja Gram; Moster, Dag; Andersen, Anne-Marie Nybo; Stoltenberg, Camilla; Olsen, Jørn; Wilcox, Allen J

2016-09-02

The purpose of MOthers and BAbies in Norway and Denmark cerebral palsy (MOBAND-CP) was to study CP aetiology in a prospective design. MOBAND-CP is a cohort of more than 210 000 children, created as a collaboration between the world's two largest pregnancy cohorts-the Norwegian Mother and Child Cohort study (MoBa) and the Danish National Birth Cohort. MOBAND-CP includes maternal interview/questionnaire data collected during pregnancy and follow-up, plus linked information from national health registries. Initial harmonisation of data from the 2 cohorts has created 140 variables for children and their mothers. In the MOBAND-CP cohort, 438 children with CP have been identified through record linkage with validated national registries, providing by far the largest such sample with prospectively collected detailed pregnancy data. Several studies investigating various hypotheses regarding CP aetiology are currently on-going. Additional data can be harmonised as necessary to meet requirements of new projects. Biological specimens collected during pregnancy and at delivery are potentially available for assay, as are results from assays conducted on these specimens for other projects. The study size allows consideration of CP subtypes, which is rare in aetiological studies of CP. In addition, MOBAND-CP provides a platform within the context of a merged birth cohort of exceptional size that could, after appropriate permissions have been sought, be used for cohort and case-cohort studies of other relatively rare health conditions of infants and children. 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/

Development and External Validation of the Korean Prostate Cancer Risk Calculator for High-Grade Prostate Cancer: Comparison with Two Western Risk Calculators in an Asian Cohort

PubMed Central

Yoon, Sungroh; Park, Man Sik; Choi, Hoon; Bae, Jae Hyun; Moon, Du Geon; Hong, Sung Kyu; Lee, Sang Eun; Park, Chanwang

2017-01-01

Purpose We developed the Korean Prostate Cancer Risk Calculator for High-Grade Prostate Cancer (KPCRC-HG) that predicts the probability of prostate cancer (PC) of Gleason score 7 or higher at the initial prostate biopsy in a Korean cohort (http://acl.snu.ac.kr/PCRC/RISC/). In addition, KPCRC-HG was validated and compared with internet-based Western risk calculators in a validation cohort. Materials and Methods Using a logistic regression model, KPCRC-HG was developed based on the data from 602 previously unscreened Korean men who underwent initial prostate biopsies. Using 2,313 cases in a validation cohort, KPCRC-HG was compared with the European Randomized Study of Screening for PC Risk Calculator for high-grade cancer (ERSPCRC-HG) and the Prostate Cancer Prevention Trial Risk Calculator 2.0 for high-grade cancer (PCPTRC-HG). The predictive accuracy was assessed using the area under the receiver operating characteristic curve (AUC) and calibration plots. Results PC was detected in 172 (28.6%) men, 120 (19.9%) of whom had PC of Gleason score 7 or higher. Independent predictors included prostate-specific antigen levels, digital rectal examination findings, transrectal ultrasound findings, and prostate volume. The AUC of the KPCRC-HG (0.84) was higher than that of the PCPTRC-HG (0.79, p<0.001) but not different from that of the ERSPCRC-HG (0.83) on external validation. Calibration plots also revealed better performance of KPCRC-HG and ERSPCRC-HG than that of PCPTRC-HG on external validation. At a cut-off of 5% for KPCRC-HG, 253 of the 2,313 men (11%) would not have been biopsied, and 14 of the 614 PC cases with Gleason score 7 or higher (2%) would not have been diagnosed. Conclusions KPCRC-HG is the first web-based high-grade prostate cancer prediction model in Korea. It had higher predictive accuracy than PCPTRC-HG in a Korean population and showed similar performance with ERSPCRC-HG in a Korean population. This prediction model could help avoid unnecessary biopsy

A comparison of the results of prospective and retrospective cohort studies in the field of digestive surgery.

PubMed

Ukai, Tomohiko; Shikata, Satoru; Nakayama, Takeo; Takemura, Yousuke C

2017-07-01

We compared the results of prospective and retrospective cohort studies in the field of digestive surgery to clarify whether the results of prospective cohort studies were more similar to those of randomized controlled trials (RCTs). We conducted a secondary analysis of the results to compare the results of RCTs with those of cohort studies in meta-analyses of 18 digestive surgical topics. The data from the prospective and retrospective cohort studies were combined. The summary estimates of each design were compared with those of RCTs. We used the Z score to investigate discrepancies. Twenty-nine outcomes of 11 topics were investigated in 289 cohort studies (prospective, n = 69; retrospective, n = 220). These were compared with the outcomes of 123 RCTs. In comparison to retrospective studies, the summary estimates of the prospective cohort studies were more similar to those of the RCTs [19/29 (prospective) vs. 10/29 (retrospective), P = 0.035). Five of the 29 outcomes of prospective studies and 6 of 29 outcomes of retrospective studies (P = 0.99) showed significant discrepancies in comparison to RCTs. In the digestive surgical field, the results of prospective cohort studies tended to be more similar to those of RCTs than retrospective studies; however, there were no significant discrepancies between the two types of cohort study.

Predicting Blunt Cerebrovascular Injury in Pediatric Trauma: Validation of the “Utah Score”

PubMed Central

Ravindra, Vijay M.; Bollo, Robert J.; Sivakumar, Walavan; Akbari, Hassan; Naftel, Robert P.; Limbrick, David D.; Jea, Andrew; Gannon, Stephen; Shannon, Chevis; Birkas, Yekaterina; Yang, George L.; Prather, Colin T.; Kestle, John R.

2017-01-01

Abstract Risk factors for blunt cerebrovascular injury (BCVI) may differ between children and adults, suggesting that children at low risk for BCVI after trauma receive unnecessary computed tomography angiography (CTA) and high-dose radiation. We previously developed a score for predicting pediatric BCVI based on retrospective cohort analysis. Our objective is to externally validate this prediction score with a retrospective multi-institutional cohort. We included patients who underwent CTA for traumatic cranial injury at four pediatric Level I trauma centers. Each patient in the validation cohort was scored using the “Utah Score” and classified as high or low risk. Before analysis, we defined a misclassification rate <25% as validating the Utah Score. Six hundred forty-five patients (mean age 8.6 ± 5.4 years; 63.4% males) underwent screening for BCVI via CTA. The validation cohort was 411 patients from three sites compared with the training cohort of 234 patients. Twenty-two BCVIs (5.4%) were identified in the validation cohort. The Utah Score was significantly associated with BCVIs in the validation cohort (odds ratio 8.1 [3.3, 19.8], p < 0.001) and discriminated well in the validation cohort (area under the curve 72%). When the Utah Score was applied to the validation cohort, the sensitivity was 59%, specificity was 85%, positive predictive value was 18%, and negative predictive value was 97%. The Utah Score misclassified 16.6% of patients in the validation cohort. The Utah Score for predicting BCVI in pediatric trauma patients was validated with a low misclassification rate using a large, independent, multicenter cohort. Its implementation in the clinical setting may reduce the use of CTA in low-risk patients. PMID:27297774

Validation of the German Diabetes Risk Score within a population-based representative cohort.

PubMed

Hartwig, S; Kuss, O; Tiller, D; Greiser, K H; Schulze, M B; Dierkes, J; Werdan, K; Haerting, J; Kluttig, A

2013-09-01

To validate the German Diabetes Risk Score within the population-based cohort of the Cardiovascular Disease - Living and Ageing in Halle (CARLA) study. The sample included 582 women and 719 men, aged 45-83 years, who did not have diabetes at baseline. The individual risk of every participant was calculated using the German Diabetes Risk Score, which was modified for 4 years of follow-up. Predicted probabilities and observed outcomes were compared using Hosmer-Lemeshow goodness-of-fit tests and receiver-operator characteristic analyses. Changes in prediction power were investigated by expanding the German Diabetes Risk Score to include metabolic variables and by subgroup analyses. We found 58 cases of incident diabetes. The median 4-year probability of developing diabetes based on the German Diabetes Risk Score was 6.5%. The observed and predicted probabilities of developing diabetes were similar, although estimation was imprecise owing to the small number of cases, and the Hosmer-Lemeshow test returned a poor correlation (chi-squared = 55.3; P = 5.8*10⁻¹²). The area under the receiver-operator characteristic curve (AUC) was 0.70 (95% CI 0.64-0.77), and after excluding participants ≥66 years old, the AUC increased to 0.77 (95% CI 0.70-0.84). Consideration of glycaemic diagnostic variables, in addition to self-reported diabetes, reduced the AUC to 0.65 (95% CI 0.58-0.71). A new model that included the German Diabetes Risk Score and blood glucose concentration (AUC 0.81; 95% CI 0.76-0.86) or HbA(1c) concentration (AUC 0.84; 95% CI 0.80-0.91) was found to peform better. Application of the German Diabetes Risk Score in the CARLA cohort did not reproduce the findings in the European Prospective Investigation into Cancer and Nutrition (EPIC) Potsdam study, which may be explained by cohort differences and model overfit in the latter; however, a high score does provide an indication of increased risk of diabetes. © 2013 The Authors. Diabetic Medicine © 2013 Diabetes

External validation of the CAPRA-S score to predict biochemical recurrence, metastasis and mortality after radical prostatectomy in a European cohort.

PubMed

Tilki, Derya; Mandel, Philipp; Schlomm, Thorsten; Chun, Felix K-H; Tennstedt, Pierre; Pehrke, Dirk; Haese, Alexander; Huland, Hartwig; Graefen, Markus; Salomon, Georg

2015-06-01

The CAPRA-S score predicts prostate cancer recurrence based on pathological information from radical prostatectomy. To our knowledge CAPRA-S has never been externally validated in a European cohort. We independently validated CAPRA-S in a single institution European database. The study cohort comprised 14,532 patients treated with radical prostatectomy between January 1992 and August 2012. Prediction of biochemical recurrence, metastasis and cancer specific mortality by CAPRA-S was assessed by Kaplan-Meier analysis and the c-index. CAPRA-S performance to predict biochemical recurrence was evaluated by calibration plot and decision curve analysis. Median followup was 50.8 months (IQR 25.0-96.0). Biochemical recurrence developed in 20.3% of men at a median of 21.2 months (IQR 7.7-44.9). When stratifying patients by CAPRA-S risk group, estimated 5-year biochemical recurrence-free survival was 91.4%, 70.4% and 29.3% in the low, intermediate and high risk groups, respectively. The CAPRA-S c-index to predict biochemical recurrence, metastasis and cancer specific mortality was 0.80, 0.85 and 0.88, respectively. Metastasis developed in 417 men and 196 men died of prostate cancer. The CAPRA-S score was accurate when applied in a European study cohort. It predicted biochemical recurrence, metastasis and cancer specific mortality after radical prostatectomy with a c-index of greater than 0.80. The score can be valuable in regard to decision making for adjuvant therapy. Copyright © 2015. Published by Elsevier Inc.

Medical students' communication skills in clinical education: Results from a cohort study.

PubMed

Bachmann, Cadja; Roschlaub, Silke; Harendza, Sigrid; Keim, Rebecca; Scherer, Martin

2017-10-01

To assess students' communication skills during clinical medical education and at graduation. We conducted an observational cohort study from 2007 to 2011 with 26 voluntary undergraduate medical students at Hamburg University based on video-taped consultations in year four and at graduation. 176 consultations were analyzed quantitatively with validated and non-validated context-independent communication observation instruments (interrater reliability ≥0.8). Based on observational protocols each consultation was also documented in free-text comments, salient topics were extracted afterwards. 26 students, seven males, were enrolled in the survey. On average, graduates scored higher in differential-diagnostic questioning and time management but showed deficiencies in taking systematic and complete symptom-oriented histories, in communication techniques, in structuring consultations and in gathering the patients' perspectives. Patient-centeredness and empathy were rather low at graduation. Individual deficiencies could barely be eliminated. Medical students were able to enhance their clinical reasoning skills and their time management. Still, various communication deficiencies in final year students became evident regarding appropriate history taking, communication skills, empathy and patient-centeredness. The necessity of developing a longitudinal communication curriculum with enhanced communication trainings and assessments became evident. A curriculum should ensure that students' communication competencies are firmly achieved at graduation. Copyright © 2017. Published by Elsevier B.V.

Development and validation of the Surgical Outcome Risk Tool (SORT)

PubMed Central

Protopapa, K L; Simpson, J C; Smith, N C E; Moonesinghe, S R

2014-01-01

Background Existing risk stratification tools have limitations and clinical experience suggests they are not used routinely. The aim of this study was to develop and validate a preoperative risk stratification tool to predict 30-day mortality after non-cardiac surgery in adults by analysis of data from the observational National Confidential Enquiry into Patient Outcome and Death (NCEPOD) Knowing the Risk study. Methods The data set was split into derivation and validation cohorts. Logistic regression was used to construct a model in the derivation cohort to create the Surgical Outcome Risk Tool (SORT), which was tested in the validation cohort. Results Prospective data for 19 097 cases in 326 hospitals were obtained from the NCEPOD study. Following exclusion of 2309, details of 16 788 patients were analysed (derivation cohort 11 219, validation cohort 5569). A model of 45 risk factors was refined on repeated regression analyses to develop a model comprising six variables: American Society of Anesthesiologists Physical Status (ASA-PS) grade, urgency of surgery (expedited, urgent, immediate), high-risk surgical specialty (gastrointestinal, thoracic, vascular), surgical severity (from minor to complex major), cancer and age 65 years or over. In the validation cohort, the SORT was well calibrated and demonstrated better discrimination than the ASA-PS and Surgical Risk Scale; areas under the receiver operating characteristic (ROC) curve were 0·91 (95 per cent c.i. 0·88 to 0·94), 0·87 (0·84 to 0·91) and 0·88 (0·84 to 0·92) respectively (P < 0·001). Conclusion The SORT allows rapid and simple data entry of six preoperative variables, and provides a percentage mortality risk for individuals undergoing surgery. PMID:25388883

Decision curve analysis and external validation of the postoperative Karakiewicz nomogram for renal cell carcinoma based on a large single-center study cohort.

PubMed

Zastrow, Stefan; Brookman-May, Sabine; Cong, Thi Anh Phuong; Jurk, Stanislaw; von Bar, Immanuel; Novotny, Vladimir; Wirth, Manfred

2015-03-01

To predict outcome of patients with renal cell carcinoma (RCC) who undergo surgical therapy, risk models and nomograms are valuable tools. External validation on independent datasets is crucial for evaluating accuracy and generalizability of these models. The objective of the present study was to externally validate the postoperative nomogram developed by Karakiewicz et al. for prediction of cancer-specific survival. A total of 1,480 consecutive patients with a median follow-up of 82 months (IQR 46-128) were included into this analysis with 268 RCC-specific deaths. Nomogram-estimated survival probabilities were compared with survival probabilities of the actual cohort, and concordance indices were calculated. Calibration plots and decision curve analyses were used for evaluating calibration and clinical net benefit of the nomogram. Concordance between predictions of the nomogram and survival rates of the cohort was 0.911 after 12, 0.909 after 24 months and 0.896 after 60 months. Comparison of predicted probabilities and actual survival estimates with calibration plots showed an overestimation of tumor-specific survival based on nomogram predictions of high-risk patients, although calibration plots showed a reasonable calibration for probability ranges of interest. Decision curve analysis showed a positive net benefit of nomogram predictions for our patient cohort. The postoperative Karakiewicz nomogram provides a good concordance in this external cohort and is reasonably calibrated. It may overestimate tumor-specific survival in high-risk patients, which should be kept in mind when counseling patients. A positive net benefit of nomogram predictions was proven.

Evaluation of recruitment and selection for specialty training in public health: interim results of a prospective cohort study to measure the predictive validity of the selection process.

PubMed

Pashayan, Nora; Gray, Selena; Duff, Celia; Parkes, Julie; Williams, David; Patterson, Fiona; Koczwara, Anna; Fisher, Grant; Mason, Brendan W

2016-06-01

The recruitment process for public health specialty training includes an assessment centre (AC) with three components, Rust Advanced Numerical Reasoning Appraisal (RANRA), Watson-Glaser Critical Thinking Appraisal (WGCT) and a Situation Judgement Test (SJT), which determines invitation to a selection centre (SC). The scores are combined into a total recruitment (TR) score that determines the offers of appointment. A prospective cohort study using anonymous record linkage to investigate the association between applicant's scores in the recruitment process and registrar's progress through training measured by results of Membership Faculty Public Health (MFPH) examinations and outcomes of the Annual Review of Competence Progression (ARCP). Higher scores in RANRA, WGCT, AC, SC and TR were all significantly associated with higher adjusted odds of passing Part A MFPH exam at the first attempt. Higher scores in AC, SC and TR were significantly associated with passing Part B exam at the first attempt. Higher scores in SJT, AC and SC were significantly associated with satisfactory ARCP outcomes. The current UK national recruitment and selection process for public health specialty training has good predictive validity. The individual components of the process are testing different skills and abilities and together they are providing additive value. © The Author 2015. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The international primary ciliary dyskinesia cohort (iPCD Cohort): methods and first results.

PubMed

Goutaki, Myrofora; Maurer, Elisabeth; Halbeisen, Florian S; Amirav, Israel; Barbato, Angelo; Behan, Laura; Boon, Mieke; Casaulta, Carmen; Clement, Annick; Crowley, Suzanne; Haarman, Eric; Hogg, Claire; Karadag, Bulent; Koerner-Rettberg, Cordula; Leigh, Margaret W; Loebinger, Michael R; Mazurek, Henryk; Morgan, Lucy; Nielsen, Kim G; Omran, Heymut; Schwerk, Nicolaus; Scigliano, Sergio; Werner, Claudius; Yiallouros, Panayiotis; Zivkovic, Zorica; Lucas, Jane S; Kuehni, Claudia E

2017-01-01

Data on primary ciliary dyskinesia (PCD) epidemiology is scarce and published studies are characterised by low numbers. In the framework of the European Union project BESTCILIA we aimed to combine all available datasets in a retrospective international PCD cohort (iPCD Cohort).We identified eligible datasets by performing a systematic review of published studies containing clinical information on PCD, and by contacting members of past and current European Respiratory Society Task Forces on PCD. We compared the contents of the datasets, clarified definitions and pooled them in a standardised format.As of April 2016 the iPCD Cohort includes data on 3013 patients from 18 countries. It includes data on diagnostic evaluations, symptoms, lung function, growth and treatments. Longitudinal data are currently available for 542 patients. The extent of clinical details per patient varies between centres. More than 50% of patients have a definite PCD diagnosis based on recent guidelines. Children aged 10-19 years are the largest age group, followed by younger children (≤9 years) and young adults (20-29 years).This is the largest observational PCD dataset available to date. It will allow us to answer pertinent questions on clinical phenotype, disease severity, prognosis and effect of treatments, and to investigate genotype-phenotype correlations. Copyright ©ERS 2017.

The international primary ciliary dyskinesia cohort (iPCD Cohort): methods and first results

PubMed Central

Goutaki, Myrofora; Maurer, Elisabeth; Halbeisen, Florian S.; Amirav, Israel; Barbato, Angelo; Behan, Laura; Boon, Mieke; Casaulta, Carmen; Clement, Annick; Crowley, Suzanne; Haarman, Eric; Hogg, Claire; Karadag, Bulent; Koerner-Rettberg, Cordula; Leigh, Margaret W.; Loebinger, Michael R.; Mazurek, Henryk; Morgan, Lucy; Nielsen, Kim G.; Omran, Heymut; Schwerk, Nicolaus; Scigliano, Sergio; Werner, Claudius; Yiallouros, Panayiotis; Zivkovic, Zorica; Lucas, Jane S.

2017-01-01

Data on primary ciliary dyskinesia (PCD) epidemiology is scarce and published studies are characterised by low numbers. In the framework of the European Union project BESTCILIA we aimed to combine all available datasets in a retrospective international PCD cohort (iPCD Cohort). We identified eligible datasets by performing a systematic review of published studies containing clinical information on PCD, and by contacting members of past and current European Respiratory Society Task Forces on PCD. We compared the contents of the datasets, clarified definitions and pooled them in a standardised format. As of April 2016 the iPCD Cohort includes data on 3013 patients from 18 countries. It includes data on diagnostic evaluations, symptoms, lung function, growth and treatments. Longitudinal data are currently available for 542 patients. The extent of clinical details per patient varies between centres. More than 50% of patients have a definite PCD diagnosis based on recent guidelines. Children aged 10–19 years are the largest age group, followed by younger children (≤9 years) and young adults (20–29 years). This is the largest observational PCD dataset available to date. It will allow us to answer pertinent questions on clinical phenotype, disease severity, prognosis and effect of treatments, and to investigate genotype–phenotype correlations. PMID:28052956

Diagnosing gestational diabetes mellitus in the Danish National Birth Cohort.

PubMed

Olsen, Sjurdur F; Houshmand-Oeregaard, Azedeh; Granström, Charlotta; Langhoff-Roos, Jens; Damm, Peter; Bech, Bodil H; Vaag, Allan A; Zhang, Cuilin

2017-05-01

The Danish National Birth Cohort (DNBC) contains comprehensive information on diet, lifestyle, constitutional and other major characteristics of women during pregnancy. It provides a unique source for studies on health consequences of gestational diabetes mellitus. Our aim was to identify and validate the gestational diabetes mellitus cases in the cohort. We extracted clinical information from hospital records for 1609 pregnancies included in the Danish National Birth Cohort with a diagnosis of diabetes during or before pregnancy registered in the Danish National Patient Register and/or from a Danish National Birth Cohort interview during pregnancy. We further validated the diagnosis of gestational diabetes mellitus in 2126 randomly selected pregnancies from the entire Danish National Birth Cohort. From the individual hospital records, an expert panel evaluated gestational diabetes mellitus status based on results from oral glucose tolerance tests, fasting blood glucose and Hb1c values, as well as diagnoses made by local obstetricians. The audit categorized 783 pregnancies as gestational diabetes mellitus, corresponding to 0.89% of the 87 792 pregnancies for which a pregnancy interview for self-reported diabetes in pregnancy was available. From the randomly selected group the combined information from register and interviews could correctly identify 96% (95% CI 80-99.9%) of all cases in the entire Danish National Birth Cohort population. Positive predictive value, however, was only 59% (56-61%). The combined use of data from register and interview provided a high sensitivity for gestational diabetes mellitus diagnosis. The low positive predictive value, however, suggests that systematic validation by hospital record review is essential not to underestimate the health consequences of gestational diabetes mellitus in future studies. © 2016 Nordic Federation of Societies of Obstetrics and Gynecology.

Results from SMAP Validation Experiments 2015 and 2016

NASA Astrophysics Data System (ADS)

Colliander, A.; Jackson, T. J.; Cosh, M. H.; Misra, S.; Crow, W.; Powers, J.; Wood, E. F.; Mohanty, B.; Judge, J.; Drewry, D.; McNairn, H.; Bullock, P.; Berg, A. A.; Magagi, R.; O'Neill, P. E.; Yueh, S. H.

2017-12-01

NASA's Soil Moisture Active Passive (SMAP) mission was launched in January 2015. The objective of the mission is global mapping of soil moisture and freeze/thaw state. Well-characterized sites with calibrated in situ soil moisture measurements are used to determine the quality of the soil moisture data products; these sites are designated as core validation sites (CVS). To support the CVS-based validation, airborne field experiments are used to provide high-fidelity validation data and to improve the SMAP retrieval algorithms. The SMAP project and NASA coordinated airborne field experiments at three CVS locations in 2015 and 2016. SMAP Validation Experiment 2015 (SMAPVEX15) was conducted around the Walnut Gulch CVS in Arizona in August, 2015. SMAPVEX16 was conducted at the South Fork CVS in Iowa and Carman CVS in Manitoba, Canada from May to August 2016. The airborne PALS (Passive Active L-band Sensor) instrument mapped all experiment areas several times resulting in 30 coincidental measurements with SMAP. The experiments included intensive ground sampling regime consisting of manual sampling and augmentation of the CVS soil moisture measurements with temporary networks of soil moisture sensors. Analyses using the data from these experiments have produced various results regarding the SMAP validation and related science questions. The SMAPVEX15 data set has been used for calibration of a hyper-resolution model for soil moisture product validation; development of a multi-scale parameterization approach for surface roughness, and validation of disaggregation of SMAP soil moisture with optical thermal signal. The SMAPVEX16 data set has been already used for studying the spatial upscaling within a pixel with highly heterogeneous soil texture distribution; for understanding the process of radiative transfer at plot scale in relation to field scale and SMAP footprint scale over highly heterogeneous vegetation distribution; for testing a data fusion based soil moisture

Validation of the Singapore nomogram for outcome prediction in breast phyllodes tumours: an Australian cohort.

PubMed

Chng, Tze Wei; Lee, Jonathan Y H; Lee, C Soon; Li, HuiHua; Tan, Min-Han; Tan, Puay Hoon

2016-12-01

To validate the utility of the Singapore nomogram for outcome prediction in breast phyllodes tumours. Histological parameters, surgical margin status and clinical follow-up data of 34 women diagnosed with phyllodes tumours were analysed. Biostatistics modelling was performed, and the concordance between predicted and observed survivals was calculated. Women with a high nomogram score had an increased risk of developing relapse, which was predicted using the parameters defined by the Singapore nomogram. The Singapore nomogram is useful in predicting outcome in breast phyllodes tumours when applied to an Australian cohort of 34 women. 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/.

The performance of seven QPrediction risk scores in an independent external sample of patients from general practice: a validation study

PubMed Central

Hippisley-Cox, Julia; Coupland, Carol; Brindle, Peter

2014-01-01

Objectives To validate the performance of a set of risk prediction algorithms developed using the QResearch database, in an independent sample from general practices contributing to the Clinical Research Data Link (CPRD). Setting Prospective open cohort study using practices contributing to the CPRD database and practices contributing to the QResearch database. Participants The CPRD validation cohort consisted of 3.3 million patients, aged 25–99 years registered at 357 general practices between 1 Jan 1998 and 31 July 2012. The validation statistics for QResearch were obtained from the original published papers which used a one-third sample of practices separate to those used to derive the score. A cohort from QResearch was used to compare incidence rates and baseline characteristics and consisted of 6.8 million patients from 753 practices registered between 1 Jan 1998 and until 31 July 2013. Outcome measures Incident events relating to seven different risk prediction scores: QRISK2 (cardiovascular disease); QStroke (ischaemic stroke); QDiabetes (type 2 diabetes); QFracture (osteoporotic fracture and hip fracture); QKidney (moderate and severe kidney failure); QThrombosis (venous thromboembolism); QBleed (intracranial bleed and upper gastrointestinal haemorrhage). Measures of discrimination and calibration were calculated. Results Overall, the baseline characteristics of the CPRD and QResearch cohorts were similar though QResearch had higher recording levels for ethnicity and family history. The validation statistics for each of the risk prediction scores were very similar in the CPRD cohort compared with the published results from QResearch validation cohorts. For example, in women, the QDiabetes algorithm explained 50% of the variation within CPRD compared with 51% on QResearch and the receiver operator curve value was 0.85 on both databases. The scores were well calibrated in CPRD. Conclusions Each of the algorithms performed practically as well in the

Consequences of an Extended Recruitment on Participation in the Follow-Up of a Child Study: Results from the German IDEFICS Cohort.

PubMed

Langeheine, Malte; Pohlabeln, Hermann; Ahrens, Wolfgang; Rach, Stefan

2017-01-01

Declining response proportions in population-based studies are often countered by extended recruitment efforts at baseline that may, however, result in higher attrition in a subsequent follow-up. This study analysed the effect of extended recruitment efforts on attrition at the first follow-up of a child cohort. We used paradata (i.e. information about the process of data collection) from the German IDEFICS cohort investigating dietary- and life style-induced health effects on children to quantify recruitment effort and classify respondents as completing the recruitment early vs. late for baseline and follow-up separately. Multilevel logistic regression models were used to investigate the association between recruitment effort and attrition at follow-up (loss to follow-up) adjusted for sociodemographic and health related variables. Individuals who were late respondents at baseline and early respondents at the follow-up had a higher chance of attrition (odds ratio 1.65, 95% confidence interval (CI) 1.19, 2.28) as compared to other groups. An investigation of reasons for non-participation revealed that members of this group were more likely to be not reachable by phone. An extended recruitment effort at baseline of a child cohort study is not per se associated with a higher chance of attrition at follow-up. Much care should be taken to collect valid telephone numbers. © 2016 John Wiley & Sons Ltd.

Pulmonary artery enlargement and cystic fibrosis pulmonary exacerbations: a cohort study

PubMed Central

Wells, J. Michael; Farris, Roopan F.; Gosdin, Taylor A.; Dransfield, Mark T.; Wood, Michelle E.; Bell, Scott C.; Rowe, Steven M.

2017-01-01

Background Acute pulmonary exacerbations are associated with progressive lung function decline and increased mortality in cystic fibrosis (CF). The role of pulmonary vascular disease in pulmonary exacerbations is unknown. We investigated the association between pulmonary artery enlargement (PA:A>1), a marker of pulmonary vascular disease, and exacerbations. Methods We analyzed clinical, computed tomography (CT), and prospective exacerbation data in a derivation cohort of 74 adult CF patients, measuring the PA:A at the level of the PA bifurcation. We then replicated our findings in a validation cohort of 190 adult CF patients. Patients were separated into groups based on the presence or absence of a PA:A>1 and were followed for 1-year in the derivation cohort and 2-years in the validation cohort. The primary endpoint was developing ≥1 acute pulmonary exacerbation during follow-up. Linear and logistic regression models were used to determine associations between clinical factors, the PA:A ratio, and pulmonary exacerbations. We used Cox regression to determine time to first exacerbation in the validation cohort. Findings We found that PA:A>1 was present in n=37/74 (50%) of the derivation and n=89/190 (47%) of the validation cohort. In the derivation cohort, n=50/74 (68%) had ≥1 exacerbation at 1 year and n=133/190 (70%) in the validation cohort had ≥1 exacerbation after 2 years. PA:A>1 was associated with younger age in both cohorts and with elevated sweat chloride (100.5±10.9 versus 90.4±19.9mmol/L, difference between groups 10.1mmol/L [95%CI 2.5–17.7], P=0.017) in the derivation group. PA:A>1 was associated with exacerbations in the derivation (OR 3.49, 95%CI 1.18–10.3, P=0.023) and validation (OR 2.41, 95%CI 1.06–5.52, P=0.037) cohorts when adjusted for confounders. Time to first exacerbation was shorter in PA:A>1 versus PA:A<1 [HR 1.66 (95%CI 1.18–2.34), P=0.004] in unadjusted analysis, but not when adjusted for sex, BMI, prior exacerbation

Validity of Administrative Data in Identifying Cancer-related Events in Adolescents and Young Adults: A Population-based Study Using the IMPACT Cohort.

PubMed

Gupta, Sumit; Nathan, Paul C; Baxter, Nancy N; Lau, Cindy; Daly, Corinne; Pole, Jason D

2018-06-01

Despite the importance of estimating population level cancer outcomes, most registries do not collect critical events such as relapse. Attempts to use health administrative data to identify these events have focused on older adults and have been mostly unsuccessful. We developed and tested administrative data-based algorithms in a population-based cohort of adolescents and young adults with cancer. We identified all Ontario adolescents and young adults 15-21 years old diagnosed with leukemia, lymphoma, sarcoma, or testicular cancer between 1992-2012. Chart abstraction determined the end of initial treatment (EOIT) date and subsequent cancer-related events (progression, relapse, second cancer). Linkage to population-based administrative databases identified fee and procedure codes indicating cancer treatment or palliative care. Algorithms determining EOIT based on a time interval free of treatment-associated codes, and new cancer-related events based on billing codes, were compared with chart-abstracted data. The cohort comprised 1404 patients. Time periods free of treatment-associated codes did not validly identify EOIT dates; using subsequent codes to identify new cancer events was thus associated with low sensitivity (56.2%). However, using administrative data codes that occurred after the EOIT date based on chart abstraction, the first cancer-related event was identified with excellent validity (sensitivity, 87.0%; specificity, 93.3%; positive predictive value, 81.5%; negative predictive value, 95.5%). Although administrative data alone did not validly identify cancer-related events, administrative data in combination with chart collected EOIT dates was associated with excellent validity. The collection of EOIT dates by cancer registries would significantly expand the potential of administrative data linkage to assess cancer outcomes.

External validation and comparison of three prediction tools for risk of osteoporotic fractures using data from population based electronic health records: retrospective cohort study

PubMed Central

Cohen-Stavi, Chandra; Leventer-Roberts, Maya; Balicer, Ran D

2017-01-01

Objective To directly compare the performance and externally validate the three most studied prediction tools for osteoporotic fractures—QFracture, FRAX, and Garvan—using data from electronic health records. Design Retrospective cohort study. Setting Payer provider healthcare organisation in Israel. Participants 1 054 815 members aged 50 to 90 years for comparison between tools and cohorts of different age ranges, corresponding to those in each tools’ development study, for tool specific external validation. Main outcome measure First diagnosis of a major osteoporotic fracture (for QFracture and FRAX tools) and hip fractures (for all three tools) recorded in electronic health records from 2010 to 2014. Observed fracture rates were compared to probabilities predicted retrospectively as of 2010. Results The observed five year hip fracture rate was 2.7% and the rate for major osteoporotic fractures was 7.7%. The areas under the receiver operating curve (AUC) for hip fracture prediction were 82.7% for QFracture, 81.5% for FRAX, and 77.8% for Garvan. For major osteoporotic fractures, AUCs were 71.2% for QFracture and 71.4% for FRAX. All the tools underestimated the fracture risk, but the average observed to predicted ratios and the calibration slopes of FRAX were closest to 1. Tool specific validation analyses yielded hip fracture prediction AUCs of 88.0% for QFracture (among those aged 30-100 years), 81.5% for FRAX (50-90 years), and 71.2% for Garvan (60-95 years). Conclusions Both QFracture and FRAX had high discriminatory power for hip fracture prediction, with QFracture performing slightly better. This performance gap was more pronounced in previous studies, likely because of broader age inclusion criteria for QFracture validations. The simpler FRAX performed almost as well as QFracture for hip fracture prediction, and may have advantages if some of the input data required for QFracture are not available. However, both tools require calibration

Towards a model-based patient selection strategy for proton therapy: External validation of photon-derived Normal Tissue Complication Probability models in a head and neck proton therapy cohort

PubMed Central

Blanchard, P; Wong, AJ; Gunn, GB; Garden, AS; Mohamed, ASR; Rosenthal, DI; Crutison, J; Wu, R; Zhang, X; Zhu, XR; Mohan, R; Amin, MV; Fuller, CD; Frank, SJ

2017-01-01

Objective To externally validate head and neck cancer (HNC) photon-derived normal tissue complication probability (NTCP) models in patients treated with proton beam therapy (PBT). Methods This prospective cohort consisted of HNC patients treated with PBT at a single institution. NTCP models were selected based on the availability of data for validation and evaluated using the leave-one-out cross-validated area under the curve (AUC) for the receiver operating characteristics curve. Results 192 patients were included. The most prevalent tumor site was oropharynx (n=86, 45%), followed by sinonasal (n=28), nasopharyngeal (n=27) or parotid (n=27) tumors. Apart from the prediction of acute mucositis (reduction of AUC of 0.17), the models overall performed well. The validation (PBT) AUC and the published AUC were respectively 0.90 versus 0.88 for feeding tube 6 months post-PBT; 0.70 versus 0.80 for physician rated dysphagia 6 months post-PBT; 0.70 versus 0.80 for dry mouth 6 months post-PBT; and 0.73 versus 0.85 for hypothyroidism 12 months post-PBT. Conclusion While the drop in NTCP model performance was expected in PBT patients, the models showed robustness and remained valid. Further work is warranted, but these results support the validity of the model-based approach for treatment selection for HNC patients. PMID:27641784

42 CFR 476.84 - Changes as a result of DRG validation.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 4 2014-10-01 2014-10-01 false Changes as a result of DRG validation. 476.84... DRG validation. A provider or practitioner may obtain a review by a QIO under part 473 of this chapter... result of QIO validation activities. ...

Development and External Validation of the Korean Prostate Cancer Risk Calculator for High-Grade Prostate Cancer: Comparison with Two Western Risk Calculators in an Asian Cohort.

PubMed

Park, Jae Young; Yoon, Sungroh; Park, Man Sik; Choi, Hoon; Bae, Jae Hyun; Moon, Du Geon; Hong, Sung Kyu; Lee, Sang Eun; Park, Chanwang; Byun, Seok-Soo

2017-01-01

We developed the Korean Prostate Cancer Risk Calculator for High-Grade Prostate Cancer (KPCRC-HG) that predicts the probability of prostate cancer (PC) of Gleason score 7 or higher at the initial prostate biopsy in a Korean cohort (http://acl.snu.ac.kr/PCRC/RISC/). In addition, KPCRC-HG was validated and compared with internet-based Western risk calculators in a validation cohort. Using a logistic regression model, KPCRC-HG was developed based on the data from 602 previously unscreened Korean men who underwent initial prostate biopsies. Using 2,313 cases in a validation cohort, KPCRC-HG was compared with the European Randomized Study of Screening for PC Risk Calculator for high-grade cancer (ERSPCRC-HG) and the Prostate Cancer Prevention Trial Risk Calculator 2.0 for high-grade cancer (PCPTRC-HG). The predictive accuracy was assessed using the area under the receiver operating characteristic curve (AUC) and calibration plots. PC was detected in 172 (28.6%) men, 120 (19.9%) of whom had PC of Gleason score 7 or higher. Independent predictors included prostate-specific antigen levels, digital rectal examination findings, transrectal ultrasound findings, and prostate volume. The AUC of the KPCRC-HG (0.84) was higher than that of the PCPTRC-HG (0.79, p<0.001) but not different from that of the ERSPCRC-HG (0.83) on external validation. Calibration plots also revealed better performance of KPCRC-HG and ERSPCRC-HG than that of PCPTRC-HG on external validation. At a cut-off of 5% for KPCRC-HG, 253 of the 2,313 men (11%) would not have been biopsied, and 14 of the 614 PC cases with Gleason score 7 or higher (2%) would not have been diagnosed. KPCRC-HG is the first web-based high-grade prostate cancer prediction model in Korea. It had higher predictive accuracy than PCPTRC-HG in a Korean population and showed similar performance with ERSPCRC-HG in a Korean population. This prediction model could help avoid unnecessary biopsy and reduce overdiagnosis and overtreatment in

Early Prediction of Intensive Care Unit-Acquired Weakness: A Multicenter External Validation Study.

PubMed

Witteveen, Esther; Wieske, Luuk; Sommers, Juultje; Spijkstra, Jan-Jaap; de Waard, Monique C; Endeman, Henrik; Rijkenberg, Saskia; de Ruijter, Wouter; Sleeswijk, Mengalvio; Verhamme, Camiel; Schultz, Marcus J; van Schaik, Ivo N; Horn, Janneke

2018-01-01

An early diagnosis of intensive care unit-acquired weakness (ICU-AW) is often not possible due to impaired consciousness. To avoid a diagnostic delay, we previously developed a prediction model, based on single-center data from 212 patients (development cohort), to predict ICU-AW at 2 days after ICU admission. The objective of this study was to investigate the external validity of the original prediction model in a new, multicenter cohort and, if necessary, to update the model. Newly admitted ICU patients who were mechanically ventilated at 48 hours after ICU admission were included. Predictors were prospectively recorded, and the outcome ICU-AW was defined by an average Medical Research Council score <4. In the validation cohort, consisting of 349 patients, we analyzed performance of the original prediction model by assessment of calibration and discrimination. Additionally, we updated the model in this validation cohort. Finally, we evaluated a new prediction model based on all patients of the development and validation cohort. Of 349 analyzed patients in the validation cohort, 190 (54%) developed ICU-AW. Both model calibration and discrimination of the original model were poor in the validation cohort. The area under the receiver operating characteristics curve (AUC-ROC) was 0.60 (95% confidence interval [CI]: 0.54-0.66). Model updating methods improved calibration but not discrimination. The new prediction model, based on all patients of the development and validation cohort (total of 536 patients) had a fair discrimination, AUC-ROC: 0.70 (95% CI: 0.66-0.75). The previously developed prediction model for ICU-AW showed poor performance in a new independent multicenter validation cohort. Model updating methods improved calibration but not discrimination. The newly derived prediction model showed fair discrimination. This indicates that early prediction of ICU-AW is still challenging and needs further attention.

Development and validation of a risk-prediction nomogram for in-hospital mortality in adults poisoned with drugs and nonpharmaceutical agents

PubMed Central

Lionte, Catalina; Sorodoc, Victorita; Jaba, Elisabeta; Botezat, Alina

2017-01-01

Abstract Acute poisoning with drugs and nonpharmaceutical agents represents an important challenge in the emergency department (ED). The objective is to create and validate a risk-prediction nomogram for use in the ED to predict the risk of in-hospital mortality in adults from acute poisoning with drugs and nonpharmaceutical agents. This was a prospective cohort study involving adults with acute poisoning from drugs and nonpharmaceutical agents admitted to a tertiary referral center for toxicology between January and December 2015 (derivation cohort) and between January and June 2016 (validation cohort). We used a program to generate nomograms based on binary logistic regression predictive models. We included variables that had significant associations with death. Using regression coefficients, we calculated scores for each variable, and estimated the event probability. Model validation was performed using bootstrap to quantify our modeling strategy and using receiver operator characteristic (ROC) analysis. The nomogram was tested on a separate validation cohort using ROC analysis and goodness-of-fit tests. Data from 315 patients aged 18 to 91 years were analyzed (n = 180 in the derivation cohort; n = 135 in the validation cohort). In the final model, the following variables were significantly associated with mortality: age, laboratory test results (lactate, potassium, MB isoenzyme of creatine kinase), electrocardiogram parameters (QTc interval), and echocardiography findings (E wave velocity deceleration time). Sex was also included to use the same model for men and women. The resulting nomogram showed excellent survival/mortality discrimination (area under the curve [AUC] 0.976, 95% confidence interval [CI] 0.954–0.998, P < 0.0001 for the derivation cohort; AUC 0.957, 95% CI 0.892–1, P < 0.0001 for the validation cohort). This nomogram provides more precise, rapid, and simple risk-analysis information for individual patients acutely exposed to

Emergency Heart Failure Mortality Risk Grade score performance for 7-day mortality prediction in patients with heart failure attended at the emergency department: validation in a Spanish cohort.

PubMed

Gil, Víctor; Miró, Òscar; Schull, Michael J; Llorens, Pere; Herrero-Puente, Pablo; Jacob, Javier; Ríos, José; Lee, Douglas S; Martín-Sánchez, Francisco J

2018-06-01

The Emergency Heart Failure Mortality Risk Grade (EHMRG) scale, derived in 86 Canadian emergency departments (EDs), stratifies patients with acute-decompensated heart failure (ADHF) according to their 7-day mortality risk. We evaluated its external validity in a Spanish cohort. We applied the EHMRG scale to ADHF patients consecutively included in the Epidemiology of Acute Heart Failure in Emergency departments (EAHFE) registry (29 Spanish EDs) and measured its performance. Patients were distributed into quintiles according to the original and their self-defined score cutoffs. The 7-day mortality rates were compared internally among different categories and with categories of Canadian cohorts. The EAHFE group [n: 1553 patients; 80 (10) years; 55.6% women] had a 5.5% 7-day mortality rate and the EHMRG scale c-statistic was 0.741 (95% confidence interval: 0.688-0.793) compared with 0.807 (0.761-0.842) and 0.804 (0.763-0.840) obtained in the Canadian derivation and validation cohorts. The mortality rate of the EAHFE group mortality increased progressively as the quintile categories increased using intervals defined by either the Canadian or the Spanish EHMRG score cutoffs, although with more regular increments with the EAHFE-defined intervals; using the latter, patients at quintiles 2, 3, 4, 5a and 5b had (compared with quintile 1) odds ratios of 1.77, 3.36, 4.44, 9.39 and 16.19, respectively. The EHMRG scale stratified risk in an ADHF cohort that included both palliative and nonpalliative patients in Spanish EDs, showing an extrapolation to a higher mortality risk cohort than the original derivation sample. Stratification improved when the score was recalibrated in the Spanish cohort.

Validation of the Children's Eating Behavior Questionnaire in 3 year old children of a multi-ethnic Asian population: The GUSTO cohort study.

PubMed

Quah, Phaik Ling; Cheung, Yin Bun; Pang, Wei Wei; Toh, Jia Ying; Saw, Seang-Mei; Godfrey, Keith M; Yap, Fabian; Chong, Yap Seng; Mary, Chong Foong-Fong

2017-06-01

The Children's Eating Behaviour Questionnaire (CEBQ) was developed to measure eating behaviors related to obesity risk in children. However, this questionnaire has not been validated for use in South East Asia, where parenting practices are different from those in western countries and child obesity rates are increasing. The aim of this study was to examine the validity of the CEBQ administered to mothers of children aged 3 years in Singapore. Confirmatory factor analysis (CFA) was used to examine if the original 35-item, 8-factor model was supported in our cohort. Participants were 636 mother-child dyads (mean (SD) child age = 36.7 (1.6) months), from the Growing Up in Singapore Towards healthy Outcomes (GUSTO) birth cohort in which the mothers were characterized in pregnancy and children were followed up to age 3 years. The CFA showed a poor model fit; RMSEA = 0.072 (PCLOSE<0.001), SRMR = 0.094, CFI = 0.826, and TLI = 0.805. Exploratory factor analysis revealed a 35 item, 7-factor structure (factor loadings ≥ 0.35): enjoyment of food, food fussiness, emotional overeating, desire to drink, emotional under eating, satiety responsiveness and slowness in eating. Cronbach's alpha estimates ranged from 0.70 to 0.88 for the 7 subscales. Convergent validity tests via correlation analysis revealed that emotional under eating (r = -0.14), slowness in eating (r = -0.16) and satiety responsiveness (r = -0.11) were negatively correlated with BMI z-score at 3 years, while enjoyment of food (r = 0.12) was positively correlated, p < 0.05. In conclusion, we found a revised 7-factor structure of the CEBQ more appropriate for examining eating behavior in 3 year old children in the Singapore setting. Further replication studies in a separate cohort study are warranted before further use of these factor structures generated. Copyright © 2017 Elsevier Ltd. All rights reserved.

Validity of empirical models of exposure in asphalt paving

PubMed Central

Burstyn, I; Boffetta, P; Burr, G; Cenni, A; Knecht, U; Sciarra, G; Kromhout, H

2002-01-01

Aims: To investigate the validity of empirical models of exposure to bitumen fume and benzo(a)pyrene, developed for a historical cohort study of asphalt paving in Western Europe. Methods: Validity was evaluated using data from the USA, Italy, and Germany not used to develop the original models. Correlation between observed and predicted exposures was examined. Bias and precision were estimated. Results: Models were imprecise. Furthermore, predicted bitumen fume exposures tended to be lower (-70%) than concentrations found during paving in the USA. This apparent bias might be attributed to differences between Western European and USA paving practices. Evaluation of the validity of the benzo(a)pyrene exposure model revealed a similar to expected effect of re-paving and a larger than expected effect of tar use. Overall, benzo(a)pyrene models underestimated exposures by 51%. Conclusions: Possible bias as a result of underestimation of the impact of coal tar on benzo(a)pyrene exposure levels must be explored in sensitivity analysis of the exposure–response relation. Validation of the models, albeit limited, increased our confidence in their applicability to exposure assessment in the historical cohort study of cancer risk among asphalt workers. PMID:12205236

Validity of physical activity and cardiorespiratory fitness in the Danish cohort "Diet, Cancer and Health-Next Generations".

PubMed

Lerche, L; Olsen, A; Petersen, K E N; Rostgaard-Hansen, A L; Dragsted, L O; Nordsborg, N B; Tjønneland, A; Halkjaer, J

2017-12-01

Valid assessments of physical activity (PA) and cardiorespiratory fitness (CRF) are essential in epidemiological studies to define dose-response relationship for formulating thorough recommendations of an appropriate pattern of PA to maintain good health. The aim of this study was to validate the Danish step test, the physical activity questionnaire Active-Q, and self-rated fitness against directly measured maximal oxygen uptake (VO 2 max). A population-based subsample (n=125) was included from the "Diet, Cancer and Health-Next Generations" (DCH-NG) cohort which is under establishment. Validity coefficients, which express the correlation between measured and "true" exposure, were calculated, and misclassification across categories was evaluated. The validity of the Danish step test was moderate (women: r=.66, and men: r=.56); however, men were systematically underestimated (43% misclassification). When validating the questionnaire-derived measures of PA, leisure-time physical activity was not correlated with VO 2 max. Positive correlations were found for sports overall, but these were only significant for men: total hours per week of sports (r=.26), MET-hours per week of sports (r=.28) and vigorous sports (0.28) alone were positively correlated with VO 2 max. Finally, the percentage of misclassification was low for self-rated fitness (women: 9% and men: 13%). Thus, self-rated fitness was found to be a superior method to the Danish step test, as well as being less cost prohibitive and more practical than the VO 2 max method. Finally, even if correlations were low, they support the potential for questionnaire outcomes, particularly sports, vigorous sports, and self-rated fitness to be used to estimate CRF. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Complete Versus Staged Repair for Neonates With Tetralogy of Fallot: Establishment and Validation of a Cohort of 2235 Patients Using Detailed Surgery Sequence Review of Health Care Administrative Data.

PubMed

Savla, Jill J; Fisher, Brian T; Faerber, Jennifer A; Huang, Yuan-Shung V; Mercer-Rosa, Laura

2017-12-12

The surgical strategy for neonates with tetralogy of Fallot (TOF) consists of complete or staged repair. Assessing the comparative effectiveness of these approaches is facilitated by a large multicenter cohort. We propose a novel process for cohort assembly using the Pediatric Health Information System (PHIS), an administrative database that contains clinical and billing data for inpatient and emergency department stays from tertiary children's hospitals. A 4-step process was used to identify neonates with TOF: (1) screen neonates in PHIS with International Classification of Diseases-9 (ICD-9) diagnosis or procedure codes for TOF; (2) include patients with TOF procedures before 30 days of age; (3) exclude patients with missing 2-year follow-up data; (4) analyze patients' 2-year surgery sequence patterns, exclude patients inconsistent with a treatment strategy for TOF, and designate patients as complete or staged repair. Manual chart review at 1 PHIS center was performed to validate this process. Between January 2004 and March 2015, 5862 patients were identified in step 1. Step 2 of cohort assembly excluded 3425 patients (58%); step 3 excluded 148 patients (3%); and step 4 excluded 54 patients (1%). The final cohort consisted of 2235 neonates with TOF from 45 hospitals. Manual chart review of 336 patients showed a positive predictive value for accurate PHIS identification of 44% after step 1 and 97% after step 4. This systematic cohort identification algorithm resulted in a high positive predictive value to appropriately categorize patients. This carefully assembled cohort offers a unique opportunity for future studies in neonatal TOF outcomes.

Stroke after Aortic Valve Surgery: Results from a Prospective Cohort

PubMed Central

Messé, Steven R.; Acker, Michael A.; Kasner, Scott E.; Fanning, Molly; Giovannetti, Tania; Ratcliffe, Sarah J.; Bilello, Michel; Szeto, Wilson Y.; Bavaria, Joseph E.; Hargrove, W. Clark; Mohler, Emile R.; Floyd, Thomas F.

2014-01-01

Background The incidence and impact of clinical stroke and silent radiographic cerebral infarction complicating open surgical aortic valve replacement (AVR) are poorly characterized. Methods and Results We performed a prospective cohort study of subjects ≥ 65 years of age undergoing AVR for calcific aortic stenosis. Subjects were evaluated by neurologists pre-operatively and post-operatively, and underwent post-operative magnetic resonance imaging (MRI). Over a 4 year period, 196 subjects were enrolled at 2 sites. Mean age = 75.8 ± 6.2 years, 36% female, 6% non-white. Clinical strokes were detected in 17%, Transient Ischemic Attack in 2%, and in-hospital mortality was 5%. The frequency of stroke in the Society for Thoracic Surgery (STS) database in this cohort was 7%. Most strokes were mild; the median National Institutes of Health Stroke Scale (NIHSS) was 3 (interquartile range 1 – 9). Clinical stroke was associated with increased length of stay, median 12 vs 10 days, p = 0.02. Moderate or severe stroke (NIHSS ≥10) occurred in 8 (4%) and was strongly associated with in-hospital mortality, 38% vs 4%, p = 0.005. Of the 109 stroke-free subjects with post-operative MRI, silent infarct was identified in 59 (54%). Silent infarct was not associated with in-hospital mortality or increased length of stay. Conclusions Clinical stroke after AVR was more common than previously reported, more than double for this same cohort in the STS database, and silent cerebral infarctions were detected in over half of patients undergoing AVR. Clinical stroke complicating AVR is associated with increased length of stay and mortality. PMID:24690611

External validation of the diffuse intrinsic pontine glioma survival prediction model: a collaborative report from the International DIPG Registry and the SIOPE DIPG Registry.

PubMed

Veldhuijzen van Zanten, Sophie E M; Lane, Adam; Heymans, Martijn W; Baugh, Joshua; Chaney, Brooklyn; Hoffman, Lindsey M; Doughman, Renee; Jansen, Marc H A; Sanchez, Esther; Vandertop, William P; Kaspers, Gertjan J L; van Vuurden, Dannis G; Fouladi, Maryam; Jones, Blaise V; Leach, James

2017-08-01

We aimed to perform external validation of the recently developed survival prediction model for diffuse intrinsic pontine glioma (DIPG), and discuss its utility. The DIPG survival prediction model was developed in a cohort of patients from the Netherlands, United Kingdom and Germany, registered in the SIOPE DIPG Registry, and includes age <3 years, longer symptom duration and receipt of chemotherapy as favorable predictors, and presence of ring-enhancement on MRI as unfavorable predictor. Model performance was evaluated by analyzing the discrimination and calibration abilities. External validation was performed using an unselected cohort from the International DIPG Registry, including patients from United States, Canada, Australia and New Zealand. Basic comparison with the results of the original study was performed using descriptive statistics, and univariate- and multivariable regression analyses in the validation cohort. External validation was assessed following a variety of analyses described previously. Baseline patient characteristics and results from the regression analyses were largely comparable. Kaplan-Meier curves of the validation cohort reproduced separated groups of standard (n = 39), intermediate (n = 125), and high-risk (n = 78) patients. This discriminative ability was confirmed by similar values for the hazard ratios across these risk groups. The calibration curve in the validation cohort showed a symmetric underestimation of the predicted survival probabilities. In this external validation study, we demonstrate that the DIPG survival prediction model has acceptable cross-cohort calibration and is able to discriminate patients with short, average, and increased survival. We discuss how this clinico-radiological model may serve a useful role in current clinical practice.

Cognitive Enhancement in Infants Associated with Increased Maternal Fruit Intake During Pregnancy: Results from a Birth Cohort Study with Validation in an Animal Model.

PubMed

Bolduc, Francois V; Lau, Amanda; Rosenfelt, Cory S; Langer, Steven; Wang, Nan; Smithson, Lisa; Lefebvre, Diana; Alexander, R Todd; Dickson, Clayton T; Li, Liang; Becker, Allan B; Subbarao, Padmaja; Turvey, Stuart E; Pei, Jacqueline; Sears, Malcolm R; Mandhane, Piush J

2016-06-01

In-utero nutrition is an under-studied aspect of cognitive development. Fruit has been an important dietary constituent for early hominins and humans. Among 808 eligible CHILD-Edmonton sub-cohort subjects, 688 (85%) had 1-year cognitive outcome data. We found that each maternal daily serving of fruit (sum of fruit plus 100% fruit juice) consumed during pregnancy was associated with a 2.38 point increase in 1-year cognitive development (95% CI 0.39, 4.37; p<0.05). Consistent with this, we found 30% higher learning Performance index (PI) scores in Drosophila offspring from parents who consumed 30% fruit juice supplementation prenatally (PI: 85.7; SE 1.8; p<0.05) compared to the offspring of standard diet parents (PI: 65.0 SE 3.4). Using the Drosophila model, we also show that the cyclic adenylate monophosphate (cAMP) pathway may be a major regulator of this effect, as prenatal fruit associated cognitive enhancement was blocked in Drosophila rutabaga mutants with reduced Ca(2+)-Calmodulin-dependent adenylyl cyclase. Moreover, gestation is a critical time for this effect as postnatal fruit intake did not enhance cognitive performance in either humans or Drosophila. Our study supports increased fruit consumption during pregnancy with significant increases in infant cognitive performance. Validation in Drosophila helps control for potential participant bias or unmeasured confounders. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Validation of Computerized Automatic Calculation of the Sequential Organ Failure Assessment Score

PubMed Central

Harrison, Andrew M.; Pickering, Brian W.; Herasevich, Vitaly

2013-01-01

Purpose. To validate the use of a computer program for the automatic calculation of the sequential organ failure assessment (SOFA) score, as compared to the gold standard of manual chart review. Materials and Methods. Adult admissions (age > 18 years) to the medical ICU with a length of stay greater than 24 hours were studied in the setting of an academic tertiary referral center. A retrospective cross-sectional analysis was performed using a derivation cohort to compare automatic calculation of the SOFA score to the gold standard of manual chart review. After critical appraisal of sources of disagreement, another analysis was performed using an independent validation cohort. Then, a prospective observational analysis was performed using an implementation of this computer program in AWARE Dashboard, which is an existing real-time patient EMR system for use in the ICU. Results. Good agreement between the manual and automatic SOFA calculations was observed for both the derivation (N=94) and validation (N=268) cohorts: 0.02 ± 2.33 and 0.29 ± 1.75 points, respectively. These results were validated in AWARE (N=60). Conclusion. This EMR-based automatic tool accurately calculates SOFA scores and can facilitate ICU decisions without the need for manual data collection. This tool can also be employed in a real-time electronic environment. PMID:23936639

Lean body mass: the development and validation of prediction equations in healthy adults

PubMed Central

2013-01-01

Background There is a loss of lean body mass (LBM) with increasing age. A low LBM has been associated with increased adverse effects from prescribed medications such as chemotherapy. Accurate assessment of LBM may allow for more accurate drug prescribing. The aims of this study were to develop new prediction equations (PEs) for LBM with anthropometric and biochemical variables from a development cohort and then validate the best performing PEs in validation cohorts. Methods PEs were developed in a cohort of 188 healthy subjects and then validated in a convenience cohort of 52 healthy subjects. The best performing anthropometric PE was then compared to published anthropometric PEs in an older (age ≥ 50 years) cohort of 2287 people. Best subset regression analysis was used to derive PEs. Correlation, Bland-Altman and Sheiner & Beal methods were used to validate and compare the PEs against dual X-ray absorptiometry (DXA)-derived LBM. Results The PE which included biochemistry variables performed only marginally better than the anthropometric PE. The anthropometric PE on average over-estimated LBM by 0.74 kg in the combined cohort. Across gender (male vs. female), body mass index (< 22, 22- < 27, 27- < 30 and ≥30 kg/m2) and age groups (50–64, 65–79 and ≥80 years), the maximum mean over-estimation of the anthropometric PE was 1.36 kg. Conclusions A new anthropometric PE has been developed that offers an alternative for clinicians when access to DXA is limited. Further research is required to determine the clinical utility and if it will improve the safety of medication use. PMID:24499708

Brief Report: Predicting Functional Disability: One-Year Results From the Scottish Early Rheumatoid Arthritis Inception Cohort.

PubMed

Kronisch, Caroline; McLernon, David J; Dale, James; Paterson, Caron; Ralston, Stuart H; Reid, David M; Tierney, Ann; Harvie, John; McKay, Neil; Wilson, Hilary E; Munro, Robin; Saunders, Sarah; Richmond, Ruth; Baxter, Derek; McMahon, Mike; Kumar, Vinod; McLaren, John; Siebert, Stefan; McInnes, Iain B; Porter, Duncan; Macfarlane, Gary J; Basu, Neil

2016-07-01

To identify baseline prognostic indicators of disability at 1 year within a contemporary early inflammatory arthritis inception cohort and then develop a clinically useful tool to support early patient education and decision-making. The Scottish Early Rheumatoid Arthritis (SERA) inception cohort is a multicenter, prospective study of patients with newly presenting RA or undifferentiated arthritis. SERA data were analyzed to determine baseline predictors of disability (defined as a Health Assessment Questionnaire [HAQ] score of ≥1) at 1 year. Clinical and psychosocial baseline exposures were entered into a forward stepwise logistic regression model. The model was externally validated using newly accrued SERA data and subsequently converted into a prediction tool. Of the 578 participants (64.5% female), 36.7% (n = 212) reported functional disability at 1 year. Functional disability was independently predicted by baseline disability (odds ratio [OR] 2.67 [95% confidence interval (95% CI) 1.98, 3.59]), depression (OR 2.52 [95% CI 1.18, 5.37]), anxiety (OR 2.37 [95% CI 1.33, 4.21]), being in paid employment with absenteeism during the last week (OR 1.19 [95% CI 0.63, 2.23]), not being in paid employment (OR 2.36 [95% CI 1.38, 4.03]), and being overweight (OR 1.61 [95% CI 1.04, 2.50]). External validation (using 113 newly acquired patients) evidenced good discriminative performance with a C statistic of 0.74, and the calibration slope showed no evidence of model overfit (P = 0.31). In the context of modern early inflammatory arthritis treatment paradigms, predictors of disability at 1 year appear to be dominated by psychosocial rather than more traditional clinical measures. This indicates the potential benefit of early access to nonpharmacologic interventions targeting key psychosocial factors, such as mental health and work disability. © 2016, American College of Rheumatology.

Validation of the Social Appearance Anxiety Scale in Patients with Systemic Sclerosis: A Scleroderma Patient-centered Intervention Network Cohort Study.

PubMed

Mills, Sarah D; Kwakkenbos, Linda; Carrier, Marie-Eve; Gholizadeh, Shadi; Fox, Rina S; Jewett, Lisa R; Gottesman, Karen; Roesch, Scott C; Thombs, Brett D; Malcarne, Vanessa L

2018-01-17

Systemic sclerosis (SSc) is an autoimmune disease that can cause disfiguring changes in appearance. This study examined the structural validity, internal consistency reliability, convergent validity, and measurement equivalence of the Social Appearance Anxiety Scale (SAAS) across SSc disease subtypes. Patients enrolled in the Scleroderma Patient-centered Intervention Network Cohort completed the SAAS and measures of appearance-related concerns and psychological distress. Confirmatory factor analysis (CFA) was used to examine the structural validity of the SAAS. Multiple-group CFA was used to determine if SAAS scores can be compared across patients with limited and diffuse disease subtypes. Cronbach's alpha was used to examine internal consistency reliability. Correlations of SAAS scores with measures of body image dissatisfaction, fear of negative evaluation, social anxiety, and depression were used to examine convergent validity. SAAS scores were hypothesized to be positively associated with all convergent validity measures, with correlations significant and moderate to large in size. A total of 938 patients with SSc were included. CFA supported a one-factor structure (CFI: .92; SRMR: .04; RMSEA: .08), and multiple-group CFA indicated that the scalar invariance model best fit the data. Internal consistency reliability was good in the total sample (α = .96) and in disease subgroups. Overall, evidence of convergent validity was found with measures of body image dissatisfaction, fear of negative evaluation, social anxiety, and depression. The SAAS can be reliably and validly used to assess fear of appearance evaluation in patients with SSc, and SAAS scores can be meaningfully compared across disease subtypes. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

10 CFR 26.139 - Reporting initial validity and drug test results.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false Reporting initial validity and drug test results. 26.139... § 26.139 Reporting initial validity and drug test results. (a) The licensee testing facility shall... permitted under § 26.75(h), positive test results from initial drug tests at the licensee testing facility...

10 CFR 26.139 - Reporting initial validity and drug test results.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Reporting initial validity and drug test results. 26.139... § 26.139 Reporting initial validity and drug test results. (a) The licensee testing facility shall... permitted under § 26.75(h), positive test results from initial drug tests at the licensee testing facility...

Validation of the German version of the Nurse-Work Instability Scale: baseline survey findings of a prospective study of a cohort of geriatric care workers

PubMed Central

2013-01-01

Background A prospective study of a cohort of nursing staff from nursing homes was undertaken to validate the Nurse-Work Instability Scale (Nurse-WIS). Baseline investigation data was used to test reliability, construct validity and criterion validity. Method A survey of nursing staff from nursing homes was conducted using a questionnaire containing the Nurse-WIS along with other survey instruments (including SF-12, WAI, SPE). The self-reported number of days’ sick leave taken and if a pension for reduced work capacity was drawn were recorded. The reliability of the scale was checked by item difficulty (P), item discrimination (rjt) and by internal consistency according to Cronbach’s coefficient. The hypotheses for checking construct validity were tested on the basis of correlations. Pearson’s chi-square was used to test concurrent criterion validity; discriminant validity was tested by means of binary logistic regression. Results 396 persons answered the questionnaire (21.3% response rate). More than 80% were female and mostly work full-time in a rotating shift pattern. Following the test for item discrimination, two items were removed from the Nurse-WIS test. According to Cronbach’s (0.927) the scale provides a high degree of measuring accuracy. All hypotheses and assumptions used to test validity were confirmed: As the Nurse-WIS risk increases, health-related quality of life, work ability and job satisfaction decline. Depressive symptoms and a poor subjective prognosis of earning capacity are also more frequent. Musculoskeletal disorders and impairments of psychological well-being are more frequent. Age also influences the Nurse-WIS result. While 12.0% of those below the age of 35 had an increased risk, the figure for those aged over 55 was 50%. Conclusion This study is the first validation study of the Nurse-WIS to date. The Nurse-WIS shows good reliability, good validity and a good level of measuring accuracy. It appears to be suitable for recording

Improving the Validity of Activity of Daily Living Dependency Risk Assessment

PubMed Central

Clark, Daniel O.; Stump, Timothy E.; Tu, Wanzhu; Miller, Douglas K.

2015-01-01

Objectives Efforts to prevent activity of daily living (ADL) dependency may be improved through models that assess older adults’ dependency risk. We evaluated whether cognition and gait speed measures improve the predictive validity of interview-based models. Method Participants were 8,095 self-respondents in the 2006 Health and Retirement Survey who were aged 65 years or over and independent in five ADLs. Incident ADL dependency was determined from the 2008 interview. Models were developed using random 2/3rd cohorts and validated in the remaining 1/3rd. Results Compared to a c-statistic of 0.79 in the best interview model, the model including cognitive measures had c-statistics of 0.82 and 0.80 while the best fitting gait speed model had c-statistics of 0.83 and 0.79 in the development and validation cohorts, respectively. Conclusion Two relatively brief models, one that requires an in-person assessment and one that does not, had excellent validity for predicting incident ADL dependency but did not significantly improve the predictive validity of the best fitting interview-based models. PMID:24652867

Nut consumption and total and cause-specific mortality: results from the Golestan Cohort Study

PubMed Central

Eslamparast, Tannaz; Sharafkhah, Maryam; Poustchi, Hossein; Hashemian, Maryam; Dawsey, Sanford M; Freedman, Neal D; Boffetta, Paolo; Abnet, Christian C; Etemadi, Arash; Pourshams, Akram; Malekshah, Akbar Fazeltabar; Islami, Farhad; Kamangar, Farin; Merat, Shahin; Brennan, Paul; Hekmatdoost, Azita; Malekzadeh, Reza

2017-01-01

Abstract Background: A number of prospective studies have observed inverse associations between nut consumption and chronic diseases. However, these studies have predominantly been conducted in Western countries, where nut consumption tends to be more common among individuals with healthier lifestyles. It is important to examine the association in other parts of the world, and particularly among populations with different patterns of disease, socioeconomic status, lifestyles and disease risk factors. Our objective was to examine the association between nut consumption and mortality in a population whose nut consumption does not track with a healthy lifestyle. Methods: We examined the association between nut consumption and all-cause and cause-specific mortality in the 50 045 participants of the Golestan Cohort Study. Participants were aged 40 and older at baseline in 2004, and have been actively followed since that time. Dietary data were collected using a validated semi-quantitative food frequency questionnaire that was administered at baseline. Results: During 349 677 person-years of follow-up, 3981 cohort participants died, including 1732 women and 2249 men. Nut consumption was associated inversely with all-cause mortality. The pooled multivariate adjusted hazard ratios for death among participants who ate nuts, as compared with those who did not, were 0.89 [95% confidence interval (CI), 0.82-0.95] for the consumption of less than one serving of nuts per week, 0.75 (95% CI, 0.67-0.85) for one to less than three servings per week and 0.71 (95% CI, 0.58-0.86) for three or more servings per week (P < 0.001 for trend). Among specific causes, significant inverse associations were observed between nut consumption and deaths due to cardiovascular disease, all cancers and gastrointestinal cancers. Conclusions: This study provides evidence for an inverse association between nut consumption and mortality in a developing country, where nut consumption does not track with a

42 CFR 476.84 - Changes as a result of DRG validation.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 4 2010-10-01 2010-10-01 false Changes as a result of DRG validation. 476.84... § 476.84 Changes as a result of DRG validation. A provider or practitioner may obtain a review by a QIO under part 473 of this chapter for changes in diagnostic and procedural coding that resulted in a change...

42 CFR 476.84 - Changes as a result of DRG validation.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 4 2012-10-01 2012-10-01 false Changes as a result of DRG validation. 476.84... § 476.84 Changes as a result of DRG validation. A provider or practitioner may obtain a review by a QIO under part 473 of this chapter for changes in diagnostic and procedural coding that resulted in a change...

42 CFR 476.84 - Changes as a result of DRG validation.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 4 2013-10-01 2013-10-01 false Changes as a result of DRG validation. 476.84... § 476.84 Changes as a result of DRG validation. A provider or practitioner may obtain a review by a QIO under part 473 of this chapter for changes in diagnostic and procedural coding that resulted in a change...

42 CFR 476.84 - Changes as a result of DRG validation.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 4 2011-10-01 2011-10-01 false Changes as a result of DRG validation. 476.84... § 476.84 Changes as a result of DRG validation. A provider or practitioner may obtain a review by a QIO under part 473 of this chapter for changes in diagnostic and procedural coding that resulted in a change...

42 CFR 478.15 - QIO review of changes resulting from DRG validation.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 4 2014-10-01 2014-10-01 false QIO review of changes resulting from DRG validation... review of changes resulting from DRG validation. (a) General rules. (1) A provider or practitioner... validation under section 1866(a)(1)(F) of the Act is entitled to a review of that change if— (i) The change...

42 CFR 478.15 - QIO review of changes resulting from DRG validation.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 4 2013-10-01 2013-10-01 false QIO review of changes resulting from DRG validation... review of changes resulting from DRG validation. (a) General rules. (1) A provider or practitioner... validation under section 1866(a)(1)(F) of the Act is entitled to a review of that change if— (i) The change...

42 CFR 478.15 - QIO review of changes resulting from DRG validation.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 4 2011-10-01 2011-10-01 false QIO review of changes resulting from DRG validation... review of changes resulting from DRG validation. (a) General rules. (1) A provider or practitioner... validation under section 1866(a)(1)(F) of the Act is entitled to a review of that change if— (i) The change...

42 CFR 478.15 - QIO review of changes resulting from DRG validation.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 4 2012-10-01 2012-10-01 false QIO review of changes resulting from DRG validation... review of changes resulting from DRG validation. (a) General rules. (1) A provider or practitioner... validation under section 1866(a)(1)(F) of the Act is entitled to a review of that change if— (i) The change...

42 CFR 493.571 - Disclosure of accreditation, State and CMS validation inspection results.

Code of Federal Regulations, 2013 CFR

2013-10-01

... validation inspection results. 493.571 Section 493.571 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES... Program § 493.571 Disclosure of accreditation, State and CMS validation inspection results. (a... licensure program, in accordance with State law. (c) CMS validation inspection results. CMS may disclose the...

42 CFR 493.571 - Disclosure of accreditation, State and CMS validation inspection results.

Code of Federal Regulations, 2011 CFR

2011-10-01

... validation inspection results. 493.571 Section 493.571 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES... Program § 493.571 Disclosure of accreditation, State and CMS validation inspection results. (a... licensure program, in accordance with State law. (c) CMS validation inspection results. CMS may disclose the...

42 CFR 493.571 - Disclosure of accreditation, State and CMS validation inspection results.

Code of Federal Regulations, 2012 CFR

2012-10-01

... validation inspection results. 493.571 Section 493.571 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES... Program § 493.571 Disclosure of accreditation, State and CMS validation inspection results. (a... licensure program, in accordance with State law. (c) CMS validation inspection results. CMS may disclose the...

42 CFR 493.571 - Disclosure of accreditation, State and CMS validation inspection results.

Code of Federal Regulations, 2010 CFR

2010-10-01

... validation inspection results. 493.571 Section 493.571 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES... Program § 493.571 Disclosure of accreditation, State and CMS validation inspection results. (a... licensure program, in accordance with State law. (c) CMS validation inspection results. CMS may disclose the...

42 CFR 493.571 - Disclosure of accreditation, State and CMS validation inspection results.

Code of Federal Regulations, 2014 CFR

2014-10-01

... validation inspection results. 493.571 Section 493.571 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES... Program § 493.571 Disclosure of accreditation, State and CMS validation inspection results. (a... licensure program, in accordance with State law. (c) CMS validation inspection results. CMS may disclose the...

10 CFR 26.139 - Reporting initial validity and drug test results.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Reporting initial validity and drug test results. 26.139 Section 26.139 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Licensee Testing Facilities § 26.139 Reporting initial validity and drug test results. (a) The licensee testing facility shall...

10 CFR 26.139 - Reporting initial validity and drug test results.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Reporting initial validity and drug test results. 26.139 Section 26.139 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Licensee Testing Facilities § 26.139 Reporting initial validity and drug test results. (a) The licensee testing facility shall...

10 CFR 26.139 - Reporting initial validity and drug test results.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false Reporting initial validity and drug test results. 26.139 Section 26.139 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Licensee Testing Facilities § 26.139 Reporting initial validity and drug test results. (a) The licensee testing facility shall...

Predictive test for chemotherapy response in resectable gastric cancer: a multi-cohort, retrospective analysis.

PubMed

Cheong, Jae-Ho; Yang, Han-Kwang; Kim, Hyunki; Kim, Woo Ho; Kim, Young-Woo; Kook, Myeong-Cherl; Park, Young-Kyu; Kim, Hyung-Ho; Lee, Hye Seung; Lee, Kyung Hee; Gu, Mi Jin; Kim, Ha Yan; Lee, Jinae; Choi, Seung Ho; Hong, Soonwon; Kim, Jong Won; Choi, Yoon Young; Hyung, Woo Jin; Jang, Eunji; Kim, Hyeseon; Huh, Yong-Min; Noh, Sung Hoon

2018-05-01

Adjuvant chemotherapy after surgery improves survival of patients with stage II-III, resectable gastric cancer. However, the overall survival benefit observed after adjuvant chemotherapy is moderate, suggesting that not all patients with resectable gastric cancer treated with adjuvant chemotherapy benefit from it. We aimed to develop and validate a predictive test for adjuvant chemotherapy response in patients with resectable, stage II-III gastric cancer. In this multi-cohort, retrospective study, we developed through a multi-step strategy a predictive test consisting of two rule-based classifier algorithms with predictive value for adjuvant chemotherapy response and prognosis. Exploratory bioinformatics analyses identified biologically relevant candidate genes in gastric cancer transcriptome datasets. In the discovery analysis, a four-gene, real-time RT-PCR assay was developed and analytically validated in formalin-fixed, paraffin-embedded (FFPE) tumour tissues from an internal cohort of 307 patients with stage II-III gastric cancer treated at the Yonsei Cancer Center with D2 gastrectomy plus adjuvant fluorouracil-based chemotherapy (n=193) or surgery alone (n=114). The same internal cohort was used to evaluate the prognostic and chemotherapy response predictive value of the single patient classifier genes using associations with 5-year overall survival. The results were validated with a subset (n=625) of FFPE tumour samples from an independent cohort of patients treated in the CLASSIC trial (NCT00411229), who received D2 gastrectomy plus capecitabine and oxaliplatin chemotherapy (n=323) or surgery alone (n=302). The primary endpoint was 5-year overall survival. We identified four classifier genes related to relevant gastric cancer features (GZMB, WARS, SFRP4, and CDX1) that formed the single patient classifier assay. In the validation cohort, the prognostic single patient classifier (based on the expression of GZMB, WARS, and SFRP4) identified 79 (13%) of 625

Initial validation and results of the Symptoms in Persons At Risk of Rheumatoid Arthritis (SPARRA) questionnaire: a EULAR project

PubMed Central

van Beers-Tas, Marian H; ter Wee, Marieke M; van Tuyl, Lilian H; Maat, Bertha; Hoogland, Wijnanda; Hensvold, Aase H; Catrina, Anca I; Mosor, Erika; Finckh, Axel; Courvoisier, Delphine S; Filer, Andrew; Sahbudin, Ilfita; Stack, Rebecca J; Raza, Karim; van Schaardenburg, Dirkjan

2018-01-01

Objectives To describe the development and assess the psychometric properties of the novel ‘Symptoms in Persons At Risk of Rheumatoid Arthritis’ (SPARRA) questionnaire in individuals at risk of rheumatoid arthritis (RA) and to quantify their symptoms. Methods The questionnaire items were derived from a qualitative study in patients with seropositive arthralgia. The questionnaire was administered to 219 individuals at risk of RA on the basis of symptoms or autoantibody positivity: 74% rheumatoid factor and/or anticitrullinated protein antibodies positive, 26% seronegative. Validity, reliability and responsiveness were assessed. Eighteen first degree relatives (FDR) of patients with RA were used for comparison. Results Face and content validity were high. The test-retest showed good agreement and reliability (1 week and 6 months). Overall, construct validity was low to moderate, with higher values for concurrent validity, suggesting that some questions reflect symptom content not captured with regular Visual Analogue Scale pain/well-being. Responsiveness was low (small subgroup). Finally, the burden of symptoms in both seronegative and seropositive at risk individuals was high, with pain, stiffness and fatigue being the most common ones with a major impact on daily functioning. The FDR cohort (mostly healthy individuals) showed a lower burden of symptoms; however, the distribution of symptoms was similar. Conclusions The SPARRA questionnaire has good psychometric properties and can add information to currently available clinical measures in individuals at risk of RA. The studied group had a high burden and impact of symptoms. Future studies should evaluate whether SPARRA data can improve the prediction of RA in at risk individuals.

Red Meat Consumption and Mortality: Results from Two Prospective Cohort Studies

PubMed Central

Pan, An; Sun, Qi; Bernstein, Adam M.; Schulze, Matthias B.; Manson, JoAnn E.; Stampfer, Meir J.; Willett, Walter C.; Hu, Frank B.

2013-01-01

Background Red meat consumption has been associated with an increased risk of chronic diseases. However, its relationship with mortality remains uncertain. Methods We prospectively followed 37698 men from the Health Professionals Follow-up Study (1986-2008) and 83644 women from the Nurses' Health Study (1980-2008), who were free of cardiovascular disease (CVD) and cancer at baseline. Diet was assessed by validated food-frequency questionnaires and updated every four years. Results We documented 23926 deaths (including 5910 CVD and 9464 cancer deaths) during 2.96 million person-years of follow-up. After multivariate adjustment for major lifestyle and dietary risk factors, the pooled hazard ratio (HR) and 95% confidence interval of total mortality was 1.13 (1.07-1.20) for 1-serving per day increase of unprocessed red meat, 1.20 (1.15-1.24) for processed red meat. The corresponding HRs were 1.18 (1.13-1.23) and 1.21 (1.13-1.31) for CVD mortality, 1.10 (1.06-1.14) and 1.16 (1.09-1.23) for cancer mortality. We estimated that substitutions of 1-serving per day of other foods (including fish, poultry, nuts, legumes, low-fat dairy, and whole grains) for 1-serving per day of red meat were associated with a 7%-19% lower mortality risk. We also estimated that 9.3% of deaths in men and 7.6% in women in our cohorts could be prevented at the end of follow-up if all individuals consumed <0.5 serving/d (≈42 g/d) of red meat. Conclusions Red meat consumption is associated with an increased risk of total, CVD and cancer mortality. Substitution of other healthy protein sources for red meat is associated with a lower mortality risk. PMID:22412075

Validity of a new food frequency questionnaire for pregnant women in the Norwegian Mother and Child Cohort Study (MoBa).

PubMed

Brantsaeter, Anne Lise; Haugen, Margaretha; Alexander, Jan; Meltzer, Helle Margrete

2008-01-01

The aim of the present study was to examine the relative validity of foods and nutrients calculated by a new food frequency questionnaire (FFQ) in the Norwegian Mother and Child Cohort Study (MoBa). Reference measures were a 4-day weighed food diary (FD), a motion sensor for measuring total energy expenditure, one 24-h urine collection for analysis of nitrogen and iodine excretion, and a venous blood specimen for analysis of plasma 25-hydroxy-vitamin D and serum folate. A total of 119 women participated in the validation study, and 112 completed the motion sensor registration. Overall, the level of agreement between the FFQ and the FD was satisfactory, and significant correlations were found for all major food groups and for all nutrients except vitamin E. The average correlation coefficient between the FFQ and the FD for daily intake was 0.48 for foods and 0.36 for nutrients, and on average, 68% of the participants were classified into the same or adjacent quintiles by the two methods. Estimated total energy expenditure indicated that under-reporting of energy intake was more extensive with the FD than with the FFQ. The biological markers confirmed that the FFQ was able to distinguish between high and low intakes of nutrients, as measured by vitamin D, folate, protein and iodine. This validation study indicates that the MoBa FFQ produces reasonable valid intake estimates and is a valid tool to rank pregnant women according to low and high intakes of energy, nutrients and foods.

Validation of the Long-term Difficulties Inventory (LDI) and the List of Threatening Experiences (LTE) as measures of stress in epidemiological population-based cohort studies.

PubMed

Rosmalen, J G M; Bos, E H; de Jonge, P

2012-12-01

Stress questionnaires are included in many epidemiological cohort studies but the psychometric characteristics of these questionnaires are largely unknown. The aim of this study was to describe these characteristics for two short questionnaires measuring the lifetime and past year occurrence of stress: the List of Threatening Events (LTE) as a measure of acute stress and the Long-term Difficulties Inventory (LDI) as a measure of chronic stress. This study was performed in a general population cohort consisting of 588 females (53.7%) and 506 males (46.3%), with a mean age of 53.5 years (s.d.=11.3 years). Respondents completed the LTE and the LDI for the past year, and for the age categories of 0-12, 13-18, 19-39, 40-60, and >60 years. They also completed questionnaires on perceived stress, psychological distress (the General Health Questionnaire, GHQ-12), anxiety and depression (the Symptom Checklist, SCL-8) and neuroticism (the Eysenck Personality Questionnaire - Revised Short Scale, EPQ-RSS-N). Approximately 2 years later, 976 respondents (89%) completed these questionnaires for a second time. The stability of the retrospective reporting of long-term difficulties and life events was satisfactory: 0.7 for the lifetime LDI and 0.6 for the lifetime LTE scores. The construct validity of these lists is indicated by their positive associations with psychological distress, mental health problems and neuroticism. This study in a large population-based sample shows that the LDI and LTE have sufficient validity and stability to include them in major epidemiological cohort studies.

Results and current status of the NPARC alliance validation effort

NASA Technical Reports Server (NTRS)

Towne, Charles E.; Jones, Ralph R.

1996-01-01

The NPARC Alliance is a partnership between the NASA Lewis Research Center (LeRC) and the USAF Arnold Engineering Development Center (AEDC) dedicated to the establishment of a national CFD capability, centered on the NPARC Navier-Stokes computer program. The three main tasks of the Alliance are user support, code development, and validation. The present paper is a status report on the validation effort. It describes the validation approach being taken by the Alliance. Representative results are presented for laminar and turbulent flat plate boundary layers, a supersonic axisymmetric jet, and a glancing shock/turbulent boundary layer interaction. Cases scheduled to be run in the future are also listed. The archive of validation cases is described, including information on how to access it via the Internet.

Clinical Nomograms to Predict Stone-Free Rates after Shock-Wave Lithotripsy: Development and Internal-Validation

PubMed Central

Kim, Jung Kwon; Ha, Seung Beom; Jeon, Chan Hoo; Oh, Jong Jin; Cho, Sung Yong; Oh, Seung-June; Kim, Hyeon Hoe; Jeong, Chang Wook

2016-01-01

Purpose Shock-wave lithotripsy (SWL) is accepted as the first line treatment modality for uncomplicated upper urinary tract stones; however, validated prediction models with regards to stone-free rates (SFRs) are still needed. We aimed to develop nomograms predicting SFRs after the first and within the third session of SWL. Computed tomography (CT) information was also modeled for constructing nomograms. Materials and Methods From March 2006 to December 2013, 3028 patients were treated with SWL for ureter and renal stones at our three tertiary institutions. Four cohorts were constructed: Total-development, Total-validation, CT-development, and CT-validation cohorts. The nomograms were developed using multivariate logistic regression models with selected significant variables in a univariate logistic regression model. A C-index was used to assess the discrimination accuracy of nomograms and calibration plots were used to analyze the consistency of prediction. Results The SFR, after the first and within the third session, was 48.3% and 68.8%, respectively. Significant variables were sex, stone location, stone number, and maximal stone diameter in the Total-development cohort, and mean Hounsfield unit (HU) and grade of hydronephrosis (HN) were additional parameters in the CT-development cohort. The C-indices were 0.712 and 0.723 for after the first and within the third session of SWL in the Total-development cohort, and 0.755 and 0.756, in the CT-development cohort, respectively. The calibration plots showed good correspondences. Conclusions We constructed and validated nomograms to predict SFR after SWL. To the best of our knowledge, these are the first graphical nomograms to be modeled with CT information. These may be useful for patient counseling and treatment decision-making. PMID:26890006

Integration of copy number and transcriptomics provides risk stratification in prostate cancer: A discovery and validation cohort study

PubMed Central

Ross-Adams, H.; Lamb, A.D.; Dunning, M.J.; Halim, S.; Lindberg, J.; Massie, C.M.; Egevad, L.A.; Russell, R.; Ramos-Montoya, A.; Vowler, S.L.; Sharma, N.L.; Kay, J.; Whitaker, H.; Clark, J.; Hurst, R.; Gnanapragasam, V.J.; Shah, N.C.; Warren, A.Y.; Cooper, C.S.; Lynch, A.G.; Stark, R.; Mills, I.G.; Grönberg, H.; Neal, D.E.

2015-01-01

Background Understanding the heterogeneous genotypes and phenotypes of prostate cancer is fundamental to improving the way we treat this disease. As yet, there are no validated descriptions of prostate cancer subgroups derived from integrated genomics linked with clinical outcome. Methods In a study of 482 tumour, benign and germline samples from 259 men with primary prostate cancer, we used integrative analysis of copy number alterations (CNA) and array transcriptomics to identify genomic loci that affect expression levels of mRNA in an expression quantitative trait loci (eQTL) approach, to stratify patients into subgroups that we then associated with future clinical behaviour, and compared with either CNA or transcriptomics alone. Findings We identified five separate patient subgroups with distinct genomic alterations and expression profiles based on 100 discriminating genes in our separate discovery and validation sets of 125 and 103 men. These subgroups were able to consistently predict biochemical relapse (p = 0.0017 and p = 0.016 respectively) and were further validated in a third cohort with long-term follow-up (p = 0.027). We show the relative contributions of gene expression and copy number data on phenotype, and demonstrate the improved power gained from integrative analyses. We confirm alterations in six genes previously associated with prostate cancer (MAP3K7, MELK, RCBTB2, ELAC2, TPD52, ZBTB4), and also identify 94 genes not previously linked to prostate cancer progression that would not have been detected using either transcript or copy number data alone. We confirm a number of previously published molecular changes associated with high risk disease, including MYC amplification, and NKX3-1, RB1 and PTEN deletions, as well as over-expression of PCA3 and AMACR, and loss of MSMB in tumour tissue. A subset of the 100 genes outperforms established clinical predictors of poor prognosis (PSA, Gleason score), as well as previously published gene

Validation of the Oxford classification of IgA nephropathy in cohorts with different presentations and treatments

PubMed Central

Coppo, Rosanna; Troyanov, Stéphan; Bellur, Shubha; Cattran, Daniel; Cook, H Terence; Feehally, John; Roberts, Ian S D; Morando, Laura; Camilla, Roberta; Tesar, Vladimir; Lunberg, Sigrid; Gesualdo, Loreto; Emma, Francesco; Rollino, Cristiana; Amore, Alessandro; Praga, Manuel; Feriozzi, Sandro; Segoloni, Giuseppe; Pani, Antonello; Cancarini, Giovanni; Durlik, Magalena; Moggia, Elisabetta; Mazzucco, Gianna; Giannakakis, Costantinos; Honsova, Eva; Sundelin, B Brigitta; Di Palma, Anna Maria; Ferrario, Franco; Gutierrez, Eduardo; Asunis, Anna Maria; Barratt, Jonathan; Tardanico, Regina; Perkowska-Ptasinska, Agnieszka

2014-01-01

The Oxford Classification of IgA Nephropathy (IgAN) identified mesangial hypercellularity (M), endocapillary proliferation (E), segmental glomerulosclerosis (S), and tubular atrophy/interstitial fibrosis (T) as independent predictors of outcome. Whether it applies to individuals excluded from the original study and how therapy influences the predictive value of pathology remain uncertain. The VALIGA study examined 1147 patients from 13 European countries that encompassed the whole spectrum of IgAN. Over a median follow-up of 4.7 years, 86% received renin–angiotensin system blockade and 42% glucocorticoid/immunosuppressive drugs. M, S, and T lesions independently predicted the loss of estimated glomerular filtration rate (eGFR) and a lower renal survival. Their value was also assessed in patients not represented in the Oxford cohort. In individuals with eGFR less than 30 ml/min per 1.73 m2, the M and T lesions independently predicted a poor survival. In those with proteinuria under 0.5 g/day, both M and E lesions were associated with a rise in proteinuria to 1 or 2 g/day or more. The addition of M, S, and T lesions to clinical variables significantly enhanced the ability to predict progression only in those who did not receive immunosuppression (net reclassification index 11.5%). The VALIGA study provides a validation of the Oxford classification in a large European cohort of IgAN patients across the whole spectrum of the disease. The independent predictive value of pathology MEST score is reduced by glucocorticoid/immunosuppressive therapy. PMID:24694989

Validation of an accelerated high-sensitivity troponin T assay protocol in an Australian cohort with chest pain.

PubMed

Parsonage, William A; Greenslade, Jaimi H; Hammett, Christopher J; Lamanna, Arvin; Tate, Jillian R; Ungerer, Jacobus P; Chu, Kevin; Than, Martin; Brown, Anthony F T; Cullen, Louise

2014-02-17

To validate an accelerated biomarker strategy using a high-sensitivity cardiac troponin T (hs-cTnT) assay for diagnosing acute myocardial infarction (AMI) in patients presenting to the emergency department with chest pain; and to validate this strategy in combination with the National Heart Foundation of Australia/Cardiac Society of Australia and New Zealand risk stratification model. Single-centre, prospective, observational cohort study of 764 adults presenting to a tertiary hospital with symptoms of possible acute coronary syndrome between November 2008 and February 2011. AMI or cardiac death within 24 hours of presentation (primary), and major adverse cardiac events within 30 days (secondary). An elevated hs-cTnT assay result above the 99th percentile at either the 0 h or 2 h time points had sensitivity of 96.4% (95% CI, 87.9%-99.0%), specificity of 82.6% (95% CI, 79.7%-85.2%), negative predictive value of 99.7% (95% CI, 98.8%-99.9%) and positive predictive value of 30.5% (95% CI, 24.2%-37.6%) for diagnosing AMI. Compared with a traditional 6 h cardiac troponin testing strategy, the accelerated strategy led to reclassification of risk in only two patients with adverse cardiac outcomes, with no net effect on appropriate management. In patients presenting with chest pain, an accelerated biomarker strategy using the hs-cTnT assay performed well in the initial diagnosis of AMI. The accelerated strategy was also effective when incorporated into a comprehensive strategy of risk stratification that included clinical and demographic factors. The time saved by this approach could have a major impact on health service delivery. Australian New Zealand Clinical Trials Registry ACTRN12610000053022.

42 CFR 478.15 - QIO review of changes resulting from DRG validation.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 4 2010-10-01 2010-10-01 false QIO review of changes resulting from DRG validation... review of changes resulting from DRG validation. (a) General rules. (1) A provider or practitioner dissatisfied with a change to the diagnostic or procedural coding information made by a QIO as a result of DRG...

[Validation of the IBS-SSS].

PubMed

Betz, C; Mannsdörfer, K; Bischoff, S C

2013-10-01

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder characterised by abdominal pain, associated with stool abnormalities and changes in stool consistency. Diagnosis of IBS is based on characteristic symptoms and exclusion of other gastrointestinal diseases. A number of questionnaires exist to assist diagnosis and assessment of severity of the disease. One of these is the irritable bowel syndrome - severity scoring system (IBS-SSS). The IBS-SSS was validated 1997 in its English version. In the present study, the IBS-SSS has been validated in German language. To do this, a cohort of 60 patients with IBS according to the Rome III criteria, was compared with a control group of healthy individuals (n = 38). We studied sensitivity and reproducibility of the score, as well as the sensitivity to detect changes of symptom severity. The results of the German validation largely reflect the results of the English validation. The German version of the IBS-SSS is also a valid, meaningful and reproducible questionnaire with a high sensitivity to assess changes in symptom severity, especially in IBS patients with moderate symptoms. It is unclear if the IBS-SSS is also a valid questionnaire in IBS patients with severe symptoms because this group of patients was not studied. © Georg Thieme Verlag KG Stuttgart · New York.

[Multicentre, prospective cohort study, to validate the Italian version of the Braden Q scale for the risk of the pressure sores in newborns and up to 8 years old children].

PubMed

Chiari, Paolo; Poli, Marco; Magli, Claudia; Bascelli, Emanuele; Rocchi, Roberto; Bolognini, Silvia; Tartari, Piero; Armuzzi, Roberta; Rossi, Gianna; Peghetti, Angela; Biavati, Catia; Fontana, Mirella; Gazineo, Domenica; Cordella, Simona; Tiozzo, Emanuela; Ciliento, Gaetano; Carta, Giovanna; Taddia, Patrizia

2012-01-01

Multicenter prospective cohort study, to validate the Italian version of the Braden Q scale for the risk of pressure sores in newborns and up to 8 years old children. Children admitted to Intensive care Units (ICU), oncology and neurology/neurosurgery wards are at risk of developing pressure sores. To validate the Italian version of the Braden Q scale for the assessment of the risk of developing pressure sores in children. Children from 21 days to 8 years, admitted to intensive and sub intensive units were recruited. Premature babies, children admitted with a pressure sore and with a story of congenital cardiomiopathy were excluded. In this cohort, multicentre and with repeated measurements study, the first assessment was performed after 24 hours from hospital admission, using the Braden Q Scale (Suddaby's version). The pressure sores were assessed with the Skin assessment Tool and staged according to the National Pressure Ulcer Advisory Panel. RESULTS. On the 157 children 524 observation were conducted. The incidence of pressure sores was 17.2%. Only the analysis on specific subgroups of patients showed a good diagnostic accuracy: 71.4% on children 3-8 years; 85.6% in sub intensive wards. The Braden Q scale may be reliably used and shows a good diagnostic accuracy in children 3-8 years of age admitted to sub-intensive, neurology, oncology and heamatology wards.

Environmental exposure assessment in European birth cohorts: results from the ENRIECO project

PubMed Central

2013-01-01

Environmental exposures during pregnancy and early life may have adverse health effects. Single birth cohort studies often lack statistical power to tease out such effects reliably. To improve the use of existing data and to facilitate collaboration among these studies, an inventory of the environmental exposure and health data in these studies was made as part of the ENRIECO (Environmental Health Risks in European Birth Cohorts) project. The focus with regard to exposure was on outdoor air pollution, water contamination, allergens and biological organisms, metals, pesticides, smoking and second hand tobacco smoke (SHS), persistent organic pollutants (POPs), noise, radiation, and occupational exposures. The review lists methods and data on environmental exposures in 37 European birth cohort studies. Most data is currently available for smoking and SHS (N=37 cohorts), occupational exposures (N=33), outdoor air pollution, and allergens and microbial agents (N=27). Exposure modeling is increasingly used for long-term air pollution exposure assessment; biomonitoring is used for assessment of exposure to metals, POPs and other chemicals; and environmental monitoring for house dust mite exposure assessment. Collaborative analyses with data from several birth cohorts have already been performed successfully for outdoor air pollution, water contamination, allergens, biological contaminants, molds, POPs and SHS. Key success factors for collaborative analyses are common definitions of main exposure and health variables. Our review emphasizes that such common definitions need ideally be arrived at in the study design phase. However, careful comparison of methods used in existing studies also offers excellent opportunities for collaborative analyses. Investigators can use this review to evaluate the potential for future collaborative analyses with respect to data availability and methods used in the different cohorts and to identify potential partners for a specific research

THE PRENATAL PARENTAL REFLECTIVE FUNCTIONING QUESTIONNAIRE: EXPLORING FACTOR STRUCTURE AND CONSTRUCT VALIDITY OF A NEW MEASURE IN THE FINN BRAIN BIRTH COHORT PILOT STUDY.

PubMed

Pajulo, Marjukka; Tolvanen, Mimmi; Karlsson, Linnea; Halme-Chowdhury, Elina; Öst, Camilla; Luyten, Patrick; Mayes, Linda; Karlsson, Hasse

2015-01-01

Parental reflective functioning (PRF) is the capacity to focus on experience and feelings in oneself and in the child. Individual differences in PRF reportedly affect child attachment and socioemotional development. In this study, we report work on developing a questionnaire to assess PRF during pregnancy (Prenatal Parental Reflective Functioning Questionnaire; P-PRFQ). The factor structure of the 33-item version of the P-PRFQ was explored using pilot study data from the Finn Brain Birth Cohort Study (n = 124 mothers, n = 82 fathers). Construct validity was assessed against the Pregnancy Interview (PI; A. Slade, L. Grunebaum, L. Huganir, & M. Reeves, 1987, 2002, 2011) in a subsample of 29 mothers from the same pilot sample. Exploratory and confirmatory factor analysis resulted in a 14-item P-PRFQ, with three factors which seem to capture relevant aspects of prenatal parental mentalization-F1: "Opacity of mental states," F2: "Reflecting on the fetus-child," and F3: "The dynamic nature of the mental states." Functioning of the factor structure was further tested in the large cohort with 600 mothers and 600 fathers. Correlations with the PI result were high, both regarding total and factor scores of the P-PRFQ. Cost-effective tools to assess key areas of early parenting are needed for both research and clinical purposes. The 14-item P-PRFQ seems to be an applicable and promising new tool for assessing very early parental mentalizing capacity. © 2015 Michigan Association for Infant Mental Health.

Development and validation of a risk assessment tool for gastric cancer in a general Japanese population.

PubMed

Iida, Masahiro; Ikeda, Fumie; Hata, Jun; Hirakawa, Yoichiro; Ohara, Tomoyuki; Mukai, Naoko; Yoshida, Daigo; Yonemoto, Koji; Esaki, Motohiro; Kitazono, Takanari; Kiyohara, Yutaka; Ninomiya, Toshiharu

2018-05-01

There have been very few reports of risk score models for the development of gastric cancer. The aim of this study was to develop and validate a risk assessment tool for discerning future gastric cancer risk in Japanese. A total of 2444 subjects aged 40 years or over were followed up for 14 years from 1988 (derivation cohort), and 3204 subjects of the same age group were followed up for 5 years from 2002 (validation cohort). The weighting (risk score) of each risk factor for predicting future gastric cancer in the risk assessment tool was determined based on the coefficients of a Cox proportional hazards model in the derivation cohort. The goodness of fit of the established risk assessment tool was assessed using the c-statistic and the Hosmer-Lemeshow test in the validation cohort. During the follow-up, gastric cancer developed in 90 subjects in the derivation cohort and 35 subjects in the validation cohort. In the derivation cohort, the risk prediction model for gastric cancer was established using significant risk factors: age, sex, the combination of Helicobacter pylori antibody and pepsinogen status, hemoglobin A1c level, and smoking status. The incidence of gastric cancer increased significantly as the sum of risk scores increased (P trend < 0.001). The risk assessment tool was validated internally and showed good discrimination (c-statistic = 0.76) and calibration (Hosmer-Lemeshow test P = 0.43) in the validation cohort. We developed a risk assessment tool for gastric cancer that provides a useful guide for stratifying an individual's risk of future gastric cancer.

External validation of preexisting first trimester preeclampsia prediction models.

PubMed

Allen, Rebecca E; Zamora, Javier; Arroyo-Manzano, David; Velauthar, Luxmilar; Allotey, John; Thangaratinam, Shakila; Aquilina, Joseph

2017-10-01

To validate the increasing number of prognostic models being developed for preeclampsia using our own prospective study. A systematic review of literature that assessed biomarkers, uterine artery Doppler and maternal characteristics in the first trimester for the prediction of preeclampsia was performed and models selected based on predefined criteria. Validation was performed by applying the regression coefficients that were published in the different derivation studies to our cohort. We assessed the models discrimination ability and calibration. Twenty models were identified for validation. The discrimination ability observed in derivation studies (Area Under the Curves) ranged from 0.70 to 0.96 when these models were validated against the validation cohort, these AUC varied importantly, ranging from 0.504 to 0.833. Comparing Area Under the Curves obtained in the derivation study to those in the validation cohort we found statistically significant differences in several studies. There currently isn't a definitive prediction model with adequate ability to discriminate for preeclampsia, which performs as well when applied to a different population and can differentiate well between the highest and lowest risk groups within the tested population. The pre-existing large number of models limits the value of further model development and future research should be focussed on further attempts to validate existing models and assessing whether implementation of these improves patient care. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Pitfalls in Prediction Modeling for Normal Tissue Toxicity in Radiation Therapy: An Illustration With the Individual Radiation Sensitivity and Mammary Carcinoma Risk Factor Investigation Cohorts

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

Mbah, Chamberlain, E-mail: chamberlain.mbah@ugent.be; Department of Mathematical Modeling, Statistics, and Bioinformatics, Faculty of Bioscience Engineering, Ghent University, Ghent; Thierens, Hubert

Purpose: To identify the main causes underlying the failure of prediction models for radiation therapy toxicity to replicate. Methods and Materials: Data were used from two German cohorts, Individual Radiation Sensitivity (ISE) (n=418) and Mammary Carcinoma Risk Factor Investigation (MARIE) (n=409), of breast cancer patients with similar characteristics and radiation therapy treatments. The toxicity endpoint chosen was telangiectasia. The LASSO (least absolute shrinkage and selection operator) logistic regression method was used to build a predictive model for a dichotomized endpoint (Radiation Therapy Oncology Group/European Organization for the Research and Treatment of Cancer score 0, 1, or ≥2). Internal areas undermore » the receiver operating characteristic curve (inAUCs) were calculated by a naïve approach whereby the training data (ISE) were also used for calculating the AUC. Cross-validation was also applied to calculate the AUC within the same cohort, a second type of inAUC. Internal AUCs from cross-validation were calculated within ISE and MARIE separately. Models trained on one dataset (ISE) were applied to a test dataset (MARIE) and AUCs calculated (exAUCs). Results: Internal AUCs from the naïve approach were generally larger than inAUCs from cross-validation owing to overfitting the training data. Internal AUCs from cross-validation were also generally larger than the exAUCs, reflecting heterogeneity in the predictors between cohorts. The best models with largest inAUCs from cross-validation within both cohorts had a number of common predictors: hypertension, normalized total boost, and presence of estrogen receptors. Surprisingly, the effect (coefficient in the prediction model) of hypertension on telangiectasia incidence was positive in ISE and negative in MARIE. Other predictors were also not common between the 2 cohorts, illustrating that overcoming overfitting does not solve the problem of replication failure of prediction models completely

Validity of the SAT® for Predicting First-Year Grades: 2010 SAT Validity Sample. Statistical Report 2013-2

ERIC Educational Resources Information Center

Patterson, Brian F.; Mattern, Krista D.

2013-01-01

The continued accumulation of validity evidence for the core uses of educational assessments is critical to ensure that proper inferences will be made for those core purposes. To that end, the College Board has continued to follow previous cohorts of college students and this report provides updated validity evidence for using the SAT to predict…

Validation of the psychometrics properties of a French quality of life questionnaire among a cohort of renal transplant recipients less than one year.

PubMed

Beauger, Davy; Fruit, Dorothée; Villeneuve, Claire; Laroche, Marie-Laure; Jouve, Elisabeth; Rousseau, Annick; Boyer, Laurent; Gentile, Stéphanie

2016-09-01

Renal transplantation is considered as the treatment of choice for patients with end-stage renal disease. Health-related quality of life (HRQoL) of renal transplant recipients (RTR) is very important to assess, especially during the first year after transplantation. To provide new evidence about the suitability of HRQoL measures in RTR during the first post-transplant year, we explored the internal structure, reliability and external validity of a French specific HRQoL instrument, the Renal Transplant Quality of life Questionnaire Second Version (RTQ V2). The data were issued from the French multicenter cohort of renal transplant patients followed during 4 years (EPIGREN). The HRQoL of RTR was assessed five times (at 1, 3, 6, 9 and 12 months after transplantation) with the RTQ V2, a specific instrument consisting of 32 items describing five dimensions. Socio-demographic information, clinical characteristics and HRQoL (i.e., RTQ V2 and SF-36) were collected. For the five times, psychometric properties of the RTQ V2 were compared to those reported from the reference population assessed in the validation study. Three hundred and thirty-four patients were enrolled. The proportions of well-projected items, item-internal consistency, item-discriminant validity, floor and ceiling effects, Cronbach's alpha coefficients and item goodness-of-fit statistics were satisfactory for each dimension at the five times of the study. The suitability indices of construct validity were higher than 90 % for each time (minimum-maximum: 90.8-97.4 %). The external validity was less satisfactory, with a suitability indices ranged from 46.7 % at M1 to 66.7 % at M12. However, the discrepancies with the reference population (mainly for the gender) appeared logical considering the scientific literature on HRQoL of RTR during the first post-transplant year and may not compromise the external validity. These results support the validity and reliability of the RTQ V2 for evaluating HRQoL in

Results and Validation of MODIS Aerosol Retrievals Over Land and Ocean

NASA Technical Reports Server (NTRS)

Remer, Lorraine; Einaudi, Franco (Technical Monitor)

2001-01-01

The MODerate Resolution Imaging Spectroradiometer (MODIS) instrument aboard the Terra spacecraft has been retrieving aerosol parameters since late February 2000. Initial qualitative checking of the products showed very promising results including matching of land and ocean retrievals at coastlines. Using AERONET ground-based radiometers as our primary validation tool, we have established quantitative validation as well. Our results show that for most aerosol types, the MODIS products fall within the pre-launch estimated uncertainties. Surface reflectance and aerosol model assumptions appear to be sufficiently accurate for the optical thickness retrieval. Dust provides a possible exception, which may be due to non-spherical effects. Over ocean the MODIS products include information on particle size, and these parameters are also validated with AERONET retrievals.

Results and Validation of MODIS Aerosol Retrievals over Land and Ocean

NASA Technical Reports Server (NTRS)

Remer, L. A.; Kaufman, Y. J.; Tanre, D.; Ichoku, C.; Chu, D. A.; Mattoo, S.; Levy, R.; Martins, J. V.; Li, R.-R.; Einaudi, Franco (Technical Monitor)

2000-01-01

The MODerate Resolution Imaging Spectroradiometer (MODIS) instrument aboard the Terra spacecraft has been retrieving aerosol parameters since late February 2000. Initial qualitative checking of the products showed very promising results including matching of land and ocean retrievals at coastlines. Using AERONET ground-based radiometers as our primary validation tool, we have established quantitative validation as well. Our results show that for most aerosol types, the MODIS products fall within the pre-launch estimated uncertainties. Surface reflectance and aerosol model assumptions appear to be sufficiently accurate for the optical thickness retrieval. Dust provides a possible exception, which may be due to non-spherical effects. Over ocean the MODIS products include information on particle size, and these parameters are also validated with AERONET retrievals.

Development and validation of electronic surveillance tool for acute kidney injury: A retrospective analysis.

PubMed

Ahmed, Adil; Vairavan, Srinivasan; Akhoundi, Abbasali; Wilson, Gregory; Chiofolo, Caitlyn; Chbat, Nicolas; Cartin-Ceba, Rodrigo; Li, Guangxi; Kashani, Kianoush

2015-10-01

Timely detection of acute kidney injury (AKI) facilitates prevention of its progress and potentially therapeutic interventions. The study objective is to develop and validate an electronic surveillance tool (AKI sniffer) to detect AKI in 2 independent retrospective cohorts of intensive care unit (ICU) patients. The primary aim is to compare the sensitivity, specificity, and positive and negative predictive values of AKI sniffer performance against a reference standard. This study is conducted in the ICUs of a tertiary care center. The derivation cohort study subjects were Olmsted County, MN, residents admitted to all Mayo Clinic ICUs from July 1, 2010, through December 31, 2010, and the validation cohort study subjects were all patients admitted to a Mayo Clinic, Rochester, campus medical/surgical ICU on January 12, 2010, through March 23, 2010. All included records were reviewed by 2 independent investigators who adjudicated AKI using the Acute Kidney Injury Network criteria; disagreements were resolved by a third reviewer. This constituted the reference standard. An electronic algorithm was developed; its precision and reliability were assessed in comparison with the reference standard in 2 separate cohorts, derivation and validation. Of 1466 screened patients, a total of 944 patients were included in the study: 482 for derivation and 462 for validation. Compared with the reference standard in the validation cohort, the sensitivity and specificity of the AKI sniffer were 88% and 96%, respectively. The Cohen κ (95% confidence interval) agreement between the electronic and the reference standard was 0.84 (0.78-0.89) and 0.85 (0.80-0.90) in the derivation and validation cohorts. Acute kidney injury can reliably and accurately be detected electronically in ICU patients. The presented method is applicable for both clinical (decision support) and research (enrollment for clinical trials) settings. Prospective validation is required. Copyright © 2015 Elsevier Inc. All

Intakes of caffeine, coffee and tea and risk of amyotrophic lateral sclerosis: Results from five cohort studies.

PubMed

Fondell, Elinor; O'Reilly, É Ilis J; Fitzgerald, Kathryn C; Falcone, Guido J; Kolonel, Laurence N; Park, Yikyung; Gapstur, Susan M; Ascherio, Alberto

2015-01-01

Caffeine is thought to be neuroprotective by antagonizing the adenosine A2A receptors in the brain and thereby protecting motor neurons from excitotoxicity. We examined the association between consumption of caffeine, coffee and tea and risk of amyotrophic lateral sclerosis (ALS). Longitudinal analyses based on over 1,010,000 males and females in five large cohort studies (the Nurses' Health Study, the Health Professionals Follow-up Study, the Cancer Prevention Study II Nutrition Cohort, the Multiethnic Cohort Study, and the National Institutes of Health-AARP Diet and Health Study). Cohort-specific multivariable-adjusted risk ratios (RR) and 95% confidence intervals (CI) estimates of ALS incidence or death were estimated by Cox proportional hazards regression and pooled using random-effects models. Results showed that a total of 1279 cases of ALS were documented during a mean of 18 years of follow-up. Caffeine intake was not associated with ALS risk; the pooled multivariable-adjusted RR comparing the highest to the lowest quintile of intake was 0.96 (95% CI 0.81-1.16). Similarly, neither coffee nor tea was associated with ALS risk. In conclusion, the results of this large study do not support associations of caffeine or caffeinated beverages with ALS risk.

Intakes of caffeine, coffee and tea and risk of Amyotrophic Lateral Sclerosis: Results from five cohort studies

PubMed Central

Fondell, Elinor; O'Reilly, Éilis J.; Fitzgerald, Kathryn C.; Falcone, Guido J.; Kolonel, Laurence N.; Park, Yikyung; Gapstur, Susan M.; Ascherio, Alberto

2015-01-01

Objective Caffeine is thought to be neuroprotective by antagonizing the adenosine A2A receptors in the brain and thereby protecting motor neurons from excitotoxicity. We examined the association between consumption of caffeine, coffee and tea and risk of Amyotrophic Lateral Sclerosis (ALS). Methods Longitudinal analyses based on over 1 010 000 men and women in 5 large cohort studies [the Nurses’ Health Study, the Health Professionals Follow-up Study, the Cancer Prevention Study II Nutrition Cohort, the Multiethnic Cohort Study, and the National Institutes of Health – AARP Diet and Health Study]. Cohort-specific multivariable-adjusted risk ratios (RR) and 95% confidence intervals (CI) estimates of ALS incidence or death was estimated by Cox proportional hazards regression and pooled using random-effects models. Results A total of 1279 cases of ALS were documented during a mean of 18 years of follow-up. Caffeine intake was not associated with ALS risk; the pooled multivariable-adjusted RR comparing the highest to the lowest quintile of intake was 0.96 (95% CI 0.81-1.16). Similarly, neither coffee nor tea was associated with ALS risk. Conclusion The results of this large study do not support associations of caffeine or caffeinated beverages with ALS risk. PMID:25822002

Efficacy of hip resurfacing arthroplasty: 6 year results from an international multisurgeon prospective cohort study.

PubMed

Aulakh, Tajeshwar S; Jayasekera, Narlaka; Singh, Rohit; Patel, Amit; Roulahamin, Nick; Kuiper, Jan H; Richardson, James B

2015-06-01

Metal-on-metal hip resurfacing is undertaken worldwide. This procedure helps preserve femoral bone stock and allows patients to return to high activity sports. Most outcome studies are individual surgeon case series from single centers where the results and outcomes are evaluated by the same surgeon. One method of increasing the external validity of a follow-up study is to have a multi-centre study design with independent assessment of the outcomes. We present an independent assessment of eleven year follow-up of hip resurfacing outcomes from an international hip resurfacing register. The purpose of this study was to assess: Implant survival at maximum follow-up for revision due to any reason, implant survival at maximum follow-up for revision due to major causes of failure, hip function following hip resurfacing and factors affecting hip function, effect of gender and age on hip function and implant survival, effect of femoral component size on hip function and implant survival. 4535 patients (5000 hips) entered into the registry during 1997-2002 were studied. In summary, at a maximum follow-up of 11 years hip resurfacing has a good implant survival of 96.2% and excellent post-operative function. This is excellent given the international and multisurgeon nature of this cohort where majority of the surgeons were in their learning curve.

Validation of Robotic Surgery Simulator (RoSS).

PubMed

Kesavadas, Thenkurussi; Stegemann, Andrew; Sathyaseelan, Gughan; Chowriappa, Ashirwad; Srimathveeravalli, Govindarajan; Seixas-Mikelus, Stéfanie; Chandrasekhar, Rameella; Wilding, Gregory; Guru, Khurshid

2011-01-01

Recent growth of daVinci Robotic Surgical System as a minimally invasive surgery tool has led to a call for better training of future surgeons. In this paper, a new virtual reality simulator, called RoSS is presented. Initial results from two studies - face and content validity, are very encouraging. 90% of the cohort of expert robotic surgeons felt that the simulator was excellent or somewhat close to the touch and feel of the daVinci console. Content validity of the simulator received 90% approval in some cases. These studies demonstrate that RoSS has the potential of becoming an important training tool for the daVinci surgical robot.

[Resources and risks in old age: the LUCAS-I marker set for a classification of elderly people as fit, pre-frail and frail. First results on validity from the Longitudinal Urban Cohort Ageing Study (LUCAS), Hamburg].

PubMed

Dapp, U; Anders, J; Golgert, S; von Renteln-Kruse, W; Minder, C E

2012-06-01

There is a need for a simple self-administered instrument to assess frailty in community-dwelling seniors. We present a new marker set to assess the functional state of seniors. Contrary to current literature, we focus not only on risks, but also include resources. The questions relate to facts (ways to do things), rather than on subjective information (e.g. exhaustion). It was developed in the context of the Longitudinal Urban Cohort Ageing Study (LUCAS) in Hamburg, Germany. The classification based on these questions proposes operational definitions of the terms fit, pre-frail and frail and is predictive for need for nursing care as well as mortality. A wealth of results establishes the validity of the categorisation compared to other health questions. One of the classification questions concerns cycling. For areas where cycling is not suitable, we propose to replace this question with one about independently walking 500 m. However, the cycling question appears to indicate frailty earlier. The self-administered questionnaire provides a simple, cost-effective way to screen seniors for early signs of declining function in order to start preventive action.

Development and validation of Prediction models for Risks of complications in Early-onset Pre-eclampsia (PREP): a prospective cohort study.

PubMed

Thangaratinam, Shakila; Allotey, John; Marlin, Nadine; Mol, Ben W; Von Dadelszen, Peter; Ganzevoort, Wessel; Akkermans, Joost; Ahmed, Asif; Daniels, Jane; Deeks, Jon; Ismail, Khaled; Barnard, Ann Marie; Dodds, Julie; Kerry, Sally; Moons, Carl; Riley, Richard D; Khan, Khalid S

2017-04-01

The prognosis of early-onset pre-eclampsia (before 34 weeks' gestation) is variable. Accurate prediction of complications is required to plan appropriate management in high-risk women. To develop and validate prediction models for outcomes in early-onset pre-eclampsia. Prospective cohort for model development, with validation in two external data sets. Model development: 53 obstetric units in the UK. Model transportability: PIERS (Pre-eclampsia Integrated Estimate of RiSk for mothers) and PETRA (Pre-Eclampsia TRial Amsterdam) studies. Pregnant women with early-onset pre-eclampsia. Nine hundred and forty-six women in the model development data set and 850 women (634 in PIERS, 216 in PETRA) in the transportability (external validation) data sets. The predictors were identified from systematic reviews of tests to predict complications in pre-eclampsia and were prioritised by Delphi survey. The primary outcome was the composite of adverse maternal outcomes established using Delphi surveys. The secondary outcome was the composite of fetal and neonatal complications. We developed two prediction models: a logistic regression model (PREP-L) to assess the overall risk of any maternal outcome until postnatal discharge and a survival analysis model (PREP-S) to obtain individual risk estimates at daily intervals from diagnosis until 34 weeks. Shrinkage was used to adjust for overoptimism of predictor effects. For internal validation (of the full models in the development data) and external validation (of the reduced models in the transportability data), we computed the ability of the models to discriminate between those with and without poor outcomes ( c -statistic), and the agreement between predicted and observed risk (calibration slope). The PREP-L model included maternal age, gestational age at diagnosis, medical history, systolic blood pressure, urine protein-to-creatinine ratio, platelet count, serum urea concentration, oxygen saturation, baseline treatment with

Evaluating the Validity of a Two-stage Sample in a Birth Cohort Established from Administrative Databases.

PubMed

El-Zein, Mariam; Conus, Florence; Benedetti, Andrea; Parent, Marie-Elise; Rousseau, Marie-Claude

2016-01-01

When using administrative databases for epidemiologic research, a subsample of subjects can be interviewed, eliciting information on undocumented confounders. This article presents a thorough investigation of the validity of a two-stage sample encompassing an assessment of nonparticipation and quantification of the extent of bias. Established through record linkage of administrative databases, the Québec Birth Cohort on Immunity and Health (n = 81,496) aims to study the association between Bacillus Calmette-Guérin vaccination and asthma. Among 76,623 subjects classified in four Bacillus Calmette-Guérin-asthma strata, a two-stage sampling strategy with a balanced design was used to randomly select individuals for interviews. We compared stratum-specific sociodemographic characteristics and healthcare utilization of stage 2 participants (n = 1,643) with those of eligible nonparticipants (n = 74,980) and nonrespondents (n = 3,157). We used logistic regression to determine whether participation varied across strata according to these characteristics. The effect of nonparticipation was described by the relative odds ratio (ROR = ORparticipants/ORsource population) for the association between sociodemographic characteristics and asthma. Parental age at childbirth, area of residence, family income, and healthcare utilization were comparable between groups. Participants were slightly more likely to be women and have a mother born in Québec. Participation did not vary across strata by sex, parental birthplace, or material and social deprivation. Estimates were not biased by nonparticipation; most RORs were below one and bias never exceeded 20%. Our analyses evaluate and provide a detailed demonstration of the validity of a two-stage sample for researchers assembling similar research infrastructures.

Real-time Raman spectroscopy for automatic in vivo skin cancer detection: an independent validation.

PubMed

Zhao, Jianhua; Lui, Harvey; Kalia, Sunil; Zeng, Haishan

2015-11-01

In a recent study, we have demonstrated that real-time Raman spectroscopy could be used for skin cancer diagnosis. As a translational study, the objective of this study is to validate previous findings through a completely independent clinical test. In total, 645 confirmed cases were included in the analysis, including a cohort of 518 cases from a previous study, and an independent cohort of 127 new cases. Multi-variant statistical data analyses including principal component with general discriminant analysis (PC-GDA) and partial least squares (PLS) were used separately for lesion classification, which generated similar results. When the previous cohort (n = 518) was used as training and the new cohort (n = 127) was used as testing, the area under the receiver operating characteristic curve (ROC AUC) was found to be 0.889 (95 % CI 0.834-0.944; PLS); when the two cohorts were combined, the ROC AUC was 0.894 (95 % CI 0.870-0.918; PLS) with the narrowest confidence intervals. Both analyses were comparable to the previous findings, where the ROC AUC was 0.896 (95 % CI 0.846-0.946; PLS). The independent study validates that real-time Raman spectroscopy could be used for automatic in vivo skin cancer diagnosis with good accuracy.

Does my patient have chronic Chagas disease? Development and temporal validation of a diagnostic risk score.

PubMed

Brasil, Pedro Emmanuel Alvarenga Americano do; Xavier, Sergio Salles; Holanda, Marcelo Teixeira; Hasslocher-Moreno, Alejandro Marcel; Braga, José Ueleres

2016-01-01

With the globalization of Chagas disease, unexperienced health care providers may have difficulties in identifying which patients should be examined for this condition. This study aimed to develop and validate a diagnostic clinical prediction model for chronic Chagas disease. This diagnostic cohort study included consecutive volunteers suspected to have chronic Chagas disease. The clinical information was blindly compared to serological tests results, and a logistic regression model was fit and validated. The development cohort included 602 patients, and the validation cohort included 138 patients. The Chagas disease prevalence was 19.9%. Sex, age, referral from blood bank, history of living in a rural area, recognizing the kissing bug, systemic hypertension, number of siblings with Chagas disease, number of relatives with a history of stroke, ECG with low voltage, anterosuperior divisional block, pathologic Q wave, right bundle branch block, and any kind of extrasystole were included in the final model. Calibration and discrimination in the development and validation cohorts (ROC AUC 0.904 and 0.912, respectively) were good. Sensitivity and specificity analyses showed that specificity reaches at least 95% above the predicted 43% risk, while sensitivity is at least 95% below the predicted 7% risk. Net benefit decision curves favor the model across all thresholds. A nomogram and an online calculator (available at http://shiny.ipec.fiocruz.br:3838/pedrobrasil/chronic_chagas_disease_prediction/) were developed to aid in individual risk estimation.

Validation of the Retinal Detachment after Open Globe Injury (RD-OGI) Score as an Effective Tool for Predicting Retinal Detachment.

PubMed

Brodowska, Katarzyna; Stryjewski, Tomasz P; Papavasileiou, Evangelia; Chee, Yewlin E; Eliott, Dean

2017-05-01

The Retinal Detachment after Open Globe Injury (RD-OGI) Score is a clinical prediction model that was developed at the Massachusetts Eye and Ear Infirmary to predict the risk of retinal detachment (RD) after open globe injury (OGI). This study sought to validate the RD-OGI Score in an independent cohort of patients. Retrospective cohort study. The predictive value of the RD-OGI Score was evaluated by comparing the original RD-OGI Scores of 893 eyes with OGI that presented between 1999 and 2011 (the derivation cohort) with 184 eyes with OGI that presented from January 1, 2012, to January 31, 2014 (the validation cohort). Three risk classes (low, moderate, and high) were created and logistic regression was undertaken to evaluate the optimal predictive value of the RD-OGI Score. A Kaplan-Meier survival analysis evaluated survival experience between the risk classes. Time to RD. At 1 year after OGI, 255 eyes (29%) in the derivation cohort and 66 eyes (36%) in the validation cohort were diagnosed with an RD. At 1 year, the low risk class (RD-OGI Scores 0-2) had a 3% detachment rate in the derivation cohort and a 0% detachment rate in the validation cohort, the moderate risk class (RD-OGI Scores 2.5-4.5) had a 29% detachment rate in the derivation cohort and a 35% detachment rate in the validation cohort, and the high risk class (RD-OGI scores 5-7.5) had a 73% detachment rate in the derivation cohort and an 86% detachment rate in the validation cohort. Regression modeling revealed the RD-OGI to be highly discriminative, especially 30 days after injury, with an area under the receiver operating characteristic curve of 0.939 in the validation cohort. Survival experience was significantly different depending upon the risk class (P < 0.0001, log-rank chi-square). The RD-OGI Score can reliably predict the future risk of developing an RD based on clinical variables that are present at the time of the initial evaluation after OGI. Copyright © 2017 American Academy of

Internal construct validity of the stress-energy questionnaire in a working population, a cohort study.

PubMed

Hadzibajramovic, Emina; Ahlborg, Gunnar; Grimby-Ekman, Anna; Lundgren-Nilsson, Åsa

2015-02-25

Psychosocial stress at work has been recognised as one of the most important factors behind the increase in sick leave due to stress-related mental disorders. It is therefore important to be able to measure perceived work stress in a way that is both valid and reliable. It has been suggested that the Stress-Energy Questionnaire (SEQ) could be a useful tool for measuring mood (stress and energy) at work and it has been used in many Scandinavian studies. The aim of the study is to examine the internal construct validity of the SEQ in a working population and to address measurement issues, such as the ordering of response categories and potential differences in how women and men use the scale - what is termed differential item functioning (DIF). The data used in the present study is baseline data from a longitudinal cohort study aimed at evaluating psychosocial working conditions, stress, health and well-being among employees in two human service organisations in Western Sweden. A modern psychometric approach for scale validations, the Rasch model, was used. Stress items showed a satisfactory fit to the model. Problems related to unidimensionality and local dependence were found when the six stress items were fitted to the model, but these could be resolved by using two testlets. As regards the energy scale, although the final analysis showed an acceptable fit to the model some scale problems were identified. The item dull had disordered thresholds and DIF for gender was detected for the item passive. The items were not well targeted to the persons, with skewness towards high energy. This might explain the scale problems that were detected but these problems need to be investigated in a group where the level of energy is spread across the trait, measured by the SEQ. The stress scale of the SEQ has good psychometric properties and provides a useful tool for assessing work-related stress, on both group and individual levels. However, the limitations of the energy scale

Derivation and External Validation of Prediction Models for Advanced Chronic Kidney Disease Following Acute Kidney Injury

PubMed Central

Pannu, Neesh; Hemmelgarn, Brenda R.; Austin, Peter C.; Tan, Zhi; McArthur, Eric; Manns, Braden J.; Tonelli, Marcello; Wald, Ron; Quinn, Robert R.; Ravani, Pietro; Garg, Amit X.

2017-01-01

Importance Some patients will develop chronic kidney disease after a hospitalization with acute kidney injury; however, no risk-prediction tools have been developed to identify high-risk patients requiring follow-up. Objective To derive and validate predictive models for progression of acute kidney injury to advanced chronic kidney disease. Design, Setting, and Participants Data from 2 population-based cohorts of patients with a prehospitalization estimated glomerular filtration rate (eGFR) of more than 45 mL/min/1.73 m2 and who had survived hospitalization with acute kidney injury (defined by a serum creatinine increase during hospitalization > 0.3 mg/dL or > 50% of their prehospitalization baseline), were used to derive and validate multivariable prediction models. The risk models were derived from 9973 patients hospitalized in Alberta, Canada (April 2004-March 2014, with follow-up to March 2015). The risk models were externally validated with data from a cohort of 2761 patients hospitalized in Ontario, Canada (June 2004-March 2012, with follow-up to March 2013). Exposures Demographic, laboratory, and comorbidity variables measured prior to discharge. Main Outcomes and Measures Advanced chronic kidney disease was defined by a sustained reduction in eGFR less than 30 mL/min/1.73 m2 for at least 3 months during the year after discharge. All participants were followed up for up to 1 year. Results The participants (mean [SD] age, 66 [15] years in the derivation and internal validation cohorts and 69 [11] years in the external validation cohort; 40%-43% women per cohort) had a mean (SD) baseline serum creatinine level of 1.0 (0.2) mg/dL and more than 20% had stage 2 or 3 acute kidney injury. Advanced chronic kidney disease developed in 408 (2.7%) of 9973 patients in the derivation cohort and 62 (2.2%) of 2761 patients in the external validation cohort. In the derivation cohort, 6 variables were independently associated with the outcome: older age, female sex, higher

Risk Prediction Models of Locoregional Failure After Radical Cystectomy for Urothelial Carcinoma: External Validation in a Cohort of Korean Patients

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

Ku, Ja Hyeon; Kim, Myong; Jeong, Chang Wook

2014-08-01

Purpose: To evaluate the predictive accuracy and general applicability of the locoregional failure model in a different cohort of patients treated with radical cystectomy. Methods and Materials: A total of 398 patients were included in the analysis. Death and isolated distant metastasis were considered competing events, and patients without any events were censored at the time of last follow-up. The model included the 3 variables pT classification, the number of lymph nodes identified, and margin status, as follows: low risk (≤pT2), intermediate risk (≥pT3 with ≥10 nodes removed and negative margins), and high risk (≥pT3 with <10 nodes removed ormore » positive margins). Results: The bootstrap-corrected concordance index of the model 5 years after radical cystectomy was 66.2%. When the risk stratification was applied to the validation cohort, the 5-year locoregional failure estimates were 8.3%, 21.2%, and 46.3% for the low-risk, intermediate-risk, and high-risk groups, respectively. The risk of locoregional failure differed significantly between the low-risk and intermediate-risk groups (subhazard ratio [SHR], 2.63; 95% confidence interval [CI], 1.35-5.11; P<.001) and between the low-risk and high-risk groups (SHR, 4.28; 95% CI, 2.17-8.45; P<.001). Although decision curves were appropriately affected by the incidence of the competing risk, decisions about the value of the models are not likely to be affected because the model remains of value over a wide range of threshold probabilities. Conclusions: The model is not completely accurate, but it demonstrates a modest level of discrimination, adequate calibration, and meaningful net benefit gain for prediction of locoregional failure after radical cystectomy.« less

Lessons Learned from a Cross-Model Validation between a Discrete Event Simulation Model and a Cohort State-Transition Model for Personalized Breast Cancer Treatment.

PubMed

Jahn, Beate; Rochau, Ursula; Kurzthaler, Christina; Paulden, Mike; Kluibenschädl, Martina; Arvandi, Marjan; Kühne, Felicitas; Goehler, Alexander; Krahn, Murray D; Siebert, Uwe

2016-04-01

Breast cancer is the most common malignancy among women in developed countries. We developed a model (the Oncotyrol breast cancer outcomes model) to evaluate the cost-effectiveness of a 21-gene assay when used in combination with Adjuvant! Online to support personalized decisions about the use of adjuvant chemotherapy. The goal of this study was to perform a cross-model validation. The Oncotyrol model evaluates the 21-gene assay by simulating a hypothetical cohort of 50-year-old women over a lifetime horizon using discrete event simulation. Primary model outcomes were life-years, quality-adjusted life-years (QALYs), costs, and incremental cost-effectiveness ratios (ICERs). We followed the International Society for Pharmacoeconomics and Outcomes Research-Society for Medical Decision Making (ISPOR-SMDM) best practice recommendations for validation and compared modeling results of the Oncotyrol model with the state-transition model developed by the Toronto Health Economics and Technology Assessment (THETA) Collaborative. Both models were populated with Canadian THETA model parameters, and outputs were compared. The differences between the models varied among the different validation end points. The smallest relative differences were in costs, and the greatest were in QALYs. All relative differences were less than 1.2%. The cost-effectiveness plane showed that small differences in the model structure can lead to different sets of nondominated test-treatment strategies with different efficiency frontiers. We faced several challenges: distinguishing between differences in outcomes due to different modeling techniques and initial coding errors, defining meaningful differences, and selecting measures and statistics for comparison (means, distributions, multivariate outcomes). Cross-model validation was crucial to identify and correct coding errors and to explain differences in model outcomes. In our comparison, small differences in either QALYs or costs led to changes in

Prognostic Validation of SKY92 and Its Combination With ISS in an Independent Cohort of Patients With Multiple Myeloma.

PubMed

van Beers, Erik H; van Vliet, Martin H; Kuiper, Rowan; de Best, Leonie; Anderson, Kenneth C; Chari, Ajai; Jagannath, Sundar; Jakubowiak, Andrzej; Kumar, Shaji K; Levy, Joan B; Auclair, Daniel; Lonial, Sagar; Reece, Donna; Richardson, Paul; Siegel, David S; Stewart, A Keith; Trudel, Suzanne; Vij, Ravi; Zimmerman, Todd M; Fonseca, Rafael

2017-09-01

High risk and low risk multiple myeloma patients follow a very different clinical course as reflected in their PFS and OS. To be clinically useful, methodologies used to identify high and low risk disease must be validated in representative independent clinical data and available so that patients can be managed appropriately. A recent analysis has indicated that SKY92 combined with the International Staging System (ISS) identifies patients with different risk disease with high sensitivity. Here we computed the performance of eight gene expression based classifiers SKY92, UAMS70, UAMS80, IFM15, Proliferation Index, Centrosome Index, Cancer Testis Antigen and HM19 as well as the combination of SKY92/ISS in an independent cohort of 91 newly diagnosed MM patients. The classifiers identified between 9%-21% of patients as high risk, with hazard ratios (HRs) between 1.9 and 8.2. Among the eight signatures, SKY92 identified the largest proportion of patients (21%) also with the highest HR (8.2). Our analysis also validated the combination SKY92/ISS for identification of three classes; low risk (42%), intermediate risk (37%) and high risk (21%). Between low risk and high risk classes the HR is >10. Copyright © 2017 Elsevier Inc. All rights reserved.

The DASS-14: Improving the Construct Validity and Reliability of the Depression, Anxiety, and Stress Scale in a Cohort of Health Professionals.

PubMed

Wise, Frances M; Harris, Darren W; Olver, John H

2017-01-01

Considerable research has been undertaken in evaluating the DASS-21 in a variety of clinical populations, but studies of the instrument's psychometric adequacy in healthcare professionals is lacking. This study aimed to establish and improve the construct validity and reliability of the DASS-21 in a cohort of Australian health professionals. 343 rehabilitation health professionals completed the DASS-21, along with a demographic questionnaire. Principal components analysis was performed to identify potential factors in the DASS-21. Factors were interpreted against theoretical constructs underlying the instrument. Items loading on separate factors were then subjected to reliability analysis to determine internal consistency of subscales. Items that demonstrated poor fit, or loaded onto more than one factor, were deleted to maximise the reliability of each subscale. Principal components analysis identified three dimensions (depression, anxiety, stress) in a modified version of the DASS-21 (renamed DASS-14), with appropriate construct validity and good reliability (a=0.73 to 0.88). The three dimensions accounted for over 62% of variance between items. The modified DASS-14 scale is a more parsimonious measure of depression, anxiety, and stress, with acceptable reliability and construct validity, in rehabilitation health professionals and is appropriate for use in studies of similar populations.

Ruling out coronary artery disease in primary care: development and validation of a simple prediction rule.

PubMed

Bösner, Stefan; Haasenritter, Jörg; Becker, Annette; Karatolios, Konstantinos; Vaucher, Paul; Gencer, Baris; Herzig, Lilli; Heinzel-Gutenbrunner, Monika; Schaefer, Juergen R; Abu Hani, Maren; Keller, Heidi; Sönnichsen, Andreas C; Baum, Erika; Donner-Banzhoff, Norbert

2010-09-07

Chest pain can be caused by various conditions, with life-threatening cardiac disease being of greatest concern. Prediction scores to rule out coronary artery disease have been developed for use in emergency settings. We developed and validated a simple prediction rule for use in primary care. We conducted a cross-sectional diagnostic study in 74 primary care practices in Germany. Primary care physicians recruited all consecutive patients who presented with chest pain (n = 1249) and recorded symptoms and findings for each patient (derivation cohort). An independent expert panel reviewed follow-up data obtained at six weeks and six months on symptoms, investigations, hospital admissions and medications to determine the presence or absence of coronary artery disease. Adjusted odds ratios of relevant variables were used to develop a prediction rule. We calculated measures of diagnostic accuracy for different cut-off values for the prediction scores using data derived from another prospective primary care study (validation cohort). The prediction rule contained five determinants (age/sex, known vascular disease, patient assumes pain is of cardiac origin, pain is worse during exercise, and pain is not reproducible by palpation), with the score ranging from 0 to 5 points. The area under the curve (receiver operating characteristic curve) was 0.87 (95% confidence interval [CI] 0.83-0.91) for the derivation cohort and 0.90 (95% CI 0.87-0.93) for the validation cohort. The best overall discrimination was with a cut-off value of 3 (positive result 3-5 points; negative result validation cohort. It can help to rule out coronary artery disease in patients presenting with chest pain in primary care.

Validation of the Framingham general cardiovascular risk score in a multiethnic Asian population: a retrospective cohort study

PubMed Central

Gray, Sarah Yu Weng; Ching, Siew Mooi; Lim, Hooi Min; Chinna, Karuthan

2015-01-01

Objective This study aims to examine the validity of the Framingham general cardiovascular disease (CVD) risk chart in a primary care setting. Design This is a 10-year retrospective cohort study. Setting A primary care clinic in a teaching hospital in Malaysia. Participants 967 patients’ records were randomly selected from patients who were attending follow-up in the clinic. Main outcome measures Baseline demographic data, history of diabetes and smoking, blood pressure (BP), and serum lipids were captured from patient records in 1998. Each patient's Framingham CVD score was computed from these parameters. All atherosclerotic CVD events occurring between 1998 and 2007 were counted. Results In 1998, mean age was 57 years with 33.8% men, 6.1% smokers, 43.3% diabetics and 59.7% hypertensive. Median BP was 140/80 mm Hg and total cholesterol 6.0 mmol/L (1.3). The predicted median Framingham general CVD risk score for the study population was 21.5% (IQR 1.2–30.0) while the actual CVD events that occurred in the 10 years was 13.1% (127/967). The median CVD points for men was 30.0, giving them a CVD risk of more than 30%; for women it is 18.5, a CVD risk of 21.5%. Our study found that the Framingham general CVD risk score to have moderate discrimination with an area under the receiver operating characteristic curve (AUC) of 0.63. It also discriminates well for Malay (AUC 0.65, p=0.01), Chinese (AUC 0.60, p=0.03), and Indians (AUC 0.65, p=0.001). There was good calibration with Hosmer-Lemeshow test χ2=3.25, p=0.78. Conclusions Taking into account that this cohort of patients were already on treatment, the Framingham General CVD Risk Prediction Score predicts fairly accurately for men and overestimates somewhat for women. In the absence of local risk prediction charts, the Framingham general CVD risk prediction chart is a reasonable alternative for use in a multiethnic group in a primary care setting. PMID:25991451

Leveraging biospecimen resources for discovery or validation of markers for early cancer detection.

PubMed

Schully, Sheri D; Carrick, Danielle M; Mechanic, Leah E; Srivastava, Sudhir; Anderson, Garnet L; Baron, John A; Berg, Christine D; Cullen, Jennifer; Diamandis, Eleftherios P; Doria-Rose, V Paul; Goddard, Katrina A B; Hankinson, Susan E; Kushi, Lawrence H; Larson, Eric B; McShane, Lisa M; Schilsky, Richard L; Shak, Steven; Skates, Steven J; Urban, Nicole; Kramer, Barnett S; Khoury, Muin J; Ransohoff, David F

2015-04-01

Validation of early detection cancer biomarkers has proven to be disappointing when initial promising claims have often not been reproducible in diagnostic samples or did not extend to prediagnostic samples. The previously reported lack of rigorous internal validity (systematic differences between compared groups) and external validity (lack of generalizability beyond compared groups) may be effectively addressed by utilizing blood specimens and data collected within well-conducted cohort studies. Cohort studies with prediagnostic specimens (eg, blood specimens collected prior to development of clinical symptoms) and clinical data have recently been used to assess the validity of some early detection biomarkers. With this background, the Division of Cancer Control and Population Sciences (DCCPS) and the Division of Cancer Prevention (DCP) of the National Cancer Institute (NCI) held a joint workshop in August 2013. The goal was to advance early detection cancer research by considering how the infrastructure of cohort studies that already exist or are being developed might be leveraged to include appropriate blood specimens, including prediagnostic specimens, ideally collected at periodic intervals, along with clinical data about symptom status and cancer diagnosis. Three overarching recommendations emerged from the discussions: 1) facilitate sharing of existing specimens and data, 2) encourage collaboration among scientists developing biomarkers and those conducting observational cohort studies or managing healthcare systems with cohorts followed over time, and 3) conduct pilot projects that identify and address key logistic and feasibility issues regarding how appropriate specimens and clinical data might be collected at reasonable effort and cost within existing or future cohorts. © Published by Oxford University Press 2015.

Leveraging Biospecimen Resources for Discovery or Validation of Markers for Early Cancer Detection

PubMed Central

Carrick, Danielle M.; Mechanic, Leah E.; Srivastava, Sudhir; Anderson, Garnet L.; Baron, John A.; Berg, Christine D.; Cullen, Jennifer; Diamandis, Eleftherios P.; Doria-Rose, V. Paul; Goddard, Katrina A. B.; Hankinson, Susan E.; Kushi, Lawrence H.; Larson, Eric B.; McShane, Lisa M.; Schilsky, Richard L.; Shak, Steven; Skates, Steven J.; Urban, Nicole; Kramer, Barnett S.; Khoury, Muin J.; Ransohoff, David F.

2015-01-01

Validation of early detection cancer biomarkers has proven to be disappointing when initial promising claims have often not been reproducible in diagnostic samples or did not extend to prediagnostic samples. The previously reported lack of rigorous internal validity (systematic differences between compared groups) and external validity (lack of generalizability beyond compared groups) may be effectively addressed by utilizing blood specimens and data collected within well-conducted cohort studies. Cohort studies with prediagnostic specimens (eg, blood specimens collected prior to development of clinical symptoms) and clinical data have recently been used to assess the validity of some early detection biomarkers. With this background, the Division of Cancer Control and Population Sciences (DCCPS) and the Division of Cancer Prevention (DCP) of the National Cancer Institute (NCI) held a joint workshop in August 2013. The goal was to advance early detection cancer research by considering how the infrastructure of cohort studies that already exist or are being developed might be leveraged to include appropriate blood specimens, including prediagnostic specimens, ideally collected at periodic intervals, along with clinical data about symptom status and cancer diagnosis. Three overarching recommendations emerged from the discussions: 1) facilitate sharing of existing specimens and data, 2) encourage collaboration among scientists developing biomarkers and those conducting observational cohort studies or managing healthcare systems with cohorts followed over time, and 3) conduct pilot projects that identify and address key logistic and feasibility issues regarding how appropriate specimens and clinical data might be collected at reasonable effort and cost within existing or future cohorts. PMID:25688116

Development and validation of immune dysfunction score to predict 28-day mortality of sepsis patients

PubMed Central

Fang, Wen-Feng; Douglas, Ivor S.; Chen, Yu-Mu; Lin, Chiung-Yu; Kao, Hsu-Ching; Fang, Ying-Tang; Huang, Chi-Han; Chang, Ya-Ting; Huang, Kuo-Tung; Wang, Yi-His; Wang, Chin-Chou

2017-01-01

Background Sepsis-induced immune dysfunction ranging from cytokines storm to immunoparalysis impacts outcomes. Monitoring immune dysfunction enables better risk stratification and mortality prediction and is mandatory before widely application of immunoadjuvant therapies. We aimed to develop and validate a scoring system according to patients’ immune dysfunction status for 28-day mortality prediction. Methods A prospective observational study from a cohort of adult sepsis patients admitted to ICU between August 2013 and June 2016 at Kaohsiung Chang Gung Memorial Hospital in Taiwan. We evaluated immune dysfunction status through measurement of baseline plasma Cytokine levels, Monocyte human leukocyte-DR expression by flow cytometry, and stimulated immune response using post LPS stimulated cytokine elevation ratio. An immune dysfunction score was created for 28-day mortality prediction and was validated. Results A total of 151 patients were enrolled. Data of the first consecutive 106 septic patients comprised the training cohort, and of other 45 patients comprised the validation cohort. Among the 106 patients, 21 died and 85 were still alive on day 28 after ICU admission. (mortality rate, 19.8%). Independent predictive factors revealed via multivariate logistic regression analysis included segmented neutrophil-to-monocyte ratio, granulocyte-colony stimulating factor, interleukin-10, and monocyte human leukocyte antigen-antigen D–related levels, all of which were selected to construct the score, which predicted 28-day mortality with area under the curve of 0.853 and 0.789 in the training and validation cohorts, respectively. Conclusions The immune dysfunction scoring system developed here included plasma granulocyte-colony stimulating factor level, interleukin-10 level, serum segmented neutrophil-to-monocyte ratio, and monocyte human leukocyte antigen-antigen D–related expression appears valid and reproducible for predicting 28-day mortality. PMID:29073262

Validation of nomograms for overall survival, cancer-specific survival, and recurrence in carcinoma of the major salivary glands.

PubMed

Hay, Ashley; Migliacci, Jocelyn; Zanoni, Daniella Karassawa; Patel, Snehal; Yu, Changhong; Kattan, Michael W; Ganly, Ian

2018-05-01

The purpose of this study was to investigate the performance of the Memorial Sloan Kettering Cancer Center salivary carcinoma nomograms predicting overall survival, cancer-specific survival, and recurrence with an external validation dataset. The validation dataset comprised 123 patients treated between 2010 and 2015 at our institution. They were evaluated by assessing discrimination (concordance index [C-index]) and calibration (plotting predicted vs actual probabilities for quintiles). The validation cohort (n = 123) showed some differences to the original cohort (n = 301). The validation cohort had less high-grade cancers (P = .006), less lymphovascular invasion (LVI; P < .001) and shorter follow-up of 19 months versus 45.6 months. Validation showed a C-index of 0.833 (95% confidence interval [CI] 0.758-0.908), 0.807 (95% CI 0.717-0.898), and 0.844 (95% CI 0.768-0.920) for overall survival, cancer-specific survival, and recurrence, respectively. The 3 salivary gland nomograms performed well using a contemporary validation dataset, despite limitations related to sample size, follow-up, and differences in clinical and pathology characteristics between the original and validation cohorts. © 2018 Wiley Periodicals, Inc.

Examinee Noneffort and the Validity of Program Assessment Results

ERIC Educational Resources Information Center

Wise, Steven L.; DeMars, Christine E.

2010-01-01

Educational program assessment studies often use data from low-stakes tests to provide evidence of program quality. The validity of scores from such tests, however, is potentially threatened by examinee noneffort. This study investigated the extent to which one type of noneffort--rapid-guessing behavior--distorted the results from three types of…

Validation of a patient-level medication regimen complexity index as a possible tool to identify patients for medication therapy management intervention.

PubMed

Hirsch, Jan D; Metz, Kelli R; Hosokawa, Patrick W; Libby, Anne M

2014-08-01

(all cohorts 0.08 and 0.06, respectively) supported MRCI divergent validity. This study used cross-sectional, retrospective patient data for a small number of patients and clinical pharmacists from only two universities; therefore, results may have limited generalizability. The patient-level MRCI is a valid tool for assessing medication regimen complexity that can be applied by using data commonly found in claims and EMR databases and could be useful to identify patients who may benefit from medication therapy management. © 2014 The Authors Pharmacotherapy published by Wiley Periodicals, Inc. on behalf of Pharmacotherapy Publications, Inc.

Over-reported peripheral neuropathy symptoms in a cohort of HIV infected and uninfected Rwandan women: the need for validated locally appropriate questionnaires.

PubMed

Tumusiime, David K; Musabeyezu, Emmanuel; Mutimurah, Eugene; Hoover, Donald R; Shi, Qiuhu; Rudakemwa, Emmanuel; Ndacyayisenga, Victorien; Dusingize, Jean Claude; Sinayobye, Jean D'Amour; Stewart, Aimee; Venter, Francois W D; Anastos, Kathryn

2014-06-01

Peripheral neuropathy symptoms (PNS) are commonly manifested in HIV-infected (HIV+) individuals, although data are limited on the prevalence and predictors of PNS in HIV+ patients from sub-Saharan Africa. To determine the prevalence and predictors of PNS in HIV+ and HIV-uninfected (HIV-) Rwandan women. Data were analysed from 936 (710 HIV+ and 226 HIV-) women from the Rwanda Women Interassociation Study and Assessment (RWISA), an observational prospective cohort study investigating the effectiveness and toxicity of ART in HIV+ women. Of 936 enrolled, 920 (98.3%) were included in this analysis with 44% of HIV- and 52% of the HIV+ women reporting PNS (p=0.06). CD4+ count was not associated with PNS, although there was a non-significant trend towards higher prevalence in those with lower CD4+ counts. For the HIV- women, only alcohol and co-trimoxazole use were independently associated with PNS. WHO HIV stage IV illness and albumin ≤ 3.5 were associated with PNS in HIV+ women. The rate of peripheral neuropathy symptoms reported in this cohort of HIV-infected African women seems implausible, and rather suggests that the screening tool for peripheral neuropathy in culturally diverse African settings be locally validated.

Validation Test Results for Orthogonal Probe Eddy Current Thruster Inspection System

NASA Technical Reports Server (NTRS)

Wincheski, Russell A.

2007-01-01

Recent nondestructive evaluation efforts within NASA have focused on an inspection system for the detection of intergranular cracking originating in the relief radius of Primary Reaction Control System (PCRS) Thrusters. Of particular concern is deep cracking in this area which could lead to combustion leakage in the event of through wall cracking from the relief radius into an acoustic cavity of the combustion chamber. In order to reliably detect such defects while ensuring minimal false positives during inspection, the Orthogonal Probe Eddy Current (OPEC) system has been developed and an extensive validation study performed. This report describes the validation procedure, sample set, and inspection results as well as comparing validation flaws with the response from naturally occuring damage.

Ride qualities criteria validation/pilot performance study: Flight test results

NASA Technical Reports Server (NTRS)

Nardi, L. U.; Kawana, H. Y.; Greek, D. C.

1979-01-01

Pilot performance during a terrain following flight was studied for ride quality criteria validation. Data from manual and automatic terrain following operations conducted during low level penetrations were analyzed to determine the effect of ride qualities on crew performance. The conditions analyzed included varying levels of turbulence, terrain roughness, and mission duration with a ride smoothing system on and off. Limited validation of the B-1 ride quality criteria and some of the first order interactions between ride qualities and pilot/vehicle performance are highlighted. An earlier B-1 flight simulation program correlated well with the flight test results.

Validation of a Simple Score to Determine Risk of Early Rejection After Pediatric Heart Transplantation.

PubMed

Butts, Ryan J; Savage, Andrew J; Atz, Andrew M; Heal, Elisabeth M; Burnette, Ali L; Kavarana, Minoo M; Bradley, Scott M; Chowdhury, Shahryar M

2015-09-01

This study aimed to develop a reliable and feasible score to assess the risk of rejection in pediatric heart transplantation recipients during the first post-transplant year. The first post-transplant year is the most likely time for rejection to occur in pediatric heart transplantation. Rejection during this period is associated with worse outcomes. The United Network for Organ Sharing database was queried for pediatric patients (age <18 years) who underwent isolated orthotopic heart transplantation from January 1, 2000 to December 31, 2012. Transplantations were divided into a derivation cohort (n = 2,686) and a validation (n = 509) cohort. The validation cohort was randomly selected from 20% of transplantations from 2005 to 2012. Covariates found to be associated with rejection (p < 0.2) were included in the initial multivariable logistic regression model. The final model was derived by including only variables independently associated with rejection. A risk score was then developed using relative magnitudes of the covariates' odds ratio. The score was then tested in the validation cohort. A 9-point risk score using 3 variables (age, cardiac diagnosis, and panel reactive antibody) was developed. Mean score in the derivation and validation cohorts were 4.5 ± 2.6 and 4.8 ± 2.7, respectively. A higher score was associated with an increased rate of rejection (score = 0, 10.6% in the validation cohort vs. score = 9, 40%; p < 0.01). In weighted regression analysis, the model-predicted risk of rejection correlated closely with the actual rates of rejection in the validation cohort (R(2) = 0.86; p < 0.01). The rejection score is accurate in determining the risk of early rejection in pediatric heart transplantation recipients. The score has the potential to be used in clinical practice to aid in determining the immunosuppressant regimen and the frequency of rejection surveillance in the first post-transplant year. Copyright © 2015 American College of Cardiology

Development and validation of a prediction model for functional decline in older medical inpatients.

PubMed

Takada, Toshihiko; Fukuma, Shingo; Yamamoto, Yosuke; Tsugihashi, Yukio; Nagano, Hiroyuki; Hayashi, Michio; Miyashita, Jun; Azuma, Teruhisa; Fukuhara, Shunichi

2018-05-17

To prevent functional decline in older inpatients, identification of high-risk patients is crucial. The aim of this study was to develop and validate a prediction model to assess the risk of functional decline in older medical inpatients. In this retrospective cohort study, patients ≥65 years admitted acutely to medical wards were included. The healthcare database of 246 acute care hospitals (n = 229,913) was used for derivation, and two acute care hospitals (n = 1767 and 5443, respectively) were used for validation. Data were collected using a national administrative claims and discharge database. Functional decline was defined as a decline of the Katz score at discharge compared with on admission. About 6% of patients in the derivation cohort and 9% and 2% in each validation cohort developed functional decline. A model with 7 items, age, body mass index, living in a nursing home, ambulance use, need for assistance in walking, dementia, and bedsore, was developed. On internal validation, it demonstrated a c-statistic of 0.77 (95% confidence interval (CI) = 0.767-0.771) and good fit on the calibration plot. On external validation, the c-statistics were 0.79 (95% CI = 0.77-0.81) and 0.75 (95% CI = 0.73-0.77) for each cohort, respectively. Calibration plots showed good fit in one cohort and overestimation in the other one. A prediction model for functional decline in older medical inpatients was derived and validated. It is expected that use of the model would lead to early identification of high-risk patients and introducing early intervention. Copyright © 2018 Elsevier B.V. All rights reserved.

Person mobility in the design and analysis of cluster-randomized cohort prevention trials.

PubMed

Vuchinich, Sam; Flay, Brian R; Aber, Lawrence; Bickman, Leonard

2012-06-01

Person mobility is an inescapable fact of life for most cluster-randomized (e.g., schools, hospitals, clinic, cities, state) cohort prevention trials. Mobility rates are an important substantive consideration in estimating the effects of an intervention. In cluster-randomized trials, mobility rates are often correlated with ethnicity, poverty and other variables associated with disparity. This raises the possibility that estimated intervention effects may generalize to only the least mobile segments of a population and, thus, create a threat to external validity. Such mobility can also create threats to the internal validity of conclusions from randomized trials. Researchers must decide how to deal with persons who leave study clusters during a trial (dropouts), persons and clusters that do not comply with an assigned intervention, and persons who enter clusters during a trial (late entrants), in addition to the persons who remain for the duration of a trial (stayers). Statistical techniques alone cannot solve the key issues of internal and external validity raised by the phenomenon of person mobility. This commentary presents a systematic, Campbellian-type analysis of person mobility in cluster-randomized cohort prevention trials. It describes four approaches for dealing with dropouts, late entrants and stayers with respect to data collection, analysis and generalizability. The questions at issue are: 1) From whom should data be collected at each wave of data collection? 2) Which cases should be included in the analyses of an intervention effect? and 3) To what populations can trial results be generalized? The conclusions lead to recommendations for the design and analysis of future cluster-randomized cohort prevention trials.

Risk factors and nomogram for pancreatic pseudocysts in chronic pancreatitis: A cohort of 1998 patients.

PubMed

Hao, Lu; Pan, Jun; Wang, Dan; Bi, Ya-Wei; Ji, Jun-Tao; Xin, Lei; Liao, Zhuan; Du, Ting-Ting; Lin, Jin-Huan; Zhang, Di; Zeng, Xiang-Peng; Ye, Bo; Zou, Wen-Bin; Chen, Hui; Xie, Ting; Li, Bai-Rong; Zheng, Zhao-Hong; Hu, Liang-Hao; Li, Zhao-Shen

2017-07-01

Pancreatic pseudocyst is a common complication of chronic pancreatitis. The identification of risk factors and development of a nomogram for pancreatic pseudocysts in chronic pancreatitis patients may contribute to the early diagnosis and intervention of pancreatic pseudocysts. Patients with chronic pancreatitis admitted to our center from January 2000 to December 2013 were enrolled. Cumulative rates of pancreatic pseudocysts after the onset of chronic pancreatitis and after the diagnosis of chronic pancreatitis were calculated. Patients were randomly assigned, in a 2:1 ratio, to the training and validation cohort. Based on the training cohort, risk factors were identified through Cox proportional hazards regression model, and nomogram was developed. Internal and external validations were performed based on the training and validation cohort, respectively. With a total of 1998 patients, pancreatic pseudocysts were detected in 228 (11.41%) patients. Age at the onset of chronic pancreatitis, smoking, and severe acute pancreatitis were identified risk factors for pancreatic pseudocysts development while steatorrhea and pancreatic stones were protective factors. Incorporating these five factors, the nomogram achieved good concordance indexes of 0.735 and 0.628 in the training and validation cohorts, respectively, with well-fitted calibration curves. The nomogram achieved an individualized prediction of pancreatic pseudocysts development in chronic pancreatitis. It may help the early diagnosis and management of pancreatic pseudocysts. © 2017 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Time trends in cigarette smoking in two German cohorts--results from EPIC Germany.

PubMed

Rohrmann, S; Kroke, A; Boeing, H; Becker, N

2003-08-01

Smoking prevention is less advanced in Germany compared with other European and North American countries, and fewer data exist, especially on the consumption habits at the individual level over time. EPIC Germany, which is part of a European multicentre study on diet and cancer, collected data on individual smoking behaviour and allows for consideration of the changing consumption pattern for both centres and different age groups. Within EPIC 25 546 and 27 548 participants, respectively, were recruited in Heidelberg and Potsdam. Data on smoking habits were collected by means of a computer-guided interview during the baseline examination between 1994 and 1998. For each birth cohort smoking prevalence and mean number of cigarettes smoked per day at different ages were calculated. Additionally, the prevalence of non-filter cigarette smoking was computed. Smoking prevalence in the 1990s was still higher among men (Heidelberg 16.3-32.3%; Potsdam 18.2-29.3%) than among women (Heidelberg 12.8-32.0%; Potsdam 10.4-27.8%). However, the percentage of women smokers was still increasing. Filter cigarettes comprised a growing percentage of the cigarettes smoked, but especially among men differences between both German cohorts can still be seen: depending on age, 10.0-12.7% of men in the Heidelberg cohort smoked non-filter cigarettes, but only 1.1-2.3% in the Potsdam cohort. The quantity smoked was higher in the Heidelberg than in the Potsdam cohort with respect to the mean number of cigarettes smoked per day as well as the pack-years of smoking. In conclusion, smoking habits in the Potsdam and the Heidelberg cohorts did not strongly differ by smoking prevalence. However, they did differ according to the quantity and quality of smoking. These differences, as well as the changes over the last 40 years may contribute to a changing pattern of diseases in different groups of the German population.

Cigarette smoking and the risk of adult leukemia: results from the Three Mile Island cohort study.

PubMed

Xu, Xiaohui; Talbott, Evelyn O; Zborowski, Jeanne V; Rager, Judith R

2007-01-01

Smoking is an unconfirmed risk factor for the development of leukemia. The authors examined the potential link using data from the Three Mile Island cohort for the period 1979-1995. Eligible for analysis were 24,539 individuals aged 14 years or older who were followed up over 16 years from the Three Mile Island cohort. The authors identified all incident leukemia cases through the Pennsylvania Department of Health Cancer Registry. They used the Cox proportional hazards model to evaluate the relationships and observed 42 incident leukemia cases, including 15 acute myeloid leukemia (AML) cases, in the cohort. After controlling for other confounding factors, the authors found current smoking to be associated with an increased risk of adult AML (relative risk = 3.47; 95% confidence interval = 1.002-11.99). The authors also observed a marginally significant linear trend of risk of AML associated with the number of years smoked (p = .06). The results from this study suggested that cigarette smoking was associated with an increased risk of adult AML. Further investigation is required to confirm these findings.

Identification and validation of distinct biological phenotypes in patients with acute respiratory distress syndrome by cluster analysis.

PubMed

Bos, L D; Schouten, L R; van Vught, L A; Wiewel, M A; Ong, D S Y; Cremer, O; Artigas, A; Martin-Loeches, I; Hoogendijk, A J; van der Poll, T; Horn, J; Juffermans, N; Calfee, C S; Schultz, M J

2017-10-01

We hypothesised that patients with acute respiratory distress syndrome (ARDS) can be clustered based on concentrations of plasma biomarkers and that the thereby identified biological phenotypes are associated with mortality. Consecutive patients with ARDS were included in this prospective observational cohort study. Cluster analysis of 20 biomarkers of inflammation, coagulation and endothelial activation provided the phenotypes in a training cohort, not taking any outcome data into account. Logistic regression with backward selection was used to select the most predictive biomarkers, and these predicted phenotypes were validated in a separate cohort. Multivariable logistic regression was used to quantify the independent association with mortality. Two phenotypes were identified in 454 patients, which we named 'uninflamed' (N=218) and 'reactive' (N=236). A selection of four biomarkers (interleukin-6, interferon gamma, angiopoietin 1/2 and plasminogen activator inhibitor-1) could be used to accurately predict the phenotype in the training cohort (area under the receiver operating characteristics curve: 0.98, 95% CI 0.97 to 0.99). Mortality rates were 15.6% and 36.4% (p<0.001) in the training cohort and 13.6% and 37.5% (p<0.001) in the validation cohort (N=207). The 'reactive phenotype' was independent from confounders associated with intensive care unit mortality (training cohort: OR 1.13, 95% CI 1.04 to 1.23; validation cohort: OR 1.18, 95% CI 1.06 to 1.31). Patients with ARDS can be clustered into two biological phenotypes, with different mortality rates. Four biomarkers can be used to predict the phenotype with high accuracy. The phenotypes were very similar to those found in cohorts derived from randomised controlled trials, and these results may improve patient selection for future clinical trials targeting host response in patients with ARDS. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please

Acute Kidney Injury Risk Prediction in Patients Undergoing Coronary Angiography in a National Veterans Health Administration Cohort With External Validation.

PubMed

Brown, Jeremiah R; MacKenzie, Todd A; Maddox, Thomas M; Fly, James; Tsai, Thomas T; Plomondon, Mary E; Nielson, Christopher D; Siew, Edward D; Resnic, Frederic S; Baker, Clifton R; Rumsfeld, John S; Matheny, Michael E

2015-12-11

Acute kidney injury (AKI) occurs frequently after cardiac catheterization and percutaneous coronary intervention. Although a clinical risk model exists for percutaneous coronary intervention, no models exist for both procedures, nor do existing models account for risk factors prior to the index admission. We aimed to develop such a model for use in prospective automated surveillance programs in the Veterans Health Administration. We collected data on all patients undergoing cardiac catheterization or percutaneous coronary intervention in the Veterans Health Administration from January 01, 2009 to September 30, 2013, excluding patients with chronic dialysis, end-stage renal disease, renal transplant, and missing pre- and postprocedural creatinine measurement. We used 4 AKI definitions in model development and included risk factors from up to 1 year prior to the procedure and at presentation. We developed our prediction models for postprocedural AKI using the least absolute shrinkage and selection operator (LASSO) and internally validated using bootstrapping. We developed models using 115 633 angiogram procedures and externally validated using 27 905 procedures from a New England cohort. Models had cross-validated C-statistics of 0.74 (95% CI: 0.74-0.75) for AKI, 0.83 (95% CI: 0.82-0.84) for AKIN2, 0.74 (95% CI: 0.74-0.75) for contrast-induced nephropathy, and 0.89 (95% CI: 0.87-0.90) for dialysis. We developed a robust, externally validated clinical prediction model for AKI following cardiac catheterization or percutaneous coronary intervention to automatically identify high-risk patients before and immediately after a procedure in the Veterans Health Administration. Work is ongoing to incorporate these models into routine clinical practice. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

External validation of blood eosinophils, FE(NO) and serum periostin as surrogates for sputum eosinophils in asthma.

PubMed

Wagener, A H; de Nijs, S B; Lutter, R; Sousa, A R; Weersink, E J M; Bel, E H; Sterk, P J

2015-02-01

Monitoring sputum eosinophils in asthma predicts exacerbations and improves management of asthma. Thus far, blood eosinophils and FE(NO) show contradictory results in predicting eosinophilic airway inflammation. More recently, serum periostin was proposed as a novel biomarker for eosinophilic inflammation. Quantifying the mutual relationships of blood eosinophils, FE(NO), and serum periostin with sputum eosinophils by external validation in two independent cohorts across various severities of asthma. The first cohort consisted of 110 patients with mild to moderate asthma (external validation cohort). The replication cohort consisted of 37 patients with moderate to severe asthma. Both cohorts were evaluated cross-sectionally. Sputum was induced for the assessment of eosinophils. In parallel, blood eosinophil counts, serum periostin concentrations and FENO were assessed. The diagnostic accuracy of these markers to identify eosinophilic asthma (sputum eosinophils ≥3%) was calculated using receiver operating characteristics area under the curve (ROC AUC). In the external validation cohort, ROC AUC for blood eosinophils was 89% (p<0.001) and for FE(NO) level 78% (p<0.001) to detect sputum eosinophilia ≥3%. Serum periostin was not able to distinguish eosinophilic from non-eosinophilic airway inflammation (ROC AUC=55%, p=0.44). When combining these three variables, no improvement was seen. The diagnostic value of blood eosinophils was confirmed in the replication cohort (ROC AUC 85%, p<0.001). In patients with mild to moderate asthma, as well as patients with more severe asthma, blood eosinophils had the highest accuracy in the identification of sputum eosinophilia in asthma. The use of blood eosinophils can facilitate individualised treatment and management of asthma. NTR1846 and NTR2364. 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.

Classification of patients with sepsis according to blood genomic endotype: a prospective cohort study.

PubMed

Scicluna, Brendon P; van Vught, Lonneke A; Zwinderman, Aeilko H; Wiewel, Maryse A; Davenport, Emma E; Burnham, Katie L; Nürnberg, Peter; Schultz, Marcus J; Horn, Janneke; Cremer, Olaf L; Bonten, Marc J; Hinds, Charles J; Wong, Hector R; Knight, Julian C; van der Poll, Tom

2017-10-01

Host responses during sepsis are highly heterogeneous, which hampers the identification of patients at high risk of mortality and their selection for targeted therapies. In this study, we aimed to identify biologically relevant molecular endotypes in patients with sepsis. This was a prospective observational cohort study that included consecutive patients admitted for sepsis to two intensive care units (ICUs) in the Netherlands between Jan 1, 2011, and July 20, 2012 (discovery and first validation cohorts) and patients admitted with sepsis due to community-acquired pneumonia to 29 ICUs in the UK (second validation cohort). We generated genome-wide blood gene expression profiles from admission samples and analysed them by unsupervised consensus clustering and machine learning. The primary objective of this study was to establish endotypes for patients with sepsis, and assess the association of these endotypes with clinical traits and survival outcomes. We also established candidate biomarkers for the endotypes to allow identification of patient endotypes in clinical practice. The discovery cohort had 306 patients, the first validation cohort had 216, and the second validation cohort had 265 patients. Four molecular endotypes for sepsis, designated Mars1-4, were identified in the discovery cohort, and were associated with 28-day mortality (log-rank p=0·022). In the discovery cohort, the worst outcome was found for patients classified as having a Mars1 endotype, and at 28 days, 35 (39%) of 90 people with a Mars1 endotype had died (hazard ratio [HR] vs all other endotypes 1·86 [95% CI 1·21-2·86]; p=0·0045), compared with 23 (22%) of 105 people with a Mars2 endotype (HR 0·64 [0·40-1·04]; p=0·061), 16 (23%) of 71 people with a Mars3 endotype (HR 0·71 [0·41-1·22]; p=0·19), and 13 (33%) of 40 patients with a Mars4 endotype (HR 1·13 [0·63-2·04]; p=0·69). Analysis of the net reclassification improvement using a combined clinical and endotype model

Predictive and construct validity of the Bayley Scales of Infant Development and the Wechsler Preschool and Primary Scale of Intelligence with the Taiwan Birth Cohort Study instrument.

PubMed

Lung, For-Wey; Chen, Po-Fei; Shu, Bih-Ching

2012-08-01

This study aimed to investigate the concurrent validity of the parent-report Taiwan Birth Cohort Study Developmental Instrument (TBCS-DI) with the Bayley Scales of Infant Development-Second Edition (BSID-II) and the Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R) at 6, 18, 36, and 60 months. 100 children were recruited at 6 months, 88 children followed-up at 18 months, 71 at 36 months, and 53 at 60 months. Longitudinally, the parent-report TBCS-DI, with the professional psychological assessments of the BSID-II and the WPPSI-R showed predictive validity. Looking at each time point in cross section, at 6 and 18 months the TBCS-DI had good concurrent validity with the BSID-II, and at 36 and 60 months the TBCS-DI was correlated only with the motor and performance domains of the BSID-II and WPPSI-R. With further investigation, the TBCS-DI may be used both in research and in clinical settings.

A validated case definition for chronic rhinosinusitis in administrative data: a Canadian perspective.

PubMed

Rudmik, Luke; Xu, Yuan; Kukec, Edward; Liu, Mingfu; Dean, Stafford; Quan, Hude

2016-11-01

Pharmacoepidemiological research using administrative databases has become increasingly popular for chronic rhinosinusitis (CRS); however, without a validated case definition the cohort evaluated may be inaccurate resulting in biased and incorrect outcomes. The objective of this study was to develop and validate a generalizable administrative database case definition for CRS using International Classification of Diseases, 9th edition (ICD-9)-coded claims. A random sample of 100 patients with a guideline-based diagnosis of CRS and 100 control patients were selected and then linked to a Canadian physician claims database from March 31, 2010, to March 31, 2015. The proportion of CRS ICD-9-coded claims (473.x and 471.x) for each of these 200 patients were reviewed and the validity of 7 different ICD-9-based coding algorithms was evaluated. The CRS case definition of ≥2 claims with a CRS ICD-9 code (471.x or 473.x) within 2 years of the reference case provides a balanced validity with a sensitivity of 77% and specificity of 79%. Applying this CRS case definition to the claims database produced a CRS cohort of 51,000 patients with characteristics that were consistent with published demographics and rates of comorbid asthma, allergic rhinitis, and depression. This study has validated several coding algorithms; based on the results a case definition of ≥2 physician claims of CRS (ICD-9 of 471.x or 473.x) within 2 years provides an optimal level of validity. Future studies will need to validate this administrative case definition from different health system perspectives and using larger retrospective chart reviews from multiple providers. © 2016 ARS-AAOA, LLC.

Exercise and the Prevention of Depression: Results of the HUNT Cohort Study.

PubMed

Harvey, Samuel B; Øverland, Simon; Hatch, Stephani L; Wessely, Simon; Mykletun, Arnstein; Hotopf, Matthew

2018-01-01

The purpose of the present study was to address 1) whether exercise provides protection against new-onset depression and anxiety and 2) if so, the intensity and amount of exercise required to gain protection and, lastly, 3) the mechanisms that underlie any association. A "healthy" cohort of 33,908 adults, selected on the basis of having no symptoms of common mental disorder or limiting physical health conditions, was prospectively followed for 11 years. Validated measures of exercise, depression, anxiety, and a range of potential confounding and mediating factors were collected. Undertaking regular leisure-time exercise was associated with reduced incidence of future depression but not anxiety. The majority of this protective effect occurred at low levels of exercise and was observed regardless of intensity. After adjustment for confounders, the population attributable fraction suggests that, assuming the relationship is causal, 12% of future cases of depression could have been prevented if all participants had engaged in at least 1 hour of physical activity each week. The social and physical health benefits of exercise explained a small proportion of the protective effect. Previously proposed biological mechanisms, such as alterations in parasympathetic vagal tone, did not appear to have a role in explaining the protection against depression. Regular leisure-time exercise of any intensity provides protection against future depression but not anxiety. Relatively modest changes in population levels of exercise may have important public mental health benefits and prevent a substantial number of new cases of depression.

Malignant melanoma risk after exposure to fertility drugs: results from a large Danish cohort study.

PubMed

Hannibal, Charlotte Gerd; Jensen, Allan; Sharif, Heidi; Kjaer, Susanne Krüger

2008-09-01

The aim was to examine the effects of fertility drugs on malignant melanoma risk using data from the largest cohort of infertile women to date. A cohort of 54,362 women with infertility problems referred to Danish fertility clinics in the period 1963-1998 was established. A detailed data collection including information about type and amount of treatment was conducted. Using case-cohort techniques, we calculated rate ratios (RRs) of malignant melanoma associated with different fertility drugs after adjustment for parity status. 112 malignant melanomas were identified during follow-up through 2000. Use of clomiphene, gonadotrophins, hCG or GnRH did not affect risk of malignant melanoma significantly. When stratifying for parity, however, use of gonadotrophins (RR = 2.29; CI: 1.16-4.52) or GnRH (RR = 3.26; 95% CI: 1.50-7.09) among parous women was associated with a significant increased risk. For all groups of fertility drugs, we found no association with number of cycles of use or years since first use (latency). Our findings showed no strong association between malignant melanoma risk and use of fertility drugs, although the results indicated that use of gonadotrophins or GnRH might increase risk in parous women. Longer follow-up is needed to confirm our findings.

Visual analogue scales for interstitial lung disease: a prospective validation study.

PubMed

Yates, Helen; Adamali, Huzaifa I; Maskell, Nick; Barratt, Shaney; Sharp, Charles

2018-05-16

Visual analogue scales (VAS) are simple symptom assessment tools which have not been validated in interstitial lung disease (ILD). Simple measures of ILD disease burden would be valuable for non-specialist clinicians monitoring disease away from ILD specialist centres. To validate VAS to assess change in dyspnoea, cough and fatigue in ILD, and to define the minimal clinically important difference (MCID) for change in these. 64 patients with ILD completed VAS for dyspnoea, cough and fatigue. Baseline King's Brief ILD questionnaire (K-BILD) scores, lung function and 6-minute walk test results were collected. Tests were repeated 3-6 months later, in addition to a 7-point Likert scale. The MCID was estimated using median change in VAS in patients who reported "small but just worthwhile change" in symptoms at follow-up. Methods were repeated in a validation cohort of 31 ILD patients to confirm findings. VAS scores were significantly higher for patients who reported a "small but just worthwhile change" in symptoms versus "no change" or "not worthwhile change" (p < 0.01). The MCID for VAS Dyspnoea was estimated as 22.0mm and 14.5mm for VAS Fatigue. These results were reproducible in the validation cohort. Results were not significant for VAS Cough. Change in VAS Dyspnoea correlated with change in K-BILD (r=-0.51, p < 0.01), forced vital capacity (r=-0.32, p = 0.01) and 6-minute walking distance (r=-0.37, p = 0.01). The VAS is valid for assessing change in dyspnoea and fatigue in ILD. The MCID is estimated as 22.0mm for dyspnoea and 14.5mm for fatigue. This could be used to monitor disease in settings away from ILD specialist review.

42 CFR 493.569 - Consequences of a finding of noncompliance as a result of a validation inspection.

Code of Federal Regulations, 2014 CFR

2014-10-01

... result of a validation inspection. 493.569 Section 493.569 Public Health CENTERS FOR MEDICARE & MEDICAID... validation inspection. (a) Laboratory with a certificate of accreditation. If a validation inspection results... validation inspection results in a finding that a CLIA-exempt laboratory is out of compliance with one or...

42 CFR 493.569 - Consequences of a finding of noncompliance as a result of a validation inspection.

Code of Federal Regulations, 2013 CFR

2013-10-01

... result of a validation inspection. 493.569 Section 493.569 Public Health CENTERS FOR MEDICARE & MEDICAID... validation inspection. (a) Laboratory with a certificate of accreditation. If a validation inspection results... validation inspection results in a finding that a CLIA-exempt laboratory is out of compliance with one or...

42 CFR 493.569 - Consequences of a finding of noncompliance as a result of a validation inspection.

Code of Federal Regulations, 2012 CFR

2012-10-01

... result of a validation inspection. 493.569 Section 493.569 Public Health CENTERS FOR MEDICARE & MEDICAID... validation inspection. (a) Laboratory with a certificate of accreditation. If a validation inspection results... validation inspection results in a finding that a CLIA-exempt laboratory is out of compliance with one or...

42 CFR 493.569 - Consequences of a finding of noncompliance as a result of a validation inspection.

Code of Federal Regulations, 2011 CFR

2011-10-01

... result of a validation inspection. 493.569 Section 493.569 Public Health CENTERS FOR MEDICARE & MEDICAID... validation inspection. (a) Laboratory with a certificate of accreditation. If a validation inspection results... validation inspection results in a finding that a CLIA-exempt laboratory is out of compliance with one or...

42 CFR 493.569 - Consequences of a finding of noncompliance as a result of a validation inspection.

Code of Federal Regulations, 2010 CFR

2010-10-01

... result of a validation inspection. 493.569 Section 493.569 Public Health CENTERS FOR MEDICARE & MEDICAID... validation inspection. (a) Laboratory with a certificate of accreditation. If a validation inspection results... validation inspection results in a finding that a CLIA-exempt laboratory is out of compliance with one or...

The U.S. Department of Veterans' Affairs depleted uranium exposed cohort at 25 Years: Longitudinal surveillance results

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

McDiarmid, Melissa A.; Gaitens, Joanna M.; Hines,

Background: A small group of Gulf War I veterans wounded in depleted uranium (DU) friendly-fire incidents have been monitored for health changes in a clinical surveillance program at the Veterans Affairs Medical Center, Baltimore since 1994. Methods: During the spring of 2015, an in-patient clinical surveillance protocol was performed on 36 members of the cohort, including exposure monitoring for total and isotopic uranium concentrations in urine and a comprehensive assessment of health outcomes. Results: On-going mobilization of U from embedded fragments is evidenced by elevated urine U concentrations. The DU isotopic signature is observed principally in participants possessing embedded fragments.more » Those with only an inhalation exposure have lower urine U concentration and a natural isotopic signature. Conclusions: At 25 years since first exposure to DU, an aging cohort of military veterans continues to show no U-related health effects in known target organs of U toxicity. As U body burden continues to accrue from in-situ mobilization from metal fragment depots, and increases with exposure duration, critical tissue-specific U concentration thresholds may be reached, thus recommending on-going surveillance of this veteran cohort. - Highlights: • Gulf War I veterans wounded with depleted uranium are monitored for health changes. • In 2015 in-patient clinical surveillance was performed on 36 members of the cohort. • Mobilization of U from embedded fragments is evidenced by elevated U in urine. • This cohort of continues to show no U-related health effects.« less

Validation of serum progesterone <35nmol/L as a predictor of miscarriage among women with threatened miscarriage.

PubMed

Lek, Sze Min; Ku, Chee Wai; Allen, John C; Malhotra, Rahul; Tan, Nguan Soon; Østbye, Truls; Tan, Thiam Chye

2017-03-06

Our recent paper, based on a pilot cohort of 119 women, showed that serum progesterone <35 nmol/L was prognostic of spontaneous miscarriage by 16 weeks in women with threatened miscarriage in early pregnancy. Using a larger cohort of women from the same setting (validation cohort), we aim to assess the validity of serum progesterone <35 nmol/L with the outcome of spontaneous miscarriage by 16 weeks. In a prospective cohort study, 360 pregnant women presenting with threatened miscarriage between gestation weeks 6-10 at a tertiary hospital emergency unit for women in Singapore were recruited for this study. The main outcome measure measured is spontaneous miscarriage prior to week 16 of gestation. Area under the ROC curve (AUC) and test characteristics (sensitivity, specificity, positive and negative predictive value) at a serum progesterone cutpoint of <35 nmol/L for predicting high and low risk of spontaneous miscarriage by 16 weeks were compared between the Pilot and Validation cohorts. Test characteristics and AUC values using serum progesterone <35 nmol/L in the validation cohort were not significantly different from those in the Pilot cohort, demonstrating excellent accuracy and reproducibility of the proposed serum progesterone cut-off level. The cut-off value for serum progesterone (35 nmol/L) demonstrated clinical relevance and allow clinicians to stratify patients into high and low risk groups for spontaneous miscarriage.

An international prospective cohort study of mobile phone users and health (COSMOS): Factors affecting validity of self-reported mobile phone use.

PubMed

Toledano, Mireille B; Auvinen, Anssi; Tettamanti, Giorgio; Cao, Yang; Feychting, Maria; Ahlbom, Anders; Fremling, Karin; Heinävaara, Sirpa; Kojo, Katja; Knowles, Gemma; Smith, Rachel B; Schüz, Joachim; Johansen, Christoffer; Poulsen, Aslak Harbo; Deltour, Isabelle; Vermeulen, Roel; Kromhout, Hans; Elliott, Paul; Hillert, Lena

2018-01-01

This study investigates validity of self-reported mobile phone use in a subset of 75 993 adults from the COSMOS cohort study. Agreement between self-reported and operator-derived mobile call frequency and duration for a 3-month period was assessed using Cohen's weighted Kappa (κ). Sensitivity and specificity of both self-reported high (≥10 calls/day or ≥4h/week) and low (≤6 calls/week or <30min/week) mobile phone use were calculated, as compared to operator data. For users of one mobile phone, agreement was fair for call frequency (κ=0.35, 95% CI: 0.35, 0.36) and moderate for call duration (κ=0.50, 95% CI: 0.49, 0.50). Self-reported low call frequency and duration demonstrated high sensitivity (87% and 76% respectively), but for high call frequency and duration sensitivity was lower (38% and 56% respectively), reflecting a tendency for greater underestimation than overestimation. Validity of self-reported mobile phone use was lower in women, younger age groups and those reporting symptoms during/shortly after using a mobile phone. This study highlights the ongoing value of using self-report data to measure mobile phone use. Furthermore, compared to continuous scale estimates used by previous studies, categorical response options used in COSMOS appear to improve validity considerably, most likely by preventing unrealistically high estimates from being reported. Copyright © 2017 Elsevier GmbH. All rights reserved.

ExEP yield modeling tool and validation test results

NASA Astrophysics Data System (ADS)

Morgan, Rhonda; Turmon, Michael; Delacroix, Christian; Savransky, Dmitry; Garrett, Daniel; Lowrance, Patrick; Liu, Xiang Cate; Nunez, Paul

2017-09-01

EXOSIMS is an open-source simulation tool for parametric modeling of the detection yield and characterization of exoplanets. EXOSIMS has been adopted by the Exoplanet Exploration Programs Standards Definition and Evaluation Team (ExSDET) as a common mechanism for comparison of exoplanet mission concept studies. To ensure trustworthiness of the tool, we developed a validation test plan that leverages the Python-language unit-test framework, utilizes integration tests for selected module interactions, and performs end-to-end crossvalidation with other yield tools. This paper presents the test methods and results, with the physics-based tests such as photometry and integration time calculation treated in detail and the functional tests treated summarily. The test case utilized a 4m unobscured telescope with an idealized coronagraph and an exoplanet population from the IPAC radial velocity (RV) exoplanet catalog. The known RV planets were set at quadrature to allow deterministic validation of the calculation of physical parameters, such as working angle, photon counts and integration time. The observing keepout region was tested by generating plots and movies of the targets and the keepout zone over a year. Although the keepout integration test required the interpretation of a user, the test revealed problems in the L2 halo orbit and the parameterization of keepout applied to some solar system bodies, which the development team was able to address. The validation testing of EXOSIMS was performed iteratively with the developers of EXOSIMS and resulted in a more robust, stable, and trustworthy tool that the exoplanet community can use to simulate exoplanet direct-detection missions from probe class, to WFIRST, up to large mission concepts such as HabEx and LUVOIR.

Implications of failure to achieve a result from prenatal maternal serum cell-free DNA testing: a historical cohort study.

PubMed

Chan, N; Smet, M-E; Sandow, R; da Silva Costa, F; McLennan, A

2017-11-01

To investigate the pregnancy outcomes in a cohort of women who failed to obtain a result in non-invasive prenatal testing (NIPT). Historical cohort study. A multicentre private practice in Sydney, Australia. Women who failed to obtain a result from NIPT (n = 131). The maternal characteristics, antenatal investigations and pregnancy outcomes for these women were compared with those who obtained a result at the same practice and to the general Australian obstetric population. Antenatal investigations: pregnancy-associated plasma protein-A (PAPP-A), free β-human chorionic gonadotrophin (β-hCG), placental growth factor (PlGF), uterine artery pulsatility index (PI), mean arterial pressure (MAP). Pregnancy outcomes: chromosomal abnormality, pre-eclampsia, gestational diabetes, small-for-gestational-age (SGA), preterm delivery. Only 1.1% of NIPT samples failed to return a result. This cohort was significantly older and had significantly increased weight compared with the general Australian obstetric population. Pregnancy outcomes were available for 94% of the cohort. There were significantly higher rates of chromosomal aneuploidies (6.5% versus 0.2%, P < 0.0001), pre-eclampsia (11% versus 1.5%, P < 0.0001) and gestational diabetes (23% versus 7.5%, P < 0.0001) compared with the general obstetric population. Rates of preterm delivery and SGA were elevated but did not reach significance. Antenatal investigations demonstrated decreased PAPP-A MoM (0.75 versus 1.14, P < 0.0001), decreased free β-hCG (0.71 versus 1.01, P < 0.0001) and increased uterine artery PI (1.79 versus 1.65, P = 0.02). Women who fail to obtain a result from NIPT are at increased risk of adverse pregnancy outcomes, in particular chromosomal aneuploidy, gestational diabetes and pre-eclampsia. None received. Women who fail to obtain a result from cell-free DNA NIPT are at increased risk of adverse pregnancy outcomes. © 2017 Royal College of Obstetricians and Gynaecologists.

Double Cross-Validation in Multiple Regression: A Method of Estimating the Stability of Results.

ERIC Educational Resources Information Center

Rowell, R. Kevin

In multiple regression analysis, where resulting predictive equation effectiveness is subject to shrinkage, it is especially important to evaluate result replicability. Double cross-validation is an empirical method by which an estimate of invariance or stability can be obtained from research data. A procedure for double cross-validation is…

Plasma Concentrations and Dietary Intakes of Choline and Betaine in Association With Atrial Fibrillation Risk: Results From 3 Prospective Cohorts With Different Health Profiles.

PubMed

Zuo, Hui; Svingen, Gard F T; Tell, Grethe S; Ueland, Per M; Vollset, Stein E; Pedersen, Eva R; Ulvik, Arve; Meyer, Klaus; Nordrehaug, Jan E; Nilsen, Dennis W T; Bønaa, Kaare H; Nygård, Ottar

2018-04-12

Although choline metabolism has been associated with atherosclerotic heart disease, less research attention has been paid to the associations of choline and its oxidative metabolite betaine with cardiac arrhythmias. We evaluated associations of plasma concentrations and dietary intakes of choline and betaine with long-term atrial fibrillation (AF) risk in a community-based cohort, HUSK ([the Hordaland Health Study] n=6949), and validated the findings in 2 patient cohorts: the Western Norway Coronary Angiography Cohort (n=4164) and the NORVIT (Norwegian B-Vitamin) Trial (n=3733). Information on AF was obtained from the CVDNOR (Cardiovascular Disease in Norway) project. In HUSK, WECAC (Western Norway Coronary Angiography Cohort), and NORVIT, 552, 411, and 663 AF cases were identified during a median follow-up time of 10.9, 7.3, and, 8.7 years, respectively. Plasma concentrations of choline and betaine were significantly positively associated with later AF risk after multivariable adjustments in HUSK. Such associations were independently replicated in the 2 external prospective patient cohorts. The pooled hazard ratio was 1.13 (95% confidence interval 1.08-1.19, P <0.001) and 1.16 (95% confidence interval 1.10-1.22, P <0.001) per SD increment for log-transformed choline and betaine, respectively. Moreover, dietary intake of choline was marginally associated with AF risk (pooled hazard ratio 1.29, 95% confidence interval 1.01-1.66, fifth versus first quintile), whereas no significant association was observed between dietary betaine and AF risk. Our findings indicate that plasma concentrations as well as dietary intake of choline, but not betaine, are associated with subsequent risk of AF, suggesting a potential role of choline metabolism in the pathogenesis of AF. URL: https://www.clinicaltrials.gov.Unique identifier: NCT00671346. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Validation Results for LEWICE 2.0. [Supplement

NASA Technical Reports Server (NTRS)

Wright, William B.; Rutkowski, Adam

1999-01-01

Two CD-ROMs contain experimental ice shapes and code prediction used for validation of LEWICE 2.0 (see NASA/CR-1999-208690, CASI ID 19990021235). The data include ice shapes for both experiment and for LEWICE, all of the input and output files for the LEWICE cases, JPG files of all plots generated, an electronic copy of the text of the validation report, and a Microsoft Excel(R) spreadsheet containing all of the quantitative measurements taken. The LEWICE source code and executable are not contained on the discs.

Endometrial cancer risk prediction including serum-based biomarkers: results from the EPIC cohort.

PubMed

Fortner, Renée T; Hüsing, Anika; Kühn, Tilman; Konar, Meric; Overvad, Kim; Tjønneland, Anne; Hansen, Louise; Boutron-Ruault, Marie-Christine; Severi, Gianluca; Fournier, Agnès; Boeing, Heiner; Trichopoulou, Antonia; Benetou, Vasiliki; Orfanos, Philippos; Masala, Giovanna; Agnoli, Claudia; Mattiello, Amalia; Tumino, Rosario; Sacerdote, Carlotta; Bueno-de-Mesquita, H B As; Peeters, Petra H M; Weiderpass, Elisabete; Gram, Inger T; Gavrilyuk, Oxana; Quirós, J Ramón; Maria Huerta, José; Ardanaz, Eva; Larrañaga, Nerea; Lujan-Barroso, Leila; Sánchez-Cantalejo, Emilio; Butt, Salma Tunå; Borgquist, Signe; Idahl, Annika; Lundin, Eva; Khaw, Kay-Tee; Allen, Naomi E; Rinaldi, Sabina; Dossus, Laure; Gunter, Marc; Merritt, Melissa A; Tzoulaki, Ioanna; Riboli, Elio; Kaaks, Rudolf

2017-03-15

Endometrial cancer risk prediction models including lifestyle, anthropometric and reproductive factors have limited discrimination. Adding biomarker data to these models may improve predictive capacity; to our knowledge, this has not been investigated for endometrial cancer. Using a nested case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, we investigated the improvement in discrimination gained by adding serum biomarker concentrations to risk estimates derived from an existing risk prediction model based on epidemiologic factors. Serum concentrations of sex steroid hormones, metabolic markers, growth factors, adipokines and cytokines were evaluated in a step-wise backward selection process; biomarkers were retained at p < 0.157 indicating improvement in the Akaike information criterion (AIC). Improvement in discrimination was assessed using the C-statistic for all biomarkers alone, and change in C-statistic from addition of biomarkers to preexisting absolute risk estimates. We used internal validation with bootstrapping (1000-fold) to adjust for over-fitting. Adiponectin, estrone, interleukin-1 receptor antagonist, tumor necrosis factor-alpha and triglycerides were selected into the model. After accounting for over-fitting, discrimination was improved by 2.0 percentage points when all evaluated biomarkers were included and 1.7 percentage points in the model including the selected biomarkers. Models including etiologic markers on independent pathways and genetic markers may further improve discrimination. © 2016 UICC.

Development and External Validation of a Prognostic Nomogram for Metastatic Uveal Melanoma

PubMed Central

Valpione, Sara; Moser, Justin C.; Parrozzani, Raffaele; Bazzi, Marco; Mansfield, Aaron S.; Mocellin, Simone; Pigozzo, Jacopo; Midena, Edoardo; Markovic, Svetomir N.; Aliberti, Camillo; Campana, Luca G.; Chiarion-Sileni, Vanna

2015-01-01

Background Approximately 50% of patients with uveal melanoma (UM) will develop metastatic disease, usually involving the liver. The outcome of metastatic UM (mUM) is generally poor and no standard therapy has been established. Additionally, clinicians lack a validated prognostic tool to evaluate these patients. The aim of this work was to develop a reliable prognostic nomogram for clinicians. Patients and Methods Two cohorts of mUM patients, from Veneto Oncology Institute (IOV) (N=152) and Mayo Clinic (MC) (N=102), were analyzed to develop and externally validate, a prognostic nomogram. Results The median survival of mUM was 17.2 months in the IOV cohort and 19.7 in the MC cohort. Percentage of liver involvement (HR 1.6), elevated levels of serum LDH (HR 1.6), and a WHO performance status=1 (HR 1.5) or 2–3 (HR 4.6) were associated with worse prognosis. Longer disease-free interval from diagnosis of UM to that of mUM conferred a survival advantage (HR 0.9). The nomogram had a concordance probability of 0.75 (SE .006) in the development dataset (IOV), and 0.80 (SE .009) in the external validation (MC). Nomogram predictions were well calibrated. Conclusions The nomogram, which includes percentage of liver involvement, LDH levels, WHO performance status and disease free-interval accurately predicts the prognosis of mUM and could be useful for decision-making and risk stratification for clinical trials. PMID:25780931

Perioperative Respiratory Adverse Events in Pediatric Ambulatory Anesthesia: Development and Validation of a Risk Prediction Tool.

PubMed

Subramanyam, Rajeev; Yeramaneni, Samrat; Hossain, Mohamed Monir; Anneken, Amy M; Varughese, Anna M

2016-05-01

Perioperative respiratory adverse events (PRAEs) are the most common cause of serious adverse events in children receiving anesthesia. Our primary aim of this study was to develop and validate a risk prediction tool for the occurrence of PRAE from the onset of anesthesia induction until discharge from the postanesthesia care unit in children younger than 18 years undergoing elective ambulatory anesthesia for surgery and radiology. The incidence of PRAE was studied. We analyzed data from 19,059 patients from our department's quality improvement database. The predictor variables were age, sex, ASA physical status, morbid obesity, preexisting pulmonary disorder, preexisting neurologic disorder, and location of ambulatory anesthesia (surgery or radiology). Composite PRAE was defined as the presence of any 1 of the following events: intraoperative bronchospasm, intraoperative laryngospasm, postoperative apnea, postoperative laryngospasm, postoperative bronchospasm, or postoperative prolonged oxygen requirement. Development and validation of the risk prediction tool for PRAE were performed using a split sampling technique to split the database into 2 independent cohorts based on the year when the patient received ambulatory anesthesia for surgery and radiology using logistic regression. A risk score was developed based on the regression coefficients from the validation tool. The performance of the risk prediction tool was assessed by using tests of discrimination and calibration. The overall incidence of composite PRAE was 2.8%. The derivation cohort included 8904 patients, and the validation cohort included 10,155 patients. The risk of PRAE was 3.9% in the development cohort and 1.8% in the validation cohort. Age ≤ 3 years (versus >3 years), ASA physical status II or III (versus ASA physical status I), morbid obesity, preexisting pulmonary disorder, and surgery (versus radiology) significantly predicted the occurrence of PRAE in a multivariable logistic regression

Online Prediction of Health Care Utilization in the Next Six Months Based on Electronic Health Record Information: A Cohort and Validation Study

PubMed Central

Hu, Zhongkai; Hao, Shiying; Jin, Bo; Shin, Andrew Young; Zhu, Chunqing; Huang, Min; Wang, Yue; Zheng, Le; Dai, Dorothy; Culver, Devore S; Alfreds, Shaun T; Rogow, Todd; Stearns, Frank

2015-01-01

Background The increasing rate of health care expenditures in the United States has placed a significant burden on the nation’s economy. Predicting future health care utilization of patients can provide useful information to better understand and manage overall health care deliveries and clinical resource allocation. Objective This study developed an electronic medical record (EMR)-based online risk model predictive of resource utilization for patients in Maine in the next 6 months across all payers, all diseases, and all demographic groups. Methods In the HealthInfoNet, Maine’s health information exchange (HIE), a retrospective cohort of 1,273,114 patients was constructed with the preceding 12-month EMR. Each patient’s next 6-month (between January 1, 2013 and June 30, 2013) health care resource utilization was retrospectively scored ranging from 0 to 100 and a decision tree–based predictive model was developed. Our model was later integrated in the Maine HIE population exploration system to allow a prospective validation analysis of 1,358,153 patients by forecasting their next 6-month risk of resource utilization between July 1, 2013 and December 31, 2013. Results Prospectively predicted risks, on either an individual level or a population (per 1000 patients) level, were consistent with the next 6-month resource utilization distributions and the clinical patterns at the population level. Results demonstrated the strong correlation between its care resource utilization and our risk scores, supporting the effectiveness of our model. With the online population risk monitoring enterprise dashboards, the effectiveness of the predictive algorithm has been validated by clinicians and caregivers in the State of Maine. Conclusions The model and associated online applications were designed for tracking the evolving nature of total population risk, in a longitudinal manner, for health care resource utilization. It will enable more effective care management

Simultaneous Validation of Seven Physical Activity Questionnaires Used in Japanese Cohorts for Estimating Energy Expenditure: A Doubly Labeled Water Study.

PubMed

Sasai, Hiroyuki; Nakata, Yoshio; Murakami, Haruka; Kawakami, Ryoko; Nakae, Satoshi; Tanaka, Shigeho; Ishikawa-Takata, Kazuko; Yamada, Yosuke; Miyachi, Motohiko

2018-04-28

Physical activity questionnaires (PAQs) used in large-scale Japanese cohorts have rarely been simultaneously validated against the gold standard doubly labeled water (DLW) method. This study examined the validity of seven PAQs used in Japan for estimating energy expenditure against the DLW method. Twenty healthy Japanese adults (9 men; mean age, 32.4 [standard deviation {SD}, 9.4] years, mainly researchers and students) participated in this study. Fifteen-day daily total energy expenditure (TEE) and basal metabolic rate (BMR) were measured using the DLW method and a metabolic chamber, respectively. Activity energy expenditure (AEE) was calculated as TEE - BMR - 0.1 × TEE. Seven PAQs were self-administered to estimate TEE and AEE. The mean measured values of TEE and AEE were 2,294 (SD, 318) kcal/day and 721 (SD, 161) kcal/day, respectively. All of the PAQs indicated moderate-to-strong correlations with the DLW method in TEE (rho = 0.57-0.84). Two PAQs (Japan Public Health Center Study [JPHC]-PAQ Short and JPHC-PAQ Long) showed significant equivalence in TEE and moderate intra-class correlation coefficients (ICC). None of the PAQs showed significantly equivalent AEE estimates, with differences ranging from -547 to 77 kcal/day. Correlations and ICCs in AEE were mostly weak or fair (rho = 0.02-0.54, and ICC = 0.00-0.44). Only JPHC-PAQ Short provided significant and fair agreement with the DLW method. TEE estimated by the PAQs showed moderate or strong correlations with the results of DLW. Two PAQs showed equivalent TEE and moderate agreement. None of the PAQs showed equivalent AEE estimation to the gold standard, with weak-to-fair correlations and agreements. Further studies with larger sample sizes are needed to confirm these findings.

Validation environment for AIPS/ALS: Implementation and results

NASA Technical Reports Server (NTRS)

Segall, Zary; Siewiorek, Daniel; Caplan, Eddie; Chung, Alan; Czeck, Edward; Vrsalovic, Dalibor

1990-01-01

The work is presented which was performed in porting the Fault Injection-based Automated Testing (FIAT) and Programming and Instrumentation Environments (PIE) validation tools, to the Advanced Information Processing System (AIPS) in the context of the Ada Language System (ALS) application, as well as an initial fault free validation of the available AIPS system. The PIE components implemented on AIPS provide the monitoring mechanisms required for validation. These mechanisms represent a substantial portion of the FIAT system. Moreover, these are required for the implementation of the FIAT environment on AIPS. Using these components, an initial fault free validation of the AIPS system was performed. The implementation is described of the FIAT/PIE system, configured for fault free validation of the AIPS fault tolerant computer system. The PIE components were modified to support the Ada language. A special purpose AIPS/Ada runtime monitoring and data collection was implemented. A number of initial Ada programs running on the PIE/AIPS system were implemented. The instrumentation of the Ada programs was accomplished automatically inside the PIE programming environment. PIE's on-line graphical views show vividly and accurately the performance characteristics of Ada programs, AIPS kernel and the application's interaction with the AIPS kernel. The data collection mechanisms were written in a high level language, Ada, and provide a high degree of flexibility for implementation under various system conditions.

Variations in Facebook Posting Patterns Across Validated Patient Health Conditions: A Prospective Cohort Study

PubMed Central

Smith, Robert J; Crutchley, Patrick; Schwartz, H Andrew; Ungar, Lyle; Shofer, Frances; Padrez, Kevin A

2017-01-01

Background Social media is emerging as an insightful platform for studying health. To develop targeted health interventions involving social media, we sought to identify the patient demographic and disease predictors of frequency of posting on Facebook. Objective The aims were to explore the language topics correlated with frequency of social media use across a cohort of social media users within a health care setting, evaluate the differences in the quantity of social media postings across individuals with different disease diagnoses, and determine if patients could accurately predict their own levels of social media engagement. Methods Patients seeking care at a single, academic, urban, tertiary care emergency department from March to October 2014 were queried on their willingness to share data from their Facebook accounts and electronic medical records (EMRs). For each participant, the total content of Facebook posts was extracted. Using the latent Dirichlet allocation natural language processing technique, Facebook language topics were correlated with frequency of Facebook use. The mean number of Facebook posts over 6 months prior to enrollment was then compared across validated health outcomes in the sample. Results A total of 695 patients consented to provide access to their EMR and social media data. Significantly correlated language topics among participants with the highest quartile of posts contained health terms, such as “cough,” “headaches,” and “insomnia.” When adjusted for demographics, individuals with a history of depression had significantly higher posts (mean 38, 95% CI 28-50) than individuals without a history of depression (mean 22, 95% CI 19-26, P=.001). Except for depression, across prevalent health outcomes in the sample (hypertension, diabetes, asthma), there were no significant posting differences between individuals with or without each condition. Conclusions High-frequency posters in our sample were more likely to post about

Validation results of satellite mock-up capturing experiment using nets

NASA Astrophysics Data System (ADS)

Medina, Alberto; Cercós, Lorenzo; Stefanescu, Raluca M.; Benvenuto, Riccardo; Pesce, Vincenzo; Marcon, Marco; Lavagna, Michèle; González, Iván; Rodríguez López, Nuria; Wormnes, Kjetil

2017-05-01

The PATENDER activity (Net parametric characterization and parabolic flight), funded by the European Space Agency (ESA) via its Clean Space initiative, was aiming to validate a simulation tool for designing nets for capturing space debris. This validation has been performed through a set of different experiments under microgravity conditions where a net was launched capturing and wrapping a satellite mock-up. This paper presents the architecture of the thrown-net dynamics simulator together with the set-up of the deployment experiment and its trajectory reconstruction results on a parabolic flight (Novespace A-310, June 2015). The simulator has been implemented within the Blender framework in order to provide a highly configurable tool, able to reproduce different scenarios for Active Debris Removal missions. The experiment has been performed over thirty parabolas offering around 22 s of zero-g conditions. Flexible meshed fabric structure (the net) ejected from a container and propelled by corner masses (the bullets) arranged around its circumference have been launched at different initial velocities and launching angles using a pneumatic-based dedicated mechanism (representing the chaser satellite) against a target mock-up (the target satellite). High-speed motion cameras were recording the experiment allowing 3D reconstruction of the net motion. The net knots have been coloured to allow the images post-process using colour segmentation, stereo matching and iterative closest point (ICP) for knots tracking. The final objective of the activity was the validation of the net deployment and wrapping simulator using images recorded during the parabolic flight. The high-resolution images acquired have been post-processed to determine accurately the initial conditions and generate the reference data (position and velocity of all knots of the net along its deployment and wrapping of the target mock-up) for the simulator validation. The simulator has been properly

Derivation and validation of the prediabetes self-assessment screening score after acute pancreatitis (PERSEUS).

PubMed

Soo, Danielle H E; Pendharkar, Sayali A; Jivanji, Chirag J; Gillies, Nicola A; Windsor, John A; Petrov, Maxim S

2017-10-01

Approximately 40% of patients develop abnormal glucose metabolism after a single episode of acute pancreatitis. This study aimed to develop and validate a prediabetes self-assessment screening score for patients after acute pancreatitis. Data from non-overlapping training (n=82) and validation (n=80) cohorts were analysed. Univariate logistic and linear regression identified variables associated with prediabetes after acute pancreatitis. Multivariate logistic regression developed the score, ranging from 0 to 215. The area under the receiver-operating characteristic curve (AUROC), Hosmer-Lemeshow χ 2 statistic, and calibration plots were used to assess model discrimination and calibration. The developed score was validated using data from the validation cohort. The score had an AUROC of 0.88 (95% CI, 0.80-0.97) and Hosmer-Lemeshow χ 2 statistic of 5.75 (p=0.676). Patients with a score of ≥75 had a 94.1% probability of having prediabetes, and were 29 times more likely to have prediabetes than those with a score of <75. The AUROC in the validation cohort was 0.81 (95% CI, 0.70-0.92) and the Hosmer-Lemeshow χ 2 statistic was 5.50 (p=0.599). Model calibration of the score showed good calibration in both cohorts. The developed and validated score, called PERSEUS, is the first instrument to identify individuals who are at high risk of developing abnormal glucose metabolism following an episode of acute pancreatitis. Copyright © 2017 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Incidence and risk factors for type 2 diabetes mellitus in transitional Thailand: results from the Thai cohort study.

PubMed

Papier, Keren; Jordan, Susan; D'Este, Catherine; Bain, Chris; Peungson, Janya; Banwell, Cathy; Yiengprugsawan, Vasoontara; Seubsman, Sam-Ang; Sleigh, Adrian

2016-12-13

Type 2 diabetes mellitus (T2DM) is increasingly prevalent in countries undergoing rapid development, including Thailand. We assessed T2DM incidence over an 8-year period in a nationwide cohort of Thai adults. Thai Cohort Study participants were surveyed in 2005, 2009 and 2013. The analysed cohort members were aged (15-88), did not have diabetes in 2005 and were followed up by questionnaire in 2013 (n=39 507). T2DM was ascertained using self-report, which has been validated using physician interviews. We calculated the 8-year cumulative incidence of T2DM. Multivariable logistic regression assessed associations between potential risk factors and T2DM incidence. 8-year cumulative incidence of T2DM (2005 to 2013) was 177 per 10 000 (95% CI 164 to 190). Crude and age-standardised cumulative incidences of T2DM by sex were 249 per 10 000 (95% CI 226 to 272) and 222 per 10 000 (95% CI 219 to 225) for men; and 119 per 10 000 (95% CI 105 to 133) and 96 per 10 000 (95% CI 94 to 98) for women, respectively. T2DM increased significantly for both sexes with increasing age and body mass index (BMI) (p trend <0.001 for both). Residence in an urban area as a child associated with T2DM among men and women (OR=1.4, 95% CI 1.1 to 1.7 and OR=1.4, 95% CI 1.01 to 1.79); this was no longer statistically significant after adjusting for BMI. Among men, smoking (OR=1.7, 95% CI 1.3 to 2.2) and alcohol intake (OR=1.8, 95% CI 1.1 to 3.0) were associated with T2DM. This study found that the sociodemographic and lifestyle changes that have accompanied Thailand's economic development are associated with T2DM risk in a large cohort of Thai adults. Our findings highlight the need to address these transitions to prevent a further increase in the national incidence of T2DM, particularly among Thai men. 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/.

CpG Methylation Signature Predicts Recurrence in Early-Stage Hepatocellular Carcinoma: Results From a Multicenter Study.

PubMed

Qiu, Jiliang; Peng, Baogang; Tang, Yunqiang; Qian, Yeben; Guo, Pi; Li, Mengfeng; Luo, Junhang; Chen, Bin; Tang, Hui; Lu, Canliang; Cai, Muyan; Ke, Zunfu; He, Wei; Zheng, Yun; Xie, Dan; Li, Binkui; Yuan, Yunfei

2017-03-01

Purpose Early-stage hepatocellular carcinoma (E-HCC) is being diagnosed increasingly, and in one half of diagnosed patients, recurrence will develop. Thus, it is urgent to identify recurrence-related markers. We investigated the effectiveness of CpG methylation in predicting recurrence for patients with E-HCCs. Patients and Methods In total, 576 patients with E-HCC from four independent centers were sorted by three phases. In the discovery phase, 66 tumor samples were analyzed using the Illumina Methylation 450k Beadchip. Two algorithms, Least Absolute Shrinkage and Selector Operation and Support Vector Machine-Recursive Feature Elimination, were used to select significant CpGs. In the training phase, penalized Cox regression was used to further narrow CpGs into 140 samples. In the validation phase, candidate CpGs were validated using an internal cohort (n = 141) and two external cohorts (n = 191 and n =104). Results After combining the 46 CpGs selected by the Least Absolute Shrinkage and Selector Operation and the Support Vector Machine-Recursive Feature Elimination algorithms, three CpGs corresponding to SCAN domain containing 3, Src homology 3-domain growth factor receptor-bound 2-like interacting protein 1, and peptidase inhibitor 3 were highlighted as candidate predictors in the training phase. On the basis of the three CpGs, a methylation signature for E-HCC (MSEH) was developed to classify patients into high- and low-risk recurrence groups in the training cohort ( P < .001). The performance of MSEH was validated in the internal cohort ( P < .001) and in the two external cohorts ( P < .001; P = .002). Furthermore, a nomogram comprising MSEH, tumor differentiation, cirrhosis, hepatitis B virus surface antigen, and antivirus therapy was generated to predict the 5-year recurrence-free survival in the training cohort, and it performed well in the three validation cohorts (concordance index: 0.725, 0.697, and 0.693, respectively). Conclusion MSEH, a three

Development of Decision Support Formulas for the Prediction of Bladder Outlet Obstruction and Prostatic Surgery in Patients With Lower Urinary Tract Symptom/Benign Prostatic Hyperplasia: Part II, External Validation and Usability Testing of a Smartphone App.

PubMed

Choo, Min Soo; Jeong, Seong Jin; Cho, Sung Yong; Yoo, Changwon; Jeong, Chang Wook; Ku, Ja Hyeon; Oh, Seung-June

2017-04-01

We aimed to externally validate the prediction model we developed for having bladder outlet obstruction (BOO) and requiring prostatic surgery using 2 independent data sets from tertiary referral centers, and also aimed to validate a mobile app for using this model through usability testing. Formulas and nomograms predicting whether a subject has BOO and needs prostatic surgery were validated with an external validation cohort from Seoul National University Bundang Hospital and Seoul Metropolitan Government-Seoul National University Boramae Medical Center between January 2004 and April 2015. A smartphone-based app was developed, and 8 young urologists were enrolled for usability testing to identify any human factor issues of the app. A total of 642 patients were included in the external validation cohort. No significant differences were found in the baseline characteristics of major parameters between the original (n=1,179) and the external validation cohort, except for the maximal flow rate. Predictions of requiring prostatic surgery in the validation cohort showed a sensitivity of 80.6%, a specificity of 73.2%, a positive predictive value of 49.7%, and a negative predictive value of 92.0%, and area under receiver operating curve of 0.84. The calibration plot indicated that the predictions have good correspondence. The decision curve showed also a high net benefit. Similar evaluation results using the external validation cohort were seen in the predictions of having BOO. Overall results of the usability test demonstrated that the app was user-friendly with no major human factor issues. External validation of these newly developed a prediction model demonstrated a moderate level of discrimination, adequate calibration, and high net benefit gains for predicting both having BOO and requiring prostatic surgery. Also a smartphone app implementing the prediction model was user-friendly with no major human factor issue.

Glycemic index, glycemic load, and risk of type 2 diabetes: results from 3 large US cohorts and an updated meta-analysis123

PubMed Central

Bhupathiraju, Shilpa N; Tobias, Deirdre K; Malik, Vasanti S; Pan, An; Hruby, Adela; Manson, JoAnn E; Willett, Walter C; Hu, Frank B

2014-01-01

Background: Epidemiologic evidence for the relation between carbohydrate quality and risk of type 2 diabetes (T2D) has been mixed. Objective: We prospectively examined the association of dietary glycemic index (GI) and glycemic load (GL) with T2D risk. Design: We prospectively followed 74,248 women from the Nurses’ Health Study (1984–2008), 90,411 women from the Nurses’ Health Study II (1991–2009), and 40,498 men from the Health Professionals Follow-Up Study (1986–2008) who were free of diabetes, cardiovascular disease, and cancer at baseline. Diet was assessed by using a validated questionnaire and updated every 4 y. We also conducted an updated meta-analysis, including results from our 3 cohorts and other studies. Results: During 3,800,618 person-years of follow-up, we documented 15,027 cases of incident T2D. In pooled multivariable analyses, those in the highest quintile of energy-adjusted GI had a 33% higher risk (95% CI: 26%, 41%) of T2D than those in the lowest quintile. Participants in the highest quintile of energy-adjusted GL had a 10% higher risk (95% CI: 2%, 18%) of T2D. Participants who consumed a combination diet that was high in GI or GL and low in cereal fiber had an ∼50% higher risk of T2D. In the updated meta-analysis, the summary RRs (95% CIs) comparing the highest with the lowest categories of GI and GL were 1.19 (1.14, 1.24) and 1.13 (1.08, 1.17), respectively. Conclusion: The updated analyses from our 3 cohorts and meta-analyses provide further evidence that higher dietary GI and GL are associated with increased risk of T2D. PMID:24787496

Developing and validating a novel metabolic tumor volume risk stratification system for supplementing non-small cell lung cancer staging.

PubMed

Pu, Yonglin; Zhang, James X; Liu, Haiyan; Appelbaum, Daniel; Meng, Jianfeng; Penney, Bill C

2018-06-07

We hypothesized that whole-body metabolic tumor volume (MTVwb) could be used to supplement non-small cell lung cancer (NSCLC) staging due to its independent prognostic value. The goal of this study was to develop and validate a novel MTVwb risk stratification system to supplement NSCLC staging. We performed an IRB-approved retrospective review of 935 patients with NSCLC and FDG-avid tumor divided into modeling and validation cohorts based on the type of PET/CT scanner used for imaging. In addition, sensitivity analysis was conducted by dividing the patient population into two randomized cohorts. Cox regression and Kaplan-Meier survival analyses were performed to determine the prognostic value of the MTVwb risk stratification system. The cut-off values (10.0, 53.4 and 155.0 mL) between the MTVwb quartiles of the modeling cohort were applied to both the modeling and validation cohorts to determine each patient's MTVwb risk stratum. The survival analyses showed that a lower MTVwb risk stratum was associated with better overall survival (all p < 0.01), independent of TNM stage together with other clinical prognostic factors, and the discriminatory power of the MTVwb risk stratification system, as measured by Gönen and Heller's concordance index, was not significantly different from that of TNM stage in both cohorts. Also, the prognostic value of the MTVwb risk stratum was robust in the two randomized cohorts. The discordance rate between the MTVwb risk stratum and TNM stage or substage was 45.1% in the modeling cohort and 50.3% in the validation cohort. This study developed and validated a novel MTVwb risk stratification system, which has prognostic value independent of the TNM stage and other clinical prognostic factors in NSCLC, suggesting that it could be used for further NSCLC pretreatment assessment and for refining treatment decisions in individual patients.

Validating Facial Aesthetic Surgery Results with the FACE-Q.

PubMed

Kappos, Elisabeth A; Temp, Mathias; Schaefer, Dirk J; Haug, Martin; Kalbermatten, Daniel F; Toth, Bryant A

2017-04-01

In aesthetic clinical practice, surgical outcome is best measured by patient satisfaction and quality of life. For many years, there has been a lack of validated questionnaires. Recently, the FACE-Q was introduced, and the authors present the largest series of face-lift patients evaluated by the FACE-Q with the longest follow-up to date. Two hundred consecutive patients were identified who underwent high-superficial musculoaponeurotic system face lifts, with or without additional facial rejuvenation procedures, between January of 2005 and January of 2015. Patients were sent eight FACE-Q scales and were asked to answer questions with regard to their satisfaction. Rank analysis of covariance was used to compare different subgroups. The response rate was 38 percent. Combination of face lift with other procedures resulted in higher satisfaction than face lift alone (p < 0.05). Patients who underwent lipofilling as part of their face lift showed higher satisfaction than patients without lipofilling in three subscales (p < 0.05). Facial rejuvenation surgery, combining a high-superficial musculoaponeurotic system face lift with lipofilling and/or other facial rejuvenation procedures, resulted in a high level of patient satisfaction. The authors recommend the implementation of the FACE-Q by physicians involved in aesthetic facial surgery, to validate their clinical outcomes from a patient's perspective.

A new responder criterion (relative effect per patient (REPP) > 0.2) externally validated in a large total hip replacement multicenter cohort (EUROHIP).

PubMed

Huber, J; Hüsler, J; Dieppe, P; Günther, K P; Dreinhöfer, K; Judge, A

2016-03-01

To validate a new method to identify responders (relative effect per patient (REPP) >0.2) using the OMERACT-OARSI criteria as gold standard in a large multicentre sample. The REPP ([score before - after treatment]/score before treatment) was calculated for 845 patients of a large multicenter European cohort study for THR. The patients with a REPP >0.2 were defined as responders. The responder rate was compared to the gold standard (OMERACT-OARSI criteria) using receiver operator characteristic (ROC) curve analysis for sensitivity, specificity and percentage of appropriately classified patients. With the criterion REPP>0.2 85.4% of the patients were classified as responders, applying the OARSI-OMERACT criteria 85.7%. The new method had 98.8% sensitivity, 94.2% specificity and 98.1% of the patients were correctly classified compared to the gold standard. The external validation showed a high sensitivity and also specificity of a new criterion to identify a responder compared to the gold standard method. It is simple and has no uncertainties due to a single classification criterion. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Red meat consumption and mortality: results from 2 prospective cohort studies.

PubMed

Pan, An; Sun, Qi; Bernstein, Adam M; Schulze, Matthias B; Manson, JoAnn E; Stampfer, Meir J; Willett, Walter C; Hu, Frank B

2012-04-09

Red meat consumption has been associated with an increased risk of chronic diseases. However, its relationship with mortality remains uncertain. We prospectively observed 37 698 men from the Health Professionals Follow-up Study (1986-2008) and 83 644 women from the Nurses' Health Study (1980-2008) who were free of cardiovascular disease (CVD) and cancer at baseline. Diet was assessed by validated food frequency questionnaires and updated every 4 years. We documented 23 926 deaths (including 5910 CVD and 9464 cancer deaths) during 2.96 million person-years of follow-up. After multivariate adjustment for major lifestyle and dietary risk factors, the pooled hazard ratio (HR) (95% CI) of total mortality for a 1-serving-per-day increase was 1.13 (1.07-1.20) for unprocessed red meat and 1.20 (1.15-1.24) for processed red meat. The corresponding HRs (95% CIs) were 1.18 (1.13-1.23) and 1.21 (1.13-1.31) for CVD mortality and 1.10 (1.06-1.14) and 1.16 (1.09-1.23) for cancer mortality. We estimated that substitutions of 1 serving per day of other foods (including fish, poultry, nuts, legumes, low-fat dairy, and whole grains) for 1 serving per day of red meat were associated with a 7% to 19% lower mortality risk. We also estimated that 9.3% of deaths in men and 7.6% in women in these cohorts could be prevented at the end of follow-up if all the individuals consumed fewer than 0.5 servings per day (approximately 42 g/d) of red meat. Red meat consumption is associated with an increased risk of total, CVD, and cancer mortality. Substitution of other healthy protein sources for red meat is associated with a lower mortality risk.

Hypothesis-Free Search for Connections between Birth Month and Disease Prevalence in Large, Geographically Varied Cohorts

PubMed Central

Borsi, John P.

2016-01-01

We have sought to replicate and extend the Season-wide Association Study (SeaWAS) of Boland, et al.1 in identifying birth month-disease associations from electronic health records (EHRs). We used methodology similar to that implemented by Boland on three geographically distinct cohorts, for a total of 11.8 million individuals derived from multiple data sources. We were able to identify eleven out of sixteen literature-supported birth month associations as compared to seven of sixteen for SeaWAS. Of the nine novel cardiovascular birth month associations discovered by SeaWAS, we were able to replicate four. None of the novel non-cardiovascular associations discovered by SeaWAS emerged as significant relations in our study. We identified thirty birth month disease associations not previously reported; of those, only six associations were validated in more than one cohort. These results suggest that differences in cohort composition and location can cause consequential variation in results of hypothesis-free searches. PMID:28269826

The validity of student tutors' judgments in early detection of struggling in medical school. A prospective cohort study.

PubMed

O'Neill, Lotte Dyhrberg; Morcke, Anne Mette; Eika, Berit

2016-12-01

Early identification and support of strugglers in medical education is generally recommended in the research literature, though very little evidence of the diagnostic qualities of early teacher judgments in medical education currently exists. The aim of this study was to examine the validity of early diagnosis of struggling in medical school based on informal teacher judgements of in-class behavior. The study design was a prospective cohort study and the outcomes/truth criteria were anatomy failure and medical school drop out. Six weeks into an anatomy course, student tutors attempted to identify medical students, who they reckoned would fail the anatomy course or drop out, based on their everyday experiences with students in a large group educational setting. In addition, they were asked to describe the indicators of struggling they observed. Sixteen student tutors evaluated 429 medical students for signs of struggling. By week six, the student tutors were able to detect approximately 1/4-1/3 of the students who eventually failed or dropped out, and for ¾ of the strugglers they identified, they were correct in their judgments. Informal student tutor's judgements showed incremental validity for both outcomes when controlling for grades obtained in preceeding exams. Lack of participation, lack of commitment, poor academic performance, poor social interactions and general signs of distress were the main indicators of struggling identified. Teachers' informal judgements of in-class behavior may be an untapped source of information in the early identification of struggling medical students with added value above and beyond formal testing.

Validity of the estimates of oral cholera vaccine effectiveness derived from the test-negative design.

PubMed

Ali, Mohammad; You, Young Ae; Sur, Dipika; Kanungo, Suman; Kim, Deok Ryun; Deen, Jacqueline; Lopez, Anna Lena; Wierzba, Thomas F; Bhattacharya, Sujit K; Clemens, John D

2016-01-20

The test-negative design (TND) has emerged as a simple method for evaluating vaccine effectiveness (VE). Its utility for evaluating oral cholera vaccine (OCV) effectiveness is unknown. We examined this method's validity in assessing OCV effectiveness by comparing the results of TND analyses with those of conventional cohort analyses. Randomized controlled trials of OCV were conducted in Matlab (Bangladesh) and Kolkata (India), and an observational cohort design was used in Zanzibar (Tanzania). For all three studies, VE using the TND was estimated from the odds ratio (OR) relating vaccination status to fecal test status (Vibrio cholerae O1 positive or negative) among diarrheal patients enrolled during surveillance (VE= (1-OR)×100%). In cohort analyses of these studies, we employed the Cox proportional hazard model for estimating VE (=1-hazard ratio)×100%). OCV effectiveness estimates obtained using the TND (Matlab: 51%, 95% CI:37-62%; Kolkata: 67%, 95% CI:57-75%) were similar to the cohort analyses of these RCTs (Matlab: 52%, 95% CI:43-60% and Kolkata: 66%, 95% CI:55-74%). The TND VE estimate for the Zanzibar data was 94% (95% CI:84-98%) compared with 82% (95% CI:58-93%) in the cohort analysis. After adjusting for residual confounding in the cohort analysis of the Zanzibar study, using a bias indicator condition, we observed almost no difference in the two estimates. Our findings suggest that the TND is a valid approach for evaluating OCV effectiveness in routine vaccination programs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cohort Profile: Antiretroviral Therapy Cohort Collaboration (ART-CC)

PubMed Central

May, Margaret T; Ingle, Suzanne M; Costagliola, Dominique; Justice, Amy C; de Wolf, Frank; Cavassini, Matthias; D’Arminio Monforte, Antonella; Casabona, Jordi; Hogg, Robert S; Mocroft, Amanda; Lampe, Fiona C; Dabis, François; Fätkenheuer, Gerd; Sterling, Timothy R; del Amo, Julia; Gill, M John; Crane, Heidi M; Saag, Michael S; Guest, Jodie; Brodt, Hans-Reinhard; Sterne, Jonathan AC

2014-01-01

The advent of effective combination antiretroviral therapy (ART) in 1996 resulted in fewer patients experiencing clinical events, so that some prognostic analyses of individual cohort studies of human immunodeficiency virus-infected individuals had low statistical power. Because of this, the Antiretroviral Therapy Cohort Collaboration (ART-CC) of HIV cohort studies in Europe and North America was established in 2000, with the aim of studying the prognosis for clinical events in acquired immune deficiency syndrome (AIDS) and the mortality of adult patients treated for HIV-1 infection. In 2002, the ART-CC collected data on more than 12,000 patients in 13 cohorts who had begun combination ART between 1995 and 2001. Subsequent updates took place in 2004, 2006, 2008, and 2010. The ART-CC data base now includes data on more than 70 000 patients participating in 19 cohorts who began treatment before the end of 2009. Data are collected on patient demographics (e.g. sex, age, assumed transmission group, race/ethnicity, geographical origin), HIV biomarkers (e.g. CD4 cell count, plasma viral load of HIV-1), ART regimen, dates and types of AIDS events, and dates and causes of death. In recent years, additional data on co-infections such as hepatitis C; risk factors such as smoking, alcohol and drug use; non-HIV biomarkers such as haemoglobin and liver enzymes; and adherence to ART have been collected whenever available. The data remain the property of the contributing cohorts, whose representatives manage the ART-CC via the steering committee of the Collaboration. External collaboration is welcomed. Details of contacts are given on the ART-CC website (www.art-cohort-collaboration.org). PMID:23599235

Relative validity of an FFQ for pre-school children in the mother-child 'Rhea' birth cohort in Crete, Greece.

PubMed

Leventakou, Vasiliki; Georgiou, Vaggelis; Chatzi, Leda; Sarri, Katerina

2015-02-01

To examine the relative validity of an FFQ based on parental report for pre-school children in the mother-child 'Rhea' birth cohort. The children's mothers completed an FFQ that referred to the children's dietary intake for the previous year by telephone interview. Mothers completed also three food records, two on weekdays and one on a weekend day. Spearman correlation coefficients were calculated for the energy-adjusted values. Weighted kappa statistics (κ(w)) and the Bland-Altman technique were used to test the degree of agreement between the two dietary methods. Heraklion, Crete, Greece, 2011-2012. A total of ninety-nine mothers (corresponding to fifty-one boys and forty-eight girls) participated in the validation study. The mean and median values of all food group and nutrient intakes did not differ significantly between the two dietary methods. Overall, fair agreement was observed between the FFQ and the food records for ranking participants based on their intake, with κ(w) ranging from 0·21 to 0·40 for most foods and nutrients. On average, 88 % of participants were classified into the same or adjacent tertiles for nutrient and food group intakes by both dietary methods. The degree of agreement was also confirmed by the visual examination of the Bland-Altman plots. The study indicates that the Rhea 4 years FFQ is a relatively accurate tool for assessing habitual food group and nutrient intakes among pre-school children in Crete, Greece.

Development and validation of a rebinner with rigid motion correction for the Siemens PET-MR scanner: Application to a large cohort of [11C]-PIB scans.

PubMed

Reilhac, Anthonin; Merida, Ines; Irace, Zacharie; Stephenson, Mary; Weekes, Ashley; Chen, Christopher; Totman, John; Townsend, David W; Fayad, Hadi; Costes, Nicolas

2018-04-13

Objective: Head motion occuring during brain PET studies leads to image blurring and to bias in measured local quantities. Our first objective was to implement an accurate list-mode-based rigid motion correction method for PET data acquired with the mMR synchronous Positron Emission Tomography/Magnetic Resonance (PET/MR) scanner. Our second objective was to optimize the correction for [ 11 C]-PIB scans using simulated and actual data with well-controlled motions. Results: An efficient list-mode based motion correction approach has been implemented, fully optimized and validated using simulated as well as actual PET data. The average spatial resolution loss induced by inaccuracies in motion parameter estimates as well as by the rebinning process was estimated to correspond to a 1 mm increase in Full Width Half Maximum (FWHM) with motion parameters estimated directly from the PET data with a temporal frequency of 20 secs. The results show that it can be safely applied to the [ 11 C]-PIB scans, allowing almost complete removal of motion induced artifacts.The application of the correction method on a large cohort of 11C-PIB scans led to the following observations: i) more than 21% of the scans were affected by a motion greater than 10 mm (39% for subjects with Mini-Mental State Examination -MMSE scores below 20) and ii), the correction led to quantitative changes in Alzheimer-specific cortical regions of up to 30%. Conclusion: The rebinner allows an accurate motion correction at a cost of minimal resolution reduction. The application of the correction to a large cohort of [ 11 C]-PIB scans confirmed the necessity to systematically correct for motion for quantitative results. Copyright © 2018 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Evaluating the reliability, validity, acceptability, and practicality of SMS text messaging as a tool to collect research data: results from the Feeding Your Baby project

PubMed Central

Donnan, Peter T; Symon, Andrew G; Kellett, Gillian; Monteith-Hodge, Ewa; Rauchhaus, Petra; Wyatt, Jeremy C

2012-01-01

Objective To test the reliability, validity, acceptability, and practicality of short message service (SMS) messaging for collection of research data. Materials and methods The studies were carried out in a cohort of recently delivered women in Tayside, Scotland, UK, who were asked about their current infant feeding method and future feeding plans. Reliability was assessed by comparison of their responses to two SMS messages sent 1 day apart. Validity was assessed by comparison of their responses to text questions and the same question administered by phone 1 day later, by comparison with the same data collected from other sources, and by correlation with other related measures. Acceptability was evaluated using quantitative and qualitative questions, and practicality by analysis of a researcher log. Results Reliability of the factual SMS message gave perfect agreement. Reliabilities for the numerical question were reasonable, with κ between 0.76 (95% CI 0.56 to 0.96) and 0.80 (95% CI 0.59 to 1.00). Validity for data compared with that collected by phone within 24 h (κ =0.92 (95% CI 0.84 to 1.00)) and with health visitor data (κ =0.85 (95% CI 0.73 to 0.97)) was excellent. Correlation validity between the text responses and other related demographic and clinical measures was as expected. Participants found the method a convenient and acceptable way of providing data. For researchers, SMS text messaging provided an easy and functional method of gathering a large volume of data. Conclusion In this sample and for these questions, SMS was a reliable and valid method for capturing research data. PMID:22539081

Changes in Waist Circumference among German Adults over Time – Compiling Results of Seven Prospective Cohort Studies

PubMed Central

Haftenberger, Marjolein; Mensink, Gert B.M.; Vogt, Susanne; Thorand, Barbara; Peters, Annette; Herzog, Beatrice; Hartwig, Saskia; Greiser, Karin Halina; Ittermann, Till; Schipf, Sabine; Völzke, Henry; Merz, Benedikt; Nöthlings, Ute; Koch, Manja; Neamat-Allah, Jasmine; Katzke, Verena; Kaaks, Rudolf; Boeing, Heiner; Bachlechner, Ursula; Scheidt-Nave, Christa; Schienkiewitz, Anja

2016-01-01

Aim This study aims to quantify longitudinal changes in waist circumference (WC) among adults aged 45–64 years in Germany. Methods Data of 15,444 men and 17,207 women from one nationwide and six regional prospective German cohort studies were analyzed. The sex-specific mean change in WC per year of follow-up was assessed for each study separately. Findings from the cohort-by-cohort analysis were combined by applying meta-analytic methods. Progression to central obesity (WC ≥ 102 cm in men and ≥ 88 cm in women) within a standardized period of 10 years was described for each study. Results The estimated mean change in WC per year of follow-up for all cohorts combined was 0.53 (95s% confidence interval 0.29–0.76) cm/year for men and 0.63 (0.48–0.77) cm/year for women, but varied between the included studies. Within 10 years, about 20s% of individuals with low WC (<94 cm in men; <80 cm in women) and about 50s% of individuals with intermediate WC (94–102 cm in men; 80–88 cm in women) progressed to central obesity. Conclusion The increase in mean WC with aging along with a profound increase of central adiposity is obviously and may have several adverse health effects. Obesity prevention programs should also focus on abdominal obesity. PMID:27701174

Prediction of overall survival for metastatic pancreatic cancer: Development and validation of a prognostic nomogram with data from open clinical trial and real-world study.

PubMed

Hang, Junjie; Wu, Lixia; Zhu, Lina; Sun, Zhiqiang; Wang, Ge; Pan, Jingjing; Zheng, Suhua; Xu, Kequn; Du, Jiadi; Jiang, Hua

2018-06-01

It is necessary to develop prognostic tools of metastatic pancreatic cancer (MPC) for optimizing therapeutic strategies. Thus, we tried to develop and validate a prognostic nomogram of MPC. Data from 3 clinical trials (NCT00844649, NCT01124786, and NCT00574275) and 133 Chinese MPC patients were used for analysis. The former 2 trials were taken as the training cohort while NCT00574275 was used as the validation cohort. In addition, 133 MPC patients treated in China were taken as the testing cohort. Cox regression model was used to investigate prognostic factors in the training cohort. With these factors, we established a nomogram and verified it by Harrell's concordance index (C-index) and calibration plots. Furthermore, the nomogram was externally validated in the validation cohort and testing cohort. In the training cohort (n = 445), performance status, liver metastasis, Carbohydrate antigen 19-9 (CA19-9) log-value, absolute neutrophil count (ANC), and albumin were independent prognostic factors for overall survival (OS). A nomogram was established with these factors to predict OS and survival probabilities. The nomogram showed an acceptable discrimination ability (C-index: .683) and good calibration, and was further externally validated in the validation cohort (n = 273, C-index: .699) and testing cohort (n = 133, C-index: .653).The nomogram total points (NTP) had the potential to stratify patients into 3-risk groups with median OS of 11.7, 7.0 and 3.7 months (P < .001), respectively. In conclusion, the prognostic nomogram with NTP can predict OS for patients with MPC with considerable accuracy. © 2018 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Validation of Six Short and Ultra-short Screening Instruments for Depression for People Living with HIV in Ontario: Results from the Ontario HIV Treatment Network Cohort Study

PubMed Central

Choi, Stephanie K. Y.; Boyle, Eleanor; Burchell, Ann N.; Gardner, Sandra; Collins, Evan; Grootendorst, Paul; Rourke, Sean B.

2015-01-01

Objective Major depression affects up to half of people living with HIV. However, among HIV-positive patients, depression goes unrecognized 60–70% of the time in non-psychiatric settings. We sought to evaluate three screening instruments and their short forms to facilitate the recognition of current depression in HIV-positive patients attending HIV specialty care clinics in Ontario. Methods A multi-centre validation study was conducted in Ontario to examine the validity and accuracy of three instruments (the Center for Epidemiologic Depression Scale [CESD20], the Kessler Psychological Distress Scale [K10], and the Patient Health Questionnaire depression scale [PHQ9]) and their short forms (CESD10, K6, and PHQ2) in diagnosing current major depression among 190 HIV-positive patients in Ontario. Results from the three instruments and their short forms were compared to results from the gold standard measured by Mini International Neuropsychiatric Interview (the “M.I.N.I.”). Results Overall, the three instruments identified depression with excellent accuracy and validity (area under the curve [AUC]>0.9) and good reliability (Kappa statistics: 0.71–0.79; Cronbach’s alpha: 0.87–0.93). We did not find that the AUCs differed in instrument pairs (p-value>0.09), or between the instruments and their short forms (p-value>0.3). Except for the PHQ2, the instruments showed good-to-excellent sensitivity (0.86–1.0) and specificity (0.81–0.87), excellent negative predictive value (>0.90), and moderate positive predictive value (0.49–0.58) at their optimal cut-points. Conclusion Among people in HIV care in Ontario, Canada, the three instruments and their short forms performed equally well and accurately. When further in-depth assessments become available, shorter instruments might find greater clinical acceptance. This could lead to clinical benefits in fast-paced speciality HIV care settings and better management of depression in HIV-positive patients. PMID:26566285

Development and validation of multivariable predictive model for thromboembolic events in lymphoma patients.

PubMed

Antic, Darko; Milic, Natasa; Nikolovski, Srdjan; Todorovic, Milena; Bila, Jelena; Djurdjevic, Predrag; Andjelic, Bosko; Djurasinovic, Vladislava; Sretenovic, Aleksandra; Vukovic, Vojin; Jelicic, Jelena; Hayman, Suzanne; Mihaljevic, Biljana

2016-10-01

Lymphoma patients are at increased risk of thromboembolic events but thromboprophylaxis in these patients is largely underused. We sought to develop and validate a simple model, based on individual clinical and laboratory patient characteristics that would designate lymphoma patients at risk for thromboembolic event. The study population included 1,820 lymphoma patients who were treated in the Lymphoma Departments at the Clinics of Hematology, Clinical Center of Serbia and Clinical Center Kragujevac. The model was developed using data from a derivation cohort (n = 1,236), and further assessed in the validation cohort (n = 584). Sixty-five patients (5.3%) in the derivation cohort and 34 (5.8%) patients in the validation cohort developed thromboembolic events. The variables independently associated with risk for thromboembolism were: previous venous and/or arterial events, mediastinal involvement, BMI>30 kg/m(2) , reduced mobility, extranodal localization, development of neutropenia and hemoglobin level < 100g/L. Based on the risk model score, the population was divided into the following risk categories: low (score 0-1), intermediate (score 2-3), and high (score >3). For patients classified at risk (intermediate and high-risk scores), the model produced negative predictive value of 98.5%, positive predictive value of 25.1%, sensitivity of 75.4%, and specificity of 87.5%. A high-risk score had positive predictive value of 65.2%. The diagnostic performance measures retained similar values in the validation cohort. Developed prognostic Thrombosis Lymphoma - ThroLy score is more specific for lymphoma patients than any other available score targeting thrombosis in cancer patients. Am. J. Hematol. 91:1014-1019, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Derivation and External Validation of Prediction Models for Advanced Chronic Kidney Disease Following Acute Kidney Injury.

PubMed

James, Matthew T; Pannu, Neesh; Hemmelgarn, Brenda R; Austin, Peter C; Tan, Zhi; McArthur, Eric; Manns, Braden J; Tonelli, Marcello; Wald, Ron; Quinn, Robert R; Ravani, Pietro; Garg, Amit X

2017-11-14

Some patients will develop chronic kidney disease after a hospitalization with acute kidney injury; however, no risk-prediction tools have been developed to identify high-risk patients requiring follow-up. To derive and validate predictive models for progression of acute kidney injury to advanced chronic kidney disease. Data from 2 population-based cohorts of patients with a prehospitalization estimated glomerular filtration rate (eGFR) of more than 45 mL/min/1.73 m2 and who had survived hospitalization with acute kidney injury (defined by a serum creatinine increase during hospitalization > 0.3 mg/dL or > 50% of their prehospitalization baseline), were used to derive and validate multivariable prediction models. The risk models were derived from 9973 patients hospitalized in Alberta, Canada (April 2004-March 2014, with follow-up to March 2015). The risk models were externally validated with data from a cohort of 2761 patients hospitalized in Ontario, Canada (June 2004-March 2012, with follow-up to March 2013). Demographic, laboratory, and comorbidity variables measured prior to discharge. Advanced chronic kidney disease was defined by a sustained reduction in eGFR less than 30 mL/min/1.73 m2 for at least 3 months during the year after discharge. All participants were followed up for up to 1 year. The participants (mean [SD] age, 66 [15] years in the derivation and internal validation cohorts and 69 [11] years in the external validation cohort; 40%-43% women per cohort) had a mean (SD) baseline serum creatinine level of 1.0 (0.2) mg/dL and more than 20% had stage 2 or 3 acute kidney injury. Advanced chronic kidney disease developed in 408 (2.7%) of 9973 patients in the derivation cohort and 62 (2.2%) of 2761 patients in the external validation cohort. In the derivation cohort, 6 variables were independently associated with the outcome: older age, female sex, higher baseline serum creatinine value, albuminuria, greater severity of acute kidney injury, and higher

Lessons Learned From Methodological Validation Research in E-Epidemiology

PubMed Central

Assmann, Karen; Andreeva, Valentina; Castetbon, Katia; Méjean, Caroline; Touvier, Mathilde; Salanave, Benoît; Deschamps, Valérie; Péneau, Sandrine; Fezeu, Léopold; Julia, Chantal; Allès, Benjamin; Galan, Pilar; Hercberg, Serge

2016-01-01

Background Traditional epidemiological research methods exhibit limitations leading to high logistics, human, and financial burden. The continued development of innovative digital tools has the potential to overcome many of the existing methodological issues. Nonetheless, Web-based studies remain relatively uncommon, partly due to persistent concerns about validity and generalizability. Objective The objective of this viewpoint is to summarize findings from methodological studies carried out in the NutriNet-Santé study, a French Web-based cohort study. Methods On the basis of the previous findings from the NutriNet-Santé e-cohort (>150,000 participants are currently included), we synthesized e-epidemiological knowledge on sample representativeness, advantageous recruitment strategies, and data quality. Results Overall, the reported findings support the usefulness of Web-based studies in overcoming common methodological deficiencies in epidemiological research, in particular with regard to data quality (eg, the concordance for body mass index [BMI] classification was 93%), reduced social desirability bias, and access to a wide range of participant profiles, including the hard-to-reach subgroups such as young (12.30% [15,118/122,912], <25 years) and old people (6.60% [8112/122,912], ≥65 years), unemployed or homemaker (12.60% [15,487/122,912]), and low educated (38.50% [47,312/122,912]) people. However, some selection bias remained (78.00% (95,871/122,912) of the participants were women, and 61.50% (75,590/122,912) had postsecondary education), which is an inherent aspect of cohort study inclusion; other specific types of bias may also have occurred. Conclusions Given the rapidly growing access to the Internet across social strata, the recruitment of participants with diverse socioeconomic profiles and health risk exposures was highly feasible. Continued efforts concerning the identification of specific biases in e-cohorts and the collection of comprehensive and

Nordic registry-based cohort studies: Possibilities and pitfalls when combining Nordic registry data.

PubMed

Maret-Ouda, John; Tao, Wenjing; Wahlin, Karl; Lagergren, Jesper

2017-07-01

All five Nordic countries (Denmark, Finland, Iceland, Norway and Sweden) have nationwide registries with similar data structure and validity, as well as personal identity numbers enabling linkage between registries. These resources provide opportunities for medical research that is based on large registry-based cohort studies with long and complete follow-up. This review describes practical aspects, opportunities and challenges encountered when setting up all-Nordic registry-based cohort studies. Relevant articles describing registries often used for medical research in the Nordic countries were retrieved. Further, our experiences of conducting this type of study, including planning, acquiring permissions, data retrieval and data cleaning and handling, and the possibilities and challenges we have encountered are described. Combining data from the Nordic countries makes it possible to create large and powerful cohorts. The main challenges include obtaining all permissions within each country, usually in the local language, and retrieving the data. These challenges emphasise the importance of having experienced collaborators within each country. Following the acquisition of data, data management requires the understanding of the differences between the variables to be used in the various countries. A concern is the long time required between initiation and completion. Nationwide Nordic registries can be combined into cohorts with high validity and statistical power, but the considerable expertise, workload and time required to complete such cohorts should not be underestimated.

Rationale, design, and preliminary results of the Quebec Warfarin Cohort Study.

PubMed

Perreault, Sylvie; Shahabi, Payman; Côté, Robert; Dumas, Stéphanie; Rouleau-Mailloux, Étienne; Feroz Zada, Yassamin; Provost, Sylvie; Mongrain, Ian; Dorais, Marc; Huynh, Thao; Kouz, Simon; Diaz, Ariel; Blostein, Mark; de Denus, Simon; Turgeon, Jacques; Ginsberg, Jeffrey; Lelorier, Jacques; Lalonde, Lyne; Busque, Lambert; Kassis, Jeannine; Talajic, Mario; Tardif, Jean-Claude; Dubé, Marie-Pierre

2018-05-01

Over- and undercoagulation with warfarin are associated with hemorrhagic and thromboembolic events, respectively. Genetic and clinical factors affect warfarin response, and the causes of this variability remain unclear. We present descriptive statistics and test for predictors of poor anticoagulation control. The Quebec Warfarin Cohort (QWC) comprises 1059 new warfarin users, with prospective follow-up using telephone questionnaires every 3 months for 1 year, and using healthcare administrative databases (RAMQ and Med-Echo) for 5 years prior to cohort entry and up to 10 years following active patient participation. Genetic material was collected, and genotyping of CYP2C9 and VKORC1 genes was conducted. Measured outcomes included the percentage of time patients spent within therapeutic range, anticoagulation control, warfarin dose, bleeding, and thromboembolic events. We report baseline characteristics and outcomes after 1 year of follow-up. Poor anticoagulation control was defined as time in therapeutic range <60% in the 3- to 12-month interval. Participants had a mean age of 71 years, and 62% were men. The most common indication for warfarin was atrial fibrillation (87%). Mean time in therapeutic range was 56% (±25%) in the 3 months following warfarin initiation, and 70% (±21%) in the 3- to 12-month interval. During follow-up, the rate of stroke or systemic embolism was 1.8 events per 100 person-years; for major bleeding events, 3.3 events per 100 person-years. Independent predictors of poor anticoagulation control were chronic kidney disease, heart failure, dyslipidemia, and age. The QWC represents a good research cohort to investigate clinical and genetic factors in a warfarin-anticoagulated population. © 2018 Wiley Periodicals, Inc.

Development and external validation of a prostate health index-based nomogram for predicting prostate cancer

PubMed Central

Zhu, Yao; Han, Cheng-Tao; Zhang, Gui-Ming; Liu, Fang; Ding, Qiang; Xu, Jian-Feng; Vidal, Adriana C.; Freedland, Stephen J.; Ng, Chi-Fai; Ye, Ding-Wei

2015-01-01

To develop and externally validate a prostate health index (PHI)-based nomogram for predicting the presence of prostate cancer (PCa) at biopsy in Chinese men with prostate-specific antigen 4–10 ng/mL and normal digital rectal examination (DRE). 347 men were recruited from two hospitals between 2012 and 2014 to develop a PHI-based nomogram to predict PCa. To validate these results, we used a separate cohort of 230 men recruited at another center between 2008 and 2013. Receiver operator curves (ROC) were used to assess the ability to predict PCa. A nomogram was derived from the multivariable logistic regression model and its accuracy was assessed by the area under the ROC (AUC). PHI achieved the highest AUC of 0.839 in the development cohort compared to the other predictors (p < 0.001). Including age and prostate volume, a PHI-based nomogram was constructed and rendered an AUC of 0.877 (95% CI 0.813–0.938). The AUC of the nomogram in the validation cohort was 0.786 (95% CI 0.678–0.894). In clinical effectiveness analyses, the PHI-based nomogram reduced unnecessary biopsies from 42.6% to 27% using a 5% threshold risk of PCa to avoid biopsy with no increase in the number of missed cases relative to conventional biopsy decision. PMID:26471350

Validation of spatial variability in downscaling results from the VALUE perfect predictor experiment

NASA Astrophysics Data System (ADS)

Widmann, Martin; Bedia, Joaquin; Gutiérrez, Jose Manuel; Maraun, Douglas; Huth, Radan; Fischer, Andreas; Keller, Denise; Hertig, Elke; Vrac, Mathieu; Wibig, Joanna; Pagé, Christian; Cardoso, Rita M.; Soares, Pedro MM; Bosshard, Thomas; Casado, Maria Jesus; Ramos, Petra

2016-04-01

VALUE is an open European network to validate and compare downscaling methods for climate change research. Within VALUE a systematic validation framework to enable the assessment and comparison of both dynamical and statistical downscaling methods has been developed. In the first validation experiment the downscaling methods are validated in a setup with perfect predictors taken from the ERA-interim reanalysis for the period 1997 - 2008. This allows to investigate the isolated skill of downscaling methods without further error contributions from the large-scale predictors. One aspect of the validation is the representation of spatial variability. As part of the VALUE validation we have compared various properties of the spatial variability of downscaled daily temperature and precipitation with the corresponding properties in observations. We have used two test validation datasets, one European-wide set of 86 stations, and one higher-density network of 50 stations in Germany. Here we present results based on three approaches, namely the analysis of i.) correlation matrices, ii.) pairwise joint threshold exceedances, and iii.) regions of similar variability. We summarise the information contained in correlation matrices by calculating the dependence of the correlations on distance and deriving decorrelation lengths, as well as by determining the independent degrees of freedom. Probabilities for joint threshold exceedances and (where appropriate) non-exceedances are calculated for various user-relevant thresholds related for instance to extreme precipitation or frost and heat days. The dependence of these probabilities on distance is again characterised by calculating typical length scales that separate dependent from independent exceedances. Regionalisation is based on rotated Principal Component Analysis. The results indicate which downscaling methods are preferable if the dependency of variability at different locations is relevant for the user.

Validation of Six Short and Ultra-short Screening Instruments for Depression for People Living with HIV in Ontario: Results from the Ontario HIV Treatment Network Cohort Study.

PubMed

Choi, Stephanie K Y; Boyle, Eleanor; Burchell, Ann N; Gardner, Sandra; Collins, Evan; Grootendorst, Paul; Rourke, Sean B

2015-01-01

Major depression affects up to half of people living with HIV. However, among HIV-positive patients, depression goes unrecognized 60-70% of the time in non-psychiatric settings. We sought to evaluate three screening instruments and their short forms to facilitate the recognition of current depression in HIV-positive patients attending HIV specialty care clinics in Ontario. A multi-centre validation study was conducted in Ontario to examine the validity and accuracy of three instruments (the Center for Epidemiologic Depression Scale [CESD20], the Kessler Psychological Distress Scale [K10], and the Patient Health Questionnaire depression scale [PHQ9]) and their short forms (CESD10, K6, and PHQ2) in diagnosing current major depression among 190 HIV-positive patients in Ontario. Results from the three instruments and their short forms were compared to results from the gold standard measured by Mini International Neuropsychiatric Interview (the "M.I.N.I."). Overall, the three instruments identified depression with excellent accuracy and validity (area under the curve [AUC]>0.9) and good reliability (Kappa statistics: 0.71-0.79; Cronbach's alpha: 0.87-0.93). We did not find that the AUCs differed in instrument pairs (p-value>0.09), or between the instruments and their short forms (p-value>0.3). Except for the PHQ2, the instruments showed good-to-excellent sensitivity (0.86-1.0) and specificity (0.81-0.87), excellent negative predictive value (>0.90), and moderate positive predictive value (0.49-0.58) at their optimal cut-points. Among people in HIV care in Ontario, Canada, the three instruments and their short forms performed equally well and accurately. When further in-depth assessments become available, shorter instruments might find greater clinical acceptance. This could lead to clinical benefits in fast-paced speciality HIV care settings and better management of depression in HIV-positive patients.

Multicenter validation of a bedside antisaccade task as a measure of executive function

PubMed Central

Hellmuth, J.; Mirsky, J.; Heuer, H.W.; Matlin, A.; Jafari, A.; Garbutt, S.; Widmeyer, M.; Berhel, A.; Sinha, L.; Miller, B.L.; Kramer, J.H.

2012-01-01

Objective: To create and validate a simple, standardized version of the antisaccade (AS) task that requires no specialized equipment for use as a measure of executive function in multicenter clinical studies. Methods: The bedside AS (BAS) task consisted of 40 pseudorandomized AS trials presented on a laptop computer. BAS performance was compared with AS performance measured using an infrared eye tracker in normal elders (NE) and individuals with mild cognitive impairment (MCI) or dementia (n = 33). The neuropsychological domain specificity of the BAS was then determined in a cohort of NE, MCI, and dementia (n = 103) at UCSF, and the BAS was validated as a measure of executive function in a 6-center cohort (n = 397) of normal adults and patients with a variety of brain diseases. Results: Performance on the BAS and laboratory AS task was strongly correlated and BAS performance was most strongly associated with neuropsychological measures of executive function. Even after controlling for disease severity and processing speed, BAS performance was associated with multiple assessments of executive function, most strongly the informant-based Frontal Systems Behavior Scale. Conclusions: The BAS is a simple, valid measure of executive function in aging and neurologic disease. PMID:22573640

Cohort profile: Antiretroviral Therapy Cohort Collaboration (ART-CC).

PubMed

May, Margaret T; Ingle, Suzanne M; Costagliola, Dominique; Justice, Amy C; de Wolf, Frank; Cavassini, Matthias; D'Arminio Monforte, Antonella; Casabona, Jordi; Hogg, Robert S; Mocroft, Amanda; Lampe, Fiona C; Dabis, François; Fätkenheuer, Gerd; Sterling, Timothy R; del Amo, Julia; Gill, M John; Crane, Heidi M; Saag, Michael S; Guest, Jodie; Brodt, Hans-Reinhard; Sterne, Jonathan A C

2014-06-01

The advent of effective combination antiretroviral therapy (ART) in 1996 resulted in fewer patients experiencing clinical events, so that some prognostic analyses of individual cohort studies of human immunodeficiency virus-infected individuals had low statistical power. Because of this, the Antiretroviral Therapy Cohort Collaboration (ART-CC) of HIV cohort studies in Europe and North America was established in 2000, with the aim of studying the prognosis for clinical events in acquired immune deficiency syndrome (AIDS) and the mortality of adult patients treated for HIV-1 infection. In 2002, the ART-CC collected data on more than 12,000 patients in 13 cohorts who had begun combination ART between 1995 and 2001. Subsequent updates took place in 2004, 2006, 2008, and 2010. The ART-CC data base now includes data on more than 70,000 patients participating in 19 cohorts who began treatment before the end of 2009. Data are collected on patient demographics (e.g. sex, age, assumed transmission group, race/ethnicity, geographical origin), HIV biomarkers (e.g. CD4 cell count, plasma viral load of HIV-1), ART regimen, dates and types of AIDS events, and dates and causes of death. In recent years, additional data on co-infections such as hepatitis C; risk factors such as smoking, alcohol and drug use; non-HIV biomarkers such as haemoglobin and liver enzymes; and adherence to ART have been collected whenever available. The data remain the property of the contributing cohorts, whose representatives manage the ART-CC via the steering committee of the Collaboration. External collaboration is welcomed. Details of contacts are given on the ART-CC website (www.art-cohort-collaboration.org). Published by Oxford University Press on behalf of the International Epidemiological Association © The Author 2013; all rights reserved.

Cancer mortality risk among biology research workers in France: first results of two retrospective cohorts studies.

PubMed

Guseva Canu, Irina; Rogel, Agnès; Samson, Eric; Benhamou, Simone; Laplanche, Agnès; Tirmarche, Margot

2008-05-01

To investigate all-cause and cancer mortality of biological research laboratories workers of the French Atomic Energy Commission (CEA) and the National Institute of Health and Medical Research (INSERM). Two cohorts, bioCEA (N = 3,509) and bioINSERM (N = 4,966) were followed from 1968 to 1994 and 1980 to 1993, respectively. The mortality of each cohort was compared with that of the French population by computation of the standardized mortality ratio (SMR) with their 90% confidence interval (90% CI). Trend and heterogeneity tests were computed in order to study SMRs variation by job characteristics. In the bioCEA cohort individual dosimetry data being available, a trend test was also computed according to ionizing radiation cumulative dose. The SMRs were significantly below one in both cohorts for all-cause mortality (bioCEA: SMR = 0.52 [0.46-0.59], bioINSERM: SMR = 0.56 [0.46-0.67]) and for all-cancer mortality (bioCEA: SMR = 0.66 [0.54-0.80], bioINSERM: SMR = 0.55 [0.39-0.75]). There were some specific cancer sites for which the SMR was higher than 1, but not significantly. In the bioCEA cohort a positive trend was observed between ionizing radiation cumulative doses and all-cause as well as all-cancer SMRs. This study on two French cohorts of biological research workers found a favorable mortality pattern. These findings are consistent with recent publications. The positive trend of cancer mortality according to ionizing radiation exposure among bioCEA cohort needs to be confirmed with more precise assessment of exposures and information on individual risk factors.

Validation of self-reported information on dental caries in a birth cohort at 18 years of age.

PubMed

Silva, Alexandre Emidio Ribeiro; Menezes, Ana Maria Baptista; Assunção, Maria Cecília Formoso; Gonçalves, Helen; Demarco, Flávio Fernando; Vargas-Ferreira, Fabiana; Peres, Marco Aurélio

2014-01-01

Estimate the prevalence of dental caries based on clinical examinations and self-reports and compare differences in the prevalence and effect measures between the two methods among 18-year-olds belonging to a 1993 birth cohort in the city of Pelotas, Brazil. Data on self-reported caries, socio-demographic aspects and oral health behaviour were collected using a questionnaire administered to adolescents aged 18 years (n = 4041). Clinical caries was evaluated (n = 1014) by a dentist who had undergone training and calibration exercises. Prevalence rates of clinical and self-reported caries, sensitivity, specificity, positive and negative predictive values, absolute and relative bias, and inflation factors were calculated. Prevalence ratios of dental caries were estimated for each risk factor. The prevalence of clinical and self-reported caries (DMFT>1) was 66.5% (95%CI: 63.6%-69.3%) and 60.3% (95%CI: 58.8%-61.8%), respectively. Self-reports underestimated the prevalence of dental caries by 9.3% in comparison to clinical evaluations. The analysis of the validity of self-reports regarding the DMFT index indicated high sensitivity (81.8%; 95%CI: 78.7%-84.7%) and specificity (78.1%; 95%CI: 73.3%-82.4%) in relation to the gold standard (clinical evaluation). Both the clinical and self-reported evaluations were associated with gender, schooling and self-rated oral health. Clinical dental caries was associated with visits to the dentist in the previous year. Self-reported dental caries was associated with daily tooth brushing frequency. Based on the present findings, self-reported information on dental caries using the DMFT index requires further studies prior to its use in the analysis of risk factors, but is valid for population-based health surveys with the aim of planning and monitoring oral health actions directed at adolescents.

Validation Results for LEWICE 3.0

NASA Technical Reports Server (NTRS)

Wright, William B.

2005-01-01

A research project is underway at NASA Glenn to produce computer software that can accurately predict ice growth under any meteorological conditions for any aircraft surface. This report will present results from version 3.0 of this software, which is called LEWICE. This version differs from previous releases in that it incorporates additional thermal analysis capabilities, a pneumatic boot model, interfaces to computational fluid dynamics (CFD) flow solvers and has an empirical model for the supercooled large droplet (SLD) regime. An extensive comparison of the results in a quantifiable manner against the database of ice shapes and collection efficiency that have been generated in the NASA Glenn Icing Research Tunnel (IRT) has also been performed. The complete set of data used for this comparison will eventually be available in a contractor report. This paper will show the differences in collection efficiency between LEWICE 3.0 and experimental data. Due to the large amount of validation data available, a separate report is planned for ice shape comparison. This report will first describe the LEWICE 3.0 model for water collection. A semi-empirical approach was used to incorporate first order physical effects of large droplet phenomena into icing software. Comparisons are then made to every single element two-dimensional case in the water collection database. Each condition was run using the following five assumptions: 1) potential flow, no splashing; 2) potential flow, no splashing with 21 bin drop size distributions and a lift correction (angle of attack adjustment); 3) potential flow, with splashing; 4) Navier-Stokes, no splashing; and 5) Navier-Stokes, with splashing. Quantitative comparisons are shown for impingement limit, maximum water catch, and total collection efficiency. The results show that the predicted results are within the accuracy limits of the experimental data for the majority of cases.

Reproducibility and validity of a semi-quantitative FFQ for trace elements.

PubMed

Lee, Yujin; Park, Kyong

2016-09-01

The aim of this study was to test the reproducibility and validity of a self-administered FFQ for the Trace Element Study of Korean Adults in the Yeungnam area (SELEN). Study subjects were recruited from the SELEN cohort selected from rural and urban areas in Yeungnam, Korea. A semi-quantitative FFQ with 146 items was developed considering the dietary characteristics of cohorts in the study area. In a validation study, seventeen men and forty-eight women aged 38-62 years completed 3-d dietary records (DR) and two FFQ over a 3-month period. The validity was examined with the FFQ and DR, and the reproducibility was estimated using partial correlation coefficients, the Bland-Altman method and cross-classification. There were no significant differences between the mean intakes of selected nutrients as estimated from FFQ1, FFQ2 and DR. The median correlation coefficients for all nutrients were 0·47 and 0·56 in the reproducibility and validity tests, respectively. Bland-Altman's index and cross-classification showed acceptable agreement between FFQ1 and FFQ2 and between FFQ2 and DR. Ultimately, 78 % of the subjects were classified into the same and adjacent quartiles for most nutrients. In addition, the weighted κ value indicated that the two methods agreed fairly. In conclusion, this newly developed FFQ was a suitable dietary assessment method for the SELEN cohort study.

External validation of a risk assessment model for venous thromboembolism in the hospitalised acutely-ill medical patient (VTE-VALOURR).

PubMed

Mahan, Charles E; Liu, Yang; Turpie, A Graham; Vu, Jennifer T; Heddle, Nancy; Cook, Richard J; Dairkee, Undaleeb; Spyropoulos, Alex C

2014-10-01

Venous thromboembolic (VTE) risk assessment remains an important issue in hospitalised, acutely-ill medical patients, and several VTE risk assessment models (RAM) have been proposed. The purpose of this large retrospective cohort study was to externally validate the IMPROVE RAM using a large database of three acute care hospitals. We studied 41,486 hospitalisations (28,744 unique patients) with 1,240 VTE hospitalisations (1,135 unique patients) in the VTE cohort and 40,246 VTE-free hospitalisations (27,609 unique patients) in the control cohort. After chart review, 139 unique VTE patients were identified and 278 randomly-selected matched patients in the control cohort. Seven independent VTE risk factors as part of the RAM in the derivation cohort were identified. In the validation cohort, the incidence of VTE was 0.20%; 95% confidence interval (CI) 0.18-0.22, 1.04%; 95%CI 0.88-1.25, and 4.15%; 95%CI 2.79-8.12 in the low, moderate, and high VTE risk groups, respectively, which compared to rates of 0.45%, 1.3%, and 4.74% in the three risk categories of the derivation cohort. For the derivation and validation cohorts, the total percentage of patients in low, moderate and high VTE risk occurred in 68.6% vs 63.3%, 24.8% vs 31.1%, and 6.5% vs 5.5%, respectively. Overall, the area under the receiver-operator characteristics curve for the validation cohort was 0.7731. In conclusion, the IMPROVE RAM can accurately identify medical patients at low, moderate, and high VTE risk. This will tailor future thromboprophylactic strategies in this population as well as identify particularly high VTE risk patients in whom multimodal or more intensive prophylaxis may be beneficial.

Validity of the Framingham point scores in the elderly: results from the Rotterdam study.

PubMed

Koller, Michael T; Steyerberg, Ewout W; Wolbers, Marcel; Stijnen, Theo; Bucher, Heiner C; Hunink, M G Myriam; Witteman, Jacqueline C M

2007-07-01

The National Cholesterol Education Program recommends assessing 10-year risk of coronary heart disease (CHD) in individuals free of established CHD with the Framingham Point Scores (FPS). Individuals with a risk >20% are classified as high risk and are candidates for preventive intervention. We aimed to validate the FPS in a European population of elderly subjects. Subjects free of established CHD at baseline were selected from the Rotterdam study, a population-based cohort of subjects 55 years or older in The Netherlands. We studied calibration, discrimination (c-index), and the accuracy of high-risk classifications. Events consisted of fatal CHD and nonfatal myocardial infarction. Among 6795 subjects, 463 died because of CHD and 336 had nonfatal myocardial infarction. Predicted 10-year risk of CHD was on average well calibrated for women (9.9% observed vs 10.1% predicted) but showed substantial overestimation in men (14.3% observed vs 19.8% predicted), particularly with increasing age. This resulted in substantial number of false-positive classifications (specificity 70%) in men. In women, discrimination of the FPS was better than that in men (c-index 0.73 vs 0.63, respectively). However, because of the low baseline risk of CHD and limited discriminatory power, only 33% of all CHD events occurred in women classified as high risk. The FPS need recalibration for elderly men with better incorporation of the effect of age. In elderly women, FPS perform reasonably well. However, maintaining the rational of the high-risk threshold requires better performing models for a population with low incidence of CHD.

Validating a Measure of Patient Self-efficacy in Disease Self-management Using a Population-based IBD Cohort: The IBD Self-efficacy Scale.

PubMed

Graff, Lesley A; Sexton, Kathryn A; Walker, John R; Clara, Ian; Targownik, Laura E; Bernstein, Charles N

2016-09-01

Self-efficacy describes a person's confidence in their ability to manage demands, and is predictive of health outcomes in chronic disease such as hospitalization and health status. However, meaningful measurement must be domain (e.g., disease) specific. This study aims to provide validation of the Inflammatory Bowel Disease Self-Efficacy scale (IBD-SE), using a population-based IBD sample. Manitoba IBD Cohort Study participants completed a survey and clinical interview at a mean of 12 years postdiagnosis (n = 121 Crohn's disease; n = 108 ulcerative colitis), which included validated measures of psychological functioning, disability, disease-specific quality of life, perceived health, and current and recent disease activity, in addition to the IBD-SE. The IBD-SE had high internal consistency (Cronbach's α = 0.97), and a 4-factor structure was confirmed. Construct validity was demonstrated as follows: the IBD-SE was strongly correlated with mastery (r = 0.53), highly correlated in the expected directions with measures of psychological well-being (r = 0.70), stress (r = -0.78), distress (r = -0.71), disability (r = -0.48), disease-specific quality of life (r = 0.68), and overall perceived health (r = 0.52) (all P < 0.001). Those with currently inactive disease had higher self-efficacy than the active disease group (Crohn's disease: mean = 232 versus 195, P < 0.001; ulcerative colitis: mean = 233 versus 202, P < 0.01), with similar findings for recent symptomatic disease activity. The IBD-SE is a reliable, valid, and sensitive measure as demonstrated in this population-based sample, supporting its utility in IBD. Because self-efficacy is a modifiable psychological characteristic that can contribute to positive health outcomes, the IBD-SE may prove to be a valuable instrument for research and in targeted intervention with IBD patients.

Measuring IBS patient reported outcomes with an abdominal pain numeric rating scale: results from the proof cohort

PubMed Central

SPIEGEL, B.; BOLUS, R.; HARRIS, L. A.; LUCAK, S.; NALIBOFF, B.; ESRAILIAN, E.; CHEY, W. D.; LEMBO, A.; KARSAN, H.; TILLISCH, K.; TALLEY, J.; MAYER, E.; CHANG, L.

2009-01-01

Background Controversy exists about how to effectively measure patient reported outcomes in IBS clinical trials. Pain numeric rating scales (NRS) are widely used in the non-IBS pain literature. The FDA has proposed using the NRS in IBS. Aim To test the psychometrics of an abdominal pain NRS in IBS. Methods We analyzed data from a longitudinal cohort of Rome III IBS subjects. At entry, subjects completed a 10-point NRS, bowel symptoms, IBS severity measurements (IBSSS, FBDSI), health related quality of life indices (IBS-QOL, EQ5D), and the worker productivity activity index (WPAI). We repeated assessments at 3 months along with a response scale to calculate the minimal clinically important difference (MCID). Results There were 277 subjects (82% women; age=42±15) at baseline and 90 at 3 months. The NRS correlated cross-sectionally with IBSSS (r=0.60; p<0.0011), FBDSI (r=0.49; p<0.0001), IBS-QOL (r=0.43; p<0.0001), EQ5D (r=0.48; p<0.0001), presenteeism (r=0.39; p<0.0001), absenteeism (r=0.17; p=0.04), and distension (r=0.46; p<0.0001), but not stool frequency or form. The MCID was 2.2 points, correlating with a 29.5% reduction over time. Conclusions An abdominal pain NRS exhibits excellent validity and can be readily interpreted with an MCID in patients with IBS. These data support the use of the NRS in IBS clinical trials. PMID:19751360

Thromboembolism in inflammatory bowel disease: results from a prospective, population-based European inception cohort.

PubMed

Isene, Rune; Bernklev, Tomm; Høie, Ole; Langholz, Ebbe; Tsianos, Epameonondas; Stockbrügger, Reinhold; Odes, Selwyn; Småstuen, Milada; Moum, Bjørn

2014-07-01

Patients with inflammatory bowel disease (IBD) have proven an increased risk of venous thromboembolism (VTE), particularly when hospitalized. The estimate of the true risk varies considerably between studies, primarily due to differences in methodology. We set out to determine the incidence of VTE in a population-based European inception cohort. IBD patients were incepted into a cohort that was prospectively followed from the early 1990s to the early 2000s. A total of 1145 patients were followed for a total of 10,634 patient-years (p.y.). A total of 19 thromboembolic events were identified - 13 deep vein thrombosis and 6 with pulmonary embolism. The incidence rate of VTE was 1.8 per 1000 p.y. The risk of VTE was elevated in this IBD cohort but lower than previously reported. The highest risk was seen in hospitalized patients, but corticosteroids-requiring disease in outpatients also conferred some risk.

Validity of preeclampsia registration in the Medical Birth Registry of Norway for women participating in the Norwegian Mother and Child Cohort Study, 1999-2010

PubMed Central

Harmon, Quaker E.; Skard, Linn Beate; Simonsen, Ingeborg; Austvoll, Elise; Alsaker, Elin Hilde Roti; Starling, Anne; Trogstad, Lill; Magnus, Per; Engel, Stephanie

2014-01-01

Background The Norwegian Mother and Child Cohort study (MoBa), a prospective population-based pregnancy cohort, is a valuable database for studying causes of preeclampsia. Preeclampsia data in MoBa comes from the Medical Birth Registry of Norway (MBRN), thus, we wanted to study the validity of MBRN preeclampsia registration for MoBa women. Methods We selected all MoBa pregnancies with preeclampsia registered in the MBRN (n=4081) and a random control group (n=2000) without preeclampsia registrations. After excluding two delivery units not participating in MoBa and one no longer operating, units were asked to provide copies of antenatal charts with blood pressure and urinary measurements from all antenatal visits during pregnancy, and hospital discharge codes from the delivery stay. We received data for 5340 pregnancies delivered 1999-2010 (87% of all eligible). We calculated positive predictive value (PPV), sensitivity and specificity of MBRN registration, using hypertension and proteinuria on the antenatal charts and/or hospital discharge codes indicating preeclampsia as gold standard. Results Overall PPV was 83.9% (95% confidence interval 82.7, 85.1), and was higher when women were primiparous, or delivered preterm or low birth weight infants. Severe preeclampsia in the MBRN was found to be a true severe preeclampsia in 70% of cases. Extrapolating to the total MoBa population, the estimated sensitivity was low: 43.0% (38.7, 48.2), while specificity was high: 99.2% (99.2, 99.3). False negative cases seemed to have mild forms of preeclampsia. Conclusions PPV and specificity of preeclampsia registration in the MBRN during 1999-2010 was satisfactory, while sensitivity was low. PMID:25040774

The Bronchiectasis Severity Index. An International Derivation and Validation Study

PubMed Central

Goeminne, Pieter; Aliberti, Stefano; McDonnell, Melissa J.; Lonni, Sara; Davidson, John; Poppelwell, Lucy; Salih, Waleed; Pesci, Alberto; Dupont, Lieven J.; Fardon, Thomas C.; De Soyza, Anthony; Hill, Adam T.

2014-01-01

Rationale: There are no risk stratification tools for morbidity and mortality in bronchiectasis. Identifying patients at risk of exacerbations, hospital admissions, and mortality is vital for future research. Objectives: This study describes the derivation and validation of the Bronchiectasis Severity Index (BSI). Methods: Derivation of the BSI used data from a prospective cohort study (Edinburgh, UK, 2008–2012) enrolling 608 patients. Cox proportional hazard regression was used to identify independent predictors of mortality and hospitalization over 4-year follow-up. The score was validated in independent cohorts from Dundee, UK (n = 218); Leuven, Belgium (n = 253); Monza, Italy (n = 105); and Newcastle, UK (n = 126). Measurements and Main Results: Independent predictors of future hospitalization were prior hospital admissions, Medical Research Council dyspnea score greater than or equal to 4, FEV1 < 30% predicted, Pseudomonas aeruginosa colonization, colonization with other pathogenic organisms, and three or more lobes involved on high-resolution computed tomography. Independent predictors of mortality were older age, low FEV1, lower body mass index, prior hospitalization, and three or more exacerbations in the year before the study. The derived BSI predicted mortality and hospitalization: area under the receiver operator characteristic curve (AUC) 0.80 (95% confidence interval, 0.74–0.86) for mortality and AUC 0.88 (95% confidence interval, 0.84–0.91) for hospitalization, respectively. There was a clear difference in exacerbation frequency and quality of life using the St. George’s Respiratory Questionnaire between patients classified as low, intermediate, and high risk by the score (P < 0.0001 for all comparisons). In the validation cohorts, the AUC for mortality ranged from 0.81 to 0.84 and for hospitalization from 0.80 to 0.88. Conclusions: The BSI is a useful clinical predictive tool that identifies patients at risk of future mortality

Development and validation of a novel predictive scoring model for microvascular invasion in patients with hepatocellular carcinoma.

PubMed

Zhao, Hui; Hua, Ye; Dai, Tu; He, Jian; Tang, Min; Fu, Xu; Mao, Liang; Jin, Huihan; Qiu, Yudong

2017-03-01

Microvascular invasion (MVI) in patients with hepatocellular carcinoma (HCC) cannot be accurately predicted preoperatively. This study aimed to establish a predictive scoring model of MVI in solitary HCC patients without macroscopic vascular invasion. A total of 309 consecutive HCC patients who underwent curative hepatectomy were divided into the derivation (n=206) and validation cohort (n=103). A predictive scoring model of MVI was established according to the valuable predictors in the derivation cohort based on multivariate logistic regression analysis. The performance of the predictive model was evaluated in the derivation and validation cohorts. Preoperative imaging features on CECT, such as intratumoral arteries, non-nodular type of HCC and absence of radiological tumor capsule were independent predictors for MVI. The predictive scoring model was established according to the β coefficients of the 3 predictors. Area under receiver operating characteristic (AUROC) of the predictive scoring model was 0.872 (95% CI, 0.817-0.928) and 0.856 (95% CI, 0.771-0.940) in the derivation and validation cohorts. The positive and negative predictive values were 76.5% and 88.0% in the derivation cohort and 74.4% and 88.3% in the validation cohort. The performance of the model was similar between the patients with tumor size ≤5cm and >5cm in AUROC (P=0.910). The predictive scoring model based on intratumoral arteries, non-nodular type of HCC, and absence of the radiological tumor capsule on preoperative CECT is of great value in the prediction of MVI regardless of tumor size. Copyright © 2017 Elsevier B.V. All rights reserved.

Utilisation and Safety of Deferasirox: Results from an Observational Cohort Study in England.

PubMed

Osborne, Vicki; Davies, Miranda; Layton, Deborah; Shakir, Saad A W

2018-03-01

Deferasirox (EXJADE ® , Novartis, UK) is an oral iron-chelating agent primarily used to reduce chronic iron overload in patients receiving blood transfusions for various chronic anaemias and some non-transfusion dependant anaemias. The aim of this study was to examine the utilisation and safety of deferasirox used in general practice in England. A single exposure observational cohort study design was used. Patients were identified from dispensed prescriptions for deferasirox between September 2006 and September 2014. Outcome data were collected via postal questionnaires sent to prescribers ≥ 6 months after first dispensed prescription for an individual patient. Summary descriptive statistics were calculated. The evaluable cohort consisted of 122 patients, of which 41.8% were aged 2-17 years. Frequent reasons for prescribing were sickle cell anaemia (27/103 where specified, 26.2%) and beta thalassaemia (26, 25.2%). The majority of patients (43/51, 84.3%) were prescribed the licensed doses of 10 or 20 mg/kg/day at start. Prior measurements of serum creatinine were only reported for a small proportion this study (18/122, 14.8%). In total, 91 incident events were reported, including two of raised serum creatinine. These results show that deferasirox is largely being prescribed for its licensed indications in general practice in England and events reported were consistent with the known safety profile.

Relative validity of a semi-quantitative, web-based FFQ used in the 'Snart Forældre' cohort - a Danish study of diet and fertility.

PubMed

Knudsen, Vibeke K; Hatch, Elizabeth E; Cueto, Heidi; Tucker, Katherine L; Wise, Lauren; Christensen, Tue; Mikkelsen, Ellen M

2016-04-01

To assess the relative validity of a semi-quantitative, web-based FFQ completed by female pregnancy planners in the Danish 'Snart Forældre' study. We validated a web-based FFQ based on the FFQ used in the Danish National Birth Cohort against a 4 d food diary (FD) and assessed the relative validity of intakes of foods and nutrients. We compared means and medians of intakes, and calculated Pearson correlation coefficients and de-attenuated coefficients to assess agreement between the two methods. We also calculated the proportion correctly classified based on the same or adjacent quintile of intake and the proportion of grossly misclassified (extreme quintiles). Participants (n 128) in the 'Snart Forældre' study who had completed the web-based FFQ were invited to participate in the validation study. Participants in the 'Snart Forældre' study, in total ninety-seven women aged 20-42 years. Reported intakes of dairy products, vegetables and potatoes were higher in the FFQ compared with the FD, whereas reported intakes of fruit, meat, sugar and beverages were lower in the FFQ than in the FD. Overall the de-attenuated correlation coefficients were acceptable, ranging from 0·33 for energy to 0·93 for vitamin D. The majority of the women were classified in the same or adjacent quintile and few women were misclassified (extreme quintiles). The web-based FFQ performs well for ranking women of reproductive age according to high or low intake of foods and nutrients and, thus, provides a solid basis for investigating associations between diet and fertility.

Validation of the DECAF score to predict hospital mortality in acute exacerbations of COPD

PubMed Central

Echevarria, C; Steer, J; Heslop-Marshall, K; Stenton, SC; Hickey, PM; Hughes, R; Wijesinghe, M; Harrison, RN; Steen, N; Simpson, AJ; Gibson, GJ; Bourke, SC

2016-01-01

Background Hospitalisation due to acute exacerbations of COPD (AECOPD) is common, and subsequent mortality high. The DECAF score was derived for accurate prediction of mortality and risk stratification to inform patient care. We aimed to validate the DECAF score, internally and externally, and to compare its performance to other predictive tools. Methods The study took place in the two hospitals within the derivation study (internal validation) and in four additional hospitals (external validation) between January 2012 and May 2014. Consecutive admissions were identified by screening admissions and searching coding records. Admission clinical data, including DECAF indices, and mortality were recorded. The prognostic value of DECAF and other scores were assessed by the area under the receiver operator characteristic (AUROC) curve. Results In the internal and external validation cohorts, 880 and 845 patients were recruited. Mean age was 73.1 (SD 10.3) years, 54.3% were female, and mean (SD) FEV1 45.5 (18.3) per cent predicted. Overall mortality was 7.7%. The DECAF AUROC curve for inhospital mortality was 0.83 (95% CI 0.78 to 0.87) in the internal cohort and 0.82 (95% CI 0.77 to 0.87) in the external cohort, and was superior to other prognostic scores for inhospital or 30-day mortality. Conclusions DECAF is a robust predictor of mortality, using indices routinely available on admission. Its generalisability is supported by consistent strong performance; it can identify low-risk patients (DECAF 0–1) potentially suitable for Hospital at Home or early supported discharge services, and high-risk patients (DECAF 3–6) for escalation planning or appropriate early palliation. Trial registration number UKCRN ID 14214. PMID:26769015

Derivation and validation of a two-biomarker panel for diagnosis of ARDS in patients with severe traumatic injuries

PubMed Central

Ware, Lorraine B; Zhao, Zhiguo; Koyama, Tatsuki; Brown, Ryan M; Semler, Matthew W; Janz, David R; May, Addison K; Fremont, Richard D; Matthay, Michael A; Cohen, Mitchell J; Calfee, Carolyn S

2017-01-01

Background Acute respiratory distress syndrome (ARDS) is common after severe traumatic injuries but is underdiagnosed and undertreated. We hypothesized that a panel of plasma biomarkers could be used to diagnose ARDS in severe trauma. To test this hypothesis, we derived and validated a biomarker panel in three independent cohorts and compared the diagnostic performance to clinician recognition of ARDS. Methods Eleven plasma biomarkers of inflammation, lung epithelial and endothelial injury were measured in a derivation cohort of 439 severe trauma patients. ARDS status was analyzed by two-investigator consensus, and cases were required to meet Berlin criteria on intensive care unit (ICU) day 1. Controls were subjects without ARDS during the first 4 days of study enrollment. A multivariable logistic regression model was used to generate probabilities for ARDS. A reduced model with the top two performing markers was then tested in two independent validation cohorts. To assess clinical diagnosis of ARDS, medical records in the derivation cohort were systematically searched for documentation of ARDS diagnosis made by a clinical provider. Results Among 11 biomarkers, the combination of the endothelial injury marker angiopoietin-2 (Ang-2) and the lung epithelial injury marker receptor for advanced glycation endproducts (RAGE) provided good discrimination for ARDS in the derivation cohort (area under the curve (AUC)=0.74 (95% CI 0.67 to 0.80). In the validation cohorts, the AUCs for this model were 0.70 (0.61 to 0.77) and 0.78 (0.71 to 0.84). In contrast, provider assessment demonstrated poor diagnostic accuracy for ARDS, with AUC of 0.55 (0.51 to 0.60). Discussion A two-biomarker panel consisting of Ang-2 and RAGE performed well across multiple patient cohorts and outperformed clinical providers for diagnosing ARDS in severe trauma. Clinical application of this model could improve both diagnosis and treatment of ARDS in patients with severe trauma. Level of evidence

Screening for postdeployment conditions: development and cross-validation of an embedded validity scale in the neurobehavioral symptom inventory.

PubMed

Vanderploeg, Rodney D; Cooper, Douglas B; Belanger, Heather G; Donnell, Alison J; Kennedy, Jan E; Hopewell, Clifford A; Scott, Steven G

2014-01-01

To develop and cross-validate internal validity scales for the Neurobehavioral Symptom Inventory (NSI). Four existing data sets were used: (1) outpatient clinical traumatic brain injury (TBI)/neurorehabilitation database from a military site (n = 403), (2) National Department of Veterans Affairs TBI evaluation database (n = 48 175), (3) Florida National Guard nonclinical TBI survey database (n = 3098), and (4) a cross-validation outpatient clinical TBI/neurorehabilitation database combined across 2 military medical centers (n = 206). Secondary analysis of existing cohort data to develop (study 1) and cross-validate (study 2) internal validity scales for the NSI. The NSI, Mild Brain Injury Atypical Symptoms, and Personality Assessment Inventory scores. Study 1: Three NSI validity scales were developed, composed of 5 unusual items (Negative Impression Management [NIM5]), 6 low-frequency items (LOW6), and the combination of 10 nonoverlapping items (Validity-10). Cut scores maximizing sensitivity and specificity on these measures were determined, using a Mild Brain Injury Atypical Symptoms score of 8 or more as the criterion for invalidity. Study 2: The same validity scale cut scores again resulted in the highest classification accuracy and optimal balance between sensitivity and specificity in the cross-validation sample, using a Personality Assessment Inventory Negative Impression Management scale with a T score of 75 or higher as the criterion for invalidity. The NSI is widely used in the Department of Defense and Veterans Affairs as a symptom-severity assessment following TBI, but is subject to symptom overreporting or exaggeration. This study developed embedded NSI validity scales to facilitate the detection of invalid response styles. The NSI Validity-10 scale appears to hold considerable promise for validity assessment when the NSI is used as a population-screening tool.

Validation of microRNA pathway polymorphisms in esophageal adenocarcinoma survival.

PubMed

Faluyi, Olusola O; Eng, Lawson; Qiu, Xin; Che, Jiahua; Zhang, Qihuang; Cheng, Dangxiao; Ying, Nanjiao; Tse, Alvina; Kuang, Qin; Dodbiba, Lorin; Renouf, Daniel J; Marsh, Sharon; Savas, Sevtap; Mackay, Helen J; Knox, Jennifer J; Darling, Gail E; Wong, Rebecca K S; Xu, Wei; Azad, Abul Kalam; Liu, Geoffrey

2017-02-01

Polymorphisms in miRNA and miRNA pathway genes have been previously associated with cancer risk and outcome, but have not been studied in esophageal adenocarcinoma outcomes. Here, we evaluate candidate miRNA pathway polymorphisms in esophageal adenocarcinoma prognosis and attempt to validate them in an independent cohort of esophageal adenocarcinoma patients. Among 231 esophageal adenocarcinoma patients of all stages/treatment plans, 38 candidate genetic polymorphisms (17 biogenesis, 9 miRNA targets, 5 pri-miRNA, 7 pre-miRNA) were genotyped and analyzed. Cox proportional hazard models adjusted for sociodemographic and clinicopathological covariates helped assess the association of genetic polymorphisms with overall survival (OS) and progression-free survival (PFS). Significantly associated polymorphisms were then evaluated in an independent cohort of 137 esophageal adenocarcinoma patients. Among the 231 discovery cohort patients, 86% were male, median diagnosis age was 64 years, 34% were metastatic at diagnosis, and median OS and PFS were 20 and 12 months, respectively. GEMIN3 rs197412 (aHR = 1.37, 95%CI: [1.04-1.80]; P = 0.02), hsa-mir-124-1 rs531564 (aHR = 0.60, 95% CI: [0.53-0.90]; P = 0.05), and KIAA0423 rs1053667 (aHR = 0.51, 95% CI: [0.28-0.96]; P = 0.04) were found associated with OS. Furthermore, GEMIN3 rs197412 (aHR = 1.33, 95% CI: [1.03-1.74]; P = 0.03) and KRT81 rs3660 (aHR = 1.29, 95% CI: [1.01-1.64]; P = 0.04) were found associated with PFS. Although none of these polymorphisms were significant in the second cohort, hsa-mir-124-1 rs531564 and KIAA0423 rs1053667 had trends in the same direction; when both cohorts were combined together, GEMIN3 rs197412, hsa-mir-124-1 rs531564, and KIAA0423 rs1053667 remained significantly associated with OS. We demonstrate the association of multiple miRNA pathway polymorphisms with esophageal adenocarcinoma prognosis in a discovery cohort of patients, which did not validate in a separate cohort

Temporal Trends of Suicide Mortality in Mainland China: Results from the Age-Period-Cohort Framework.

PubMed

Wang, Zhenkun; Wang, Jinyao; Bao, Junzhe; Gao, Xudong; Yu, Chuanhua; Xiang, Huiyun

2016-08-03

The aim of this study is to explore the long-term trends of suicide mortality in China. We implemented the age-period-cohort (APC) framework, using data from the Global Burden of Disease Study 2013. Our results showed that the net drift of suicide mortality was -4.727% (95% CI: -4.821% to -4.634%) per year for men and -6.633% (95% CI: -6.751% to -6.515%) per year for women, and the local drift values were below 0 in all age groups (p < 0.01 for all) for both sexes during the period of 1994-2013. Longitudinal age curves indicated that, in the same birth cohort, suicide death risk increased rapidly to peak at the life stage of 20-24 years old and 15-24 years old for men and women, respectively, and then showed a decelerated decline, followed by a rise thereafter after 54 years old for men and a slight one after 69 years old for women. The estimated period and cohort RRs were found to show similar monotonic downward patterns (significantly with p < 0.01 for all) for both sexes, with more quickly decreasing for women than for men during the whole period. The decreasing trend of suicide was likely to be related to the economic rapid growth, improvements in health care, enhancement on the level of education, and increasing awareness of suicide among the public in China. In addition, fast urbanization and the effective control of pesticides and rodenticides might be the special reasons behind these trends we observed in this study.

A Contemporary Prostate Biopsy Risk Calculator Based on Multiple Heterogeneous Cohorts.

PubMed

Ankerst, Donna P; Straubinger, Johanna; Selig, Katharina; Guerrios, Lourdes; De Hoedt, Amanda; Hernandez, Javier; Liss, Michael A; Leach, Robin J; Freedland, Stephen J; Kattan, Michael W; Nam, Robert; Haese, Alexander; Montorsi, Francesco; Boorjian, Stephen A; Cooperberg, Matthew R; Poyet, Cedric; Vertosick, Emily; Vickers, Andrew J

2018-05-16

Prostate cancer prediction tools provide quantitative guidance for doctor-patient decision-making regarding biopsy. The widely used online Prostate Cancer Prevention Trial Risk Calculator (PCPTRC) utilized data from the 1990s based on six-core biopsies and outdated grading systems. We prospectively gathered data from men undergoing prostate biopsy in multiple diverse North American and European institutions participating in the Prostate Biopsy Collaborative Group (PBCG) in order to build a state-of-the-art risk prediction tool. We obtained data from 15 611 men undergoing 16 369 prostate biopsies during 2006-2017 at eight North American institutions for model-building and three European institutions for validation. We used multinomial logistic regression to estimate the risks of high-grade prostate cancer (Gleason score ≥7) on biopsy based on clinical characteristics, including age, prostate-specific antigen, digital rectal exam, African ancestry, first-degree family history, and prior negative biopsy. We compared the PBCG model to the PCPTRC using internal cross-validation and external validation on the European cohorts. Cross-validation on the North American cohorts (5992 biopsies) yielded the PBCG model area under the receiver operating characteristic curve (AUC) as 75.5% (95% confidence interval: 74.2-76.8), a small improvement over the AUC of 72.3% (70.9-73.7) for the PCPTRC (p<0.0001). However, calibration and clinical net benefit were far superior for the PBCG model. Using a risk threshold of 10%, clinical use of the PBCG model would lead to the equivalent of 25 fewer biopsies per 1000 patients without missing any high-grade cancers. Results were similar on external validation on 10 377 European biopsies. The PBCG model should be used in place of the PCPTRC for prediction of prostate biopsy outcome. A contemporary risk tool for outcomes on prostate biopsy based on the routine clinical risk factors is now available for informed decision-making. Copyright �

External validation of anti-Müllerian hormone based prediction of live birth in assisted conception

PubMed Central

2013-01-01

Background Chronological age and oocyte yield are independent determinants of live birth in assisted conception. Anti-Müllerian hormone (AMH) is strongly associated with oocyte yield after controlled ovarian stimulation. We have previously assessed the ability of AMH and age to independently predict live birth in an Italian assisted conception cohort. Herein we report the external validation of the nomogram in 822 UK first in vitro fertilization (IVF) cycles. Methods Retrospective cohort consisting of 822 patients undergoing their first IVF treatment cycle at Glasgow Centre for Reproductive Medicine. Analyses were restricted to women aged between 25 and 42 years of age. All women had an AMH measured prior to commencing their first IVF cycle. The performance of the model was assessed; discrimination by the area under the receiver operator curve (ROCAUC) and model calibration by the predicted probability versus observed probability. Results Live births occurred in 29.4% of the cohort. The observed and predicted outcomes showed no evidence of miscalibration (p = 0.188). The ROCAUC was 0.64 (95% CI: 0.60, 0.68), suggesting moderate and similar discrimination to the original model. The ROCAUC for a continuous model of age and AMH was 0.65 (95% CI 0.61, 0.69), suggesting that the original categories of AMH were appropriate. Conclusions We confirm by external validation that AMH and age are independent predictors of live birth. Although the confidence intervals for each category are wide, our results support the assessment of AMH in larger cohorts with detailed baseline phenotyping for live birth prediction. PMID:23294733

Noninvasive assessment of mitral inertness: clinical results with numerical model validation

NASA Technical Reports Server (NTRS)

Firstenberg, M. S.; Greenberg, N. L.; Smedira, N. G.; McCarthy, P. M.; Garcia, M. J.; Thomas, J. D.

2001-01-01

Inertial forces (Mdv/dt) are a significant component of transmitral flow, but cannot be measured with Doppler echo. We validated a method of estimating Mdv/dt. Ten patients had a dual sensor transmitral (TM) catheter placed during cardiac surgery. Doppler and 2D echo was performed while acquiring LA and LV pressures. Mdv/dt was determined from the Bernoulli equation using Doppler velocities and TM gradients. Results were compared with numerical modeling. TM gradients (range: 1.04-14.24 mmHg) consisted of 74.0 +/- 11.0% inertial forcers (range: 0.6-12.9 mmHg). Multivariate analysis predicted Mdv/dt = -4.171(S/D (RATIO)) + 0.063(LAvolume-max) + 5. Using this equation, a strong relationship was obtained for the clinical dataset (y=0.98x - 0.045, r=0.90) and the results of numerical modeling (y=0.96x - 0.16, r=0.84). TM gradients are mainly inertial and, as validated by modeling, can be estimated with echocardiography.

Validity Assessment of Low-risk SCORE Function and SCORE Function Calibrated to the Spanish Population in the FRESCO Cohorts.

PubMed

Baena-Díez, José Miguel; Subirana, Isaac; Ramos, Rafael; Gómez de la Cámara, Agustín; Elosua, Roberto; Vila, Joan; Marín-Ibáñez, Alejandro; Guembe, María Jesús; Rigo, Fernando; Tormo-Díaz, María José; Moreno-Iribas, Conchi; Cabré, Joan Josep; Segura, Antonio; Lapetra, José; Quesada, Miquel; Medrano, María José; González-Diego, Paulino; Frontera, Guillem; Gavrila, Diana; Ardanaz, Eva; Basora, Josep; García, José María; García-Lareo, Manel; Gutiérrez-Fuentes, José Antonio; Mayoral, Eduardo; Sala, Joan; Dégano, Irene R; Francès, Albert; Castell, Conxa; Grau, María; Marrugat, Jaume

2018-04-01

To assess the validity of the original low-risk SCORE function without and with high-density lipoprotein cholesterol and SCORE calibrated to the Spanish population. Pooled analysis with individual data from 12 Spanish population-based cohort studies. We included 30 919 individuals aged 40 to 64 years with no history of cardiovascular disease at baseline, who were followed up for 10 years for the causes of death included in the SCORE project. The validity of the risk functions was analyzed with the area under the ROC curve (discrimination) and the Hosmer-Lemeshow test (calibration), respectively. Follow-up comprised 286 105 persons/y. Ten-year cardiovascular mortality was 0.6%. The ratio between estimated/observed cases ranged from 9.1, 6.5, and 9.1 in men and 3.3, 1.3, and 1.9 in women with original low-risk SCORE risk function without and with high-density lipoprotein cholesterol and calibrated SCORE, respectively; differences were statistically significant with the Hosmer-Lemeshow test between predicted and observed mortality with SCORE (P < .001 in both sexes and with all functions). The area under the ROC curve with the original SCORE was 0.68 in men and 0.69 in women. All versions of the SCORE functions available in Spain significantly overestimate the cardiovascular mortality observed in the Spanish population. Despite the acceptable discrimination capacity, prediction of the number of fatal cardiovascular events (calibration) was significantly inaccurate. Copyright © 2017 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Biochemical validation of food frequency questionnaire-estimated carotenoid, alpha-tocopherol, and folate intakes among African Americans and non-Hispanic Whites in the Southern Community Cohort Study.

PubMed

Signorello, Lisa B; Buchowski, Maciej S; Cai, Qiuyin; Munro, Heather M; Hargreaves, Margaret K; Blot, William J

2010-02-15

Few food frequency questionnaires (FFQs) have been developed specifically for use among African Americans, and reports of FFQ performance among African Americans or low-income groups assessed using biochemical indicators are scarce. The authors conducted a validation study within the Southern Community Cohort Study to evaluate FFQ-estimated intakes of alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin, lycopene, folate, and alpha-tocopherol in relation to blood levels of these nutrients. Included were 255 nonsmoking participants (125 African Americans, 130 non-Hispanic whites) who provided a blood sample at the time of study enrollment and FFQ administration in 2002-2004. Levels of biochemical indicators of each micronutrient (alpha-tocopherol among women only) significantly increased with increasing FFQ-estimated intake (adjusted correlation coefficients: alpha-carotene, 0.35; beta-carotene, 0.28; beta-cryptoxanthin, 0.35; lutein/zeaxanthin, 0.28; lycopene, 0.15; folate, 0.26; alpha-tocopherol, 0.26 among women; all P's < 0.05). Subjects in the top decile of FFQ intake had blood levels that were 27% (lycopene) to 178% (beta-cryptoxanthin) higher than those of subjects in the lowest decile. Satisfactory FFQ performance was noted even for participants with less than a high school education. Some variation was noted in the FFQ's ability to predict blood levels for subgroups defined by race, sex, and other characteristics, but overall the Southern Community Cohort Study FFQ appears to generate useful dietary exposure rankings in the cohort.

Derivation and Validation of a Renal Risk Score for People With Type 2 Diabetes

PubMed Central

Elley, C. Raina; Robinson, Tom; Moyes, Simon A.; Kenealy, Tim; Collins, John; Robinson, Elizabeth; Orr-Walker, Brandon; Drury, Paul L.

2013-01-01

OBJECTIVE Diabetes has become the leading cause of end-stage renal disease (ESRD). Renal risk stratification could assist in earlier identification and targeted prevention. This study aimed to derive risk models to predict ESRD events in type 2 diabetes in primary care. RESEARCH DESIGN AND METHODS The nationwide derivation cohort included adults with type 2 diabetes from the New Zealand Diabetes Cohort Study initially assessed during 2000–2006 and followed until December 2010, excluding those with pre-existing ESRD. The outcome was fatal or nonfatal ESRD event (peritoneal dialysis or hemodialysis for ESRD, renal transplantation, or death from ESRD). Risk models were developed using Cox proportional hazards models, and their performance was assessed in a separate validation cohort. RESULTS The derivation cohort included 25,736 individuals followed for up to 11 years (180,497 person-years; 86% followed for ≥5 years). At baseline, mean age was 62 years, median diabetes duration 5 years, and median HbA1c 7.2% (55 mmol/mol); 37% had albuminuria; and median estimated glomerular filtration rate (eGFR) was 77 mL/min/1.73 m2. There were 637 ESRD events (2.5%) during follow-up. Models that included sex, ethnicity, age, diabetes duration, albuminuria, serum creatinine, systolic blood pressure, HbA1c, smoking status, and previous cardiovascular disease status performed well with good discrimination and calibration in the derivation cohort and the validation cohort (n = 5,877) (C-statistics 0.89–0.92), improving predictive performance compared with previous models. CONCLUSIONS These 5-year renal risk models performed very well in two large primary care populations with type 2 diabetes. More accurate risk stratification could facilitate earlier intervention than using eGFR and/or albuminuria alone. PMID:23801726

PLCO Ovarian Phase III Validation Study — EDRN Public Portal

Cancer.gov

Our preliminary data indicate that the performance of CA 125 as a screening test for ovarian cancer can be improved upon by additional biomarkers. With completion of one additional validation step, we will be ready to test the performance of a consensus marker panel in a phase III validation study. Given the original aims of the PLCO trial, we believe that the PLCO represents an ideal longitudinal cohort offering specimens for phase III validation of ovarian cancer biomarkers.

Validation of the Spanish Version of the Eating Assessment Tool-10 (EAT-10spa) in Colombia. A Blinded Prospective Cohort Study.

PubMed

Giraldo-Cadavid, Luis Fernando; Gutiérrez-Achury, Alejandra María; Ruales-Suárez, Karem; Rengifo-Varona, Maria Leonor; Barros, Camilo; Posada, Andrés; Romero, Carlos; Galvis, Ana María

2016-06-01

Dysphagia might affect 12 % of the general population, and its complications include pneumonia, malnutrition, social isolation, and death. No validated Spanish symptom survey exists to quantify dysphagia symptoms among Latin Americans. Therefore, we performed a prospective cohort study in a tertiary care university hospital to validate the Spanish version of the 10-Item Eating-Assessment-Tool (EAT-10spa) for use in Colombia. After an interdisciplinary committee of five bilingual specialists evaluated the EAT-10spa (translated and validated in Spain) and deemed it appropriate for the Colombian culture, its feasibility, reliability, validity, sensitivity to change, and diagnostic capacity were evaluated. As a reference standard, we used the flexible endoscopic evaluation of swallowing with sensory testing and a standardized clinical evaluation. All assessments were blinded. In total, 133 subjects were included (52 % women, mean age 55 years) and completed the EAT-10spa (median completion time: 2 min [IQR 1-3 min]), 39 % of whom had an elementary-level education. Cronbach's α coefficient: 0.91; test-retest intra-class correlation coefficient: 0.94. The Spearman's correlation coefficient of the EAT-10spa with the 8-point penetration-aspiration scale was 0.54 (P < 0.001). The area under the receiver-operating-characteristic-curve (AUC-ROC) for dysphagia and aspiration were 0.79 (P < 0.001) and 0.81 (P < 0.001), respectively. The best cut-off points for dysphagia and aspiration were EAT-10spa ≥2 (sensitivity 93.6 %, specificity 36.4 %) and EAT-10spa ≥4 (sensitivity 94.3 %, specificity 49.5 %), respectively. A reduction in the EAT-10 ≥3 was the best cut-off point for a clinically significant improvement (AUC-ROC 0.83; P < 0.0001). The EAT-10spa showed excellent psychometric properties and discriminatory capacity for use in Colombia.

Retrospective Derivation and Validation of an Automated Electronic Search Algorithm to Identify Post Operative Cardiovascular and Thromboembolic Complications

PubMed Central

Tien, M.; Kashyap, R.; Wilson, G. A.; Hernandez-Torres, V.; Jacob, A. K.; Schroeder, D. R.

2015-01-01

Summary Background With increasing numbers of hospitals adopting electronic medical records, electronic search algorithms for identifying postoperative complications can be invaluable tools to expedite data abstraction and clinical research to improve patient outcomes. Objectives To derive and validate an electronic search algorithm to identify postoperative thromboembolic and cardiovascular complications such as deep venous thrombosis, pulmonary embolism, or myocardial infarction within 30 days of total hip or knee arthroplasty. Methods A total of 34 517 patients undergoing total hip or knee arthroplasty between January 1, 1996 and December 31, 2013 were identified. Using a derivation cohort of 418 patients, several iterations of a free-text electronic search were developed and refined for each complication. Subsequently, the automated search algorithm was validated on an independent cohort of 2 857 patients, and the sensitivity and specificities were compared to the results of manual chart review. Results In the final derivation subset, the automated search algorithm achieved a sensitivity of 91% and specificity of 85% for deep vein thrombosis, a sensitivity of 96% and specificity of 100% for pulmonary embolism, and a sensitivity of 100% and specificity of 95% for myocardial infarction. When applied to the validation cohort, the search algorithm achieved a sensitivity of 97% and specificity of 99% for deep vein thrombosis, a sensitivity of 97% and specificity of 100% for pulmonary embolism, and a sensitivity of 100% and specificity of 99% for myocardial infarction. Conclusions The derivation and validation of an electronic search strategy can accelerate the data abstraction process for research, quality improvement, and enhancement of patient care, while maintaining superb reliability compared to manual review. PMID:26448798

Development and validation of a risk score for chronic kidney disease in HIV infection using prospective cohort data from the D:A:D study.

PubMed

Mocroft, Amanda; Lundgren, Jens D; Ross, Michael; Law, Matthew; Reiss, Peter; Kirk, Ole; Smith, Colette; Wentworth, Deborah; Neuhaus, Jacqueline; Fux, Christoph A; Moranne, Olivier; Morlat, Phillipe; Johnson, Margaret A; Ryom, Lene

2015-03-01

Chronic kidney disease (CKD) is a major health issue for HIV-positive individuals, associated with increased morbidity and mortality. Development and implementation of a risk score model for CKD would allow comparison of the risks and benefits of adding potentially nephrotoxic antiretrovirals to a treatment regimen and would identify those at greatest risk of CKD. The aims of this study were to develop a simple, externally validated, and widely applicable long-term risk score model for CKD in HIV-positive individuals that can guide decision making in clinical practice. A total of 17,954 HIV-positive individuals from the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study with ≥3 estimated glomerular filtration rate (eGFR) values after 1 January 2004 were included. Baseline was defined as the first eGFR > 60 ml/min/1.73 m2 after 1 January 2004; individuals with exposure to tenofovir, atazanavir, atazanavir/ritonavir, lopinavir/ritonavir, other boosted protease inhibitors before baseline were excluded. CKD was defined as confirmed (>3 mo apart) eGFR ≤ 60 ml/min/1.73 m2. Poisson regression was used to develop a risk score, externally validated on two independent cohorts. In the D:A:D study, 641 individuals developed CKD during 103,185 person-years of follow-up (PYFU; incidence 6.2/1,000 PYFU, 95% CI 5.7-6.7; median follow-up 6.1 y, range 0.3-9.1 y). Older age, intravenous drug use, hepatitis C coinfection, lower baseline eGFR, female gender, lower CD4 count nadir, hypertension, diabetes, and cardiovascular disease (CVD) predicted CKD. The adjusted incidence rate ratios of these nine categorical variables were scaled and summed to create the risk score. The median risk score at baseline was -2 (interquartile range -4 to 2). There was a 1:393 chance of developing CKD in the next 5 y in the low risk group (risk score < 0, 33 events), rising to 1:47 and 1:6 in the medium (risk score 0-4, 103 events) and high risk groups (risk score ≥ 5, 505 events

Validation of serum amyloid α as an independent biomarker for progression-free and overall survival in metastatic renal cell cancer patients.

PubMed

Vermaat, Joost S; Gerritse, Frank L; van der Veldt, Astrid A; Roessingh, Wijnand M; Niers, Tatjana M; Oosting, Sjoukje F; Sleijfer, Stefan; Roodhart, Jeanine M; Beijnen, Jos H; Schellens, Jan H; Gietema, Jourik A; Boven, Epie; Richel, Dick J; Haanen, John B; Voest, Emile E

2012-10-01

We recently identified apolipoprotein A2 (ApoA2) and serum amyloid α (SAA) as independent prognosticators in metastatic renal cell carcinoma (mRCC) patients, thereby improving the accuracy of the Memorial-Sloan Kettering Cancer Center (MSKCC) model. Validate these results prospectively in a separate cohort of mRCC patients treated with tyrosine kinase inhibitors (TKIs). For training we used 114 interferon-treated mRCC patients (inclusion 2001-2006). For validation we studied 151 TKI-treated mRCC patients (inclusion 2003-2009). Using Cox proportional hazards regression analysis, SAA and ApoA2 were associated with progression-free survival (PFS) and overall survival (OS). In 72 TKI-treated patients, SAA levels were analyzed longitudinally as a potential early marker for treatment effect. Baseline ApoA2 and SAA levels significantly predicted PFS and OS in the training and validation cohorts. Multivariate analysis identified SAA in both separate patient sets as a robust and independent prognosticator for PFS and OS. In contrast to our previous findings, ApoA2 interacted with SAA in the validation cohort and did not contribute to a better predictive accuracy than SAA alone and was therefore excluded from further analysis. According to the tertiles of SAA levels, patients were categorized in three risk groups, demonstrating accurate risk prognostication. SAA as a single biomarker showed equal prognostic accuracy when compared with the multifactorial MSKCC risk mode. Using receiver operating characteristic analysis, SAA levels >71 ng/ml were designated as the optimal cut-off value in the training cohort, which was confirmed for its significant sensitivity and specificity in the validation cohort. Applying SAA >71 ng/ml as an additional risk factor significantly improved the predictive accuracy of the MSKCC model in both independent cohorts. Changes in SAA levels after 6-8 wk of TKI treatment had no value in predicting treatment outcome. SAA but not ApoA2 was shown to be

Validation of the absolute renal risk of dialysis/death in adults with IgA nephropathy secondary to Henoch-Schönlein purpura: a monocentric cohort study.

PubMed

Mohey, Hesham; Laurent, Blandine; Mariat, Christophe; Berthoux, Francois

2013-08-01

We established earlier the absolute renal risk (ARR) of dialysis/death (D/D) in primary IgA nephropathy (IgAN) which permitted accurate prospective prediction of final prognosis. This ARR was based on the potential presence at initial diagnosis of three major, independent, and equipotent risk factors such as hypertension, quantitative proteinuria≥1 g per day, and severe pathological lesions appreciated by our local classification scoring≥8 (range 0-20). We studied the validity of this ARR concept in secondary IgAN to predict future outcome and focused on Henoch-Schönlein purpura (HSP) nephritis. Our cohort of adults IgAN concerned 1064 patients with 101 secondary IgAN and was focused on 74 HSP (59 men) with a mean age of 38.6 at initial diagnosis and a mean follow-up of 11.8 years. Three major risk factors: hypertension, proteinuria≥1 g/d, and severe pathological lesions appreciated by our global optical score≥8 (GOS integrated all elementary histological lesions), were studied at biopsy-proven diagnosis and their presence defined the ARR scoring: 0 for none present, 3 for all present, 1 or 2 for the presence of any 1 or 2 risk factors. The primary end-point was composite with occurrence of dialysis or death before (D/D). We used classical statistics and both time-dependent Cox regression and Kaplan-Meier survival curve methods. The cumulative rate of D/D at 10 and 20 years post-onset was respectively 0 and 14% for ARR=0 (23 patients); 10 and 23% for ARR=1 (N=19); 27 and 33% for ARR=2 (N=24); and 81 and 100% (before 20 y) in the 8 patients with ARR=3 (P=0.0007). Prediction at time of diagnosis (time zero) of 10y cumulative rate of D/D event was 0% for ARR=0, 10% for ARR=1, 33% for ARR=2, and 100% by 8.5y for ARR=3 (P=0.0003) in this adequately treated cohort. This study clearly validates the Absolute Renal Risk of Dialysis/Death concept in a new cohort of HSP-IgAN with utility to individual management and in future clinical trials.

Independent validation of a new reirradiation risk score (RRRS) for glioma patients predicting post-recurrence survival: A multicenter DKTK/ROG analysis.

PubMed

Niyazi, Maximilian; Adeberg, Sebastian; Kaul, David; Boulesteix, Anne-Laure; Bougatf, Nina; Fleischmann, Daniel F; Grün, Arne; Krämer, Anna; Rödel, Claus; Eckert, Franziska; Paulsen, Frank; Kessel, Kerstin A; Combs, Stephanie E; Oehlke, Oliver; Grosu, Anca-Ligia; Seidlitz, Annekatrin; Lattermann, Annika; Krause, Mechthild; Baumann, Michael; Guberina, Maja; Stuschke, Martin; Budach, Volker; Belka, Claus; Debus, Jürgen

2018-04-01

Reirradiation (reRT) is a valid option with considerable efficacy in patients with recurrent high-grade glioma, but it is still not known which patients might be optimal candidates for a second course of irradiation. This study validated a newly developed prognostic score independently in an external patient cohort. The reRT risk score (RRRS) is based on a linear combination of initial histology, clinical performance status, and age derived from a multivariable model of 353 patients. This score can predict post-recurrence survival (PRS) after reRT. The validation dataset consisted of 212 patients. The RRRS differentiates three prognostic groups. Discrimination and calibration were maintained in the validation group. Median PRS times in the development cohort for the good/intermediate/poor risk categories were 14.2, 9.1, and 5.3 months, respectively. The respective groups within the validation cohort displayed median PRS times of 13.8, 8.8, and 3.8 months, respectively. Uno's C for development data was 0.64 (CI: 0.60-0.69) and for validation data 0.63 (CI: 0.58-0.68). The RRRS has been successfully validated in an independent patient cohort. This linear combination of three easily determined clinicopathological factors allows for a reliable classification of patients and may be used as stratification factor for future trials. Copyright © 2018 Elsevier B.V. All rights reserved.

Cross-cultural comparisons of the Mini-mental State Examination between Japanese and U.S. cohorts

PubMed Central

Meguro, Kenichi; Ishii, Hiroshi; Yamaguchi, Satoshi; Saxton, Judith A.; Ganguli, Mary

2009-01-01

Background The Mini-mental State Examination (MMSE) is widely used in Japan and the U.S.A. for cognitive screening in the clinical setting and in epidemiological studies. A previous Japanese community study reported distributions of the MMSE total score very similar to that of the U.S.A. Methods Data were obtained from the Monongahela Valley Independent Elder's Study (MoVIES), a representative sample of community-dwelling elderly people aged 65 and older living near Pittsburgh, U.S.A., and from the Tajiri Project, with similar aims in Tajiri, Japan. We examined item-by-item distributions of the MMSE between two cohorts, comparing (1) percentage of correct answers for each item within each cohort, and (2) relative difficulty of each item measured by Item Characteristic Curve analysis (ICC), which estimates log odds of obtaining a correct answer adjusted for the remaining MMSE items, demographic variables (age, gender, education) and interactions of demographic variables and cohort. Results Median MMSE scores were very similar between the two samples within the same education groups. However, the relative difficulty of each item differed substantially between the two cohorts. Specifically, recall and auditory comprehension were easier for the Tajiri group, but reading comprehension and sentence construction were easier for the MoVIES group. Conclusions Our results reaffirm the importance of validation and examination of thresholds in each cohort to be studied when a common instrument is used as a dementia screening tool or for defining cognitive impairment. PMID:18925977

Internal validation of the prognostic index for spine metastasis (PRISM) for stratifying survival in patients treated with spinal stereotactic radiosurgery.

PubMed

Jensen, Garrett; Tang, Chad; Hess, Kenneth R; Bishop, Andrew J; Pan, Hubert Y; Li, Jing; Yang, James N; Tannir, Nizar M; Amini, Behrang; Tatsui, Claudio; Rhines, Laurence; Brown, Paul D; Ghia, Amol J

2017-01-01

We sought to validate the Prognostic Index for Spinal Metastases (PRISM), a scoring system that stratifies patients into subgroups by overall survival.Methods and materials: The PRISM was previously created from multivariate Cox regression with patients enrolled in prospective single institution trials of stereotactic spine radiosurgery (SSRS) for spinal metastasis. We assess model calibration and discrimination within a validation cohort of patients treated off-trial with SSRS for metastatic disease at the same institution. The training and validation cohorts consisted of 205 and 249 patients respectively. Similar survival trends were shown in the 4 PRISM. Survival was significantly different between PRISM subgroups (P<0.0001). C-index for the validation cohort was 0.68 after stratification into subgroups. We internally validated the PRISM with patients treated off-protocol, demonstrating that it can distinguish subgroups by survival, which will be useful for individualizing treatment of spinal metastases and stratifying patients for clinical trials.

Development and Validation of a Novel Pediatric Appendicitis Risk Calculator (pARC).

PubMed

Kharbanda, Anupam B; Vazquez-Benitez, Gabriela; Ballard, Dustin W; Vinson, David R; Chettipally, Uli K; Kene, Mamata V; Dehmer, Steven P; Bachur, Richard G; Dayan, Peter S; Kuppermann, Nathan; O'Connor, Patrick J; Kharbanda, Elyse O

2018-04-01

We sought to develop and validate a clinical calculator that can be used to quantify risk for appendicitis on a continuous scale for patients with acute abdominal pain. The pediatric appendicitis risk calculator (pARC) was developed and validated through secondary analyses of 3 distinct cohorts. The derivation sample included visits to 9 pediatric emergency departments between March 2009 and April 2010. The validation sample included visits to a single pediatric emergency department from 2003 to 2004 and 2013 to 2015. Variables evaluated were as follows: age, sex, temperature, nausea and/or vomiting, pain duration, pain location, pain with walking, pain migration, guarding, white blood cell count, and absolute neutrophil count. We used stepwise regression to develop and select the best model. Test performance of the pARC was compared with the Pediatric Appendicitis Score (PAS). The derivation sample included 2423 children, 40% of whom had appendicitis. The validation sample included 1426 children, 35% of whom had appendicitis. The final pARC model included the following variables: sex, age, duration of pain, guarding, pain migration, maximal tenderness in the right-lower quadrant, and absolute neutrophil count. In the validation sample, the pARC exhibited near perfect calibration and a high degree of discrimination (area under the curve: 0.85; 95% confidence interval: 0.83 to 0.87) and outperformed the PAS (area under the curve: 0.77; 95% confidence interval: 0.75 to 0.80). By using the pARC, almost half of patients in the validation cohort could be accurately classified as at <15% risk or ≥85% risk for appendicitis, whereas only 23% would be identified as having a comparable PAS of <3 or >8. In our validation cohort of patients with acute abdominal pain, the pARC accurately quantified risk for appendicitis. Copyright © 2018 by the American Academy of Pediatrics.

Gender Differences of Children's Developmental Trajectory from 6 to 60 Months in the Taiwan Birth Cohort Pilot Study

ERIC Educational Resources Information Center

Lung, For-Wey; Chiang, Tung-Liang; Lin, Shio-Jean; Feng, Jui-Ying; Chen, Po-Fei; Shu, Bih-Ching

2011-01-01

The parental report instrument is the most efficient developmental detection method and has shown high validity with professional assessment instruments. The reliability and validity of the Taiwan Birth Cohort Study (TBCS) 6-, 18- and 36-month scales have already been established. In this study, the reliability and validity of the 60-month scale…

Monitoring sedation status over time in ICU patients: reliability and validity of the Richmond Agitation-Sedation Scale (RASS).

PubMed

Ely, E Wesley; Truman, Brenda; Shintani, Ayumi; Thomason, Jason W W; Wheeler, Arthur P; Gordon, Sharon; Francis, Joseph; Speroff, Theodore; Gautam, Shiva; Margolin, Richard; Sessler, Curtis N; Dittus, Robert S; Bernard, Gordon R

2003-06-11

Goal-directed delivery of sedative and analgesic medications is recommended as standard care in intensive care units (ICUs) because of the impact these medications have on ventilator weaning and ICU length of stay, but few of the available sedation scales have been appropriately tested for reliability and validity. To test the reliability and validity of the Richmond Agitation-Sedation Scale (RASS). Prospective cohort study. Adult medical and coronary ICUs of a university-based medical center. Thirty-eight medical ICU patients enrolled for reliability testing (46% receiving mechanical ventilation) from July 21, 1999, to September 7, 1999, and an independent cohort of 275 patients receiving mechanical ventilation were enrolled for validity testing from February 1, 2000, to May 3, 2001. Interrater reliability of the RASS, Glasgow Coma Scale (GCS), and Ramsay Scale (RS); validity of the RASS correlated with reference standard ratings, assessments of content of consciousness, GCS scores, doses of sedatives and analgesics, and bispectral electroencephalography. In 290-paired observations by nurses, results of both the RASS and RS demonstrated excellent interrater reliability (weighted kappa, 0.91 and 0.94, respectively), which were both superior to the GCS (weighted kappa, 0.64; P<.001 for both comparisons). Criterion validity was tested in 411-paired observations in the first 96 patients of the validation cohort, in whom the RASS showed significant differences between levels of consciousness (P<.001 for all) and correctly identified fluctuations within patients over time (P<.001). In addition, 5 methods were used to test the construct validity of the RASS, including correlation with an attention screening examination (r = 0.78, P<.001), GCS scores (r = 0.91, P<.001), quantity of different psychoactive medication dosages 8 hours prior to assessment (eg, lorazepam: r = - 0.31, P<.001), successful extubation (P =.07), and bispectral electroencephalography (r = 0.63, P

Vaccinations in early life are not associated with development of islet autoimmunity in type 1 diabetes high-risk children: Results from prospective cohort data.

PubMed

Beyerlein, Andreas; Strobl, Andreas N; Winkler, Christiane; Carpus, Michaela; Knopff, Annette; Donnachie, Ewan; Ankerst, Donna P; Ziegler, Anette-G

2017-03-27

Vaccinations in early childhood potentially stimulate the immune system and may thus be relevant for the pathogenesis of autoimmune diseases such as type 1 diabetes (T1D). We determined the association of vaccination burden with T1D-associated islet autoimmunity in children with high familial risk followed prospectively from birth. A total of 20,570 certified vaccination records from 1918 children were correlated with time to onset of T1D-associated islet autoimmunity using Cox regression, considering multiple time periods up until age two years and vaccination types, and adjusting for HLA genotype, sex, delivery mode, season of birth, preterm delivery and maternal T1D status. Additionally, prospective claims data of 295,420 subjects were used to validate associations for the tick-borne encephalitis (TBE) vaccination. Most vaccinations were not associated with a significantly increased hazard ratio (HR) for islet autoimmunity (e.g. HR [95% confidence interval]: 1.08 [0.96-1.21] per additional vaccination against measles, mumps and rubella at age 0-24months). TBE vaccinations within the first two years of life were nominally associated with a significantly increased autoimmunity risk (HR: 1.44 [1.06-1.96] per additional vaccination at age 0-24months), but this could not be confirmed with respect to outcome T1D in the validation cohort (HR: 1.02 [0.90-1.16]). We found no evidence that early vaccinations increase the risk of T1D-associated islet autoimmunity development. The potential association with early TBE vaccinations could not be confirmed in an independent cohort and appears to be a false positive finding. Copyright © 2017 Elsevier Ltd. All rights reserved.

Online Prediction of Health Care Utilization in the Next Six Months Based on Electronic Health Record Information: A Cohort and Validation Study.

PubMed

Hu, Zhongkai; Hao, Shiying; Jin, Bo; Shin, Andrew Young; Zhu, Chunqing; Huang, Min; Wang, Yue; Zheng, Le; Dai, Dorothy; Culver, Devore S; Alfreds, Shaun T; Rogow, Todd; Stearns, Frank; Sylvester, Karl G; Widen, Eric; Ling, Xuefeng

2015-09-22

The increasing rate of health care expenditures in the United States has placed a significant burden on the nation's economy. Predicting future health care utilization of patients can provide useful information to better understand and manage overall health care deliveries and clinical resource allocation. This study developed an electronic medical record (EMR)-based online risk model predictive of resource utilization for patients in Maine in the next 6 months across all payers, all diseases, and all demographic groups. In the HealthInfoNet, Maine's health information exchange (HIE), a retrospective cohort of 1,273,114 patients was constructed with the preceding 12-month EMR. Each patient's next 6-month (between January 1, 2013 and June 30, 2013) health care resource utilization was retrospectively scored ranging from 0 to 100 and a decision tree-based predictive model was developed. Our model was later integrated in the Maine HIE population exploration system to allow a prospective validation analysis of 1,358,153 patients by forecasting their next 6-month risk of resource utilization between July 1, 2013 and December 31, 2013. Prospectively predicted risks, on either an individual level or a population (per 1000 patients) level, were consistent with the next 6-month resource utilization distributions and the clinical patterns at the population level. Results demonstrated the strong correlation between its care resource utilization and our risk scores, supporting the effectiveness of our model. With the online population risk monitoring enterprise dashboards, the effectiveness of the predictive algorithm has been validated by clinicians and caregivers in the State of Maine. The model and associated online applications were designed for tracking the evolving nature of total population risk, in a longitudinal manner, for health care resource utilization. It will enable more effective care management strategies driving improved patient outcomes.

Validity of a family-centered approach for assessing infants' social-emotional wellbeing and their developmental context: a prospective cohort study.

PubMed

Hielkema, Margriet; De Winter, Andrea F; Reijneveld, Sijmen A

2017-06-15

Family-centered care seems promising in preventive pediatrics, but evidence is lacking as to whether this type of care is also valid as a means to identify risks to infants' social-emotional development. We aimed to examine the validity of such a family-centered approach. We conducted a prospective cohort study. During routine well-child visits (2-15 months), Preventive Child Healthcare (PCH) professionals used a family-centered approach, assessing domains as parents' competence, role of the partner, social support, barriers within the care-giving context, and child's wellbeing for 2976 children as protective, indistinct or a risk. If, based on the overall assessment (the families were labeled as "cases", N = 87), an intervention was considered necessary, parents filled in validated questionnaires covering the aforementioned domains. These questionnaires served as gold standards. For each case, two controls, matched by child-age and gender, also filled in questionnaires (N = 172). We compared PCH professionals' assessments with the parent-reported gold standards. Moreover, we evaluated which domain mostly contributed to the overall assessment. Spearman's rank correlation coefficients between PCH professionals' assessments and gold standards were overall reasonable (Spearman's rho 0.17-0.39) except for the domain barriers within the care-giving context. Scores on gold standards were significantly higher when PCH assessments were rated as "at risk" (overall and per domain).We found reasonable to excellent agreement regarding the absence of risk factors (negative agreement rate: 0.40-0.98), but lower agreement regarding the presence of risk factors (positive agreement rate: 0.00-0.67). An "at risk" assessment for the domain Barriers or life events within the care-giving context contributed most to being overall at risk, i.e. a case, odds ratio 100.1, 95%-confidence interval: 22.6 - infinity. Findings partially support the convergent validity of a family

Cohort profile: the Spanish WORKing life Social Security (WORKss) cohort study

PubMed Central

López Gómez, María Andrée; Durán, Xavier; Zaballa, Elena; Sanchez-Niubo, Albert; Delclos, George L; Benavides, Fernando G

2016-01-01

Purpose The global economy is changing the labour market and social protection systems in Europe. The effect of both changes on health needs to be monitored in view of an ageing population and the resulting increase in prevalence of chronic health conditions. The Spanish WORKing life Social Security (WORKss) cohort study provides unique longitudinal data to study the impact of labour trajectories and employment conditions on health, in terms of sickness absence, permanent disability and death. Participants The WORKss cohort originated from the Continuous Working Life Sample (CWLS) generated by the General Directorate for the Organization of the Social Security in Spain. The CWLS contains a 4% representative sample of all individuals in contact with the Social Security system. The WORKss cohort exclusively includes individuals with a labour trajectory from 1981 or later. In 2004, the cohort was initiated with 1 022 779 Social Security members: 840 770 (82.2%) contributors and 182 009 (17.8%) beneficiaries aged 16 and older. Findings to date The WORKss cohort includes demographic characteristics, chronological data about employment history, retirement, permanent disability and death. These data make possible the measurement of incidence of permanent disability, the number of potential years of working life lost, and the number of contracts and inactive periods with the Social Security system. The WORKss cohort was linked to temporary sickness absence registries to study medical diagnoses that lead to permanent disability and consequently to an earlier exit from the labour market in unhealthy conditions. Future plans Thanks to its administrative source, the WORKss cohort study will continue follow-up in the coming years, keeping the representativeness of the Spanish population affiliated to the Social Security system. The linkage between the WORKss cohort and temporary sickness absence registries is envisioned to continue. Future plans include the linkage of

Development and validation of a predictive risk model for all-cause mortality in type 2 diabetes.

PubMed

Robinson, Tom E; Elley, C Raina; Kenealy, Tim; Drury, Paul L

2015-06-01

Type 2 diabetes is common and is associated with an approximate 80% increase in the rate of mortality. Management decisions may be assisted by an estimate of the patient's absolute risk of adverse outcomes, including death. This study aimed to derive a predictive risk model for all-cause mortality in type 2 diabetes. We used primary care data from a large national multi-ethnic cohort of patients with type 2 diabetes in New Zealand and linked mortality records to develop a predictive risk model for 5-year risk of mortality. We then validated this model using information from a separate cohort of patients with type 2 diabetes. 26,864 people were included in the development cohort with a median follow up time of 9.1 years. We developed three models initially using demographic information and then progressively more clinical detail. The final model, which also included markers of renal disease, proved to give best prediction of all-cause mortality with a C-statistic of 0.80 in the development cohort and 0.79 in the validation cohort (7610 people) and was well calibrated. Ethnicity was a major factor with hazard ratios of 1.37 for indigenous Maori, 0.41 for East Asian and 0.55 for Indo Asian compared with European (P<0.001). We have developed a model using information usually available in primary care that provides good assessment of patient's risk of death. Results are similar to models previously published from smaller cohorts in other countries and apply to a wider range of patient ethnic groups. Copyright © 2015. Published by Elsevier Ireland Ltd.

Occupational exposures and sick leave during pregnancy: results from a Danish cohort study.

PubMed

Hansen, Mette Lausten; Thulstrup, Ane Marie; Juhl, Mette; Kristensen, Jette Kolding; Ramlau-Hansen, Cecilia Høst

2015-07-01

This study aimed to investigate associations between work postures, lifting at work, shift work, work hours, and job strain and the risk of sick leave during pregnancy from 10-29 completed pregnancy weeks in a large cohort of Danish pregnant women. Data from 51 874 pregnancies in the Danish National Birth Cohort collected between 1996-2002 were linked to the Danish Register for Evaluation of Marginalization. Exposure information was based on telephone interviews. Hazard ratios (HR) with 95% confidence intervals (95% CI) were calculated by Cox regression analysis, using time of first episode of sick leave as the primary outcome. We found statistically significant associations between all the predictors and risk of sick leave; for non-sitting work postures (HRrange 1.55-2.79), cumulative lifting HRtrend 1.29, 95% CI 1.26-1.31, shift work (HRevening 1.90, 95% CI 1.73-2.09, HRnight 1.52, 95% CI 1.15-2.01), monthly night shifts HRtrend 1.12, 95% CI 1.11-1.14, increasing weekly work hours HRtrend 0.93, 95% CI 0.91-0.95 and high job strain HR 1.52, 95% CI 1.42-1.63. Some exposures influenced HR in either a positive or negative time-dependent way. Our results support previous findings and suggest that initiatives to prevent sick leave during pregnancy could be based on work conditions. Preventive measures may have important implications for pregnant women and workplaces.

[Record linkage of a large clinical practice patient cohort with the Cancer Registry Schleswig-Holstein].

PubMed

Obi, N; Waldmann, A; Babaev, V; Katalinic, A

2011-07-01

A precondition for the evaluation of outcomes in cohort studies and screening programmes is the availability of follow-up data. In Germany, established cancer registries provide such data for incident primary cancer diseases and mortality. To utilise these cancer registry data a person's identifying code has to be correctly linked to study or programme records, a procedure which, up to date, has been only rarely used in Germany. Exemplarily, the feasibility and validity of record linkage of a cohort of 173 050 patients from the Quality-assured Mamma Diagnostic programme (QuaMaDi) to the cancer registry Schleswig-Holstein was assessed by the accuracy of the classified outcome. Name, date of birth and address of the QuaMaDi cohort members were coded in the confidential administration center of the registry. These codes were passed by the codes of 129 455 female cancer registry records. Datasets were synchronised for each match, so that QuaMaDi participants could be identified in the registry file. In a next step epidemiological registry records were linked to the QuaMaDi study records. The accuracy of classifying outcome was assessed by agreement measures, i. e., Cohen's kappa. In cases of disagreement, a questionnaire has been sent to QuaMaDi patients' gynaecologists to validate the final diagnosis. Synchronisation of both cohorts resulted in 18 689 one to one matches with any kind of malignant tumour, therein 8 449 breast cancers (ICD-10 C50, D05). Absolute agreement between files according to diagnosed or suspected breast cancer was 97.6% with a kappa value of 0.79. When suspicious BIRADS 4 cases from QuaMaDi were excluded, agreement and kappa rose to 99.5% and 0.948, respectively. After correction of the final diagnosis according to the physician's responses, agreement measures slightly improved in both groups of ascertained diagnosis including and excluding the suspected cases. Within QuaMaDi the diagnosed breast cancer cases were predominantly

Psychiatric disorders in women with fertility problems: results from a large Danish register-based cohort study.

PubMed

Baldur-Felskov, B; Kjaer, S K; Albieri, V; Steding-Jessen, M; Kjaer, T; Johansen, C; Dalton, S O; Jensen, A

2013-03-01

Do women who don't succeed in giving birth after an infertility evaluation have a higher risk of psychiatric disorders compared with women who do? The results indicated that being unsuccessful in giving birth after an infertility evaluation could be an important risk factor for psychiatric disorders. Several studies have investigated the association between fertility treatment and psychological distress, but the results from these studies show substantial variation and lack of homogeneity that may be due to methodological limitations. A retrospective cohort study was designed using data from a cohort of 98 320 Danish women evaluated for fertility problems during 1973-2008 and linked to several Danish population-based registries. All women were followed from the date of first infertility evaluation until date of hospitalization for the psychiatric disorder in question, date of emigration, date of death or 31 December 2008, whichever occurred first. Owing to the precise linkage between the infertility cohort and the Danish population-based registries, using the unique Danish personal identification number, virtually no women were lost to follow-up. Information on reproductive status for all women in the infertility cohort was obtained by linkage to the Danish Medical Birth Registry. A total of 53 547 (54.5%) women gave birth after the initial infertility evaluation, whereas 44 773 (45.5%) women did not gave birth after the evaluation. To determine psychiatric disorders diagnosed in the women after enrolment in the infertility cohort, the cohort was linked to the Danish Psychiatric Central Registry. A total of 4633 women were hospitalized for a psychiatric disorder. The Cox proportional hazard regression model was applied to estimate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for the association between parity status after the initial infertility evaluation and risk of hospitalization for various groups of psychiatric disorders, including

Measuring Outcomes for Dysphagia: Validity and Reliability of the European Portuguese Eating Assessment Tool (P-EAT-10).

PubMed

Nogueira, Dália Santos; Ferreira, Pedro Lopes; Reis, Elizabeth Azevedo; Lopes, Inês Sousa

2015-10-01

The purpose of this study was to evaluate the validity and the reliability of the European Portuguese version of the EAT-10 (P-EAT-10). This research was conducted in three phases: (i) cultural and linguistic adaptation; (ii) feasibility and reliability test; and (iii) validity tests. The final sample was formed by a cohort of 520 subjects. The P-EAT-10 index was compared for socio-demographic and clinic variables. It was also compared for both dysphagic and non-dysphagic groups as well as for the results of the 3Oz wst. Lastly, the P-EAT-10 scores were correlated with the EuroQol Group Portuguese EQ-5D index. The Cronbach's α obtained for the P-EAT-10 scale was 0.952 and it remained excellent even if any item was deleted. The item-total and the intraclass correlation coefficients were very good. The P-EAT-10 mean of the non-dysphagic cohort was 0.56 and that of the dysphagic cohort was 14.26, the mean comparison between the 3Oz wst groups and the P-EAT-10 scores were significant. A significant higher perception of QoL was also found among the non-dysphagic subjects. P-EAT-10 is a valid and reliable measure that may be used to document dysphagia which makes it useful both for screening in clinical practice and in research.

Validity of the SAT® for Predicting First-Year Grades: 2009 SAT Validity Sample. Statistical Report No. 2012-2

ERIC Educational Resources Information Center

Patterson, Brian F.; Mattern, Krista D.

2009-01-01

In an effort to continuously monitor the validity of the SAT for predicting first-year college grades, the College Board has continued its multi-year effort to recruit four-year colleges and universities (henceforth, "institutions") to provide data on the cohorts of first-time, first-year students entering in the fall semester beginning…

[Linkage of large secondary and registry data sources with data of cohort studies : usage of a dual potential].

PubMed

Jacobs, Svenja; Stallmann, Christoph; Pigeot, Iris

2015-08-01

Cohort studies provide the best evidence of all epidemiological observational studies for the identification of causal relationships between risk factors and diseases. However, this design may lead to drawbacks that may affect the validity and reliability of the results. This follows in particular from systematic errors, such as selection bias or recall bias. One possibility to avoid or counteract some of these drawbacks is to link primary data from cohort studies with secondary and register data. The linkage of these data may also be used for mutual validations. Data that were previously linked with primary data within the context of cohort studies in Germany were obtained from statutory health insurances and pensions as well as data from the Federal Employment Agency and cancer registries. All these data have two features in common: First, they all cover detailed information about a large population and over a long period of time. Second, all sources are in principle able to provide data on an individual level such that an individual data linkage, e.g. with primary data, is possible. However, use and linkage of each of these data sources are restricted by several limitations. These have to be accounted for as well as numerous legal restrictions that exist in Germany to especially prevent the misuse of social data.

Reliability and validity of a combat exposure index for Vietnam era veterans.

PubMed

Janes, G R; Goldberg, J; Eisen, S A; True, W R

1991-01-01

The reliability and validity of a self-report measure of combat exposure are examined in a cohort of male-male twin pairs who served in the military during the Vietnam era. Test-retest reliability for a five-level ordinal index of combat exposure is assessed by use of 192 duplicate sets of responses. The chance-corrected proportion in agreement (as measured by the kappa coefficient) is .84. As a measure of criterion-related validity, the combat index is correlated with the award of combat-related military medals ascertained from the military records. The probability of receiving a Purple Heart, Bronze Star, Commendation Medal and Combat Infantry Badge is associated strongly with the combat exposure index. These results show that this simple index is a reliable and valid measure of combat exposure.

Validation of the CORB75 (confusion, oxygen saturation, respiratory rate, blood pressure, and age ≥ 75 years) as a simpler pneumonia severity rule.

PubMed

Ochoa-Gondar, O; Vila-Corcoles, A; Rodriguez-Blanco, T; Hospital, I; Salsench, E; Ansa, X; Saun, N

2014-04-01

This study compares the ability of two simpler severity rules (classical CRB65 vs. proposed CORB75) in predicting short-term mortality in elderly patients with community-acquired pneumonia (CAP). A population-based study was undertaken involving 610 patients ≥ 65 years old with radiographically confirmed CAP diagnosed between 2008 and 2011 in Tarragona, Spain (350 cases in the derivation cohort, 260 cases in the validation cohort). Severity rules were calculated at the time of diagnosis, and 30-day mortality was considered as the dependent variable. The area under the receiver operating characteristic curves (AUC) was used to compare the discriminative power of the severity rules. Eighty deaths (46 in the derivation and 34 in the validation cohorts) were observed, which gives a mortality rate of 13.1 % (15.6 % for hospitalized and 3.3 % for outpatient cases). After multivariable analyses, besides CRB (confusion, respiration rate ≥ 30/min, systolic blood pressure <90 mmHg or diastolic ≤ 60 mmHg), peripheral oxygen saturation (≤ 90 %) and age ≥ 75 years appeared to be associated with increasing 30-day mortality in the derivation cohort. The model showed adequate calibration for the derivation and validation cohorts. A modified CORB75 scoring system (similar to the classical CRB65, but adding oxygen saturation and increasing the age to 75 years) was constructed. The AUC statistics for predicting mortality in the derivation and validation cohorts were 0.79 and 0.82, respectively. In the derivation cohort, a CORB75 score ≥ 2 showed 78.3 % sensitivity and 65.5 % specificity for mortality (in the validation cohort, these were 82.4 and 71.7 %, respectively). The proposed CORB75 scoring system has good discriminative power in predicting short-term mortality among elderly people with CAP, which supports its use for severity assessment of these patients in primary care.

[Assessing incident cardiovascular and metabolic diseases in epidemiological cohort studies in Germany].

PubMed

Herrmann, Wolfram J; Weikert, Cornelia; Bergmann, Manuela; Boeing, Heiner; Katzke, Verena A; Kaaks, Rudolf; Tiller, Daniel; Greiser, Karin Halina; Heier, Margit; Meisinger, Christa; Schmidt, Carsten Oliver; Neuhauser, Hannelore; Heidemann, Christin; Jünger, Claus; Wild, Philipp S; Schramm, Sara Helena; Jöckel, Karl-Heinz; Dörr, Marcus; Pischon, Tobias

2018-04-01

Cardiovascular and metabolic diseases are a major cause of mortality and loss of quality of life in Germany. Research into risk factors of these diseases requires large population-based cohort studies. Complete and accurate assessment of the incidence of cardiovascular and metabolic diseases is a key element for valid interpretation of the results from such studies. Our aim was to identify population-based cohort studies with incidence of cardiovascular and metabolic diseases in Germany and to summarize their methods for assessment and classification of disease endpoints, including myocardial infarction, type 2 diabetes, stroke, heart failure, and arterial hypertension. Within the framework of a workshop, representatives of the ascertained population-based cohort studies in Germany with incidence of cardiovascular or metabolic diseases were invited to present and to systematically provide information on their methods of endpoint identification. We identified eight studies from different regions in Germany with a total of 100,571 participants, aged 18-83 years at baseline. Self-reporting by study participants is the major source for further inquiries to assess disease endpoints in these studies. Most studies use additional data sources to verify the incidence of diseases, such as documents provided by the treating physician or hospital. Our results highlight the central role of self-reporting and the efforts associated with identification and verification of disease endpoints in cohort studies. They also provide a basis for future population-based studies that aim for standardized assessment of the incidence of cardiovascular and metabolic diseases.

Age, time period, and birth cohort differences in self-esteem: Reexamining a cohort-sequential longitudinal study.

PubMed

Twenge, Jean M; Carter, Nathan T; Campbell, W Keith

2017-05-01

Orth, Trzesniewski, and Robins (2010) concluded that the nationally representative Americans' Changing Lives (ACL) cohort-sequential study demonstrated moderate to large age differences in self-esteem, and no birth cohort (generational) differences in the age trajectory. In a reanalysis of these data using 2 different statistical techniques, we find significant increases in self-esteem that could be attributed to birth cohort or time period. First, hierarchical linear modeling analyses with birth cohort as a continuous variable (vs. the multiple group formulation used by Orth et al.) find that birth cohort has a measurable influence on self-esteem through its interaction with age. Participants born in later years (e.g., 1960) were higher in self-esteem and were more likely to increase in self-esteem as they aged than participants born in earlier years (e.g., 1920). However, the estimated age trajectory up to age 60 is similar in Orth et al.'s results and in the results from our analyses including cohort. Second, comparing ACL respondents of the same age in 1986 versus 2002 (a time-lag design) yields significant birth cohort differences in self-esteem, with 2002 participants of the same age higher in self-esteem than those in 1986. Combined with some previous studies finding significant increases in self-esteem and positive self-views over time, these results suggest that cultural change in the form of cohort and time period cannot be ignored as influences in cross-sectional and longitudinal studies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Development and validation of visceral fat quantification as a surrogate marker for differentiation of Crohn's disease and intestinal tuberculosis.

PubMed

Yadav, Dawesh Prakash; Madhusudhan, Kumble Seetharama; Kedia, Saurabh; Sharma, Raju; Pratap Mouli, Venigalla; Bopanna, Sawan; Dhingra, Rajan; Pradhan, Rajesh; Goyal, Sandeep; Sreenivas, Vishnubhatla; Vikram, Naval K; Makharia, Govind; Ahuja, Vineet

2017-02-01

Crohn's disease (CD) and intestinal tuberculosis (ITB) have close phenotypic resemblance. Mesenteric fat (a component of visceral fat [VF]) hypertrophy and fat wrapping, which is visible radiologically as fibrofatty proliferation, is seen more commonly in CD than in ITB. The present study was conducted to study the role of VF in differentiating CD and ITB. Visceral fat area and subcutaneous (SC) fat area were measured on computed tomography in two cohorts (development and validation). VF/SC ratio was also calculated for all patients. In the development cohort, retrospective data collection was carried out for 75 patients with CD and ITB who were on follow-up from January 2012 to November 2014. In the validation cohort, 82 patients were recruited prospectively from December 2014 to December 2015 and were diagnosed as CD or ITB according to standard diagnostic criteria. Visceral fat area and VF/SC ratio were significantly higher in CD patients (n = 42: development, n = 46: validation) than in ITB patients (n = 33: development, n = 36: validation) in both the development (106.2 ± 63.5 vs 37.3 ± 22, P = <0.001; 1.1 ± 0.57 vs 0.43 ± 0.24, P = <0.001) and validation cohorts (102.2 ± 69.8 vs 55.8 ± 44.9, P = 0.01; 1.2 ± 0.68 vs 0.56 ± 0.33, P = <0.001). A cut-off of 0.63 for VF/SC ratio in the development cohort had a high sensitivity (82%) and specificity (81%) in differentiating CD and ITB. Similar sensitivity (81%) and specificity (78%) were seen when this cut-off was applied in the validation cohort. The VF/SC ratio is a simple, cost-effective, non-invasive and single objective parameter with a good sensitivity and specificity to differentiate CD and ITB. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

A prospectively validated nomogram for predicting the risk of chemotherapy-induced febrile neutropenia: a multicenter study.

PubMed

Bozcuk, H; Yıldız, M; Artaç, M; Kocer, M; Kaya, Ç; Ulukal, E; Ay, S; Kılıç, M P; Şimşek, E H; Kılıçkaya, P; Uçar, S; Coskun, H S; Savas, B

2015-06-01

There is clinical need to predict risk of febrile neutropenia before a specific cycle of chemotherapy in cancer patients. Data on 3882 chemotherapy cycles in 1089 consecutive patients with lung, breast, and colon cancer from four teaching hospitals were used to construct a predictive model for febrile neutropenia. A final nomogram derived from the multivariate predictive model was prospectively confirmed in a second cohort of 960 consecutive cases and 1444 cycles. The following factors were used to construct the nomogram: previous history of febrile neutropenia, pre-cycle lymphocyte count, type of cancer, cycle of current chemotherapy, and patient age. The predictive model had a concordance index of 0.95 (95 % confidence interval (CI) = 0.91-0.99) in the derivation cohort and 0.85 (95 % CI = 0.80-0.91) in the external validation cohort. A threshold of 15 % for the risk of febrile neutropenia in the derivation cohort was associated with a sensitivity of 0.76 and specificity of 0.98. These figures were 1.00 and 0.49 in the validation cohort if a risk threshold of 50 % was chosen. This nomogram is helpful in the prediction of febrile neutropenia after chemotherapy in patients with lung, breast, and colon cancer. Usage of this nomogram may help decrease the morbidity and mortality associated with febrile neutropenia and deserves further validation.

Validation of a Predictive Scoring System for Deep Sternal Wound Infection after Bilateral Internal Thoracic Artery Grafting in a Cohort of French Patients.

PubMed

Perrotti, Andrea; Gatti, Giuseppe; Dorigo, Enrica; Sinagra, Gianfranco; Pappalardo, Aniello; Chocron, Sidney

The Gatti score is a weighted scoring system based on risk factors for deep sternal wound infection (DSWI) that was created in an Italian center to predict DSWI risk after bilateral internal thoracic artery (BITA) grafting. No external evaluation based on validation samples derived from other surgical centers has been performed. The aim of this study is to perform this validation. During 2015, BITA grafts were used as skeletonized conduits in all 255 consecutive patients with multi-vessel coronary disease who underwent isolated coronary bypass surgery at the Department of Thoracic and Cardio-Vascular Surgery, University Hospital Jean Minjoz, Besançon, France. Baseline characteristics, operative data, and immediate outcomes of every patient were collected prospectively. A DSWI risk score was assigned to each patient pre-operatively. The discrimination power of both models, pre-operative and combined, of the Gatti score was assessed with the calculation of the area under the receiver operating characteristic curve. Fourteen (5.5%) patients had DSWI. Major differences both as the baseline characteristics of patients and surgical techniques were found between this series and the original series from which the Gatti score was derived. The area under the receiver operating characteristic curve was 0.78 (95% confidence interval: 0.64-0.92) for the pre-operative model and 0.84 (95% confidence interval: 0.69-0.98) for the combined model. The Gatti score has proven to be effective even in a cohort of French patients despite major differences from the original Italian series. Multi-center validation studies must be performed before introducing the score into clinical practice.

A novel accelerometer-based method to describe day-to-day exposure to potentially osteogenic vertical impacts in older adults: findings from a multi-cohort study.

PubMed

Hannam, K; Deere, K C; Hartley, A; Clark, E M; Coulson, J; Ireland, A; Moss, C; Edwards, M H; Dennison, E; Gaysin, T; Cooper, R; Wong, A; McPhee, J S; Cooper, C; Kuh, D; Tobias, J H

2017-03-01

This observational study assessed vertical impacts experienced in older adults as part of their day-to-day physical activity using accelerometry and questionnaire data. Population-based older adults experienced very limited high-impact activity. The accelerometry method utilised appeared to be valid based on comparisons between different cohorts and with self-reported activity. We aimed to validate a novel method for evaluating day-to-day higher impact weight-bearing physical activity (PA) in older adults, thought to be important in protecting against osteoporosis, by comparing results between four cohorts varying in age and activity levels, and with self-reported PA levels. Participants were from three population-based cohorts, MRC National Survey of Health and Development (NSHD), Hertfordshire Cohort Study (HCS) and Cohort for Skeletal Health in Bristol and Avon (COSHIBA), and the Master Athlete Cohort (MAC). Y-axis peaks (reflecting the vertical when an individual is upright) from a triaxial accelerometer (sampling frequency 50 Hz, range 0-16 g) worn at the waist for 7 days were classified as low (0.5-1.0 g), medium (1.0-1.5 g) or higher (≥1.5 g) impacts. There were a median of 90, 41 and 39 higher impacts/week in NSHD (age 69.5), COSHIBA (age 76.8) and HCS (age 78.5) participants, respectively (total n = 1512). In contrast, MAC participants (age 68.5) had a median of 14,322 higher impacts/week. In the three population cohorts combined, based on comparison of beta coefficients, moderate-high-impact activities as assessed by PA questionnaire were suggestive of stronger association with higher impacts from accelerometers (0.25 [0.17, 0.34]), compared with medium (0.18 [0.09, 0.27]) and low impacts (0.13 [0.07,0.19]) (beta coefficient, with 95 % CI). Likewise in MAC, reported moderate-high-impact activities showed a stronger association with higher impacts (0.26 [0.14, 0.37]), compared with medium (0.14 [0.05, 0.22]) and low impacts (0.03 [-0.02, 0

Validation of a screening tool for the rapid and reliable detection of CGG trinucleotide repeat expansions in FMR1.

PubMed

Basehore, Monica J; Marlowe, Natalia M; Jones, Julie R; Behlendorf, Deborah E; Laver, Thomas A; Friez, Michael J

2012-06-01

Most individuals with intellectual disability and/or autism are tested for Fragile X syndrome at some point in their lifetime. Greater than 99% of individuals with Fragile X have an expanded CGG trinucleotide repeat motif in the promoter region of the FMR1 gene, and diagnostic testing involves determining the size of the CGG repeat as well as methylation status when an expansion is present. Using a previously described triplet repeat-primed polymerase chain reaction, we have performed additional validation studies using two cohorts with previous diagnostic testing results available for comparison purposes. The first cohort (n=88) consisted of both males and females and had a high percentage of abnormal samples, while the second cohort (n=624) consisted of only females and was not enriched for expansion mutations. Data from each cohort were completely concordant with the results previously obtained during the course of diagnostic testing. This study further demonstrates the utility of using laboratory-developed triplet repeat-primed FMR1 testing in a clinical setting.

Retrospective cohort mortality study of workers at an aircraft maintenance facility. I. Epidemiological results.

PubMed

Spirtas, R; Stewart, P A; Lee, J S; Marano, D E; Forbes, C D; Grauman, D J; Pettigrew, H M; Blair, A; Hoover, R N; Cohen, J L

1991-08-01

. Hypothesis generating results are presented by a variety of exposures for causes of death not showing excesses in the overall cohort.

Genome-wide association analysis of metabolic traits in a birth cohort from a founder population.

PubMed

Sabatti, Chiara; Service, Susan K; Hartikainen, Anna-Liisa; Pouta, Anneli; Ripatti, Samuli; Brodsky, Jae; Jones, Chris G; Zaitlen, Noah A; Varilo, Teppo; Kaakinen, Marika; Sovio, Ulla; Ruokonen, Aimo; Laitinen, Jaana; Jakkula, Eveliina; Coin, Lachlan; Hoggart, Clive; Collins, Andrew; Turunen, Hannu; Gabriel, Stacey; Elliot, Paul; McCarthy, Mark I; Daly, Mark J; Järvelin, Marjo-Riitta; Freimer, Nelson B; Peltonen, Leena

2009-01-01

Genome-wide association studies (GWAS) of longitudinal birth cohorts enable joint investigation of environmental and genetic influences on complex traits. We report GWAS results for nine quantitative metabolic traits (triglycerides, high-density lipoprotein, low-density lipoprotein, glucose, insulin, C-reactive protein, body mass index, and systolic and diastolic blood pressure) in the Northern Finland Birth Cohort 1966 (NFBC1966), drawn from the most genetically isolated Finnish regions. We replicate most previously reported associations for these traits and identify nine new associations, several of which highlight genes with metabolic functions: high-density lipoprotein with NR1H3 (LXRA), low-density lipoprotein with AR and FADS1-FADS2, glucose with MTNR1B, and insulin with PANK1. Two of these new associations emerged after adjustment of results for body mass index. Gene-environment interaction analyses suggested additional associations, which will require validation in larger samples. The currently identified loci, together with quantified environmental exposures, explain little of the trait variation in NFBC1966. The association observed between low-density lipoprotein and an infrequent variant in AR suggests the potential of such a cohort for identifying associations with both common, low-impact and rarer, high-impact quantitative trait loci.

Validation results of specifications for motion control interoperability

NASA Astrophysics Data System (ADS)

Szabo, Sandor; Proctor, Frederick M.

1997-01-01

The National Institute of Standards and Technology (NIST) is participating in the Department of Energy Technologies Enabling Agile Manufacturing (TEAM) program to establish interface standards for machine tool, robot, and coordinate measuring machine controllers. At NIST, the focus is to validate potential application programming interfaces (APIs) that make it possible to exchange machine controller components with a minimal impact on the rest of the system. This validation is taking place in the enhanced machine controller (EMC) consortium and is in cooperation with users and vendors of motion control equipment. An area of interest is motion control, including closed-loop control of individual axes and coordinated path planning. Initial tests of the motion control APIs are complete. The APIs were implemented on two commercial motion control boards that run on two different machine tools. The results for a baseline set of APIs look promising, but several issues were raised. These include resolving differing approaches in how motions are programmed and defining a standard measurement of performance for motion control. This paper starts with a summary of the process used in developing a set of specifications for motion control interoperability. Next, the EMC architecture and its classification of motion control APIs into two classes, Servo Control and Trajectory Planning, are reviewed. Selected APIs are presented to explain the basic functionality and some of the major issues involved in porting the APIs to other motion controllers. The paper concludes with a summary of the main issues and ways to continue the standards process.

A retrospective cohort study of suspected child maltreatment cases resulting in hospitalization.

PubMed

Friedman, Lee S; Sheppard, Shirley; Friedman, Daniel

2012-11-01

Although the incidence and risk factors of child abuse have been well researched, there continues to be a need for large studies that provide information regarding the process of recognizing children whose health and lives are most seriously threatened by abuse and neglect, in particular children requiring hospitalization as a result of child abuse. The purpose of this study was to (1) describe differences in the type of injuries and illnesses of children hospitalized for abuse and neglect and (2) assess the relationship between in-hospital mortality and child maltreatment. For this retrospective cohort study, child maltreatment cases were identified using medical record databases of patients treated in all hospitals and trauma units in Illinois. A comparison group of children not suffering from suspected maltreatment were randomly selected and matched by age and data source to the suspected maltreatment cases. 2656 children under the age of 13 years suspected of suffering maltreatment who were admitted to any hospital in Illinois between 2000 and 2009. The analysis showed distinct patterns in injury, physical illness and psychological disorders for each subgroup of maltreatment cases. Among the cases of maltreatment 75.6% were discharged home, 2.9% into child protective services and 15.8% to an intermediate care facility. In the final multivariable conditional logistic regression model, children suffering maltreatment continued to have a higher odds of dying during hospitalization (adjusted OR=2.99; CI95%: 1.63, 5.45; p<0.001). There were distinct diagnostic patterns and outcomes among suspected cases of child maltreatment admitted to Illinois hospitals over a 10-year period. This large retrospective cohort study confirms findings reported in many smaller studies and larger national cross-sectional surveys. Copyright © 2012 Elsevier Ltd. All rights reserved.

Fast track pathway reduces sight loss in giant cell arteritis: results of a longitudinal observational cohort study.

PubMed

Patil, P; Williams, M; Maw, W W; Achilleos, K; Elsideeg, S; Dejaco, C; Borg, F; Gupta, S; Dasgupta, B

2015-01-01

To investigate the effectiveness of a fast track pathway (FTP) on sight loss in patients with suspected giant cell arteritis (GCA). A longitudinal observational cohort study was conducted in the secondary care rheumatology department. One hundred and thirty-five newly referred suspected GCA patients seen via the FTP (Jan. 2012-Dec. 2013) were compared to 81 patients seen through the conventional referral and review system (Jan. 2009-Dec. 2011). The FTP resulted in significant reduction in irreversible sight loss from 37.0% (as seen in the historical cohort 2009-2011) to 9.0 % (2012-2013, OR 0.17, p=0.001). Adjustment for clinical and demographic parameters including known risk factors for GCA associated blindness did not significantly change the primary result (OR 0.08, p=0.001). FTP resulted in a reduction of time from symptom onset to diagnosis, particularly by reduction of time from general practitioner's (GP) referral to the rheumatology review (79% of FTP patients were seen within one working day compared to 64.6 % in the conventional pathway, p=0.023). The FTP has seen a reduction in number of GP appointments. There was a significant reduction of permanent sight loss with a fast track GCA pathway. The effect may be due to multiple factors including better GP education and reduction in delayed diagnosis. These results need verification at other sites.

Validation of microbiological testing in cardiovascular tissue banks: results of a quality round trial.

PubMed

de By, Theo M M H; McDonald, Carl; Süßner, Susanne; Davies, Jill; Heng, Wee Ling; Jashari, Ramadan; Bogers, Ad J J C; Petit, Pieter

2017-11-01

Surgeons needing human cardiovascular tissue for implantation in their patients are confronted with cardiovascular tissue banks that use different methods to identify and decontaminate micro-organisms. To elucidate these differences, we compared the quality of processing methods in 20 tissue banks and 1 reference laboratory. We did this to validate the results for accepting or rejecting tissue. We included the decontamination methods used and the influence of antibiotic cocktails and residues with results and controls. The minor details of the processes were not included. To compare the outcomes of microbiological testing and decontamination methods of heart valve allografts in cardiovascular tissue banks, an international quality round was organized. Twenty cardiovascular tissue banks participated in this quality round. The quality round method was validated first and consisted of sending purposely contaminated human heart valve tissue samples with known micro-organisms to the participants. The participants identified the micro-organisms using their local decontamination methods. Seventeen of the 20 participants correctly identified the micro-organisms; if these samples were heart valves to be released for implantation, 3 of the 20 participants would have decided to accept their result for release. Decontamination was shown not to be effective in 13 tissue banks because of growth of the organisms after decontamination. Articles in the literature revealed that antibiotics are effective at 36°C and not, or less so, at 2-8°C. The decontamination procedure, if it is validated, will ensure that the tissue contains no known micro-organisms. This study demonstrates that the quality round method of sending contaminated tissues and assessing the results of the microbiological cultures is an effective way of validating the processes of tissue banks. Only when harmonization, based on validated methods, has been achieved, will surgeons be able to fully rely on the methods

Smoking and Mortality in Eastern Europe: Results From the PrivMort Retrospective Cohort Study of 177 376 Individuals.

PubMed

Stefler, Denes; Murphy, Michael; Irdam, Darja; Horvat, Pia; Jarvis, Martin; King, Lawrence; McKee, Martin; Bobak, Martin

2018-05-03

The estimated prevalence of smoking and proportion of deaths due to tobacco in Eastern European countries are among the highest in the world. Existing estimates of mortality attributable to smoking in the region are mostly indirect. The aim of this analysis was to calculate the proportion of tobacco-attributed deaths in three Eastern European countries using individual level cohort data. The PrivMort project established a cohort of relatives of participants in population sample surveys in Russia, Belarus and Hungary. Survey participants provided data on smoking habits and vital statistics of their close relatives between 1982 and 2013. Population attributable risk fractions (PARF) in men (n = 99528) and women (n = 77848) aged 40-79 years were calculated from the prevalence rates of smoking and hazard ratios of mortality for smokers versus non-smokers. Trends in PARF over four 8-year time periods (1982-1989, 1990-1997, 1998-2005, and 2006-2013) were examined. In men in the most recent period (2006-2013), the proportions of deaths attributable to tobacco were 23% in Russia, 22% in Belarus, and 22% in Hungary. The respective estimates in women were lower (2%, 2%, and 13%), possibly due to underestimation of smoking prevalence. PARF estimates have declined slightly since the early 1990s in men but increased in women. Consistently with existing indirect estimates, our results based on individual level cohort data suggest that over one fifth of all deaths in men aged 40-79 years are attributable to tobacco. While these proportions are lower in women, the increasing trend is a major concern. This is the first large scale, individual-level cohort study that estimated the mortality attributable to tobacco smoking directly in Eastern European population samples. The results confirm previous indirect estimates and show that more than 20% of all deaths in Eastern European men can be attributed to tobacco. The study also confirms the increasing trend in smoking-related deaths

Validation of the Framingham general cardiovascular risk score in a multiethnic Asian population: a retrospective cohort study.

PubMed

Chia, Yook Chin; Gray, Sarah Yu Weng; Ching, Siew Mooi; Lim, Hooi Min; Chinna, Karuthan

2015-05-19

This study aims to examine the validity of the Framingham general cardiovascular disease (CVD) risk chart in a primary care setting. This is a 10-year retrospective cohort study. A primary care clinic in a teaching hospital in Malaysia. 967 patients' records were randomly selected from patients who were attending follow-up in the clinic. Baseline demographic data, history of diabetes and smoking, blood pressure (BP), and serum lipids were captured from patient records in 1998. Each patient's Framingham CVD score was computed from these parameters. All atherosclerotic CVD events occurring between 1998 and 2007 were counted. In 1998, mean age was 57 years with 33.8% men, 6.1% smokers, 43.3% diabetics and 59.7% hypertensive. Median BP was 140/80 mm Hg and total cholesterol 6.0 mmol/L (1.3). The predicted median Framingham general CVD risk score for the study population was 21.5% (IQR 1.2-30.0) while the actual CVD events that occurred in the 10 years was 13.1% (127/967). The median CVD points for men was 30.0, giving them a CVD risk of more than 30%; for women it is 18.5, a CVD risk of 21.5%. Our study found that the Framingham general CVD risk score to have moderate discrimination with an area under the receiver operating characteristic curve (AUC) of 0.63. It also discriminates well for Malay (AUC 0.65, p=0.01), Chinese (AUC 0.60, p=0.03), and Indians (AUC 0.65, p=0.001). There was good calibration with Hosmer-Lemeshow test χ(2)=3.25, p=0.78. Taking into account that this cohort of patients were already on treatment, the Framingham General CVD Risk Prediction Score predicts fairly accurately for men and overestimates somewhat for women. In the absence of local risk prediction charts, the Framingham general CVD risk prediction chart is a reasonable alternative for use in a multiethnic group in a primary care setting. 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.

Derivation and Internal Validation of a Clinical Prediction Tool for 30-Day Mortality in Lower Gastrointestinal Bleeding.

PubMed

Sengupta, Neil; Tapper, Elliot B

2017-05-01

There are limited data to predict which patients with lower gastrointestinal bleeding are at risk for adverse outcomes. We aimed to develop a clinical tool based on admission variables to predict 30-day mortality in lower gastrointestinal bleeding. We used a validated machine learning algorithm to identify adult patients hospitalized with lower gastrointestinal bleeding at an academic medical center between 2008 and 2015. The cohort was split randomly into derivation and validation cohorts. In the derivation cohort, we used multiple logistic regression on all candidate admission variables to create a prediction model for 30-day mortality, using area under the receiving operator characteristic curve and misclassification rate to estimate prediction accuracy. Regression coefficients were used to derive an integer score, and mortality risk associated with point totals was assessed. In the derivation cohort (n = 4044), 8 variables were most associated with 30-day mortality: age, dementia, metastatic cancer, chronic kidney disease, chronic pulmonary disease, anticoagulant use, admission hematocrit, and albumin. The model yielded a misclassification rate of 0.06 and area under the curve of 0.81. The integer score ranged from -10 to 26 in the derivation cohort, with a misclassification rate of 0.11 and area under the curve of 0.74. In the validation cohort (n = 2060), the score had an area under the curve of 0.72 with a misclassification rate of 0.12. After dividing the score into 4 quartiles of risk, 30-day mortality in the derivation and validation sets was 3.6% and 4.4% in quartile 1, 4.9% and 7.3% in quartile 2, 9.9% and 9.1% in quartile 3, and 24% and 26% in quartile 4, respectively. A clinical tool can be used to predict 30-day mortality in patients hospitalized with lower gastrointestinal bleeding. Copyright © 2017 Elsevier Inc. All rights reserved.

Results from an Independent View on The Validation of Safety-Critical Space Systems

NASA Astrophysics Data System (ADS)

Silva, N.; Lopes, R.; Esper, A.; Barbosa, R.

2013-08-01

The Independent verification and validation (IV&V) has been a key process for decades, and is considered in several international standards. One of the activities described in the “ESA ISVV Guide” is the independent test verification (stated as Integration/Unit Test Procedures and Test Data Verification). This activity is commonly overlooked since customers do not really see the added value of checking thoroughly the validation team work (could be seen as testing the tester's work). This article presents the consolidated results of a large set of independent test verification activities, including the main difficulties, results obtained and advantages/disadvantages for the industry of these activities. This study will support customers in opting-in or opting-out for this task in future IV&V contracts since we provide concrete results from real case studies in the space embedded systems domain.

[Willingness to accept an Internet-based mobility platform in different age cohorts. Empiric results of the project S-Mobil 100].

PubMed

Beil, J; Cihlar, V; Kruse, A

2015-02-01

The aim of the project S-Mobil 100 is to develop and implement a prototype of an internet-based, generation-appropriate mobility platform in the model region Siegen-Wittgenstein. In the context of an empirical preliminary study, use of technology, experience with technology, general attitudes towards technology, general technology commitment, and the willingness to accept the mobility platform were investigated in different age cohorts. The investigation was carried out using a written survey based on a standardized questionnaire. The sample of 358 persons aged 40-90 years was divided in four age cohorts (40-54, 55-64, 65-74, and 75 + years). Our results show a high willingness to accept the mobility platform in the overall sample. Age, residence, income, and general technology commitment were significant predictors for the judgment of the platform. Although there were group differences in accepting the mobility platform, the older cohorts are also open-minded towards this new technology.

Individualized prediction of perineural invasion in colorectal cancer: development and validation of a radiomics prediction model.

PubMed

Huang, Yanqi; He, Lan; Dong, Di; Yang, Caiyun; Liang, Cuishan; Chen, Xin; Ma, Zelan; Huang, Xiaomei; Yao, Su; Liang, Changhong; Tian, Jie; Liu, Zaiyi

2018-02-01

To develop and validate a radiomics prediction model for individualized prediction of perineural invasion (PNI) in colorectal cancer (CRC). After computed tomography (CT) radiomics features extraction, a radiomics signature was constructed in derivation cohort (346 CRC patients). A prediction model was developed to integrate the radiomics signature and clinical candidate predictors [age, sex, tumor location, and carcinoembryonic antigen (CEA) level]. Apparent prediction performance was assessed. After internal validation, independent temporal validation (separate from the cohort used to build the model) was then conducted in 217 CRC patients. The final model was converted to an easy-to-use nomogram. The developed radiomics nomogram that integrated the radiomics signature and CEA level showed good calibration and discrimination performance [Harrell's concordance index (c-index): 0.817; 95% confidence interval (95% CI): 0.811-0.823]. Application of the nomogram in validation cohort gave a comparable calibration and discrimination (c-index: 0.803; 95% CI: 0.794-0.812). Integrating the radiomics signature and CEA level into a radiomics prediction model enables easy and effective risk assessment of PNI in CRC. This stratification of patients according to their PNI status may provide a basis for individualized auxiliary treatment.

A novel early risk assessment tool for detecting clinical outcomes in patients with heat-related illness (J-ERATO score): Development and validation in independent cohorts in Japan.

PubMed

Hayashida, Kei; Kondo, Yutaka; Hifumi, Toru; Shimazaki, Junya; Oda, Yasutaka; Shiraishi, Shinichiro; Fukuda, Tatsuma; Sasaki, Junichi; Shimizu, Keiki

2018-01-01

We sought to develop a novel risk assessment tool to predict the clinical outcomes after heat-related illness. Prospective, multicenter observational study. Patients who transferred to emergency hospitals in Japan with heat-related illness were registered. The sample was divided into two parts: 60% to construct the score and 40% to validate it. A binary logistic regression model was used to predict hospital admission as a primary outcome. The resulting model was transformed into a scoring system. A total of 3,001 eligible patients were analyzed. There was no difference in variables between development and validation cohorts. Based on the result of a logistic regression model in the development phase (n = 1,805), the J-ERATO score was defined as the sum of the six binary components in the prehospital setting (respiratory rate≥22 /min, Glasgow coma scale<15, systolic blood pressure≤100 mmHg, heart rate≥100 bpm, body temperature≥38°C, and age≥65 y), for a total score ranging from 0 to 6. In the validation phase (n = 1,196), the score had excellent discrimination (C-statistic 0.84; 95% CI 0.79-0.89, p<0.0001) and calibration (P>0.2 by Hosmer-Lemeshow test). The observed proportion of hospital admission increased with increasing J-ERATO score (score = 0, 5.0%; score = 1, 15.0%; score = 2, 24.6%; score = 3, 38.6%; score = 4, 68.0%; score = 5, 85.2%; score = 6, 96.4%). Multivariate analyses showed that the J-ERATO score was an independent positive predictor of hospital admission (adjusted OR, 2.43; 95% CI, 2.06-2.87; P<0.001), intensive care unit (ICU) admission (3.73; 2.95-4.72; P<0.001) and in-hospital mortality (1.65; 1.18-2.32; P = 0.004). The J-ERATO score is simply assessed and can facilitate the identification of patients with higher risk of heat-related hospitalization. This scoring system is also significantly associated with the higher likelihood of ICU admission and in-hospital mortality after heat-related hospitalization.

Cohort profile: the Spanish WORKing life Social Security (WORKss) cohort study.

PubMed

López Gómez, María Andrée; Durán, Xavier; Zaballa, Elena; Sanchez-Niubo, Albert; Delclos, George L; Benavides, Fernando G

2016-03-07

The global economy is changing the labour market and social protection systems in Europe. The effect of both changes on health needs to be monitored in view of an ageing population and the resulting increase in prevalence of chronic health conditions. The Spanish WORKing life Social Security (WORKss) cohort study provides unique longitudinal data to study the impact of labour trajectories and employment conditions on health, in terms of sickness absence, permanent disability and death. The WORKss cohort originated from the Continuous Working Life Sample (CWLS) generated by the General Directorate for the Organization of the Social Security in Spain. The CWLS contains a 4% representative sample of all individuals in contact with the Social Security system. The WORKss cohort exclusively includes individuals with a labour trajectory from 1981 or later. In 2004, the cohort was initiated with 1,022 ,79 Social Security members: 840,770 (82.2%) contributors and 182,009 (17.8%) beneficiaries aged 16 and older. The WORKss cohort includes demographic characteristics, chronological data about employment history, retirement, permanent disability and death. These data make possible the measurement of incidence of permanent disability, the number of potential years of working life lost, and the number of contracts and inactive periods with the Social Security system. The WORKss cohort was linked to temporary sickness absence registries to study medical diagnoses that lead to permanent disability and consequently to an earlier exit from the labour market in unhealthy conditions. Thanks to its administrative source, the WORKss cohort study will continue follow-up in the coming years, keeping the representativeness of the Spanish population affiliated to the Social Security system. The linkage between the WORKss cohort and temporary sickness absence registries is envisioned to continue. Future plans include the linkage of the cohort with mortality registries. Published by the BMJ

Using full-cohort data in nested case-control and case-cohort studies by multiple imputation.

PubMed

Keogh, Ruth H; White, Ian R

2013-10-15

In many large prospective cohorts, expensive exposure measurements cannot be obtained for all individuals. Exposure-disease association studies are therefore often based on nested case-control or case-cohort studies in which complete information is obtained only for sampled individuals. However, in the full cohort, there may be a large amount of information on cheaply available covariates and possibly a surrogate of the main exposure(s), which typically goes unused. We view the nested case-control or case-cohort study plus the remainder of the cohort as a full-cohort study with missing data. Hence, we propose using multiple imputation (MI) to utilise information in the full cohort when data from the sub-studies are analysed. We use the fully observed data to fit the imputation models. We consider using approximate imputation models and also using rejection sampling to draw imputed values from the true distribution of the missing values given the observed data. Simulation studies show that using MI to utilise full-cohort information in the analysis of nested case-control and case-cohort studies can result in important gains in efficiency, particularly when a surrogate of the main exposure is available in the full cohort. In simulations, this method outperforms counter-matching in nested case-control studies and a weighted analysis for case-cohort studies, both of which use some full-cohort information. Approximate imputation models perform well except when there are interactions or non-linear terms in the outcome model, where imputation using rejection sampling works well. Copyright © 2013 John Wiley & Sons, Ltd.

Self-reported short sleep duration and insomnia symptoms as predictors of post-pregnancy weight change: Results from a cohort study

PubMed Central

Rognmo, Kamilla; Sivertsen, Børge; Eberhard-Gran, Malin

2016-01-01

This study aims to investigate whether change in sleep duration and insomnia symptoms in the postpartum period is related to change in body mass index from before to 2 years after pregnancy. This study is based on self-report data from a Norwegian cohort, the AHUS Birth Cohort Study. Data were collected at 8 weeks (T1) and 2 years (T2) postpartum. Data from 812 women were analyzed. The results showed that only women with symptoms of insomnia at both T1 and T2 (persistent symptoms) had a greater increase in body mass index compared to women with no insomnia symptoms at T1 or T2.The results indicate that persistent insomnia symptoms are related to a greater increase in body mass index. PMID:27634975

LONG TERM RESULTS AFTER STAPLED HEMORRHOIDOPEXY ALONE AND COMPLEMENTED BY EXCISIONAL HEMORRHOIDECTOMY: A RETROSPECTIVE COHORT STUDY

PubMed Central

ARAUJO, Sergio Eduardo Alonso; HORCEL, Lucas de Araujo; SEID, Victor Edmond; BERTONCINI, Alexandre Bruno; KLAJNER, Sidney

2016-01-01

ABSTRACT Background: Stapled hemorrhoidopexy is associated with less postoperative pain and faster recovery. However, it may be associated with a greater risk of symptomatic recurrence. We hypothesized that undertaking a limited surgical excision of hemorrhoid disease after stapling may be a valid approach for selected patients. Aim: To compare long-term results after stapled hemorrhoidopexy with and without complementation with closed excisional technique. Method: In a retrospective uni-institutional cohort study, sixty-five (29 men) patients underwent stapled hemorrhoidopexy and 21 (13 men) underwent stapled hemorrhoidopexy with excision. The same surgeons operated on all cases. Patients underwent stapled hemorrhoidectomy associated with excisional surgery if symptoms attributable to external hemorrhoid piles were observed preoperatively, or if residual prolapse or bulky external disease was observed after the firing of the stapler. A closed excisional diathermy hemorrhoidectomy without vascular ligation was utilized in all complemented cases. All clinical variables were obtained from a questionnaire evaluation obtained through e-mail, telephone interview, or office follow-up. Results: The median duration of postoperative follow-up was 48.5 (6-40) months. Patients with grades 3 and 4 hemorrhoid disease were operated on more frequently using stapled hemorrhoidopexy complemented with excisional technique (95.2% vs. 55.4%, p=0.001). Regarding respectively stapled hemorrhoidopexy and stapled hemorrhoidopexy complemented with excision, there was no difference between the techniques in relation to symptom recurrence (43% and 33%, p=0.45) and median interval between surgery and symptom recurrence (30 (8-84) and 38.8 (8-65) months, p=0.80). Eight (12.3%) patients were re-operated after stapled hemorrhoidopexy and 2 (9.6%), after hemorrhoidopexy with excision (p=0.78). Patient distribution in both groups according to the degree of postoperative satisfaction was similar (p

Creation of a pediatric mature B-cell non-Hodgkin lymphoma cohort within the Pediatric Health Information System Database.

PubMed

Citrin, Rebecca; Horowitz, Joseph P; Reilly, Anne F; Li, Yimei; Huang, Yuan-Shung; Getz, Kelly D; Seif, Alix E; Fisher, Brian T; Aplenc, Richard

2017-01-01

Mature B-cell non-Hodgkin lymphoma (B-NHL) constitutes a collection of relatively rare pediatric malignancies. In order to utilize administrative data to perform large-scale epidemiologic studies within this population, a two-step process was used to assemble a 12-year cohort of B-NHL patients treated between 2004 and 2015 within the Pediatric Health Information System database. Patients were identified by ICD-9 codes, and their chemotherapy data were then manually reviewed against standard B-NHL treatment regimens. A total of 1,409 patients were eligible for cohort inclusion. This process was validated at a single center, utilizing both an institutional tumor registry and medical record review as the gold standards. The validation demonstrated appropriate sensitivity (91.5%) and positive predictive value (95.1%) to allow for the future use of this cohort for epidemiologic and comparative effectiveness research.

Validating SPICES as a Screening Tool for Frailty Risks among Hospitalized Older Adults

PubMed Central

Aronow, Harriet Udin; Borenstein, Jeff; Haus, Flora; Braunstein, Glenn D.; Bolton, Linda Burnes

2014-01-01

Older patients are vulnerable to adverse hospital events related to frailty. SPICES, a common screening protocol to identify risk factors in older patients, alerts nurses to initiate care plans to reduce the probability of patient harm. However, there is little published validating the association between SPICES and measures of frailty and adverse outcomes. This paper used data from a prospective cohort study on frailty among 174 older adult inpatients to validate SPICES. Almost all patients met one or more SPICES criteria. The sum of SPICES was significantly correlated with age and other well-validated assessments for vulnerability, comorbid conditions, and depression. Individuals meeting two or more SPICES criteria had a risk of adverse hospital events three times greater than individuals with either no or one criterion. Results suggest that as a screening tool used within 24 hours of admission, SPICES is both valid and predictive of adverse events. PMID:24876954

42 CFR 476.85 - Conclusive effect of QIO initial denial determinations and changes as a result of DRG validations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... determinations and changes as a result of DRG validations. 476.85 Section 476.85 Public Health CENTERS FOR... denial determinations and changes as a result of DRG validations. A QIO initial denial determination or change as a result of DRG validation is final and binding unless, in accordance with the procedures in...

42 CFR 476.85 - Conclusive effect of QIO initial denial determinations and changes as a result of DRG validations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... determinations and changes as a result of DRG validations. 476.85 Section 476.85 Public Health CENTERS FOR... denial determinations and changes as a result of DRG validations. A QIO initial denial determination or change as a result of DRG validation is final and binding unless, in accordance with the procedures in...

42 CFR 476.85 - Conclusive effect of QIO initial denial determinations and changes as a result of DRG validations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... determinations and changes as a result of DRG validations. 476.85 Section 476.85 Public Health CENTERS FOR... denial determinations and changes as a result of DRG validations. A QIO initial denial determination or change as a result of DRG validation is final and binding unless, in accordance with the procedures in...

Cohort profile: the Geoscience and Health Cohort Consortium (GECCO) in the Netherlands

PubMed Central

Timmermans, Erik J; Lakerveld, Jeroen; Beulens, Joline W J; Boomsma, Dorret I; Kramer, Sophia E; Oosterman, Mirjam; Willemsen, Gonneke; Stam, Mariska; Nijpels, Giel; Schuengel, Carlo; Smit, Jan H; Brunekreef, Bert; Dekkers, Jasper E C; Deeg, Dorly J H; Penninx, Brenda W J H; Huisman, Martijn

2018-01-01

Purpose In the Netherlands, a great variety of objectively measured geo-data is available, but these data are scattered and measured at varying spatial and temporal scales. The centralisation of these geo-data and the linkage of these data to individual-level data from longitudinal cohort studies enable large-scale epidemiological research on the impact of the environment on public health in the Netherlands. In the Geoscience and Health Cohort Consortium (GECCO), six large-scale and ongoing cohort studies have been enriched with a variety of existing geo-data. Here, we introduce GECCO by describing: (1) the phenotypes of the involved cohort studies, (2) the collected geo-data and their sources, (3) the methodology that was used to link the collected geo-data to individual cohort studies, (4) the similarity of commonly used geo-data between our consortium and the nationwide situation in the Netherlands and (5) the distribution of geo-data within our consortium. Participants GECCO includes participants from six prospective cohort studies (eg, 44 657 respondents (18–100 years) in 2006) and it covers all municipalities in the Netherlands. Using postal code information of the participants, geo-data on the address-level, postal code-level as well as neighbourhood-level could be linked to individual-level cohort data. Findings to date The geo-data could be successfully linked to almost all respondents of all cohort studies, with successful data-linkage rates ranging from 97.1% to 100.0% between cohort studies. The results show variability in geo-data within and across cohorts. GECCO increases power of analyses, provides opportunities for cross-checking and replication, ensures sufficient geographical variation in environmental determinants and allows for nuanced analyses on specific subgroups. Future plans GECCO offers unique opportunities for (longitudinal) studies on the complex relationships between the environment and health outcomes. For example, GECCO will be

Cohort profile: the Geoscience and Health Cohort Consortium (GECCO) in the Netherlands.

PubMed

Timmermans, Erik J; Lakerveld, Jeroen; Beulens, Joline W J; Boomsma, Dorret I; Kramer, Sophia E; Oosterman, Mirjam; Willemsen, Gonneke; Stam, Mariska; Nijpels, Giel; Schuengel, Carlo; Smit, Jan H; Brunekreef, Bert; Dekkers, Jasper E C; Deeg, Dorly J H; Penninx, Brenda W J H; Huisman, Martijn

2018-06-09

In the Netherlands, a great variety of objectively measured geo-data is available, but these data are scattered and measured at varying spatial and temporal scales. The centralisation of these geo-data and the linkage of these data to individual-level data from longitudinal cohort studies enable large-scale epidemiological research on the impact of the environment on public health in the Netherlands. In the Geoscience and Health Cohort Consortium (GECCO), six large-scale and ongoing cohort studies have been enriched with a variety of existing geo-data. Here, we introduce GECCO by describing: (1) the phenotypes of the involved cohort studies, (2) the collected geo-data and their sources, (3) the methodology that was used to link the collected geo-data to individual cohort studies, (4) the similarity of commonly used geo-data between our consortium and the nationwide situation in the Netherlands and (5) the distribution of geo-data within our consortium. GECCO includes participants from six prospective cohort studies (eg, 44 657 respondents (18-100 years) in 2006) and it covers all municipalities in the Netherlands. Using postal code information of the participants, geo-data on the address-level, postal code-level as well as neighbourhood-level could be linked to individual-level cohort data. The geo-data could be successfully linked to almost all respondents of all cohort studies, with successful data-linkage rates ranging from 97.1% to 100.0% between cohort studies. The results show variability in geo-data within and across cohorts. GECCO increases power of analyses, provides opportunities for cross-checking and replication, ensures sufficient geographical variation in environmental determinants and allows for nuanced analyses on specific subgroups. GECCO offers unique opportunities for (longitudinal) studies on the complex relationships between the environment and health outcomes. For example, GECCO will be used for further research on environmental determinants

Development and validation of an ICD-10-based disability predictive index for patients admitted to hospitals with trauma.

PubMed

Wada, Tomoki; Yasunaga, Hideo; Yamana, Hayato; Matsui, Hiroki; Fushimi, Kiyohide; Morimura, Naoto

2018-03-01

There was no established disability predictive measurement for patients with trauma that could be used in administrative claims databases. The aim of the present study was to develop and validate a diagnosis-based disability predictive index for severe physical disability at discharge using the International Classification of Diseases, 10th revision (ICD-10) coding. This retrospective observational study used the Diagnosis Procedure Combination database in Japan. Patients who were admitted to hospitals with trauma and discharged alive from 01 April 2010 to 31 March 2015 were included. Pediatric patients under 15 years old were excluded. Data for patients admitted to hospitals from 01 April 2010 to 31 March 2013 was used for development of a disability predictive index (derivation cohort), while data for patients admitted to hospitals from 01 April 2013 to 31 March 2015 was used for the internal validation (validation cohort). The outcome of interest was severe physical disability defined as the Barthel Index score of <60 at discharge. Trauma-related ICD-10 codes were categorized into 36 injury groups with reference to the categorization used in the Global Burden of Diseases study 2013. A multivariable logistic regression analysis was performed for the outcome using the injury groups and patient baseline characteristics including patient age, sex, and Charlson Comorbidity Index (CCI) score in the derivation cohort. A score corresponding to a regression coefficient was assigned to each injury group. The disability predictive index for each patient was defined as the sum of the scores. The predictive performance of the index was validated using the receiver operating characteristic curve analysis in the validation cohort. The derivation cohort included 1,475,158 patients, while the validation cohort included 939,659 patients. Of the 939,659 patients, 235,382 (25.0%) were discharged with severe physical disability. The c-statistics of the disability predictive index

Validation of electronic medical record-based phenotyping algorithms: results and lessons learned from the eMERGE network.

PubMed

Newton, Katherine M; Peissig, Peggy L; Kho, Abel Ngo; Bielinski, Suzette J; Berg, Richard L; Choudhary, Vidhu; Basford, Melissa; Chute, Christopher G; Kullo, Iftikhar J; Li, Rongling; Pacheco, Jennifer A; Rasmussen, Luke V; Spangler, Leslie; Denny, Joshua C

2013-06-01

Genetic studies require precise phenotype definitions, but electronic medical record (EMR) phenotype data are recorded inconsistently and in a variety of formats. To present lessons learned about validation of EMR-based phenotypes from the Electronic Medical Records and Genomics (eMERGE) studies. The eMERGE network created and validated 13 EMR-derived phenotype algorithms. Network sites are Group Health, Marshfield Clinic, Mayo Clinic, Northwestern University, and Vanderbilt University. By validating EMR-derived phenotypes we learned that: (1) multisite validation improves phenotype algorithm accuracy; (2) targets for validation should be carefully considered and defined; (3) specifying time frames for review of variables eases validation time and improves accuracy; (4) using repeated measures requires defining the relevant time period and specifying the most meaningful value to be studied; (5) patient movement in and out of the health plan (transience) can result in incomplete or fragmented data; (6) the review scope should be defined carefully; (7) particular care is required in combining EMR and research data; (8) medication data can be assessed using claims, medications dispensed, or medications prescribed; (9) algorithm development and validation work best as an iterative process; and (10) validation by content experts or structured chart review can provide accurate results. Despite the diverse structure of the five EMRs of the eMERGE sites, we developed, validated, and successfully deployed 13 electronic phenotype algorithms. Validation is a worthwhile process that not only measures phenotype performance but also strengthens phenotype algorithm definitions and enhances their inter-institutional sharing.

The BioFIND study: Characteristics of a clinically typical Parkinson's disease biomarker cohort

PubMed Central

Goldman, Jennifer G.; Alcalay, Roy N.; Xie, Tao; Tuite, Paul; Henchcliffe, Claire; Hogarth, Penelope; Amara, Amy W.; Frank, Samuel; Rudolph, Alice; Casaceli, Cynthia; Andrews, Howard; Gwinn, Katrina; Sutherland, Margaret; Kopil, Catherine; Vincent, Lona; Frasier, Mark

2016-01-01

ABSTRACT Background Identifying PD‐specific biomarkers in biofluids will greatly aid in diagnosis, monitoring progression, and therapeutic interventions. PD biomarkers have been limited by poor discriminatory power, partly driven by heterogeneity of the disease, variability of collection protocols, and focus on de novo, unmedicated patients. Thus, a platform for biomarker discovery and validation in well‐characterized, clinically typical, moderate to advanced PD cohorts is critically needed. Methods BioFIND (Fox Investigation for New Discovery of Biomarkers in Parkinson's Disease) is a cross‐sectional, multicenter biomarker study that established a repository of clinical data, blood, DNA, RNA, CSF, saliva, and urine samples from 118 moderate to advanced PD and 88 healthy control subjects. Inclusion criteria were designed to maximize diagnostic specificity by selecting participants with clinically typical PD symptoms, and clinical data and biospecimen collection utilized standardized procedures to minimize variability across sites. Results We present the study methodology and data on the cohort's clinical characteristics. Motor scores and biospecimen samples including plasma are available for practically defined off and on states and thus enable testing the effects of PD medications on biomarkers. Other biospecimens are available from off state PD assessments and from controls. Conclusion Our cohort provides a valuable resource for biomarker discovery and validation in PD. Clinical data and biospecimens, available through The Michael J. Fox Foundation for Parkinson's Research and the National Institute of Neurological Disorders and Stroke, can serve as a platform for discovering biomarkers in clinically typical PD and comparisons across PD's broad and heterogeneous spectrum. © 2016 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society PMID:27113479

42 CFR 476.85 - Conclusive effect of QIO initial denial determinations and changes as a result of DRG validations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... determinations and changes as a result of DRG validations. 476.85 Section 476.85 Public Health CENTERS FOR... changes as a result of DRG validations. A QIO initial denial determination or change as a result of DRG validation is final and binding unless, in accordance with the procedures in part 473— (a) The initial denial...

Exploring discrepancies between quantitative validation results and the geomorphic plausibility of statistical landslide susceptibility maps

NASA Astrophysics Data System (ADS)

Steger, Stefan; Brenning, Alexander; Bell, Rainer; Petschko, Helene; Glade, Thomas

2016-06-01

Empirical models are frequently applied to produce landslide susceptibility maps for large areas. Subsequent quantitative validation results are routinely used as the primary criteria to infer the validity and applicability of the final maps or to select one of several models. This study hypothesizes that such direct deductions can be misleading. The main objective was to explore discrepancies between the predictive performance of a landslide susceptibility model and the geomorphic plausibility of subsequent landslide susceptibility maps while a particular emphasis was placed on the influence of incomplete landslide inventories on modelling and validation results. The study was conducted within the Flysch Zone of Lower Austria (1,354 km2) which is known to be highly susceptible to landslides of the slide-type movement. Sixteen susceptibility models were generated by applying two statistical classifiers (logistic regression and generalized additive model) and two machine learning techniques (random forest and support vector machine) separately for two landslide inventories of differing completeness and two predictor sets. The results were validated quantitatively by estimating the area under the receiver operating characteristic curve (AUROC) with single holdout and spatial cross-validation technique. The heuristic evaluation of the geomorphic plausibility of the final results was supported by findings of an exploratory data analysis, an estimation of odds ratios and an evaluation of the spatial structure of the final maps. The results showed that maps generated by different inventories, classifiers and predictors appeared differently while holdout validation revealed similar high predictive performances. Spatial cross-validation proved useful to expose spatially varying inconsistencies of the modelling results while additionally providing evidence for slightly overfitted machine learning-based models. However, the highest predictive performances were obtained for

Establishment and Validation of GV-SAPS II Scoring System for Non-Diabetic Critically Ill Patients

PubMed Central

Liu, Wen-Yue; Lin, Shi-Gang; Zhu, Gui-Qi; Poucke, Sven Van; Braddock, Martin; Zhang, Zhongheng; Mao, Zhi; Shen, Fei-Xia

2016-01-01

Background and Aims Recently, glucose variability (GV) has been reported as an independent risk factor for mortality in non-diabetic critically ill patients. However, GV is not incorporated in any severity scoring system for critically ill patients currently. The aim of this study was to establish and validate a modified Simplified Acute Physiology Score II scoring system (SAPS II), integrated with GV parameters and named GV-SAPS II, specifically for non-diabetic critically ill patients to predict short-term and long-term mortality. Methods Training and validation cohorts were exacted from the Multiparameter Intelligent Monitoring in Intensive Care database III version 1.3 (MIMIC-III v1.3). The GV-SAPS II score was constructed by Cox proportional hazard regression analysis and compared with the original SAPS II, Sepsis-related Organ Failure Assessment Score (SOFA) and Elixhauser scoring systems using area under the curve of the receiver operator characteristic (auROC) curve. Results 4,895 and 5,048 eligible individuals were included in the training and validation cohorts, respectively. The GV-SAPS II score was established with four independent risk factors, including hyperglycemia, hypoglycemia, standard deviation of blood glucose levels (GluSD), and SAPS II score. In the validation cohort, the auROC values of the new scoring system were 0.824 (95% CI: 0.813–0.834, P< 0.001) and 0.738 (95% CI: 0.725–0.750, P< 0.001), respectively for 30 days and 9 months, which were significantly higher than other models used in our study (all P < 0.001). Moreover, Kaplan-Meier plots demonstrated significantly worse outcomes in higher GV-SAPS II score groups both for 30-day and 9-month mortality endpoints (all P< 0.001). Conclusions We established and validated a modified prognostic scoring system that integrated glucose variability for non-diabetic critically ill patients, named GV-SAPS II. It demonstrated a superior prognostic capability and may be an optimal scoring system

Clinical prediction models for young febrile infants at the emergency department: an international validation study.

PubMed

Vos-Kerkhof, Evelien de; Gomez, Borja; Milcent, Karen; Steyerberg, Ewout W; Nijman, Ruud Gerard; Smit, Frank J; Mintegi, Santiago; Moll, Henriette A; Gajdos, Vincent; Oostenbrink, Rianne

2018-05-24

To assess the diagnostic value of existing clinical prediction models (CPM; ie, statistically derived) in febrile young infants at risk for serious bacterial infections. A systematic literature review identified eight CPMs for predicting serious bacterial infections in febrile children. We validated these CPMs on four validation cohorts of febrile children in Spain (age <3 months), France (age <3 months) and two cohorts in the Netherlands (age 1-3 months and >3-12 months). We evaluated the performance of the CPMs by sensitivity/specificity, area under the receiver operating characteristic curve (AUC) and calibration studies. The original cohorts in which the prediction rules were developed (derivation cohorts) ranged from 381 to 15 781 children, with a prevalence of serious bacterial infections varying from 0.8% to 27% and spanned an age range of 0-16 years. All CPMs originally performed moderately to very well (AUC 0.60-0.93). The four validation cohorts included 159-2204 febrile children, with a median age range of 1.8 (1.2-2.4) months for the three cohorts <3 months and 8.4 (6.0-9.6) months for the cohort >3-12 months of age. The prevalence of serious bacterial infections varied between 15.1% and 17.2% in the three cohorts <3 months and was 9.8% for the cohort >3-12 months of age. Although discriminative values varied greatly, best performance was observed for four CPMs including clinical signs and symptoms, urine dipstick analyses and laboratory markers with AUC ranging from 0.68 to 0.94 in the three cohorts <3 months (ranges sensitivity: 0.48-0.94 and specificity: 0.71-0.97). For the >3-12 months' cohort AUC ranges from 0.80 to 0.89 (ranges sensitivity: 0.70-0.82 and specificity: 0.78-0.90). In general, the specificities exceeded sensitivities in our cohorts, in contrast to derivation cohorts with high sensitivities, although this effect was stronger in infants <3 months than in infants >3-12 months. We identified four CPMs, including clinical signs

Results From the VISIBILITY Iliac Study: Primary and Cohort Outcomes at 9 Months

PubMed Central

Rundback, John H.; Peeters, Patrick; George, Jon C.; Jaff, Michael R.; Faries, Peter L.

2017-01-01

Purpose: To evaluate the safety and effectiveness of primary stenting of the common (CIA) or external iliac artery (EIA) using the Visi-Pro Balloon-Expandable Peripheral Stent System for treatment of stenotic, restenotic, or occluded lesions. Methods: Between 2011 and 2012, 75 patients (mean age 64.2±8.9 years; 46 men) with Rutherford category 2–4 ischemia and atherosclerotic lesions ≤10 cm in length underwent iliac artery stenting at 17 centers in the United States and Europe. The primary outcome of the study was the major adverse event (MAE) rate at 9 months postprocedure [composite of periprocedural death, in-hospital myocardial infarction, clinically driven target lesion revascularization (CD-TLR), and amputation of the treated limb]. Secondary outcomes included 30-day MAE rate, 9-month primary patency, changes in ankle-brachial index (ABI) and the Walking Impairment Questionnaire at 30 days and 9 months postprocedure, device success, and clinically driven target vessel revascularization (CD-TVR) at 30 days and 9 months. Outcomes in specific patient cohorts (ie, gender, stent location, calcification severity, and lesion grade) were analyzed. Results: Eighty-one stents were implanted in 61 CIA and 15 EIA lesions (41 with moderate/severe calcification). The mean lesion treated length was 29.3±13.9 mm. All devices were successfully deployed. MAE occurred in 3 (4.0%) of 75 subjects at 9 months. Primary patency and freedom from CD-TVR at 9 months were both 95.8%. ABI improved from 0.67±0.14 at baseline to 0.94±0.14 and 0.96±0.16 at 30 days and 9-month follow-up, respectively (p<0.001 for both). There were no differences with respect to any of the analyzed patient characteristics, including gender. Conclusion: Nine-month results of the VISIBILITY Iliac stent study (ClinicalTrials.gov identifier NCT01402700) demonstrated safety and effectiveness for the treatment of atherosclerotic CIA and EIA lesions with the Visi-Pro stent across all treated cohorts. PMID

Validated Risk Score for Predicting 6-Month Mortality in Infective Endocarditis.

PubMed

Park, Lawrence P; Chu, Vivian H; Peterson, Gail; Skoutelis, Athanasios; Lejko-Zupa, Tatjana; Bouza, Emilio; Tattevin, Pierre; Habib, Gilbert; Tan, Ren; Gonzalez, Javier; Altclas, Javier; Edathodu, Jameela; Fortes, Claudio Querido; Siciliano, Rinaldo Focaccia; Pachirat, Orathai; Kanj, Souha; Wang, Andrew

2016-04-18

Host factors and complications have been associated with higher mortality in infective endocarditis (IE). We sought to develop and validate a model of clinical characteristics to predict 6-month mortality in IE. Using a large multinational prospective registry of definite IE (International Collaboration on Endocarditis [ICE]-Prospective Cohort Study [PCS], 2000-2006, n=4049), a model to predict 6-month survival was developed by Cox proportional hazards modeling with inverse probability weighting for surgery treatment and was internally validated by the bootstrapping method. This model was externally validated in an independent prospective registry (ICE-PLUS, 2008-2012, n=1197). The 6-month mortality was 971 of 4049 (24.0%) in the ICE-PCS cohort and 342 of 1197 (28.6%) in the ICE-PLUS cohort. Surgery during the index hospitalization was performed in 48.1% and 54.0% of the cohorts, respectively. In the derivation model, variables related to host factors (age, dialysis), IE characteristics (prosthetic or nosocomial IE, causative organism, left-sided valve vegetation), and IE complications (severe heart failure, stroke, paravalvular complication, and persistent bacteremia) were independently associated with 6-month mortality, and surgery was associated with a lower risk of mortality (Harrell's C statistic 0.715). In the validation model, these variables had similar hazard ratios (Harrell's C statistic 0.682), with a similar, independent benefit of surgery (hazard ratio 0.74, 95% CI 0.62-0.89). A simplified risk model was developed by weight adjustment of these variables. Six-month mortality after IE is ≈25% and is predicted by host factors, IE characteristics, and IE complications. Surgery during the index hospitalization is associated with lower mortality but is performed less frequently in the highest risk patients. A simplified risk model may be used to identify specific risk subgroups in IE. © 2016 The Authors. Published on behalf of the American Heart

Meal frequency patterns and glycemic properties of maternal diet in relation to preterm delivery: Results from a large prospective cohort study

PubMed Central

Birgisdottir, Bryndis Eva; Sengpiel, Verena; Brantsæter, Anne Lise; Haugen, Margareta; Myhre, Ronny; Meltzer, Helle Margrete; Jacobsson, Bo

2017-01-01

Background Dietary habits are linked to high maternal glucose levels, associated with preterm delivery. The aim of this study was to examine the associations between meal frequency and glycemic properties of maternal diet in relation to preterm delivery. Methods This prospective cohort study included 66,000 women from the Norwegian Mother and Child Cohort Study (MoBa). Meal frequency and food intake data were obtained from a validated food frequency questionnaire during mid-pregnancy. Principal component factor analysis was used with a data-driven approach, and three meal frequency patterns were identified: “snack meal”, “main meal”, and “evening meal”. Pattern scores were ranked in quartiles. Glycemic index and glycemic load were estimated from table values. Intakes of carbohydrates, added sugar, and fiber were reported in grams per day and divided into quartiles. Gestational age was obtained from the Medical Birth Registry of Norway. Preterm delivery was defined as birth at <37 gestational weeks. A Cox regression model was used to assess associations with preterm delivery. Results After adjustments, the “main meal” pattern was associated with a reduced risk of preterm delivery, with hazard ratios (HRs) of 0.89 (95% confidence interval (CI): 0.80, 0.98) and 0.90 (95% CI: 0.81, 0.99) for the third and fourth quartiles, respectively, and p for trend of 0.028. This was mainly attributed to the group of women with BMI ≥25 kg/m2, with HRs of 0.87 (95% CI: 0.79, 0.96) and 0.89 (95% CI: 0.80, 0.98) for the third and fourth quartiles, respectively, and p for trend of 0.010. There was no association between glycemic index, glycemic load, carbohydrates, added sugar, fiber, or the remaining meal frequency patterns and preterm delivery. Conclusion Regular consumption of main meals (breakfast, lunch, dinner) was associated with a lower risk of preterm delivery. Diet should be further studied as potential contributing factors for preterm delivery. PMID

A Randomized Controlled Trial of Short and Standard-Length Consent Forms for a Genetic Cohort Study: Is Longer Better?

PubMed Central

Matsui, Kenji; Lie, Reidar K.; Turin, Tanvir C.; Kita, Yoshikuni

2012-01-01

Background Although the amount of detail in informed consent documents has increased over time and the documents have therefore become very long, there is little research on whether longer informed consent documents actually result in (1) better informed research subjects or (2) higher consent rates. We therefore conducted an add-on randomized controlled trial to the Takashima Study, a prospective Japanese population-based genetic cohort study, to test the hypothesis that a shorter informed consent form would satisfy both of the above goals. Methods Standard (10 459 words, 11 pages) and short (3602 words, 5 pages) consent forms in Japanese were developed and distributed using cluster-randomization to 293 potential cohort subjects living in 9 medico-social units and 288 subjects in 8 medico-social units, respectively. Results Few differences were found between the 2 groups with regard to outcome measures, including participants’ self-perceived understanding, recall of information, concerns, voluntariness, trust, satisfaction, sense of duty, and consent rates. Conclusions A short informed consent form was no less valid than a standard form with regard to fulfilling ethical requirements and securing the scientific validity of research. PMID:22447213

Proposal and validation of a new model to estimate survival for hepatocellular carcinoma patients.

PubMed

Liu, Po-Hong; Hsu, Chia-Yang; Hsia, Cheng-Yuan; Lee, Yun-Hsuan; Huang, Yi-Hsiang; Su, Chien-Wei; Lee, Fa-Yauh; Lin, Han-Chieh; Huo, Teh-Ia

2016-08-01

The survival of hepatocellular carcinoma (HCC) patients is heterogeneous. We aim to develop and validate a simple prognostic model to estimate survival for HCC patients (MESH score). A total of 3182 patients were randomised into derivation and validation cohort. Multivariate analysis was used to identify independent predictors of survival in the derivation cohort. The validation cohort was employed to examine the prognostic capabilities. The MESH score allocated 1 point for each of the following parameters: large tumour (beyond Milan criteria), presence of vascular invasion or metastasis, Child-Turcotte-Pugh score ≥6, performance status ≥2, serum alpha-fetoprotein level ≥20 ng/ml, and serum alkaline phosphatase ≥200 IU/L, with a maximal of 6 points. In the validation cohort, significant survival differences were found across all MESH scores from 0 to 6 (all p < 0.01). The MESH system was associated with the highest homogeneity and lowest corrected Akaike information criterion compared with Barcelona Clínic Liver Cancer, Hong Kong Liver Cancer (HKLC), Cancer of the Liver Italian Program, Taipei Integrated Scoring and model to estimate survival in ambulatory HCC Patients systems. The prognostic accuracy of the MESH scores remained constant in patients with hepatitis B- or hepatitis C-related HCC. The MESH score can also discriminate survival for patients from early to advanced stages of HCC. This newly proposed simple and accurate survival model provides enhanced prognostic accuracy for HCC. The MESH system is a useful supplement to the BCLC and HKLC classification schemes in refining treatment strategies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Empirically Derived Dehydration Scoring and Decision Tree Models for Children With Diarrhea: Assessment and Internal Validation in a Prospective Cohort Study in Dhaka, Bangladesh

PubMed Central

Glavis-Bloom, Justin; Modi, Payal; Nasrin, Sabiha; Rege, Soham; Chu, Chieh; Schmid, Christopher H; Alam, Nur H

2015-01-01

Introduction: Diarrhea remains one of the most common and most deadly conditions affecting children worldwide. Accurately assessing dehydration status is critical to determining treatment course, yet no clinical diagnostic models for dehydration have been empirically derived and validated for use in resource-limited settings. Methods: In the Dehydration: Assessing Kids Accurately (DHAKA) prospective cohort study, a random sample of children under 5 with acute diarrhea was enrolled between February and June 2014 in Bangladesh. Local nurses assessed children for clinical signs of dehydration on arrival, and then serial weights were obtained as subjects were rehydrated. For each child, the percent weight change with rehydration was used to classify subjects with severe dehydration (>9% weight change), some dehydration (3–9%), or no dehydration (<3%). Clinical variables were then entered into logistic regression and recursive partitioning models to develop the DHAKA Dehydration Score and DHAKA Dehydration Tree, respectively. Models were assessed for their accuracy using the area under their receiver operating characteristic curve (AUC) and for their reliability through repeat clinical exams. Bootstrapping was used to internally validate the models. Results: A total of 850 children were enrolled, with 771 included in the final analysis. Of the 771 children included in the analysis, 11% were classified with severe dehydration, 45% with some dehydration, and 44% with no dehydration. Both the DHAKA Dehydration Score and DHAKA Dehydration Tree had significant AUCs of 0.79 (95% CI = 0.74, 0.84) and 0.76 (95% CI = 0.71, 0.80), respectively, for the diagnosis of severe dehydration. Additionally, the DHAKA Dehydration Score and DHAKA Dehydration Tree had significant positive likelihood ratios of 2.0 (95% CI = 1.8, 2.3) and 2.5 (95% CI = 2.1, 2.8), respectively, and significant negative likelihood ratios of 0.23 (95% CI = 0.13, 0.40) and 0.28 (95% CI�

Prediction of prostate cancer in unscreened men: external validation of a risk calculator.

PubMed

van Vugt, Heidi A; Roobol, Monique J; Kranse, Ries; Määttänen, Liisa; Finne, Patrik; Hugosson, Jonas; Bangma, Chris H; Schröder, Fritz H; Steyerberg, Ewout W

2011-04-01

Prediction models need external validation to assess their value beyond the setting where the model was derived from. To assess the external validity of the European Randomized study of Screening for Prostate Cancer (ERSPC) risk calculator (www.prostatecancer-riskcalculator.com) for the probability of having a positive prostate biopsy (P(posb)). The ERSPC risk calculator was based on data of the initial screening round of the ERSPC section Rotterdam and validated in 1825 and 531 men biopsied at the initial screening round in the Finnish and Swedish sections of the ERSPC respectively. P(posb) was calculated using serum prostate specific antigen (PSA), outcome of digital rectal examination (DRE), transrectal ultrasound and ultrasound assessed prostate volume. The external validity was assessed for the presence of cancer at biopsy by calibration (agreement between observed and predicted outcomes), discrimination (separation of those with and without cancer), and decision curves (for clinical usefulness). Prostate cancer was detected in 469 men (26%) of the Finnish cohort and in 124 men (23%) of the Swedish cohort. Systematic miscalibration was present in both cohorts (mean predicted probability 34% versus 26% observed, and 29% versus 23% observed, both p<0.001). The areas under the curves were 0.76 and 0.78, and substantially lower for the model with PSA only (0.64 and 0.68 respectively). The model proved clinically useful for any decision threshold compared with a model with PSA only, PSA and DRE, or biopsying all men. A limitation is that the model is based on sextant biopsies results. The ERSPC risk calculator discriminated well between those with and without prostate cancer among initially screened men, but overestimated the risk of a positive biopsy. Further research is necessary to assess the performance and applicability of the ERSPC risk calculator when a clinical setting is considered rather than a screening setting. Copyright © 2010 Elsevier Ltd. All rights

Disk displacement, eccentric condylar position, osteoarthrosis - misnomers for variations of normality? Results and interpretations from an MRI study in two age cohorts.

PubMed

Türp, Jens C; Schlenker, Anna; Schröder, Johannes; Essig, Marco; Schmitter, Marc

2016-11-17

Clinical decision-making and prognostic statements in individuals with manifest or suspected temporomandibular disorders (TMDs) may involve assessment of (a) the position of articular disc relative to the mandibular condyle, (b) the location of the condyle relative to the temporal joint surfaces, and (c) the depth of the glenoid fossa of the temporomandibular joints (TMJs). The aim of this study was twofold: (1) Determination of the prevalence of these variables in two representative population-based birth cohorts. (2) Reinterpretation of the clinical significance of the findings. From existing magnetic resonance imaging (MRI) scans of the TMJs that had been taken in 2005 and 2006 from 72 subjects born between 1930 and 1932 and between 1950 and 1952, respectively, the condylar position at closed jaw was calculated as percentage displacement of the condyle from absolute centricity. By using the criteria introduced by Orsini et al. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 86:489-97, 1998), a textbook-like disc position at closed jaw was distinguished from an anterior location. TMJ morphology of the temporal joint surfaces was assessed at open jaw by measuring the depth of the glenoid fossa, using the method proposed by Muto et al. (J Oral Maxillofac Surg 52:1269-72, 1994). Frequency distributions were recorded for the condylar and disc positions at closed jaw. Student's t-test with independent samples was used as test of significance to detect differences of condylar positions between the age cohorts (1930 vs. 1950) and the sexes. The significance levels were set at 5%. First, the results from the measurement of the age cohorts were compared without differentiation of sexes, i.e., age cohort 1930-1932 versus age cohort 1950-1952. Subsequently, the age cohorts were compared by sex, i.e., men in cohort 1930-1932 versus men in cohort 1950-1952, and women in cohort 1930-1932 women men in cohort 1950-1952. In both cohorts, condylar position was characterized by

Development of quantitative exposure data for a pooled exposure-response analysis of 10 silica cohorts.

PubMed

Mannetje, Andrea 't; Steenland, Kyle; Checkoway, Harvey; Koskela, Riitta-Sisko; Koponen, Matti; Attfield, Michael; Chen, Jingqiong; Hnizdo, Eva; DeKlerk, Nicholas; Dosemeci, Mustafa

2002-08-01

Comprehensive quantitative silica exposure estimates over time, measured in the same units across a number of cohorts, would make possible a pooled exposure-response analysis for lung cancer. Such an analysis would help clarify the continuing controversy regarding whether silica causes lung cancer. Existing quantitative exposure data for 10 silica-exposed cohorts were retrieved from the original investigators. Occupation- and time-specific exposure estimates were either adopted/adapted or developed for each cohort, and converted to milligram per cubic meter (mg/m(3)) respirable crystalline silica. Quantitative exposure assignments were typically based on a large number (thousands) of raw measurements, or otherwise consisted of exposure estimates by experts (for two cohorts). Median exposure level of the cohorts ranged between 0.04 and 0.59 mg/m(3) respirable crystalline silica. Exposure estimates were partially validated via their successful prediction of silicosis in these cohorts. Existing data were successfully adopted or modified to create comparable quantitative exposure estimates over time for 10 silica-exposed cohorts, permitting a pooled exposure-response analysis. The difficulties encountered in deriving common exposure estimates across cohorts are discussed. Copyright 2002 Wiley-Liss, Inc.

Challenges in validating model results for first year ice

NASA Astrophysics Data System (ADS)

Melsom, Arne; Eastwood, Steinar; Xie, Jiping; Aaboe, Signe; Bertino, Laurent

2017-04-01

In order to assess the quality of model results for the distribution of first year ice, a comparison with a product based on observations from satellite-borne instruments has been performed. Such a comparison is not straightforward due to the contrasting algorithms that are used in the model product and the remote sensing product. The implementation of the validation is discussed in light of the differences between this set of products, and validation results are presented. The model product is the daily updated 10-day forecast from the Arctic Monitoring and Forecasting Centre in CMEMS. The forecasts are produced with the assimilative ocean prediction system TOPAZ. Presently, observations of sea ice concentration and sea ice drift are introduced in the assimilation step, but data for sea ice thickness and ice age (or roughness) are not included. The model computes the age of the ice by recording and updating the time passed after ice formation as sea ice grows and deteriorates as it is advected inside the model domain. Ice that is younger than 365 days is classified as first year ice. The fraction of first-year ice is recorded as a tracer in each grid cell. The Ocean and Sea Ice Thematic Assembly Centre in CMEMS redistributes a daily product from the EUMETSAT OSI SAF of gridded sea ice conditions which include "ice type", a representation of the separation of regions between those infested by first year ice, and those infested by multi-year ice. The ice type is parameterized based on data for the gradient ratio GR(19,37) from SSMIS observations, and from the ASCAT backscatter parameter. This product also includes information on ambiguity in the processing of the remote sensing data, and the product's confidence level, which have a strong seasonal dependency.

Validation and Adjustment of the Leipzig-Halifax Acute Aortic Dissection Type A Scorecard.

PubMed

Mejàre-Berggren, Hanna; Olsson, Christian

2017-11-01

The novel Leipzig-Halifax (LH) scorecard for acute aortic dissection type A (AADA) stratifies risk of in-hospital death based on age, malperfusion syndromes, critical preoperative state, and coronary disease. The study aim was to externally validate the LH scorecard performance and, if adequate, propose adjustments. All consecutive AADA patients operated on from 1996 to 2016 (n = 509) were included to generate an external validation cohort. Variables related to in-hospital death were analyzed using univariable and multivariable analysis. The LH scorecard was applied to the validation cohort, compared with the original study, and variable selection was adjusted using validation measures for discrimination and calibration. In-hospital mortality rate was 17.7% (LH cohort 18.7%). Critical preoperative state and Penn class non-Aa were independent predictors (odds ratio [OR] 2.42 and 2.45, respectively) of in-hospital death. The LH scorecard was adjusted to include Penn class non-Aa, critical preoperative state, and coronary disease. Assessing discrimination, area under receiver operator characteristic curve for the LH scorecard was 0.61 versus 0.66 for the new scorecard (p = 0.086). In-hospital mortality rates in low-, medium-, and high-risk groups were 14%, 15%, and 48%, respectively (LH scorecard) versus 11%, 23%, and 43%, respectively (new scorecard), and goodness-of-fit p value was 0.01 versus 0.86, indicating better calibration by the new scorecard. A lower Akaike information criterion value, 464 versus 448, favored the new scorecard. Through adjustment of the LH scorecard after external validation, prognostic performance improved. Further validated, the LH scorecard could be a valuable risk prediction tool. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

42 CFR 476.94 - Notice of QIO initial denial determination and changes as a result of a DRG validation.

Code of Federal Regulations, 2013 CFR

2013-10-01

... changes as a result of a DRG validation. 476.94 Section 476.94 Public Health CENTERS FOR MEDICARE... changes as a result of a DRG validation. (a) Notice of initial denial determination—(1) Parties to be... working days of identification; (vi) For retrospective review, (excluding DRG validation and post...

Lung Cancer Risk from Plutonium: A Pooled Analysis of the Mayak and Sellafield Worker Cohorts.

PubMed

Gillies, Michael; Kuznetsova, Irina; Sokolnikov, Mikhail; Haylock, Richard; O'Hagan, Jackie; Tsareva, Yulia; Labutina, Elena

2017-12-01

In this study, lung cancer risk from occupational plutonium exposure was analyzed in a pooled cohort of Mayak and Sellafield workers, two of the most informative cohorts in the world with detailed plutonium urine monitoring programs. The pooled cohort comprised 45,817 workers: 23,443 Sellafield workers first employed during 1947-2002 with follow-up until the end of 2005 and 22,374 Mayak workers first employed during 1948-1982 with follow-up until the end of 2008. In the pooled cohort 1,195 lung cancer deaths were observed (789 Mayak, 406 Sellafield) but only 893 lung cancer incidences (509 Mayak, 384 Sellafield, due to truncated follow-up in the incidence analysis). Analyses were performed using Poisson regression models, and were based on doses derived from individual radiation monitoring data using an updated dose assessment methodology developed in the study. There was clear evidence of a linear association between cumulative internal plutonium lung dose and risk of both lung cancer mortality and incidence in the pooled cohort. The pooled point estimates of the excess relative risk (ERR) from plutonium exposure for both lung cancer mortality and incidence were within the range of 5-8 per Gy for males at age 60. The ERR estimates in relationship to external gamma radiation were also significantly raised and in the range 0.2-0.4 per Gy of cumulative gamma dose to the lung. The point estimates of risk, for both external and plutonium exposure, were comparable between the cohorts, which suggests that the pooling of these data was valid. The results support point estimates of relative biological effectiveness (RBE) in the range of 10-25, which is in broad agreement with the value of 20 currently adopted in radiological protection as the radiation weighting factor for alpha particles, however, the uncertainty on this value (RBE = 21; 95% CI: 9-178) is large. The results provide direct evidence that the plutonium risks in each cohort are of the same order of magnitude

Simulated Driving Assessment (SDA) for Teen Drivers: Results from a Validation Study

PubMed Central

McDonald, Catherine C.; Kandadai, Venk; Loeb, Helen; Seacrist, Thomas S.; Lee, Yi-Ching; Winston, Zachary; Winston, Flaura K.

2015-01-01

Background Driver error and inadequate skill are common critical reasons for novice teen driver crashes, yet few validated, standardized assessments of teen driving skills exist. The purpose of this study was to evaluate the construct and criterion validity of a newly developed Simulated Driving Assessment (SDA) for novice teen drivers. Methods The SDA's 35-minute simulated drive incorporates 22 variations of the most common teen driver crash configurations. Driving performance was compared for 21 inexperienced teens (age 16–17 years, provisional license ≤90 days) and 17 experienced adults (age 25–50 years, license ≥5 years, drove ≥100 miles per week, no collisions or moving violations ≤3 years). SDA driving performance (Error Score) was based on driving safety measures derived from simulator and eye-tracking data. Negative driving outcomes included simulated collisions or run-off-the-road incidents. A professional driving evaluator/instructor reviewed videos of SDA performance (DEI Score). Results The SDA demonstrated construct validity: 1.) Teens had a higher Error Score than adults (30 vs. 13, p=0.02); 2.) For each additional error committed, the relative risk of a participant's propensity for a simulated negative driving outcome increased by 8% (95% CI: 1.05–1.10, p<0.01). The SDA demonstrated criterion validity: Error Score was correlated with DEI Score (r=−0.66, p<0.001). Conclusions This study supports the concept of validated simulated driving tests like the SDA to assess novice driver skill in complex and hazardous driving scenarios. The SDA, as a standard protocol to evaluate teen driver performance, has the potential to facilitate screening and assessment of teen driving readiness and could be used to guide targeted skill training. PMID:25740939

Morbidity and mortality of complex spine surgery: a prospective cohort study in 679 patients validating the Spine AdVerse Event Severity (SAVES) system in a European population.

PubMed

Karstensen, Sven; Bari, Tanvir; Gehrchen, Martin; Street, John; Dahl, Benny

2016-02-01

Most literature on complications in spine surgery has been retrospective or based on national databases with few variables. The Spine AdVerse Events Severity (SAVES) system has been found reliable and valid in two Canadian centers, providing precise information regarding all adverse events (AEs). This study aimed to determine the mortality and examine the incidence of morbidity in patients undergoing complex spinal surgery, including pediatric patients, and to validate the SAVES system in a European population. A prospective, consecutive cohort study was conducted using the SAVES version 2010 in the period from January 1, 2013 until December 31, 2013. A retrospective analysis was performed on all patients operated from November 1, 2011 until October 31, 2012 for comparison. Patients undergoing spinal surgery at a tertiary referral center comprised the patient sample. Morbidity and mortality were determined according to the newest version of the SAVES system and compared with the Canadian cohort. Other outcomes were length of stay, readmission, unplanned second surgery during index admission, as well as wound infections requiring revision. All patients undergoing spinal surgery at an academic tertiary referral center in the study period were prospectively included. The newest version of SAVES system was used, and a research coordinator collected all intraoperative and perioperative data prospectively. Once a week all patients were reviewed for additional events, validation of the data, and clarification of any questions. Patients were grouped according to the type of admission (elective of emergency) and age, and subgrouped according to a major diagnostic group. The survival status was registered on January 31, 2014 to obtain 30-day survival. A total of 679 consecutive cases were included with 100% data completion. The in-hospital mortality was 1.3% and the 30-day mortality was 2.7%; all occurring after emergency procedures. The number of intraoperative AEs was 162

Complete Statistical Survey Results of 1982 Texas Competency Validation Project.

ERIC Educational Resources Information Center

Rogers, Sandra K.; Dahlberg, Maurine F.

This report documents a project to develop current statewide validated competencies for auto mechanics, diesel mechanics, welding, office occupations, and printing. Section 1 describes the four steps used in the current competency validation project and provides a standardized process for conducting future studies at the local or statewide level.…

Validation of questionnaire-reported hearing with medical records: A report from the Swiss Childhood Cancer Survivor Study

PubMed Central

Scheinemann, Katrin; Grotzer, Michael; Kompis, Martin; Kuehni, Claudia E.

2017-01-01

Background Hearing loss is a potential late effect after childhood cancer. Questionnaires are often used to assess hearing in large cohorts of childhood cancer survivors and it is important to know if they can provide valid measures of hearing loss. We therefore assessed agreement and validity of questionnaire-reported hearing in childhood cancer survivors using medical records as reference. Procedure In this validation study, we studied 361 survivors of childhood cancer from the Swiss Childhood Cancer Survivor Study (SCCSS) who had been diagnosed after 1989 and had been exposed to ototoxic cancer treatment. Questionnaire-reported hearing was compared to the information in medical records. Hearing loss was defined as ≥ grade 1 according to the SIOP Boston Ototoxicity Scale. We assessed agreement and validity of questionnaire-reported hearing overall and stratified by questionnaire respondents (survivor or parent), sociodemographic characteristics, time between follow-up and questionnaire and severity of hearing loss. Results Questionnaire reports agreed with medical records in 85% of respondents (kappa 0.62), normal hearing was correctly assessed in 92% of those with normal hearing (n = 249), and hearing loss was correctly assessed in 69% of those with hearing loss (n = 112). Sensitivity of the questionnaires was 92%, 74%, and 39% for assessment of severe, moderate and mild bilateral hearing loss; and 50%, 33% and 10% for severe, moderate and mild unilateral hearing loss, respectively. Results did not differ by sociodemographic characteristics of the respondents, and survivor- and parent-reports were equally valid. Conclusions Questionnaires are a useful tool to assess hearing in large cohorts of childhood cancer survivors, but underestimate mild and unilateral hearing loss. Further research should investigate whether the addition of questions with higher sensitivity for mild degrees of hearing loss could improve the results. PMID:28333999

Retrospective cohort mortality study of workers at an aircraft maintenance facility. I. Epidemiological results.

PubMed Central

Spirtas, R; Stewart, P A; Lee, J S; Marano, D E; Forbes, C D; Grauman, D J; Pettigrew, H M; Blair, A; Hoover, R N; Cohen, J L

1991-01-01

. Hypothesis generating results are presented by a variety of exposures for causes of death not showing excesses in the overall cohort. PMID:1878308

The development and validation of a scoring tool to predict the operative duration of elective laparoscopic cholecystectomy.

PubMed

Bharamgoudar, Reshma; Sonsale, Aniket; Hodson, James; Griffiths, Ewen

2018-07-01

The ability to accurately predict operative duration has the potential to optimise theatre efficiency and utilisation, thus reducing costs and increasing staff and patient satisfaction. With laparoscopic cholecystectomy being one of the most commonly performed procedures worldwide, a tool to predict operative duration could be extremely beneficial to healthcare organisations. Data collected from the CholeS study on patients undergoing cholecystectomy in UK and Irish hospitals between 04/2014 and 05/2014 were used to study operative duration. A multivariable binary logistic regression model was produced in order to identify significant independent predictors of long (> 90 min) operations. The resulting model was converted to a risk score, which was subsequently validated on second cohort of patients using ROC curves. After exclusions, data were available for 7227 patients in the derivation (CholeS) cohort. The median operative duration was 60 min (interquartile range 45-85), with 17.7% of operations lasting longer than 90 min. Ten factors were found to be significant independent predictors of operative durations > 90 min, including ASA, age, previous surgical admissions, BMI, gallbladder wall thickness and CBD diameter. A risk score was then produced from these factors, and applied to a cohort of 2405 patients from a tertiary centre for external validation. This returned an area under the ROC curve of 0.708 (SE = 0.013, p < 0.001), with the proportions of operations lasting > 90 min increasing more than eightfold from 5.1 to 41.8% in the extremes of the score. The scoring tool produced in this study was found to be significantly predictive of long operative durations on validation in an external cohort. As such, the tool may have the potential to enable organisations to better organise theatre lists and deliver greater efficiencies in care.

Development and Validation of a Risk Score for Chronic Kidney Disease in HIV Infection Using Prospective Cohort Data from the D:A:D Study

PubMed Central

Mocroft, Amanda; Lundgren, Jens D.; Ross, Michael; Law, Matthew; Reiss, Peter; Kirk, Ole; Smith, Colette; Wentworth, Deborah; Neuhaus, Jacqueline; Fux, Christoph A.; Moranne, Olivier; Morlat, Phillipe; Johnson, Margaret A.; Ryom, Lene

2015-01-01

Background Chronic kidney disease (CKD) is a major health issue for HIV-positive individuals, associated with increased morbidity and mortality. Development and implementation of a risk score model for CKD would allow comparison of the risks and benefits of adding potentially nephrotoxic antiretrovirals to a treatment regimen and would identify those at greatest risk of CKD. The aims of this study were to develop a simple, externally validated, and widely applicable long-term risk score model for CKD in HIV-positive individuals that can guide decision making in clinical practice. Methods and Findings A total of 17,954 HIV-positive individuals from the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study with ≥3 estimated glomerular filtration rate (eGFR) values after 1 January 2004 were included. Baseline was defined as the first eGFR > 60 ml/min/1.73 m2 after 1 January 2004; individuals with exposure to tenofovir, atazanavir, atazanavir/ritonavir, lopinavir/ritonavir, other boosted protease inhibitors before baseline were excluded. CKD was defined as confirmed (>3 mo apart) eGFR ≤ 60 ml/min/1.73 m2. Poisson regression was used to develop a risk score, externally validated on two independent cohorts. In the D:A:D study, 641 individuals developed CKD during 103,185 person-years of follow-up (PYFU; incidence 6.2/1,000 PYFU, 95% CI 5.7–6.7; median follow-up 6.1 y, range 0.3–9.1 y). Older age, intravenous drug use, hepatitis C coinfection, lower baseline eGFR, female gender, lower CD4 count nadir, hypertension, diabetes, and cardiovascular disease (CVD) predicted CKD. The adjusted incidence rate ratios of these nine categorical variables were scaled and summed to create the risk score. The median risk score at baseline was −2 (interquartile range –4 to 2). There was a 1:393 chance of developing CKD in the next 5 y in the low risk group (risk score < 0, 33 events), rising to 1:47 and 1:6 in the medium (risk score 0–4, 103 events) and high risk

Determinants of Acute Kidney Injury Duration After Cardiac Surgery: An Externally Validated Tool

PubMed Central

Brown, Jeremiah R.; Kramer, Robert S.; MacKenzie, Todd A.; Coca, Steven G.; Sint, Kyaw; Parikh, Chirag R.

2013-01-01

Background Acute kidney injury (AKI) duration following cardiac surgery is associated with poor survival in a dose-dependent manner. However, it is not known what peri-operative risk factors contribute to prolonged AKI and delayed recovery. We sought to identify peri-operative risk factors that predict duration of AKI, a complication that effects short and long term survival. Methods We studied 4,987 consecutive cardiac surgery patients from 2002 through 2007. AKI was defined as a ≥0.3 (mg/dL) or ≥50% increase in SCr from baseline. Duration of AKI was defined by the number of days AKI was present. Step-wise multivariable negative binomial regression analysis was conducted using peri-operative risk factors for AKI duration. C-index was estimated by Kendall’s tau. Results AKI developed in 39% of patients with a median duration of AKI at 3 days and ranged from 1 to 108 days. Patients without AKI had duration of zero days. Independent predictors of AKI duration included baseline patient and disease characteristics, operative and post-operative factors. Prediction for mean duration of AKI was developed using coefficients from the regression model and externally validated the model on 1,219 cardiac surgery patients in a separate cardiac surgery cohort (TRIBE-AKI). The C-index was 0.65 (p<0.001) for the derivation cohort and 0.62 (p<0.001) for the validation cohort. Conclusion We identified and externally validated peri-operative predictors of AKI duration. These risk-factors will be useful to evaluate a patient’s risk for the tempo of recovery from AKI after cardiac surgery and subsequent short and long term survival. The level of awareness created by working with these risk factors have implications regarding positive changes in processes of care that have the potential to decrease the incidence and mitigate AKI. PMID:22206952

Discovery and validation of cell cycle arrest biomarkers in human acute kidney injury

PubMed Central

2013-01-01

Introduction Acute kidney injury (AKI) can evolve quickly and clinical measures of function often fail to detect AKI at a time when interventions are likely to provide benefit. Identifying early markers of kidney damage has been difficult due to the complex nature of human AKI, in which multiple etiologies exist. The objective of this study was to identify and validate novel biomarkers of AKI. Methods We performed two multicenter observational studies in critically ill patients at risk for AKI - discovery and validation. The top two markers from discovery were validated in a second study (Sapphire) and compared to a number of previously described biomarkers. In the discovery phase, we enrolled 522 adults in three distinct cohorts including patients with sepsis, shock, major surgery, and trauma and examined over 300 markers. In the Sapphire validation study, we enrolled 744 adult subjects with critical illness and without evidence of AKI at enrollment; the final analysis cohort was a heterogeneous sample of 728 critically ill patients. The primary endpoint was moderate to severe AKI (KDIGO stage 2 to 3) within 12 hours of sample collection. Results Moderate to severe AKI occurred in 14% of Sapphire subjects. The two top biomarkers from discovery were validated. Urine insulin-like growth factor-binding protein 7 (IGFBP7) and tissue inhibitor of metalloproteinases-2 (TIMP-2), both inducers of G1 cell cycle arrest, a key mechanism implicated in AKI, together demonstrated an AUC of 0.80 (0.76 and 0.79 alone). Urine [TIMP-2]·[IGFBP7] was significantly superior to all previously described markers of AKI (P <0.002), none of which achieved an AUC >0.72. Furthermore, [TIMP-2]·[IGFBP7] significantly improved risk stratification when added to a nine-variable clinical model when analyzed using Cox proportional hazards model, generalized estimating equation, integrated discrimination improvement or net reclassification improvement. Finally, in sensitivity analyses [TIMP-2]�

42 CFR 476.94 - Notice of QIO initial denial determination and changes as a result of a DRG validation.

Code of Federal Regulations, 2012 CFR

2012-10-01

... changes as a result of a DRG validation. 476.94 Section 476.94 Public Health CENTERS FOR MEDICARE... changes as a result of a DRG validation. (a) Notice of initial denial determination—(1) Parties to be... retrospective review, (excluding DRG validation and post procedure review), within 3 working days of the initial...

42 CFR 476.94 - Notice of QIO initial denial determination and changes as a result of a DRG validation.

Code of Federal Regulations, 2011 CFR

2011-10-01

... changes as a result of a DRG validation. 476.94 Section 476.94 Public Health CENTERS FOR MEDICARE... changes as a result of a DRG validation. (a) Notice of initial denial determination—(1) Parties to be... retrospective review, (excluding DRG validation and post procedure review), within 3 working days of the initial...

How Computer Literacy and Socioeconomic Status Affect Attitudes Toward a Web-Based Cohort: Results From the NutriNet-Santé Study

PubMed Central

Méjean, Caroline; Andreeva, Valentina A; Kesse-Guyot, Emmanuelle; Fassier, Philippine; Galan, Pilar; Hercberg, Serge; Touvier, Mathilde

2015-01-01

Background In spite of the growing literature in the field of e-epidemiology, clear evidence about computer literacy or attitudes toward respondent burden among e-cohort participants is largely lacking. Objective We assessed the computer and Internet skills of participants in the NutriNet-Santé Web-based cohort. We then explored attitudes toward the study demands/respondent burden according to levels of computer literacy and sociodemographic status. Methods Self-reported data from 43,028 e-cohort participants were collected in 2013 via a Web-based questionnaire. We employed unconditional logistic and linear regression analyses. Results Approximately one-quarter of participants (23.79%, 10,235/43,028) reported being inexperienced in terms of computer use. Regarding attitudes toward participant burden, women tended to be more favorable (eg, “The overall website use is easy”) than were men (OR 0.65, 95% CI 0.59-0.71, P<.001), whereas better educated participants (>12 years of schooling) were less likely to accept the demands associated with participation (eg, “I receive questionnaires too often”) compared to their less educated counterparts (OR 1.62, 95% CI 1.48-1.76, P<.001). Conclusions A substantial proportion of participants had low computer/Internet skills, suggesting that this does not represent a barrier to participation in Web-based cohorts. Our study also suggests that several subgroups of participants with lower computer skills (eg, women or those with lower educational level) might more readily accept the demands associated with participation in the Web cohort. These findings can help guide future Web-based research strategies. PMID:25648178

A Chinese Birth Cohort: Theoretical Implications

ERIC Educational Resources Information Center

Friday, Paul C.; Ren, Xin; Weitekamp, Elmar; Kerner, Hans-Jurgen; Taylor, Terrance

2005-01-01

Research on delinquency has shown consistent results across Western industrialized countries. Few studies have been done in non-Western cultures. This study reports on the results of a birth cohort study in China, which was started by Marvin Wolfgang but never completed. The cohort, born in 1973, was traced through official and community files.…

The health system impact of false positive newborn screening results for medium-chain acyl-CoA dehydrogenase deficiency: a cohort study.

PubMed

Karaceper, Maria D; Chakraborty, Pranesh; Coyle, Doug; Wilson, Kumanan; Kronick, Jonathan B; Hawken, Steven; Davies, Christine; Brownell, Marni; Dodds, Linda; Feigenbaum, Annette; Fell, Deshayne B; Grosse, Scott D; Guttmann, Astrid; Laberge, Anne-Marie; Mhanni, Aizeddin; Miller, Fiona A; Mitchell, John J; Nakhla, Meranda; Prasad, Chitra; Rockman-Greenberg, Cheryl; Sparkes, Rebecca; Wilson, Brenda J; Potter, Beth K

2016-02-03

There is no consensus in the literature regarding the impact of false positive newborn screening results on early health care utilization patterns. We evaluated the impact of false positive newborn screening results for medium-chain acyl-CoA dehydrogenase deficiency (MCADD) in a cohort of Ontario infants. The cohort included all children who received newborn screening in Ontario between April 1, 2006 and March 31, 2010. Newborn screening and diagnostic confirmation results were linked to province-wide health care administrative datasets covering physician visits, emergency department visits, and inpatient hospitalizations, to determine health service utilization from April 1, 2006 through March 31, 2012. Incidence rate ratios (IRRs) were used to compare those with false positive results for MCADD to those with negative newborn screening results, stratified by age at service use. We identified 43 infants with a false positive newborn screening result for MCADD during the study period. These infants experienced significantly higher rates of physician visits (IRR: 1.42) and hospitalizations (IRR: 2.32) in the first year of life relative to a screen negative cohort in adjusted analyses. Differences in health services use were not observed after the first year of life. The higher use of some health services among false positive infants during the first year of life may be explained by a psychosocial impact of false positive results on parental perceptions of infant health, and/or by differences in underlying health status. Understanding the impact of false positive newborn screening results can help to inform newborn screening programs in designing support and education for families. This is particularly important as additional disorders are added to expanded screening panels, yielding important clinical benefits for affected children but also a higher frequency of false positive findings.

Testing multiple statistical hypotheses resulted in spurious associations: a study of astrological signs and health.

PubMed

Austin, Peter C; Mamdani, Muhammad M; Juurlink, David N; Hux, Janet E

2006-09-01

To illustrate how multiple hypotheses testing can produce associations with no clinical plausibility. We conducted a study of all 10,674,945 residents of Ontario aged between 18 and 100 years in 2000. Residents were randomly assigned to equally sized derivation and validation cohorts and classified according to their astrological sign. Using the derivation cohort, we searched through 223 of the most common diagnoses for hospitalization until we identified two for which subjects born under one astrological sign had a significantly higher probability of hospitalization compared to subjects born under the remaining signs combined (P<0.05). We tested these 24 associations in the independent validation cohort. Residents born under Leo had a higher probability of gastrointestinal hemorrhage (P=0.0447), while Sagittarians had a higher probability of humerus fracture (P=0.0123) compared to all other signs combined. After adjusting the significance level to account for multiple comparisons, none of the identified associations remained significant in either the derivation or validation cohort. Our analyses illustrate how the testing of multiple, non-prespecified hypotheses increases the likelihood of detecting implausible associations. Our findings have important implications for the analysis and interpretation of clinical studies.

Development and validation of a clinical risk score for predicting drug-resistant bacterial pneumonia in older Chinese patients.

PubMed

Ma, Hon Ming; Ip, Margaret; Woo, Jean; Hui, David S C

2014-05-01

Health care-associated pneumonia (HCAP) and drug-resistant bacterial pneumonia may not share identical risk factors. We have shown that bronchiectasis, recent hospitalization and severe pneumonia (confusion, blood urea level, respiratory rate, low blood pressure and 65 year old (CURB-65) score ≥ 3) were independent predictors of pneumonia caused by potentially drug-resistant (PDR) pathogens. This study aimed to develop and validate a clinical risk score for predicting drug-resistant bacterial pneumonia in older patients. We derived a risk score by assigning a weighting to each of these risk factors as follows: 14, bronchiectasis; 5, recent hospitalization; 2, severe pneumonia. A 0.5 point was defined for the presence of other risk factors for HCAP. We compared the areas under the receiver-operating characteristics curve (AUROC) of our risk score and the HCAP definition in predicting PDR pathogens in two cohorts of older patients hospitalized with non-nosocomial pneumonia. The derivation and validation cohorts consisted of 354 and 96 patients with bacterial pneumonia, respectively. PDR pathogens were isolated in 48 and 21 patients in the derivation and validation cohorts, respectively. The AUROCs of our risk score and the HCAP definition were 0.751 and 0.650, respectively, in the derivation cohort, and were 0.782 and 0.671, respectively, in the validation cohort. The differences between our risk score and the HCAP definition reached statistical significance. A score ≥ 2.5 had the best balance between sensitivity and specificity. Our risk score outperformed the HCAP definition to predict pneumonia caused by PDR pathogens. A history of bronchiectasis or recent hospitalization is the major indication of starting empirical broad-spectrum antibiotics. © 2014 Asian Pacific Society of Respirology.

Metabolic syndrome in a French cohort of patients with bipolar disorder: results from the FACE-BD cohort.

PubMed

Godin, Ophélia; Etain, Bruno; Henry, Chantal; Bougerol, Thierry; Courtet, Philippe; Mayliss, Leroux; Passerieux, Christine; Azorin, Jean-Michel; Kahn, Jean-Pierre; Gard, Sebastien; Costagliola, Dominique; Leboyer, Marion

2014-10-01

The aim of this study was to estimate the prevalence of metabolic syndrome (MetS) and its components in a cohort of French patients with bipolar disorder; determine correlations with sociodemographic, clinical, and treatment-related factors; and investigate the gap between optimal care and effective care of the treated patients. 654 bipolar disorder patients from the FACE-BD cohort were included from 2009 to 2012. Sociodemographic and clinical characteristics, lifestyle information, and data on antipsychotic treatment and comorbidities were collected, and a blood sample was drawn. The Structured Clinical Interview for DSM-IV Axis I Disorders was used to confirm the diagnosis of bipolar disorder. Metabolic syndrome was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. 18.5% of individuals with bipolar disorder met criteria for MetS. Two-thirds of bipolar disorder patients did not receive adequate treatment for MetS components. Multivariate analysis showed that risk of MetS in men was nearly twice that in women (OR = 1.9; 95% CI, 1.0-3.8), and older patients had a 3.5 times higher risk (95% CI, 1.5-7.8) of developing MetS than patients under the age of 35 years. Moreover, patients receiving antipsychotic treatment had a 2.3 times increased risk (95% CI, 1.2-3.5) of having MetS, independent of other potential confounders. The prevalence of MetS is high in bipolar disorder patients, and there was considerable undertreatment of the components of MetS in this population. The prevention and treatment of cardiovascular diseases in these patients should be assessed systematically. The findings highlight the need for integrated care, with more interaction and coordination between psychiatrists and primary care providers. © Copyright 2014 Physicians Postgraduate Press, Inc.

Exploratory factor analysis of self-reported symptoms in a large, population-based military cohort

PubMed Central

2010-01-01

Background US military engagements have consistently raised concern over the array of health outcomes experienced by service members postdeployment. Exploratory factor analysis has been used in studies of 1991 Gulf War-related illnesses, and may increase understanding of symptoms and health outcomes associated with current military conflicts in Iraq and Afghanistan. The objective of this study was to use exploratory factor analysis to describe the correlations among numerous physical and psychological symptoms in terms of a smaller number of unobserved variables or factors. Methods The Millennium Cohort Study collects extensive self-reported health data from a large, population-based military cohort, providing a unique opportunity to investigate the interrelationships of numerous physical and psychological symptoms among US military personnel. This study used data from the Millennium Cohort Study, a large, population-based military cohort. Exploratory factor analysis was used to examine the covariance structure of symptoms reported by approximately 50,000 cohort members during 2004-2006. Analyses incorporated 89 symptoms, including responses to several validated instruments embedded in the questionnaire. Techniques accommodated the categorical and sometimes incomplete nature of the survey data. Results A 14-factor model accounted for 60 percent of the total variance in symptoms data and included factors related to several physical, psychological, and behavioral constructs. A notable finding was that many factors appeared to load in accordance with symptom co-location within the survey instrument, highlighting the difficulty in disassociating the effects of question content, location, and response format on factor structure. Conclusions This study demonstrates the potential strengths and weaknesses of exploratory factor analysis to heighten understanding of the complex associations among symptoms. Further research is needed to investigate the relationship between

Validation sampling can reduce bias in healthcare database studies: an illustration using influenza vaccination effectiveness

PubMed Central

Nelson, Jennifer C.; Marsh, Tracey; Lumley, Thomas; Larson, Eric B.; Jackson, Lisa A.; Jackson, Michael

2014-01-01

Objective Estimates of treatment effectiveness in epidemiologic studies using large observational health care databases may be biased due to inaccurate or incomplete information on important confounders. Study methods that collect and incorporate more comprehensive confounder data on a validation cohort may reduce confounding bias. Study Design and Setting We applied two such methods, imputation and reweighting, to Group Health administrative data (full sample) supplemented by more detailed confounder data from the Adult Changes in Thought study (validation sample). We used influenza vaccination effectiveness (with an unexposed comparator group) as an example and evaluated each method’s ability to reduce bias using the control time period prior to influenza circulation. Results Both methods reduced, but did not completely eliminate, the bias compared with traditional effectiveness estimates that do not utilize the validation sample confounders. Conclusion Although these results support the use of validation sampling methods to improve the accuracy of comparative effectiveness findings from healthcare database studies, they also illustrate that the success of such methods depends on many factors, including the ability to measure important confounders in a representative and large enough validation sample, the comparability of the full sample and validation sample, and the accuracy with which data can be imputed or reweighted using the additional validation sample information. PMID:23849144

Development and validation of a surgical-pathologic staging and scoring system for cervical cancer

PubMed Central

Zhou, Hang; Tang, Fangxu; Jia, Yao; Hu, Ting; Sun, Haiying; Yang, Ru; Chen, Yile; Cheng, Xiaodong; Lv, Weiguo; Wu, Li; Zhou, Jin; Wang, Shaoshuai; Huang, Kecheng; Wang, Lin; Yao, Yuan; Yang, Qifeng; Yang, Xingsheng; Zhang, Qinghua; Han, Xiaobing; Lin, Zhongqiu; Xing, Hui; Qu, Pengpeng; Cai, Hongbing; Song, Xiaojie; Tian, Xiaoyu; Shen, Jian; Xi, Ling; Li, Kezhen; Deng, Dongrui; Wang, Hui; Wang, Changyu; Wu, Mingfu; Zhu, Tao; Chen, Gang; Gao, Qinglei; Wang, Shixuan; Hu, Junbo; Kong, Beihua; Xie, Xing; Ma, Ding

2016-01-01

Background Most cervical cancer patients worldwide receive surgical treatments, and yet the current International Federation of Gynecology and Obstetrics (FIGO) staging system do not consider surgical-pathologic data. We propose a more comprehensive and prognostically valuable surgical-pathologic staging and scoring system (SPSs). Methods Records from 4,220 eligible cervical cancer cases (Cohort 1) were screened for surgical-pathologic risk factors. We constructed a surgical-pathologic staging and SPSs, which was subsequently validated in a prospective study of 1,104 cervical cancer patients (Cohort 2). Results In Cohort 1, seven independent risk factors were associated with patient outcome: lymph node metastasis (LNM), parametrial involvement, histological type, grade, tumor size, stromal invasion, and lymph-vascular space invasion (LVSI). The FIGO staging system was revised and expanded into a surgical-pathologic staging system by including additional criteria of LNM, stromal invasion, and LVSI. LNM was subdivided into three categories based on number and location of metastases. Inclusion of all seven prognostic risk factors improves practical applicability. Patients were stratified into three SPSs risk categories: zero-, low-, and high-score with scores of 0, 1 to 3, and ≥4 (P=1.08E-45; P=6.15E-55). In Cohort 2, 5-year overall survival (OS) and disease-free survival (DFS) outcomes decreased with increased SPSs scores (P=9.04E-15; P=3.23E-16), validating the approach. Surgical-pathologic staging and SPSs show greater homogeneity and discriminatory utility than FIGO staging. Conclusions Surgical-pathologic staging and SPSs improve characterization of tumor severity and disease invasion, which may more accurately predict outcome and guide postoperative therapy. PMID:27014971

Validation of a brief form of the Perceived Neighborhood Social Cohesion questionnaire.

PubMed

Dupuis, Marc; Baggio, Stéphanie; Gmel, Gerhard

2017-02-01

The aim of this study was the validation of a brief form of the Perceived Neighborhood Social Cohesion questionnaire using data from 5065 men from the "Cohort Study on Substance-Use Risk Factors." A 9-item scale covering three factors was proposed. Excellent indices of internal consistency were measured (α = .93). The confirmatory factor analyses resulted in acceptable fit indices supporting measurement invariance across French and German forms. Significant correlations were found between the brief form of the Perceived Neighborhood Social Cohesion questionnaire, and satisfaction and self-reported health, providing evidence of the concurrent validity of the scale. Perceived neighborhood social cohesion, and depression and suicide attempts were negatively associated, sustaining the protective effect of perceived social cohesion.

Validation of periodontitis screening model using sociodemographic, systemic, and molecular information in a Korean population.

PubMed

Kim, Hyun-Duck; Sukhbaatar, Munkhzaya; Shin, Myungseop; Ahn, Yoo-Been; Yoo, Wook-Sung

2014-12-01

This study aims to evaluate and validate a periodontitis screening model that includes sociodemographic, metabolic syndrome (MetS), and molecular information, including gingival crevicular fluid (GCF), matrix metalloproteinase (MMP), and blood cytokines. The authors selected 506 participants from the Shiwha-Banwol cohort: 322 participants from the 2005 cohort for deriving the screening model and 184 participants from the 2007 cohort for its validation. Periodontitis was assessed by dentists using the community periodontal index. Interleukin (IL)-6, IL-8, and tumor necrosis factor-α in blood and MMP-8, -9, and -13 in GCF were assayed using enzyme-linked immunosorbent assay. MetS was assessed by physicians using physical examination and blood laboratory data. Information about age, sex, income, smoking, and drinking was obtained by interview. Logistic regression analysis was applied to finalize the best-fitting model and validate the model using sensitivity, specificity, and c-statistics. The derived model for periodontitis screening had a sensitivity of 0.73, specificity of 0.85, and c-statistic of 0.86 (P <0.001); those of the validated model were 0.64, 0.91, and 0.83 (P <0.001), respectively. The model that included age, sex, income, smoking, drinking, and blood and GCF biomarkers could be useful in screening for periodontitis. A future prospective study is indicated for evaluating this model's ability to predict the occurrence of periodontitis.

Derivation and validation of the prolonged length of stay score in acute stroke patients.

PubMed

Koton, S; Bornstein, N M; Tsabari, R; Tanne, D

2010-05-11

Length of stay (LOS) is the main cost-determining factor of hospitalization of stroke patients. Our aim was to derive and validate a simple score for the assessment of the risk of prolonged LOS for acute stroke patients in a national setting. Ischemic stroke (IS) and intracerebral hemorrhage (ICH) patients in the National Acute Stroke Israeli Surveys (NASIS 2004 and 2007) were included. Predictors of prolonged LOS (LOS > or =7 days) in the NASIS 2004 (n = 1,700) were identified with logistic regression analysis and used for the derivation of the Prolonged Length of Stay (PLOS) score. The score was validated in the NASIS 2007 (n = 1,648). Median (interquartile range) LOS was 6 (3-10) days in the derivation cohort (42.3% prolonged LOS) and 5 (3-8) in the validation cohort (35.7% prolonged LOS). The derivation cohort included 54.8% men, 90.8% IS and 9.2% ICH, with a mean (SD) age of 71.2 (12.5) years. Stroke severity was the strongest multivariable predictor of prolonged LOS: odds ratio (95% confidence interval [CI]) increased from 2.6 (2.0-3.3) for NIH Stroke Scale score (NIHSS) 6-10 to 4.9 (3.0-8.0) for NIHSS 16-20, compared with NIHSS < or =5. Stroke severity and type, decreased level of consciousness on admission, history of congestive heart failure, and prior atrial fibrillation were used for the derivation of the PLOS score (c statistics 0.692, 95% CI 0.666-0.718). The score performed similarly well in the validation cohort (c statistics 0.680, 95% CI 0.653-0.707). A simple prolonged length of stay score, based on available baseline information, may be useful for tailoring policy aimed at better use of resources and optimal discharge planning of acute stroke patients.

Determinants of breast-feeding in a Finnish birth cohort.

PubMed

Erkkola, Maijaliisa; Salmenhaara, Maija; Kronberg-Kippilä, Carina; Ahonen, Suvi; Arkkola, Tuula; Uusitalo, Liisa; Pietinen, Pirjo; Veijola, Riitta; Knip, Mikael; Virtanen, Suvi M

2010-04-01

To assess milk feeding on the maternity ward and during infancy, and their relationship to sociodemographic determinants. The validity of our 3-month questionnaire in measuring hospital feeding was assessed. A prospective Finnish birth cohort with increased risk to type 1 diabetes recruited between 1996 and 2004. The families completed a follow-up form on the age at introduction of new foods and age-specific dietary questionnaires. Type 1 Diabetes Prediction and Prevention (DIPP) project, Finland. A cohort of 5993 children (77 % of those invited) participated in the main study, and 117 randomly selected infants in the validation study. Breast milk was the predominant milk on the maternity ward given to 99 % of the infants. Altogether, 80 % of the women recalled their child being fed supplementary milk (donated breast milk or infant formula) on the maternity ward. The median duration of exclusive breast-feeding was 1.4 months (range 0-8) and that of total breast-feeding 7.0 months (0-25). Additional milk feeding on the maternity ward, short parental education, maternal smoking during pregnancy, small gestational age and having no siblings were associated with a risk of short duration of both exclusive and total breast-feeding. In the validation study, 78 % of the milk types given on the maternity ward fell into the same category, according to the questionnaire and hospital records. The recommendations for infant feeding were not achieved. Infant feeding is strongly influenced by sociodemographic determinants and feeding practices on the maternity wards. Long-term breast-feeding may be supported by active promotion on the maternity ward.

A Cohort, Is a Cohort, Is a Cohort...or Is It?

ERIC Educational Resources Information Center

Pemberton, Cynthia Lee A.; Akkary, Rima Karami

2010-01-01

This paper presents findings from a multi-year qualitative study based upon life-history narratives of women pursuing doctoral degrees in Educational Leadership. This paper focuses on findings specific to educational cohort models, and suggests that perhaps, at least for women, naturally emergent cohorts--born of relationships of choice--may be…

Diagnostic impact of routine Lyme serology in recent-onset arthritis: results from the ESPOIR cohort

PubMed Central

Guellec, Dewi; Narbonne, Valérie; Cornec, Divi; Marhadour, Thierry; Varache, Sophie; Dougados, Maxime; Daurès, Jean Pierre; Jousse-Joulin, Sandrine; Devauchelle-Pensec, Valérie; Saraux, Alain

2016-01-01

Objectives Lyme disease may be considered by rheumatologists in patients with recent-onset arthritis, even in the absence of suggestive symptoms. The aim of this study was to determine the diagnostic impact of routine Lyme serology in a French cohort of patients with recent-onset arthritis affecting at least 2 joints. Methods We performed an ancillary study of a French prospective multicentre cohort established to monitor clinical, biological and radiographic data in patients with inflammatory arthritis in at least 2 joints, lasting for 6 weeks to 6 months. Borrelia IgM and IgG antibodies were sought routinely at baseline, using ELISA tests, independently from the physician's strategy for detecting a spirochetal infection. We recorded the proportion of patients with a final diagnosis of Lyme arthritis and evaluated the diagnostic performance of Lyme serology in this particular context. The clinical and biological characteristics of patients according to the Lyme serology results were analysed. Results Of 810 patients, 657 (81.1%) were negative for IgM and IgG antibodies, 91 (11.2%) had only IgM antibodies, 49 (6%) had only IgG antibodies, and 13 (1.6%) had IgG and IgM antibodies. Thus, 7.6% had IgG positivity, consistent with exposure to Borrelia infection. IgG positivity was significantly more prevalent in the North and North-East regions of France (χ2=14.6, p<0.001). No patients received a definite diagnosis of Lyme arthritis. Conclusions This study does not support routine Lyme serological testing in patients with recent-onset inflammatory arthritis affecting more than 1 joint. PMID:26819751

A score to predict and stratify risk of tuberculosis in adult contacts of tuberculosis index cases: a prospective derivation and external validation cohort study.

PubMed

Saunders, Matthew J; Wingfield, Tom; Tovar, Marco A; Baldwin, Matthew R; Datta, Sumona; Zevallos, Karine; Montoya, Rosario; Valencia, Teresa R; Friedland, Jon S; Moulton, Larry H; Gilman, Robert H; Evans, Carlton A

2017-11-01

Contacts of tuberculosis index cases are at increased risk of developing tuberculosis. Screening, preventive therapy, and surveillance for tuberculosis are underused interventions in contacts, particularly adults. We developed a score to predict risk of tuberculosis in adult contacts of tuberculosis index cases. In 2002-06, we recruited contacts aged 15 years or older of index cases with pulmonary tuberculosis who lived in desert shanty towns in Ventanilla, Peru. We followed up contacts for tuberculosis until February, 2016. We used a Cox proportional hazards model to identify index case, contact, and household risk factors for tuberculosis from which to derive a score and classify contacts as low, medium, or high risk. We validated the score in an urban community recruited in Callao, Peru, in 2014-15. In the derivation cohort, we identified 2017 contacts of 715 index cases, and median follow-up was 10·7 years (IQR 9·5-11·8). 178 (9%) of 2017 contacts developed tuberculosis during 19 147 person-years of follow-up (incidence 0·93 per 100 person-years, 95% CI 0·80-1·08). Risk factors for tuberculosis were body-mass index, previous tuberculosis, age, sustained exposure to the index case, the index case being in a male patient, lower community household socioeconomic position, indoor air pollution, previous tuberculosis among household members, and living in a household with a low number of windows per room. The 10-year risks of tuberculosis in the low-risk, medium-risk, and high-risk groups were, respectively, 2·8% (95% CI 1·7-4·4), 6·2% (4·8-8·1), and 20·6% (17·3-24·4). The 535 (27%) contacts classified as high risk accounted for 60% of the tuberculosis identified during follow-up. The score predicted tuberculosis independently of tuberculin skin test and index-case drug sensitivity results. In the external validation cohort, 65 (3%) of 1910 contacts developed tuberculosis during 3771 person-years of follow-up (incidence 1·7 per 100 person-years, 95

Evaluation of a Questionnaire to Assess Sedentary and Active Behaviors in the Southern Community Cohort Study

PubMed Central

Buchowski, Maciej S.; Matthews, Charles E.; Cohen, Sarah S.; Signorello, Lisa B.; Fowke, Jay H.; Hargreaves, Margaret K.; Schlundt, David G.; Blot, William J.

2012-01-01

Background Low physical activity (PA) is linked to cancer and other diseases prevalent in racial/ethnic minorities and low-income populations. This study evaluated the PA questionnaire (PAQ) used in the Southern Cohort Community Study, a prospective investigation of health disparities between African-American and white adults. Methods The PAQ was administered upon entry into the cohort (PAQ1) and after 12–15 months (PAQ2) in 118 participants (40–60 year-old, 48% male, 74% African-American). Test-retest reliability (PAQ1 versus PAQ2) was assessed using Spearman correlations and the Wilcoxon signed rank test. Criterion validity of the PAQ was assessed via comparison with a PA monitor and a last-month PA survey (LMPAS), administered up to 4 times in the study period. Results The PAQ test-retest reliability ranged from 0.25–0.54 for sedentary behaviors and 0.22–0.47 for active behaviors. The criterion validity for the PAQ compared with PA monitor ranged from 0.21–0.24 for sedentary behaviors and from 0.17–0.31 for active behaviors. There was general consistency in the magnitude of correlations between the PAQ and PA-monitor between African-Americans and whites. Conclusions The SCCS-PAQ has fair to moderate test-retest reliability and demonstrated some evidence of criterion validity for ranking participants by their level of sedentary and active behaviors. PMID:21952413

Chlamydia trachomatis versus common uropathogens as a cause of chronic bacterial prostatitis: Is there any difference? Results of a prospective parallel-cohort study

PubMed Central

Pisano, Francesca; Nesi, Gabriella; Magri, Vittorio; Verze, Paolo; Perletti, Gianpaolo; Gontero, Paolo; Mirone, Vincenzo; Bartoletti, Riccardo

2017-01-01

Purpose The role of Chlamydia trachomatis (CT) infection in chronic bacterial prostatitis (CBP) is well known. What is unclear is whether there are any differences in the course or clinical outcome of the disease when the cause is CT or other uropathogens. Materials and Methods A series of 311 patients affected by CBP due to CT (cohort A) was compared with a group of 524 patients affected by CBP caused by common uropathogen bacteria (cohort B). All participants completed the following questionnaires: National Institutes of Health Chronic Prostatitis Symptom Index, International Prostate Symptom Score, International Index of Erectile Function-15 erectile function domain (IIEF-15-EFD), Premature Ejaculation Diagnostic Tool (PEDT), and the Short Form 36 (SF-36) Health Survey. All patients were followed with clinical and microbiological evaluations. Results After a mean follow-up time of 42.3 months, the number of symptomatic episodes was significantly higher in patients in cohort A than in cohort B (4.1±1.1 vs. 2.8±0.8, p<0.001), and the mean time to first symptomatic recurrence was shorter in cohort A than in cohort B (3.3±2.3 months vs. 5.7±1.9 months, p<0.001). Moreover, scores on the SF-36 tool were significantly lower in cohort A (96.5±1.0 vs. 99.7±1.9, p<0.001) at the first symptomatic recurrence. Cohort A also showed significantly lower scores on the IIEF-15-EFD and PEDT questionnaires at the end of the follow-up period (26.8±2.9 vs. 27.3±3.3, p=0.02 and 11.5±2.3 vs. 4.5±2.8, p<0.001, respectively). Conclusions Patients affected by CBP due to CT infection have a higher number of symptomatic recurrences with a more severe impact on quality of life. PMID:29124247

Perfluoroalkyl Substances During Pregnancy and Validated Preeclampsia Among Nulliparous Women in the Norwegian Mother and Child Cohort Study

PubMed Central

Starling, Anne P.; Engel, Stephanie M.; Richardson, David B.; Baird, Donna D.; Haug, Line S.; Stuebe, Alison M.; Klungsøyr, Kari; Harmon, Quaker; Becher, Georg; Thomsen, Cathrine; Sabaredzovic, Azemira; Eggesbø, Merete; Hoppin, Jane A.; Travlos, Gregory S.; Wilson, Ralph E.; Trogstad, Lill I.; Magnus, Per; Longnecker, Matthew P.

2014-01-01

Perfluoroalkyl substances (PFAS) are persistent and ubiquitous environmental contaminants, and human exposure to these substances may be related to preeclampsia, a common pregnancy complication. Previous studies have found serum concentrations of PFAS to be positively associated with pregnancy-induced hypertension and preeclampsia in a population with high levels of exposure to perfluorooctanoate. Whether this association exists among pregnant women with background levels of PFAS exposure is unknown. Using data from the Norwegian Mother and Child Cohort Study conducted by the Norwegian Institute of Public Health, we carried out a study of nulliparous pregnant women enrolled in 2003–2007 (466 cases, 510 noncases) to estimate associations between PFAS concentrations and an independently validated diagnosis of preeclampsia. We measured levels of 9 PFAS in maternal plasma extracted midpregnancy; statistical analyses were restricted to 7 PFAS that were quantifiable in more than 50% of samples. In proportional hazards models adjusted for maternal age, prepregnancy body mass index (weight (kg)/height (m)2), educational level, and smoking status, we observed no strongly positive associations between PFAS levels and preeclampsia. We found an inverse association between preeclampsia and the highest quartile of perfluoroundecanoic acid concentration relative to the lowest quartile (hazard ratio = 0.55, 95% confidence interval: 0.38, 0.81). Overall, our findings do not support an increased risk of preeclampsia among nulliparous Norwegian women with background levels of PFAS exposure. PMID:24557813

Perfluoroalkyl substances during pregnancy and validated preeclampsia among nulliparous women in the Norwegian Mother and Child Cohort Study.

PubMed

Starling, Anne P; Engel, Stephanie M; Richardson, David B; Baird, Donna D; Haug, Line S; Stuebe, Alison M; Klungsøyr, Kari; Harmon, Quaker; Becher, Georg; Thomsen, Cathrine; Sabaredzovic, Azemira; Eggesbø, Merete; Hoppin, Jane A; Travlos, Gregory S; Wilson, Ralph E; Trogstad, Lill I; Magnus, Per; Longnecker, Matthew P

2014-04-01

Perfluoroalkyl substances (PFAS) are persistent and ubiquitous environmental contaminants, and human exposure to these substances may be related to preeclampsia, a common pregnancy complication. Previous studies have found serum concentrations of PFAS to be positively associated with pregnancy-induced hypertension and preeclampsia in a population with high levels of exposure to perfluorooctanoate. Whether this association exists among pregnant women with background levels of PFAS exposure is unknown. Using data from the Norwegian Mother and Child Cohort Study conducted by the Norwegian Institute of Public Health, we carried out a study of nulliparous pregnant women enrolled in 2003-2007 (466 cases, 510 noncases) to estimate associations between PFAS concentrations and an independently validated diagnosis of preeclampsia. We measured levels of 9 PFAS in maternal plasma extracted midpregnancy; statistical analyses were restricted to 7 PFAS that were quantifiable in more than 50% of samples. In proportional hazards models adjusted for maternal age, prepregnancy body mass index (weight (kg)/height (m)(2)), educational level, and smoking status, we observed no strongly positive associations between PFAS levels and preeclampsia. We found an inverse association between preeclampsia and the highest quartile of perfluoroundecanoic acid concentration relative to the lowest quartile (hazard ratio = 0.55, 95% confidence interval: 0.38, 0.81). Overall, our findings do not support an increased risk of preeclampsia among nulliparous Norwegian women with background levels of PFAS exposure.

Comparison of epicardial adipose tissue radiodensity threshold between contrast and non-contrast enhanced computed tomography scans: A cohort study of derivation and validation.

PubMed

Xu, Lingyu; Xu, Yuancheng; Coulden, Richard; Sonnex, Emer; Hrybouski, Stanislau; Paterson, Ian; Butler, Craig

2018-05-11

Epicardial adipose tissue (EAT) volume derived from contrast enhanced (CE) computed tomography (CT) scans is not well validated. We aim to establish a reliable threshold to accurately quantify EAT volume from CE datasets. We analyzed EAT volume on paired non-contrast (NC) and CE datasets from 25 patients to derive appropriate Hounsfield (HU) cutpoints to equalize two EAT volume estimates. The gold standard threshold (-190HU, -30HU) was used to assess EAT volume on NC datasets. For CE datasets, EAT volumes were estimated using three previously reported thresholds: (-190HU, -30HU), (-190HU, -15HU), (-175HU, -15HU) and were analyzed by a semi-automated 3D Fat analysis software. Subsequently, we applied a threshold correction to (-190HU, -30HU) based on mean differences in radiodensity between NC and CE images (ΔEATrd = CE radiodensity - NC radiodensity). We then validated our findings on EAT threshold in 21 additional patients with paired CT datasets. EAT volume from CE datasets using previously published thresholds consistently underestimated EAT volume from NC dataset standard by a magnitude of 8.2%-19.1%. Using our corrected threshold (-190HU, -3HU) in CE datasets yielded statistically identical EAT volume to NC EAT volume in the validation cohort (186.1 ± 80.3 vs. 185.5 ± 80.1 cm 3 , Δ = 0.6 cm 3 , 0.3%, p = 0.374). Estimating EAT volume from contrast enhanced CT scans using a corrected threshold of -190HU, -3HU provided excellent agreement with EAT volume from non-contrast CT scans using a standard threshold of -190HU, -30HU. Copyright © 2018. Published by Elsevier B.V.

Assessment of two different types of bias affecting the results of outcome-based evaluation in undergraduate medical education

PubMed Central

2014-01-01

Background Estimating learning outcome from comparative student self-ratings is a reliable and valid method to identify specific strengths and shortcomings in undergraduate medical curricula. However, requiring students to complete two evaluation forms (i.e. one before and one after teaching) might adversely affect response rates. Alternatively, students could be asked to rate their initial performance level retrospectively. This approach might threaten the validity of results due to response shift or effort justification bias. Methods Two consecutive cohorts of medical students enrolled in a six-week cardio-respiratory module were enrolled in this study. In both cohorts, performance gain was estimated for 33 specific learning objectives. In the first cohort, outcomes calculated from ratings provided before (pretest) and after (posttest) teaching were compared to outcomes derived from comparative self-ratings collected after teaching only (thentest and posttest). In the second cohort, only thentests and posttests were used to calculate outcomes, but data collection tools differed with regard to item presentation. In one group, thentest and posttest ratings were obtained sequentially on separate forms while in the other, both ratings were obtained simultaneously for each learning objective. Results Using thentest ratings to calculate performance gain produced slightly higher values than using true pretest ratings. Direct comparison of then- and posttest ratings also yielded slightly higher performance gain than sequential ratings, but this effect was negligibly small. Conclusions Given the small effect sizes, using thentests appears to be equivalent to using true pretest ratings. Item presentation in the posttest does not significantly impact on results. PMID:25043503

Dynamic Time Warping compared to established methods for validation of musculoskeletal models.

PubMed

Gaspar, Martin; Welke, Bastian; Seehaus, Frank; Hurschler, Christof; Schwarze, Michael

2017-04-11

By means of Multi-Body musculoskeletal simulation, important variables such as internal joint forces and moments can be estimated which cannot be measured directly. Validation can ensued by qualitative or by quantitative methods. Especially when comparing time-dependent signals, many methods do not perform well and validation is often limited to qualitative approaches. The aim of the present study was to investigate the capabilities of the Dynamic Time Warping (DTW) algorithm for comparing time series, which can quantify phase as well as amplitude errors. We contrast the sensitivity of DTW with other established metrics: the Pearson correlation coefficient, cross-correlation, the metric according to Geers, RMSE and normalized RMSE. This study is based on two data sets, where one data set represents direct validation and the other represents indirect validation. Direct validation was performed in the context of clinical gait-analysis on trans-femoral amputees fitted with a 6 component force-moment sensor. Measured forces and moments from amputees' socket-prosthesis are compared to simulated forces and moments. Indirect validation was performed in the context of surface EMG measurements on a cohort of healthy subjects with measurements taken of seven muscles of the leg, which were compared to simulated muscle activations. Regarding direct validation, a positive linear relation between results of RMSE and nRMSE to DTW can be seen. For indirect validation, a negative linear relation exists between Pearson correlation and cross-correlation. We propose the DTW algorithm for use in both direct and indirect quantitative validation as it correlates well with methods that are most suitable for one of the tasks. However, in DV it should be used together with methods resulting in a dimensional error value, in order to be able to interpret results more comprehensible. Copyright © 2017 Elsevier Ltd. All rights reserved.

Aromatase Inhibitor-Associated Bone Fractures: A Case-Cohort GWAS and Functional Genomics

PubMed Central

Liu, Mohan; Goss, Paul E.; Ingle, James N.; Kubo, Michiaki; Furukawa, Yoichi; Batzler, Anthony; Jenkins, Gregory D.; Carlson, Erin E.; Nakamura, Yusuke; Schaid, Daniel J.; Chapman, Judy-Anne W.; Shepherd, Lois E.; Ellis, Matthew J.; Khosla, Sundeep; Wang, Liewei

2014-01-01

Bone fractures are a major consequence of osteoporosis. There is a direct relationship between serum estrogen concentrations and osteoporosis risk. Aromatase inhibitors (AIs) greatly decrease serum estrogen levels in postmenopausal women, and increased incidence of fractures is a side effect of AI therapy. We performed a discovery case-cohort genome-wide association study (GWAS) using samples from 1071 patients, 231 cases and 840 controls, enrolled in the MA.27 breast cancer AI trial to identify genetic factors involved in AI-related fractures, followed by functional genomic validation. Association analyses identified 20 GWAS single nucleotide polymorphism (SNP) signals with P < 5E-06. After removal of signals in gene deserts and those composed entirely of imputed SNPs, we applied a functional validation “decision cascade” that resulted in validation of the CTSZ-SLMO2-ATP5E, TRAM2-TMEM14A, and MAP4K4 genes. These genes all displayed estradiol (E2)-dependent induction in human fetal osteoblasts transfected with estrogen receptor-α, and their knockdown altered the expression of known osteoporosis-related genes. These same genes also displayed SNP-dependent variation in E2 induction that paralleled the SNP-dependent induction of known osteoporosis genes, such as osteoprotegerin. In summary, our case-cohort GWAS identified SNPs in or near CTSZ-SLMO2-ATP5E, TRAM2-TMEM14A, and MAP4K4 that were associated with risk for bone fracture in estrogen receptor-positive breast cancer patients treated with AIs. These genes displayed E2-dependent induction, their knockdown altered the expression of genes related to osteoporosis, and they displayed SNP genotype-dependent variation in E2 induction. These observations may lead to the identification of novel mechanisms associated with fracture risk in postmenopausal women treated with AIs. PMID:25148458

Cohort versus Non-Cohort High School Students' Math Performance: Achievement Test Scores and Coursework

ERIC Educational Resources Information Center

Parke, Carol S.; Keener, Dana

2011-01-01

The purpose of this study is to compare multiple measures of mathematics achievement for 1,378 cohort students who attended the same high school in a district from 9th to 12th grade with non-cohort students in each grade level. Results show that mobility had an impact on math achievement. After accounting for gender, ethnicity, and SES, adjusted…

Derivation and validation of a two-biomarker panel for diagnosis of ARDS in patients with severe traumatic injuries.

PubMed

Ware, Lorraine B; Zhao, Zhiguo; Koyama, Tatsuki; Brown, Ryan M; Semler, Matthew W; Janz, David R; May, Addison K; Fremont, Richard D; Matthay, Michael A; Cohen, Mitchell J; Calfee, Carolyn S

2017-01-01

Acute respiratory distress syndrome (ARDS) is common after severe traumatic injuries but is underdiagnosed and undertreated. We hypothesized that a panel of plasma biomarkers could be used to diagnose ARDS in severe trauma. To test this hypothesis, we derived and validated a biomarker panel in three independent cohorts and compared the diagnostic performance to clinician recognition of ARDS. Eleven plasma biomarkers of inflammation, lung epithelial and endothelial injury were measured in a derivation cohort of 439 severe trauma patients. ARDS status was analyzed by two-investigator consensus, and cases were required to meet Berlin criteria on intensive care unit (ICU) day 1. Controls were subjects without ARDS during the first 4 days of study enrollment. A multivariable logistic regression model was used to generate probabilities for ARDS. A reduced model with the top two performing markers was then tested in two independent validation cohorts. To assess clinical diagnosis of ARDS, medical records in the derivation cohort were systematically searched for documentation of ARDS diagnosis made by a clinical provider. Among 11 biomarkers, the combination of the endothelial injury marker angiopoietin-2 (Ang-2) and the lung epithelial injury marker receptor for advanced glycation endproducts (RAGE) provided good discrimination for ARDS in the derivation cohort (area under the curve (AUC)=0.74 (95% CI 0.67 to 0.80). In the validation cohorts, the AUCs for this model were 0.70 (0.61 to 0.77) and 0.78 (0.71 to 0.84). In contrast, provider assessment demonstrated poor diagnostic accuracy for ARDS, with AUC of 0.55 (0.51 to 0.60). A two-biomarker panel consisting of Ang-2 and RAGE performed well across multiple patient cohorts and outperformed clinical providers for diagnosing ARDS in severe trauma. Clinical application of this model could improve both diagnosis and treatment of ARDS in patients with severe trauma. Diagnostic study, level II.

Factors associated with a bad functional prognosis in early inflammatory back pain: results from the DESIR cohort.

PubMed

Lukas, C; Dougados, M; Combe, B

2016-01-01

Spondyloarthritis (SpA) is a heterogeneous disease with hardly predictable potential courses. We aimed at determining prognostic factors of bad functional outcome at 2 years in patients with early inflammatory back pain (IBP). Data from patients included in the French multicentre devenir des spondylarthropathies indifférenciées récentes (DESIR) cohort, that is, suffering from IBP starting before 50 years of age and lasting for 3-36 months, were used. A bad functional outcome at 24 months was defined as an increase in bath ankylosing spondylitis functional index (BASFI), or BASFI at 2 years higher than the 75th centile in the cohort. Demographic, clinical, biological and radiological data collected at inclusion were compared in patients with bad functional outcome versus others, by χ(2) test, then by a multivariate logistic regression model with stepwise selection of relevant factors. 513 patients (54.4% females, 72.2% fulfilling ASAS criteria) were assessed. Of those, 130 (25.3%) fulfilled the aforementioned criteria of a bad functional outcome (BASFI increase ≥4 units or ≥36 at 2 years). Multivariate analysis revealed that not fulfilling ASAS criteria, female sex, age >33 years, lower educational level, active smoking status and high disease activity according to bath ankylosing spondylitis disease activity index (BASDAI) at baseline were independently associated with a bad functional outcome at 24 months. Sensitivity analyses restricted to patients fulfilling ASAS criteria for SpA resulted in similar results. We observed, in a large prospective cohort of patients with early IBP, formerly described bad prognostic factors, especially a low educational level, an older age and a high disease activity at onset, and revealed that active smoking status and female sex were also independently associated with a poor outcome. Fulfilment of ASAS criteria, on the other hand, was predictive of a better outcome, most likely due to the more consensual

Increasing Use of Nonmedical Analgesics Among Younger Cohorts in the United States: A Birth Cohort Effect

PubMed Central

Miech, Richard; Bohnert, Amy; Heard, Kennon; Boardman, Jason

2017-01-01

Purpose Nonmedical use of prescription pain drugs (hereafter ‘analgesics’) has increased substantially in recent years. It is not known whether today’s youth are disproportionately driving this increase or, instead, the trend is a general one that has affected cohorts of all ages similarly. To address this question we present the first age-period-cohort analysis of nonmedical use of analgesics. Methods Data come from the National Survey on Drug Use and Health, a series of annual, nationally-representative, cross-sectional surveys of the U.S. civilian, non-institutionalized population. The analysis focuses on the years 1985 to 2009 and uses the recently developed ‘intrinsic estimator’ algorithm to disentangle age-period-cohort effects. Results Substantial increases in the prevalence of nonmedical analgesics use have occurred across all cohorts and ages in recent years, but this increase is significantly amplified among today’s adolescents. The odds of past-year, nonmedical analgesics use for today’s youngest cohort (born 1980–1994) are higher than would be expected on the basis of their age and broad, historical period influences that have increased use across people of all ages and cohorts. The independent influence of cohort on past-year, nonmedical analgesics use is about 40% higher for today’s youth cohort than any of the cohorts that came before them. This finding is present among men, women, non-Hispanic whites, non-Hispanic blacks, and Hispanics. Conclusions Although nonmedical use of analgesics is evident among all ages, cohorts, and periods, today’s younger cohorts warrant special attention for substance abuse policies and interventions targeted at reversing the increase in nonmedical analgesics use. PMID:23260832

Comparing profiles of mental disorder across birth cohorts: results from the 2007 Australian National Survey of Mental Health and Wellbeing.

PubMed

Sunderland, Matthew; Carragher, Natacha; Buchan, Heather; Batterham, Philip J; Slade, Tim

2014-05-01

To describe and compare individuals with any DSM-IV mental disorder from three different birth cohorts - young (16-34 years), middle age (35-59 years) and older age (60-85 years) - on a range of clinically relevant factors. Data were derived from the 2007 Australian National Survey of Mental Health and Wellbeing. Individuals from three birth cohorts with a range of mental health and substance use disorders were identified using DSM-IV criteria and compared using regression analysis. The specific factors that were compared include: (1) type of disorder/disorders present; (2) suicidality; (3) number of co-occurring disorders; (4) levels of distress and impairment; (5) self-assessed physical and mental health; (6) presence of physical conditions; (7) size and quality of social support/network; and (8) treatment-seeking behaviour. The birth cohorts differed dramatically in terms of the specific disorders that were present. The older cohort were significantly more likely to experience internalising disorders and significantly less likely to experience externalising disorders in comparison to the young cohort. The older cohort were significantly more likely to experience co-morbid physical conditions as well as lower life satisfaction, poorer self-rated physical health, increased functional impairment, and more days out of role. The younger cohort had a significantly larger peer group that they could confide in and rely on in comparison to the older cohort. Clinicians and researchers need to be cognisant that mental disorders manifest as highly heterogeneous constructs. The presentation of a disorder in a younger individual could be vastly different from the presentation of the same disorder in an older individual. The additional burden associated with these factors and how they apply to different birth cohorts must be taken into consideration when planning mental health services and effective treatment for the general population.

Returning findings within longitudinal cohort studies: the 1958 birth cohort as an exemplar.

PubMed

Wallace, Susan E; Walker, Neil M; Elliott, Jane

2014-01-01

Population-based, prospective longitudinal cohort studies are considering the issues surrounding returning findings to individuals as a result of genomic and other medical research studies. While guidance is being developed for clinical settings, the process is less clear for those conducting longitudinal research. This paper discusses work conducted on behalf of The UK Cohort and Longitudinal Study Enhancement Resource programme (CLOSER) to examine consent requirements, process considerations and specific examples of potential findings in the context of the 1958 British Birth cohort. Beyond deciding which findings to return, there are questions of whether re-consent is needed and the possible impact on the study, how the feedback process will be managed, and what resources are needed to support that process. Recommendations are made for actions a cohort study should consider taking when making vital decisions regarding returning findings. Any decisions need to be context-specific, arrived at transparently, communicated clearly, and in the best interests of both the participants and the study.

Use of atomoxetine and suicidal ideation in children and adolescents: Results of an observational cohort study within general practice in England.

PubMed

Davies, M; Coughtrie, A; Layton, D; Shakir, S A S

2017-01-01

To investigate the association between atomoxetine, a drug used in the treatment of Attention Deficit Hyperactivity Disorder (ADHD), and suicidal ideation, within a cohort of 2-18-year-old patients in England. The study was conducted using the observational cohort technique of Modified prescription event monitoring (M-PEM). Patients prescribed atomoxetine were identified from dispensed prescriptions issued by primary care physicians. A customised postal GP questionnaire was used to capture outcome data for suicidal ideation. A matched pair cohort analysis was performed within patients to compare the risk of suicidal ideation in the period after starting atomoxetine with the risk prior to starting atomoxetine; this was stratified by age and concomitant use of methylphenidate. Additional information on patient characteristics, and events of interest was also collected; individual cases of suicidal ideation were qualitatively assessed for drug relatedness. Of the final cohort (n=4509); 85.5% male (n=3857), median age 11 years (IQR: 9,14). Primary prescribing indication for atomoxetine was ADHD (n=4261, 94.6%). Almost a quarter of the cohort had been co-prescribed methylphenidate. Results of the matched pair cohort analysis indicated that the period after starting atomoxetine was not associated with an increase in the incidence of suicidal ideation compared to the period prior to starting treatment (RR: 0.71; CI: 0.48-1.07; P-value: 0.104). Individual case assessment of suicidal ideation suggested a causal association within a number of cases. This study found no evidence of an increased risk of suicidal ideation during treatment with atomoxetine, compared to the period prior to starting treatment. Amongst age specific subgroups, this risk may change. Nonetheless, individual case assessment suggested a causal relationship in some patients, hence physicians need to be aware of the possibility of developing this event, and furthermore consider how best to detect it in

Development and validation of a prognostic scoring system for patients with chronic myelomonocytic leukemia.

PubMed

Such, Esperanza; Germing, Ulrich; Malcovati, Luca; Cervera, José; Kuendgen, Andrea; Della Porta, Matteo G; Nomdedeu, Benet; Arenillas, Leonor; Luño, Elisa; Xicoy, Blanca; Amigo, Mari L; Valcarcel, David; Nachtkamp, Kathrin; Ambaglio, Ilaria; Hildebrandt, Barbara; Lorenzo, Ignacio; Cazzola, Mario; Sanz, Guillermo

2013-04-11

The natural course of chronic myelomonocytic leukemia (CMML) is highly variable but a widely accepted prognostic scoring system for patients with CMML is not available. The main aim of this study was to develop a new CMML-specific prognostic scoring system (CPSS) in a large series of 558 patients with CMML (training cohort, Spanish Group of Myelodysplastic Syndromes) and to validate it in an independent series of 274 patients (validation cohort, Heinrich Heine University Hospital, Düsseldorf, Germany, and San Matteo Hospital, Pavia, Italy). The most relevant variables for overall survival (OS) and evolution to acute myeloblastic leukemia (AML) were FAB and WHO CMML subtypes, CMML-specific cytogenetic risk classification, and red blood cell (RBC) transfusion dependency. CPSS was able to segregate patients into 4 clearly different risk groups for OS (P < .001) and risk of AML evolution (P < .001) and its predictive capability was confirmed in the validation cohort. An alternative CPSS with hemoglobin instead of RBC transfusion dependency offered almost identical prognostic capability. This study confirms the prognostic impact of FAB and WHO subtypes, recognizes the importance of RBC transfusion dependency and cytogenetics, and offers a simple and powerful CPSS for accurately assessing prognosis and planning therapy in patients with CMML.

Analysis procedures and subjective flight results of a simulator validation and cue fidelity experiment

NASA Technical Reports Server (NTRS)

Carr, Peter C.; Mckissick, Burnell T.

1988-01-01

A joint experiment to investigate simulator validation and cue fidelity was conducted by the Dryden Flight Research Facility of NASA Ames Research Center (Ames-Dryden) and NASA Langley Research Center. The primary objective was to validate the use of a closed-loop pilot-vehicle mathematical model as an analytical tool for optimizing the tradeoff between simulator fidelity requirements and simulator cost. The validation process includes comparing model predictions with simulation and flight test results to evaluate various hypotheses for differences in motion and visual cues and information transfer. A group of five pilots flew air-to-air tracking maneuvers in the Langley differential maneuvering simulator and visual motion simulator and in an F-14 aircraft at Ames-Dryden. The simulators used motion and visual cueing devices including a g-seat, a helmet loader, wide field-of-view horizon, and a motion base platform.

Self-selection and bias in a large prospective pregnancy cohort in Norway.

PubMed

Nilsen, Roy M; Vollset, Stein Emil; Gjessing, Håkon K; Skjaerven, Rolv; Melve, Kari K; Schreuder, Patricia; Alsaker, Elin R; Haug, Kjell; Daltveit, Anne Kjersti; Magnus, Per

2009-11-01

Self-selection in epidemiological studies may introduce selection bias and influence the validity of study results. To evaluate potential bias due to self-selection in a large prospective pregnancy cohort in Norway, the authors studied differences in prevalence estimates and association measures between study participants and all women giving birth in Norway. Women who agreed to participate in the Norwegian Mother and Child Cohort Study (43.5% of invited; n = 73 579) were compared with all women giving birth in Norway (n = 398 849) using data from the population-based Medical Birth Registry of Norway in 2000-2006. Bias in the prevalence of 23 exposure and outcome variables was measured as the ratio of relative frequencies, whereas bias in exposure-outcome associations of eight relationships was measured as the ratio of odds ratios. Statistically significant relative differences in prevalence estimates between the cohort participants and the total population were found for all variables, except for maternal epilepsy, chronic hypertension and pre-eclampsia. There was a strong under-representation of the youngest women (<25 years), those living alone, mothers with more than two previous births and with previous stillbirths (relative deviation 30-45%). In addition, smokers, women with stillbirths and neonatal death were markedly under-represented in the cohort (relative deviation 22-43%), while multivitamin and folic acid supplement users were over-represented (relative deviation 31-43%). Despite this, no statistically relative differences in association measures were found between participants and the total population regarding the eight exposure-outcome associations. Using data from the Medical Birth Registry of Norway, this study suggests that prevalence estimates of exposures and outcomes, but not estimates of exposure-outcome associations are biased due to self-selection in the Norwegian Mother and Child Cohort Study.

Development and validation of a prognostic index for 4-year mortality in older adults.

PubMed

Lee, Sei J; Lindquist, Karla; Segal, Mark R; Covinsky, Kenneth E

2006-02-15

Both comorbid conditions and functional measures predict mortality in older adults, but few prognostic indexes combine both classes of predictors. Combining easily obtained measures into an accurate predictive model could be useful to clinicians advising patients, as well as policy makers and epidemiologists interested in risk adjustment. To develop and validate a prognostic index for 4-year mortality using information that can be obtained from patient report. Using the 1998 wave of the Health and Retirement Study (HRS), a population-based study of community-dwelling US adults older than 50 years, we developed the prognostic index from 11,701 individuals and validated the index with 8009. Individuals were asked about their demographic characteristics, whether they had specific diseases, and whether they had difficulty with a series of functional measures. We identified variables independently associated with mortality and weighted the variables to create a risk index. Death by December 31, 2002. The overall response rate was 81%. During the 4-year follow-up, there were 1361 deaths (12%) in the development cohort and 1072 deaths (13%) in the validation cohort. Twelve independent predictors of mortality were identified: 2 demographic variables (age: 60-64 years, 1 point; 65-69 years, 2 points; 70-74 years, 3 points; 75-79 years, 4 points; 80-84 years, 5 points, >85 years, 7 points and male sex, 2 points), 6 comorbid conditions (diabetes, 1 point; cancer, 2 points; lung disease, 2 points; heart failure, 2 points; current tobacco use, 2 points; and body mass index <25, 1 point), and difficulty with 4 functional variables (bathing, 2 points; walking several blocks, 2 points; managing money, 2 points, and pushing large objects, 1 point. Scores on the risk index were strongly associated with 4-year mortality in the validation cohort, with 0 to 5 points predicting a less than 4% risk, 6 to 9 points predicting a 15% risk, 10 to 13 points predicting a 42% risk, and 14 or

Development and validation of the ORACLE score to predict risk of osteoporosis.

PubMed

Richy, Florent; Deceulaer, Fréderic; Ethgen, Olivier; Bruyère, Olivier; Reginster, Jean-Yves

2004-11-01

To develop and validate a composite index, the Osteoporosis Risk Assessment by Composite Linear Estimate (ORACLE), that includes risk factors and ultrasonometric outcomes to screen for osteoporosis. Two cohorts of postmenopausal women aged 45 years and older participated in the development (n = 407) and the validation (n = 202) of ORACLE. Their bone mineral density was determined by dual energy x-ray absorptiometry and quantitative ultrasonometry (QUS), and their historical and clinical risk factors were assessed (January to June 2003). Logistic regression analysis was used to select significant predictors of bone mineral density, whereas receiver operating characteristic (ROC) analysis was used to assess the discriminatory performance of ORACLE. The final logistic regression model retained 4 biometric or historical variables and 1 ultrasonometric outcome. The ROC areas under the curves (AUCs) for ORACLE were 84% for the prediction of osteoporosis and 78% for low bone mass. A sensitivity of 90% corresponded to a specificity of 50% for identification of women at risk of developing osteoporosis. The corresponding positive and negative predictive values were 86% and 54%, respectively, in the development cohort. In the validation cohort, the AUCs for identification of osteoporosis and low bone mass were 81% and 76% for ORACLE, 69% and 64% for QUS T score, 71% and 68% for QUS ultrasonometric bone profile index, and 76% and 75% for Osteoporosis Self-assessment Tool, respectively. ORACLE had the best discriminatory performance in identifying osteoporosis compared with the other approaches (P < .05). ORACLE exhibited the highest discriminatory properties compared with ultrasonography alone or other previously validated risk indices. It may be helpful to enhance the predictive value of QUS.

Evaluating the reliability, validity, acceptability, and practicality of SMS text messaging as a tool to collect research data: results from the Feeding Your Baby project.

PubMed

Whitford, Heather M; Donnan, Peter T; Symon, Andrew G; Kellett, Gillian; Monteith-Hodge, Ewa; Rauchhaus, Petra; Wyatt, Jeremy C

2012-01-01

To test the reliability, validity, acceptability, and practicality of short message service (SMS) messaging for collection of research data. The studies were carried out in a cohort of recently delivered women in Tayside, Scotland, UK, who were asked about their current infant feeding method and future feeding plans. Reliability was assessed by comparison of their responses to two SMS messages sent 1 day apart. Validity was assessed by comparison of their responses to text questions and the same question administered by phone 1 day later, by comparison with the same data collected from other sources, and by correlation with other related measures. Acceptability was evaluated using quantitative and qualitative questions, and practicality by analysis of a researcher log. Reliability of the factual SMS message gave perfect agreement. Reliabilities for the numerical question were reasonable, with κ between 0.76 (95% CI 0.56 to 0.96) and 0.80 (95% CI 0.59 to 1.00). Validity for data compared with that collected by phone within 24 h (κ =0.92 (95% CI 0.84 to 1.00)) and with health visitor data (κ =0.85 (95% CI 0.73 to 0.97)) was excellent. Correlation validity between the text responses and other related demographic and clinical measures was as expected. Participants found the method a convenient and acceptable way of providing data. For researchers, SMS text messaging provided an easy and functional method of gathering a large volume of data. In this sample and for these questions, SMS was a reliable and valid method for capturing research data.

Assessing the order of magnitude of outcomes in single-arm cohorts through systematic comparison with corresponding cohorts: An example from the AMOS study

PubMed Central

Hamre, Harald J; Glockmann, Anja; Tröger, Wilfried; Kienle, Gunver S; Kiene, Helmut

2008-01-01

Background When a therapy has been evaluated in the first clinical study, the outcome is often compared descriptively to outcomes in corresponding cohorts receiving other treatments. Such comparisons are often limited to selected studies, and often mix different outcomes and follow-up periods. Here we give an example of a systematic comparison to all cohorts with identical outcomes and follow-up periods. Methods The therapy to be compared (anthroposophic medicine, a complementary therapy system) had been evaluated in one single-arm cohort study: the Anthroposophic Medicine Outcomes Study (AMOS). The five largest AMOS diagnosis groups (A-cohorts: asthma, depression, low back pain, migraine, neck pain) were compared to all retrievable corresponding cohorts (C-cohorts) receiving other therapies with identical outcomes (SF-36 scales or summary measures) and identical follow-up periods (3, 6 or 12 months). Between-group differences (pre-post difference in an A-cohort minus pre-post difference in the respective C-cohort) were divided with the standard deviation (SD) of the baseline score of the A-cohort. Results A-cohorts (5 cohorts with 392 patients) were similar to C-cohorts (84 cohorts with 16,167 patients) regarding age, disease duration, baseline affection and follow-up rates. A-cohorts had ≥ 0.50 SD larger improvements than C-cohorts in 13.5% (70/517) of comparisons; improvements of the same order of magnitude (small or minimal differences: -0.49 to 0.49 SD) were found in 80.1% of comparisons; and C-cohorts had ≥ 0.50 SD larger improvements than A-cohorts in 6.4% of comparisons. Analyses stratified by diagnosis had similar results. Sensitivity analyses, restricting the comparisons to C-cohorts with similar study design (observational studies), setting (primary care) or interventions (drugs, physical therapies, mixed), or restricting comparisons to SF-36 scales with small baseline differences between A- and C-cohorts (-0.49 to 0.49 SD) also had similar results

Improved design of prodromal Alzheimer's disease trials through cohort enrichment and surrogate endpoints.

PubMed

Macklin, Eric A; Blacker, Deborah; Hyman, Bradley T; Betensky, Rebecca A

2013-01-01

Alzheimer's disease (AD) trials initiated during or before the prodrome are costly and lengthy because patients are enrolled long before clinical symptoms are apparent, when disease progression is slow. We hypothesized that design of such trials could be improved by: 1) selecting individuals at moderate near-term risk of progression to AD dementia (the current clinical standard) and 2) by using short-term surrogate endpoints that predict progression to AD dementia. We used a longitudinal cohort of older, initially non-demented, community-dwelling participants (n = 358) to derive selection criteria and surrogate endpoints and tested them in an independent national data set (n = 6,243). To identify a "mid-risk" subgroup, we applied conditional tree-based survival models to Clinical Dementia Rating (CDR) scale scores and common neuropsychological tests. In the validation cohort, a time-to-AD dementia trial applying these mid-risk selection criteria to a pool of all non-demented individuals could achieve equivalent power with 47% fewer participants than enrolling at random from that pool. We evaluated surrogate endpoints measureable over two years of follow-up based on cross-validated concordance between predictions from Cox models and observed time to AD dementia. The best performing surrogate, rate of change in CDR sum-of-boxes, did not reduce the trial duration required for equivalent power using estimates from the validation cohort, but alternative surrogates with better ability to predict time to AD dementia should be able to do so. The approach tested here might improve efficiency of prodromal AD trials using other potential measures and could be generalized to other diseases with long prodromal phases.

Prediction of psychosis across protocols and risk cohorts using automated language analysis

PubMed Central

Corcoran, Cheryl M.; Carrillo, Facundo; Fernández‐Slezak, Diego; Bedi, Gillinder; Klim, Casimir; Javitt, Daniel C.; Bearden, Carrie E.; Cecchi, Guillermo A.

2018-01-01

Language and speech are the primary source of data for psychiatrists to diagnose and treat mental disorders. In psychosis, the very structure of language can be disturbed, including semantic coherence (e.g., derailment and tangentiality) and syntactic complexity (e.g., concreteness). Subtle disturbances in language are evident in schizophrenia even prior to first psychosis onset, during prodromal stages. Using computer‐based natural language processing analyses, we previously showed that, among English‐speaking clinical (e.g., ultra) high‐risk youths, baseline reduction in semantic coherence (the flow of meaning in speech) and in syntactic complexity could predict subsequent psychosis onset with high accuracy. Herein, we aimed to cross‐validate these automated linguistic analytic methods in a second larger risk cohort, also English‐speaking, and to discriminate speech in psychosis from normal speech. We identified an automated machine‐learning speech classifier – comprising decreased semantic coherence, greater variance in that coherence, and reduced usage of possessive pronouns – that had an 83% accuracy in predicting psychosis onset (intra‐protocol), a cross‐validated accuracy of 79% of psychosis onset prediction in the original risk cohort (cross‐protocol), and a 72% accuracy in discriminating the speech of recent‐onset psychosis patients from that of healthy individuals. The classifier was highly correlated with previously identified manual linguistic predictors. Our findings support the utility and validity of automated natural language processing methods to characterize disturbances in semantics and syntax across stages of psychotic disorder. The next steps will be to apply these methods in larger risk cohorts to further test reproducibility, also in languages other than English, and identify sources of variability. This technology has the potential to improve prediction of psychosis outcome among at‐risk youths and identify

Prediction of psychosis across protocols and risk cohorts using automated language analysis.

PubMed

Corcoran, Cheryl M; Carrillo, Facundo; Fernández-Slezak, Diego; Bedi, Gillinder; Klim, Casimir; Javitt, Daniel C; Bearden, Carrie E; Cecchi, Guillermo A

2018-02-01

Language and speech are the primary source of data for psychiatrists to diagnose and treat mental disorders. In psychosis, the very structure of language can be disturbed, including semantic coherence (e.g., derailment and tangentiality) and syntactic complexity (e.g., concreteness). Subtle disturbances in language are evident in schizophrenia even prior to first psychosis onset, during prodromal stages. Using computer-based natural language processing analyses, we previously showed that, among English-speaking clinical (e.g., ultra) high-risk youths, baseline reduction in semantic coherence (the flow of meaning in speech) and in syntactic complexity could predict subsequent psychosis onset with high accuracy. Herein, we aimed to cross-validate these automated linguistic analytic methods in a second larger risk cohort, also English-speaking, and to discriminate speech in psychosis from normal speech. We identified an automated machine-learning speech classifier - comprising decreased semantic coherence, greater variance in that coherence, and reduced usage of possessive pronouns - that had an 83% accuracy in predicting psychosis onset (intra-protocol), a cross-validated accuracy of 79% of psychosis onset prediction in the original risk cohort (cross-protocol), and a 72% accuracy in discriminating the speech of recent-onset psychosis patients from that of healthy individuals. The classifier was highly correlated with previously identified manual linguistic predictors. Our findings support the utility and validity of automated natural language processing methods to characterize disturbances in semantics and syntax across stages of psychotic disorder. The next steps will be to apply these methods in larger risk cohorts to further test reproducibility, also in languages other than English, and identify sources of variability. This technology has the potential to improve prediction of psychosis outcome among at-risk youths and identify linguistic targets for remediation

Validation of WINROP for detecting retinopathy of prematurity in a North American cohort of preterm infants.

PubMed

Jung, Jennifer L; Wagner, Brandie D; McCourt, Emily A; Palestine, Alan G; Cerda, Ashlee; Cao, Jennifer H; Enzenauer, Robert W; Singh, Jasleen K; Braverman, Rebecca S; Wymore, Erica; Lynch, Anne M

2017-06-01

WINROP (weight, insulin-like growth factor 1, neonatal, retinopathy of prematurity) is a web-based retinopathy of prematurity (ROP) risk algorithm that uses postnatal weight gain as a surrogate of insulin-like growth factor-1 (IGF-1) to predict the risk of severe ROP in premature infants. The purpose of this study was to validate the web-based algorithm WINROP in detecting severe (type 1 or type 2) ROP in a North American cohort of infants. The records of consecutive infants who underwent ROP examinations between 2008 and 2011 were reviewed retrospectively. Infants were classified into categories of "alarm" (at risk for developing severe ROP) and "no alarm" (minimal risk for severe ROP). A total of 483 were included. Alarm occurred in 241 neonates (50%), with the median time from birth to alarm of 2 weeks. WINROP had a sensitivity of 81.8% (95% CI, 67.3%-91.8%) and specificity of 53.3% (95% CI, 48.5%-58.0%) for identifying infants with severe ROP. Eight of the 44 infants with severe ROP were not detected (5 with type 1 and 3 with type 2). Of these 8 infants, 7 (88%) had birth weight in excess of the 70 th pecentile. With additional weight data entry, sensitivity of WINROP rose to 88.6%. Very preterm infants (gestational age of ≤27 weeks) with relatively high birth weight for gestational age may not be detected by WINROP as high risk for developing severe ROP. Copyright © 2017 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

The Hokkaido Birth Cohort Study on Environment and Children's Health: cohort profile-updated 2017.

PubMed

Kishi, Reiko; Araki, Atsuko; Minatoya, Machiko; Hanaoka, Tomoyuki; Miyashita, Chihiro; Itoh, Sachiko; Kobayashi, Sumitaka; Ait Bamai, Yu; Yamazaki, Keiko; Miura, Ryu; Tamura, Naomi; Ito, Kumiko; Goudarzi, Houman

2017-05-18

The Hokkaido Study on Environment and Children's Health is an ongoing study consisting of two birth cohorts of different population sizes: the Sapporo cohort and the Hokkaido cohort. Our primary study goals are (1) to examine the effects of low-level environmental chemical exposures on birth outcomes, including birth defects and growth retardation; (2) to follow the development of allergies, infectious diseases, and neurobehavioral developmental disorders and perform a longitudinal observation of child development; (3) to identify high-risk groups based on genetic susceptibility to environmental chemicals; and (4) to identify the additive effects of various chemicals, including tobacco smoking. The purpose of this report is to update the progress of the Hokkaido Study, to summarize the recent results, and to suggest future directions. In particular, this report provides the basic characteristics of the cohort populations, discusses the population remaining in the cohorts and those who were lost to follow-up at birth, and introduces the newly added follow-up studies and case-cohort study design. In the Sapporo cohort of 514 enrolled pregnant women, various specimens, including maternal and cord blood, maternal hair, and breast milk, were collected for the assessment of exposures to dioxins, polychlorinated biphenyls, organochlorine pesticides, perfluoroalkyl substances, phthalates, bisphenol A, and methylmercury. As follow-ups, face-to-face neurobehavioral developmental tests were conducted at several different ages. In the Hokkaido cohort of 20,926 enrolled pregnant women, the prevalence of complicated pregnancies and birth outcomes, such as miscarriage, stillbirth, low birth weight, preterm birth, and small for gestational age were examined. The levels of exposure to environmental chemicals were relatively low in these study populations compared to those reported previously. We also studied environmental chemical exposure in association with health outcomes

Psychometric properties of the 30-m walking test in patients with degenerative cervical myelopathy: results from two prospective multicenter cohort studies.

PubMed

Bohm, Parker E; Fehlings, Michael G; Kopjar, Branko; Tetreault, Lindsay A; Vaccaro, Alexander R; Anderson, Karen K; Arnold, Paul M

2017-02-01

The timed 30-m walking test (30MWT) is used in clinical practice and in research to objectively quantify gait impairment. The psychometric properties of 30MWT have not yet been rigorously evaluated. This study aimed to determine test-retest reliability, divergent and convergent validity, and responsiveness to change of the 30MWT in patients with degenerative cervical myelopathy (DCM). A retrospective observational study was carried out. The sample consisted of patients with symptomatic DCM enrolled in the AOSpine North America or AOSpine International cervical spondylotic myelopathy studies at 26 sites. Modified Japanese Orthopaedic Association scale (mJOA), Nurick scale, 30MWT, Neck Disability Index (NDI), and Short-Form-36 (SF-36v2) physical component score (PCS) and mental component score (MCS) were the outcome measures. Data from two prospective multicenter cohort myelopathy studies were merged. Each patient was evaluated at baseline and 6 months postoperatively. Of 757 total patients, 682 (90.09%) attempted to perform the 30MWT at baseline. Of these 682 patients, 602 (88.12%) performed the 30MWT at baseline. One patient was excluded, leaving601 in the analysis. At baseline, 81 of 682 (11.88%) patients were unable to perform the test, and their mJOA, NDI, and SF-36v2 PCS scores were lower compared with those who performed the test at baseline. In patients who performed the 30MWT at baseline, there was very high correlation among the three baseline 30MWT measurements (r=0.9569-0.9919). The 30MWT demonstrated good convergent and divergent validity. It was moderately correlated with the Nurick (r=0.4932), mJOA (r=-0.4424), and SF-36v2 PCS (r=-0.3537) (convergent validity) and poorly correlated with the NDI (r=0.2107) and SF-36v2 MCS (r=-0.1984) (divergent validity). Overall, the 30MWT was not responsive to change (standardized response mean [SRM]=0.30). However, for patients who had a baseline time above the median value of 29 seconds, the SRM was 0.45. The 30MWT

Local Validation of Global Estimates of Biosphere Properties: Synthesis of Scaling Methods and Results Across Several Major Biomes

NASA Technical Reports Server (NTRS)

Cohen, Warren B.; Wessman, Carol A.; Aber, John D.; VanderCaslte, John R.; Running, Steven W.

1998-01-01

To assist in validating future MODIS land cover, LAI, IPAR, and NPP products, this project conducted a series of prototyping exercises that resulted in enhanced understanding of the issues regarding such validation. As a result, we have several papers to appear as a special issue of Remote Sensing of Environment in 1999. Also, we have been successful at obtaining a follow-on grant to pursue actual validation of these products over the next several years. This document consists of a delivery letter, including a listing of published papers.

A prospective cohort study to refine and validate the Panic Screening Score for identifying panic attacks associated with unexplained chest pain in the emergency department

PubMed Central

Foldes-Busque, Guillaume; Denis, Isabelle; Poitras, Julien; Fleet, Richard P; Archambault, Patrick; Dionne, Clermont E

2013-01-01

Introduction Panic-like anxiety (panic attacks with or without panic disorder), a highly treatable condition, is the most prevalent condition associated with unexplained chest pain in the emergency department. Panic-like anxiety may be responsible for a significant portion of the negative consequences of unexplained chest pain, such as functional limitations and chronicity. However, more than 92% of panic-like anxiety cases remain undiagnosed at the time of discharge from the emergency department. The 4-item Panic Screening Score (PSS) questionnaire was derived in order to increase the identification of panic-like anxiety in emergency department patients with unexplained chest pain. Methods and analysis The goals of this prospective cohort study were to (1) refine the PSS; (2) validate the revised version of the PSS; (3) measure the reliability of the revised version of the PSS and (4) assess the acceptability of the instrument among emergency physicians. Eligible and consenting patients will be administered the PSS in a large emergency department. Patients will be contacted by phone for administration of the criterion standard for panic attacks as well as by a standardised interview to collect information for other predictors of panic attacks. Multivariate analysis will be used to refine the PSS. The new version will be prospectively validated in an independent sample and inter-rater agreement will be assessed in 10% of cases. The screening instrument acceptability will be assessed with the Ottawa Acceptability of Decision Rules Instrument. Ethics and dissemination This study protocol has been reviewed and approved by the Alphonse-Desjardins research ethics committee. The results of the study will be presented in scientific conferences and published in peer-reviewed scientific journals. Further dissemination via workshops and a dedicated website is planned. PMID:24163208

Predicting return to work after low back injury using the Psychosocial Risk for Occupational Disability Instrument: a validation study.

PubMed

Schultz, I Z; Crook, J; Berkowitz, J; Milner, R; Meloche, G R

2005-09-01

This paper reports on the predictive validity of a Psychosocial Risk for Occupational Disability Scale in the workers' compensation environment using a paper and pencil version of a previously validated multimethod instrument on a new, subacute sample of workers with low back pain. A cohort longitudinal study design with a randomly selected cohort off work for 4-6 weeks was applied. The questionnaire was completed by 111 eligible workers at 4-6 weeks following injury. Return to work status data at three months was obtained from 100 workers. Sixty-four workers had returned to work (RTW) and 36 had not (NRTW). Stepwise backward elimination resulted in a model with these predictors: Expectations of Recovery, SF-36 Vitality, SF-36 Mental Health, and Waddell Symptoms. The correct classification of RTW/NRTW was 79%, with sensitivity (NRTW) of 61% and specificity (RTW) of 89%. The area under the ROC curve was 84%. New evidence for predictive validity for the Psychosocial Risk-for-Disability Instrument was provided. The instrument can be useful and practical for prediction of return to work outcomes in the subacute stage after low back injury in the workers' compensation context.

Authoritarian parenting attitudes as a risk for conduct problems Results from a British national cohort study.

PubMed

Thompson, Anne; Hollis, Chris; Dagger, David Richards

2003-04-01

This study examines the associations, and possible causal relationship, between mothers' authoritarian attitudes to discipline and child behaviour using cross-sectional and prospective data from a large population sample surveyed in the 1970 British Cohort Study. Results show a clear linear relationship between the degree of maternal approval of authoritarian child-rearing attitudes and the rates of conduct problems at age 5 and age 10. This association is independent of the confounding effects of socio-economic status and maternal psychological distress. Maternal authoritarian attitudes independently predicted the development of conduct problems 5 years later at age 10. The results of this longitudinal study suggest that authoritarian parenting attitudes expressed by mothers may be of significance in the development of conduct problems.

Risk for borderline ovarian tumours after exposure to fertility drugs: results of a population-based cohort study.

PubMed

Bjørnholt, Sarah Marie; Kjaer, Susanne Krüger; Nielsen, Thor Schütt Svane; Jensen, Allan

2015-01-01

Do fertility drugs increase the risk for borderline ovarian tumours, overall and according to histological subtype? The use of any fertility drug did not increase the overall risk for borderline ovarian tumours, but an increased risk for serous borderline ovarian tumours was observed after the use of progesterone. Many epidemiological studies have addressed the connection between fertility drugs use and risk for ovarian cancer; most have found no strong association. Fewer studies have assessed the association between use of fertility drugs and risk for borderline ovarian tumours, and the results are inconsistent. A retrospective case-cohort study was designed with data from a cohort of 96 545 Danish women with fertility problems referred to all Danish fertility clinics in the period 1963-2006. All women were followed for first occurrence of a borderline ovarian tumour from the initial date of infertility evaluation until a date of migration, date of death or 31 December 2006, whichever occurred first. The median length of follow-up was 11.3 years. Included in the analyses were 142 women with borderline ovarian tumours (cases) and 1328 randomly selected sub-cohort members identified in the cohort during the follow-up through 2006. Cases were identified by linkage to the Danish Cancer Register and the Danish Register of Pathology by use of personal identification numbers. To obtain information on use of fertility drugs, hospital files and medical records of infertility-associated visits to all Danish fertility clinics were collected and supplemented with information from the Danish IVF register. We used case-cohort techniques to calculate rate ratios (RRs) and corresponding 95% confidence intervals (CIs) for borderline ovarian tumours, overall and according to histological subtype, associated with the use of any fertility drug or five specific groups of fertility drugs: clomiphene citrate, gonadotrophins (human menopausal gonadotrophins and follicle

Validity of proposed DSM-5 diagnostic criteria for nicotine use disorder: results from 734 Israeli lifetime smokers

PubMed Central

Shmulewitz, D.; Wall, M.M.; Aharonovich, E.; Spivak, B.; Weizman, A.; Frisch, A.; Grant, B. F.; Hasin, D.

2013-01-01

Background The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) proposes aligning nicotine use disorder (NUD) criteria with those for other substances, by including the current DSM fourth edition (DSM-IV) nicotine dependence (ND) criteria, three abuse criteria (neglect roles, hazardous use, interpersonal problems) and craving. Although NUD criteria indicate one latent trait, evidence is lacking on: (1) validity of each criterion; (2) validity of the criteria as a set; (3) comparative validity between DSM-5 NUD and DSM-IV ND criterion sets; and (4) NUD prevalence. Method Nicotine criteria (DSM-IV ND, abuse and craving) and external validators (e.g. smoking soon after awakening, number of cigarettes per day) were assessed with a structured interview in 734 lifetime smokers from an Israeli household sample. Regression analysis evaluated the association between validators and each criterion. Receiver operating characteristic analysis assessed the association of the validators with the DSM-5 NUD set (number of criteria endorsed) and tested whether DSM-5 or DSM-IV provided the most discriminating criterion set. Changes in prevalence were examined. Results Each DSM-5 NUD criterion was significantly associated with the validators, with strength of associations similar across the criteria. As a set, DSM-5 criteria were significantly associated with the validators, were significantly more discriminating than DSM-IV ND criteria, and led to increased prevalence of binary NUD (two or more criteria) over ND. Conclusions All findings address previous concerns about the DSM-IV nicotine diagnosis and its criteria and support the proposed changes for DSM-5 NUD, which should result in improved diagnosis of nicotine disorders. PMID:23312475

Pharmacokinetic modeling of gentamicin in treatment of infective endocarditis: Model development and validation of existing models.

PubMed

Gomes, Anna; van der Wijk, Lars; Proost, Johannes H; Sinha, Bhanu; Touw, Daan J

2017-01-01

Gentamicin shows large variations in half-life and volume of distribution (Vd) within and between individuals. Thus, monitoring and accurately predicting serum levels are required to optimize effectiveness and minimize toxicity. Currently, two population pharmacokinetic models are applied for predicting gentamicin doses in adults. For endocarditis patients the optimal model is unknown. We aimed at: 1) creating an optimal model for endocarditis patients; and 2) assessing whether the endocarditis and existing models can accurately predict serum levels. We performed a retrospective observational two-cohort study: one cohort to parameterize the endocarditis model by iterative two-stage Bayesian analysis, and a second cohort to validate and compare all three models. The Akaike Information Criterion and the weighted sum of squares of the residuals divided by the degrees of freedom were used to select the endocarditis model. Median Prediction Error (MDPE) and Median Absolute Prediction Error (MDAPE) were used to test all models with the validation dataset. We built the endocarditis model based on data from the modeling cohort (65 patients) with a fixed 0.277 L/h/70kg metabolic clearance, 0.698 (±0.358) renal clearance as fraction of creatinine clearance, and Vd 0.312 (±0.076) L/kg corrected lean body mass. External validation with data from 14 validation cohort patients showed a similar predictive power of the endocarditis model (MDPE -1.77%, MDAPE 4.68%) as compared to the intensive-care (MDPE -1.33%, MDAPE 4.37%) and standard (MDPE -0.90%, MDAPE 4.82%) models. All models acceptably predicted pharmacokinetic parameters for gentamicin in endocarditis patients. However, these patients appear to have an increased Vd, similar to intensive care patients. Vd mainly determines the height of peak serum levels, which in turn correlate with bactericidal activity. In order to maintain simplicity, we advise to use the existing intensive-care model in clinical practice to avoid

Pharmacokinetic modeling of gentamicin in treatment of infective endocarditis: Model development and validation of existing models

PubMed Central

van der Wijk, Lars; Proost, Johannes H.; Sinha, Bhanu; Touw, Daan J.

2017-01-01

Gentamicin shows large variations in half-life and volume of distribution (Vd) within and between individuals. Thus, monitoring and accurately predicting serum levels are required to optimize effectiveness and minimize toxicity. Currently, two population pharmacokinetic models are applied for predicting gentamicin doses in adults. For endocarditis patients the optimal model is unknown. We aimed at: 1) creating an optimal model for endocarditis patients; and 2) assessing whether the endocarditis and existing models can accurately predict serum levels. We performed a retrospective observational two-cohort study: one cohort to parameterize the endocarditis model by iterative two-stage Bayesian analysis, and a second cohort to validate and compare all three models. The Akaike Information Criterion and the weighted sum of squares of the residuals divided by the degrees of freedom were used to select the endocarditis model. Median Prediction Error (MDPE) and Median Absolute Prediction Error (MDAPE) were used to test all models with the validation dataset. We built the endocarditis model based on data from the modeling cohort (65 patients) with a fixed 0.277 L/h/70kg metabolic clearance, 0.698 (±0.358) renal clearance as fraction of creatinine clearance, and Vd 0.312 (±0.076) L/kg corrected lean body mass. External validation with data from 14 validation cohort patients showed a similar predictive power of the endocarditis model (MDPE -1.77%, MDAPE 4.68%) as compared to the intensive-care (MDPE -1.33%, MDAPE 4.37%) and standard (MDPE -0.90%, MDAPE 4.82%) models. All models acceptably predicted pharmacokinetic parameters for gentamicin in endocarditis patients. However, these patients appear to have an increased Vd, similar to intensive care patients. Vd mainly determines the height of peak serum levels, which in turn correlate with bactericidal activity. In order to maintain simplicity, we advise to use the existing intensive-care model in clinical practice to avoid

Tinned Fruit Consumption and Mortality in Three Prospective Cohorts

PubMed Central

Aasheim, Erlend T.; Sharp, Stephen J.; Appleby, Paul N.; Shipley, Martin J.; Lentjes, Marleen A. H.; Khaw, Kay-Tee; Brunner, Eric; Key, Tim J.; Wareham, Nicholas J.

2015-01-01

Dietary recommendations to promote health include fresh, frozen and tinned fruit, but few studies have examined the health benefits of tinned fruit. We therefore studied the association between tinned fruit consumption and mortality. We followed up participants from three prospective cohorts in the United Kingdom: 22,421 participants from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk cohort (1993–2012), 52,625 participants from the EPIC-Oxford cohort (1993–2012), and 7440 participants from the Whitehall II cohort (1991–2012), all reporting no history of heart attack, stroke, or cancer when entering these studies. We estimated the association between frequency of tinned fruit consumption and all cause mortality (primary outcome measure) using Cox regression models within each cohort, and pooled hazard ratios across cohorts using random-effects meta-analysis. Tinned fruit consumption was assessed with validated food frequency questionnaires including specific questions about tinned fruit. During 1,305,330 person years of follow-up, 8857 deaths occurred. After adjustment for lifestyle factors and risk markers the pooled hazard ratios (95% confidence interval) of all cause mortality compared with the reference group of tinned fruit consumption less often than one serving per month were: 1.05 (0.99, 1.12) for one to three servings per month, 1.10 (1.03, 1.18) for one serving per week, and 1.13 (1.04, 1.23) for two or more servings per week. Analysis of cause-specific mortality showed that tinned fruit consumption was associated with mortality from cardiovascular causes and from non-cardiovascular, non-cancer causes. In a pooled analysis of three prospective cohorts from the United Kingdom self-reported tinned fruit consumption in the 1990s was weakly but positively associated with mortality during long-term follow-up. These findings raise questions about the evidence underlying dietary recommendations to promote tinned fruit

Cause of death in patients with poststroke epilepsy: Results from a nationwide cohort study.

PubMed

Hansen, Julia; Åsberg, Signild; Kumlien, Eva; Zelano, Johan

2017-01-01

The risk of death is increased for persons with epilepsy. The literature on causes of death in epilepsy is based mainly on cohorts with epilepsy of mixed aetiologies. For clinical purposes and improved understanding of mortality in different epilepsies, more information is needed on mortality in epilepsies of specific causes. In poststroke epilepsy (PSE), seizures occur in a setting of vascular disease and high mortality rates. The extent to which epilepsy contributes to mortality in this patient group is poorly understood. We therefore aimed to describe causes of death (COD) in PSE on a national scale. A previously identified cohort of 7740 patients with epilepsy or seizures after a stroke in 2005-2010 was investigated. A total of 4167 deaths occurred before the end of 2014. The standardized mortality ratio for the study cohort was 3.56 (95% CI: 3.45-3.67). The main underlying causes of death were disorders of the circulatory system (60%) followed by neoplasms (12%). Diseases of the nervous system were the sixth leading underlying COD (3%), and epilepsy or status epilepticus was considered the underlying COD in approximately a similar proportion of cases as neurodegenerative disorders (0.9% and 1.1%, respectively). Epilepsy was considered a contributing COD in 14% of cases. Our findings highlight the importance of optimal management of vascular morbidity in patients with PSE. The large proportion of patients with epilepsy as a contributing COD indicate the need of high ambitions also regarding the management of seizures in patients with PSE.

V-SUIT Model Validation Using PLSS 1.0 Test Results

NASA Technical Reports Server (NTRS)

Olthoff, Claas

2015-01-01

The dynamic portable life support system (PLSS) simulation software Virtual Space Suit (V-SUIT) has been under development at the Technische Universitat Munchen since 2011 as a spin-off from the Virtual Habitat (V-HAB) project. The MATLAB(trademark)-based V-SUIT simulates space suit portable life support systems and their interaction with a detailed and also dynamic human model, as well as the dynamic external environment of a space suit moving on a planetary surface. To demonstrate the feasibility of a large, system level simulation like V-SUIT, a model of NASA's PLSS 1.0 prototype was created. This prototype was run through an extensive series of tests in 2011. Since the test setup was heavily instrumented, it produced a wealth of data making it ideal for model validation. The implemented model includes all components of the PLSS in both the ventilation and thermal loops. The major components are modeled in greater detail, while smaller and ancillary components are low fidelity black box models. The major components include the Rapid Cycle Amine (RCA) CO2 removal system, the Primary and Secondary Oxygen Assembly (POS/SOA), the Pressure Garment System Volume Simulator (PGSVS), the Human Metabolic Simulator (HMS), the heat exchanger between the ventilation and thermal loops, the Space Suit Water Membrane Evaporator (SWME) and finally the Liquid Cooling Garment Simulator (LCGS). Using the created model, dynamic simulations were performed using same test points also used during PLSS 1.0 testing. The results of the simulation were then compared to the test data with special focus on absolute values during the steady state phases and dynamic behavior during the transition between test points. Quantified simulation results are presented that demonstrate which areas of the V-SUIT model are in need of further refinement and those that are sufficiently close to the test results. Finally, lessons learned from the modelling and validation process are given in combination

Reproducibility and validity of the Shanghai Women's Health Study physical activity questionnaire.

PubMed

Matthews, Charles E; Shu, Xiao-Ou; Yang, Gong; Jin, Fan; Ainsworth, Barbara E; Liu, Dake; Gao, Yu-Tang; Zheng, Wei

2003-12-01

In this investigation, the authors evaluated the reproducibility and validity of the Shanghai Women's Health Study (SWHS) physical activity questionnaire (PAQ), which was administered in a cohort study of approximately 75,000 Chinese women aged 40-70 years. Reproducibility (2-year test-retest) was evaluated using kappa statistics and intraclass correlation coefficients (ICCs). Validity was evaluated by comparing Spearman correlations (r) for the SWHS PAQ with two criterion measures administered over a period of 12 months: four 7-day physical activity logs and up to 28 7-day PAQs. Women were recruited from the SWHS cohort (n = 200). Results indicated that the reproducibility of adolescent and adult exercise participation (kappa = 0.85 and kappa = 0.64, respectively) and years of adolescent exercise and adult exercise energy expenditure (ICC = 0.83 and ICC = 0.70, respectively) was reasonable. Reproducibility values for adult lifestyle activities were lower (ICC = 0.14-0.54). Significant correlations between the PAQ and criterion measures of adult exercise were observed for the first PAQ administration (physical activity log, r = 0.50; 7-day PAQ, r = 0.62) and the second PAQ administration (physical activity log, r = 0.74; 7-day PAQ, r = 0.80). Significant correlations between PAQ lifestyle activities and the 7-day PAQ were also noted (r = 0.33-0.88). These data indicate that the SWHS PAQ is a reproducible and valid measure of exercise behaviors and that it demonstrates utility in stratifying women by levels of important lifestyle activities (e.g., housework, walking, cycling).

Lessons Learned From Methodological Validation Research in E-Epidemiology.

PubMed

Kesse-Guyot, Emmanuelle; Assmann, Karen; Andreeva, Valentina; Castetbon, Katia; Méjean, Caroline; Touvier, Mathilde; Salanave, Benoît; Deschamps, Valérie; Péneau, Sandrine; Fezeu, Léopold; Julia, Chantal; Allès, Benjamin; Galan, Pilar; Hercberg, Serge

2016-10-18

Traditional epidemiological research methods exhibit limitations leading to high logistics, human, and financial burden. The continued development of innovative digital tools has the potential to overcome many of the existing methodological issues. Nonetheless, Web-based studies remain relatively uncommon, partly due to persistent concerns about validity and generalizability. The objective of this viewpoint is to summarize findings from methodological studies carried out in the NutriNet-Santé study, a French Web-based cohort study. On the basis of the previous findings from the NutriNet-Santé e-cohort (>150,000 participants are currently included), we synthesized e-epidemiological knowledge on sample representativeness, advantageous recruitment strategies, and data quality. Overall, the reported findings support the usefulness of Web-based studies in overcoming common methodological deficiencies in epidemiological research, in particular with regard to data quality (eg, the concordance for body mass index [BMI] classification was 93%), reduced social desirability bias, and access to a wide range of participant profiles, including the hard-to-reach subgroups such as young (12.30% [15,118/122,912], <25 years) and old people (6.60% [8112/122,912], ≥65 years), unemployed or homemaker (12.60% [15,487/122,912]), and low educated (38.50% [47,312/122,912]) people. However, some selection bias remained (78.00% (95,871/122,912) of the participants were women, and 61.50% (75,590/122,912) had postsecondary education), which is an inherent aspect of cohort study inclusion; other specific types of bias may also have occurred. Given the rapidly growing access to the Internet across social strata, the recruitment of participants with diverse socioeconomic profiles and health risk exposures was highly feasible. Continued efforts concerning the identification of specific biases in e-cohorts and the collection of comprehensive and valid data are still needed. This summary of

Derivation and validation of a novel risk score for safe discharge after acute lower gastrointestinal bleeding: a modelling study.

PubMed

Oakland, Kathryn; Jairath, Vipul; Uberoi, Raman; Guy, Richard; Ayaru, Lakshmana; Mortensen, Neil; Murphy, Mike F; Collins, Gary S

2017-09-01

Acute lower gastrointestinal bleeding is a common reason for emergency hospital admission, and identification of patients at low risk of harm, who are therefore suitable for outpatient investigation, is a clinical and research priority. We aimed to develop and externally validate a simple risk score to identify patients with lower gastrointestinal bleeding who could safely avoid hospital admission. We undertook model development with data from the National Comparative Audit of Lower Gastrointestinal Bleeding from 143 hospitals in the UK in 2015. Multivariable logistic regression modelling was used to identify predictors of safe discharge, defined as the absence of rebleeding, blood transfusion, therapeutic intervention, 28 day readmission, or death. The model was converted into a simplified risk scoring system and was externally validated in 288 patients admitted with lower gastrointestinal bleeding (184 safely discharged) from two UK hospitals (Charing Cross Hospital, London, and Hammersmith Hospital, London) that had not contributed data to the development cohort. We calculated C statistics for the new model and did a comparative assessment with six previously developed risk scores. Of 2336 prospectively identified admissions in the development cohort, 1599 (68%) were safely discharged. Age, sex, previous admission for lower gastrointestinal bleeding, rectal examination findings, heart rate, systolic blood pressure, and haemoglobin concentration strongly discriminated safe discharge in the development cohort (C statistic 0·84, 95% CI 0·82-0·86) and in the validation cohort (0·79, 0·73-0·84). Calibration plots showed the new risk score to have good calibration in the validation cohort. The score was better than the Rockall, Blatchford, Strate, BLEED, AIMS65, and NOBLADS scores in predicting safe discharge. A score of 8 or less predicts a 95% probability of safe discharge. We developed and validated a novel clinical prediction model with good discriminative

The fecal hemoglobin concentration, age and sex test score: Development and external validation of a simple prediction tool for colorectal cancer detection in symptomatic patients.

PubMed

Cubiella, Joaquín; Digby, Jayne; Rodríguez-Alonso, Lorena; Vega, Pablo; Salve, María; Díaz-Ondina, Marta; Strachan, Judith A; Mowat, Craig; McDonald, Paula J; Carey, Francis A; Godber, Ian M; Younes, Hakim Ben; Rodriguez-Moranta, Francisco; Quintero, Enrique; Álvarez-Sánchez, Victoria; Fernández-Bañares, Fernando; Boadas, Jaume; Campo, Rafel; Bujanda, Luis; Garayoa, Ana; Ferrandez, Ángel; Piñol, Virginia; Rodríguez-Alcalde, Daniel; Guardiola, Jordi; Steele, Robert J C; Fraser, Callum G