BackgroundDropouts and missing data are nearly-ubiquitous in obesity randomized controlled trails, threatening validity and generalizability of conclusions. Herein, we meta-analytically evaluate the extent of missing data, the frequency with which various analytic methods are employed to accommodate dropouts, and the performance of multiple statistical methods.Methodology/Principal FindingsWe searched PubMed and Cochrane databases (2000–2006) for articles published in English and manually searched bibliographic references. Articles of pharmaceutical randomized controlled trials with weight loss or weight gain prevention as major endpoints were included. Two authors independently reviewed each publication for inclusion. 121 articles met the inclusion criteria. Two authors independently extracted treatment, sample size, drop-out rates, study duration, and statistical method used to handle missing data from all articles and resolved disagreements by consensus. In the meta-analysis, drop-out rates were substantial with the survival (non-dropout) rates being approximated by an exponential decay curve (e−λt) where λ was estimated to be .0088 (95% bootstrap confidence interval: .0076 to .0100) and t represents time in weeks. The estimated drop-out rate at 1 year was 37%. Most studies used last observation carried forward as the primary analytic method to handle missing data. We also obtained 12 raw obesity randomized controlled trial datasets for empirical analyses. Analyses of raw randomized controlled trial data suggested that both mixed models and multiple imputation performed well, but that multiple imputation may be more robust when missing data are extensive.Conclusion/SignificanceOur analysis offers an equation for predictions of dropout rates useful for future study planning. Our raw data analyses suggests that multiple imputation is better than other methods for handling missing data in obesity randomized controlled trials, followed closely by mixed models. We suggest these methods supplant last observation carried forward as the primary method of analysis.

In this study, high fitness was a stronger predictor of cancer mortality in men, whereas high BMI was a stronger predictor of cancer mortality in women.

Results:The relationship between BMI and WC as characterized by the slope of the linear regression of WC on BMI does not seem to be changing significantly over time. A small (range, 0.08 to 0.27 cm/yr) increase in WC over time was observed. Discussion: The implications of these findings for public health and for understanding any extant changes in the BMI-mortality rate relationship remain to be elucidated.

OBEJECTIVE:To examine the relative size of the effects of fitness and fatness on mortality in Russian men, and to make comparison to US men. DESIGN: Prospective closed cohort. SUBJECTS: 1359 Russian men and 1716 US men aged 40-59 y at baseline (1972)(1973)(1974)(1975)(1976)(1977) who were enrolled in the Lipids Research Clinics Study. MEASUREMENTS: Fitness was assessed using a treadmill test and fatness was assessed as body mass index (BMI) calculated from measured height and weight. Hazard ratios were calculated using proportional hazard models that included covariates for age, education, smoking, alcohol intake and dietary keys score. All-cause and cardiovascular disease (CVD) mortality were assessed through 1995. RESULTS: In Russian men, fitness was associated with all-cause and CVD mortality, but fatness was not. For mortality from all causes, compared to the fit-not fat, the adjusted hazard ratios were 0.87 (95% CI: 0.55, 1.37) among the fit-fat, 1.86 (95% CI: 1.31, 2.62) among the unfit-not fat and 1.68 (95% CI: 1.06, 2.68) among the unfit-fat. Among US men, the same hazard ratios were 1.40 (95% CI: 1.07, 1.83), 1.41 (95% CI: 1.12, 1.77) and 1.54 (95% CI: 1.24, 2.06), respectively. There were no statistically significant interactions between fitness and fatness in either group of men for all-cause or CVD mortality. CONCLUSION: The effects of fitness on mortality may be more robust across populations than are the effects of fatness.

Background Epstein-Barr virus (EBV) is an important human pathogen; it infects >90% people globally and is linked to infectious mononucleosis and several types of cancer. Vaccines against EBV are in development. In this study we present the first systematic review of the literature on risk factors for EBV infection, and discuss how they differ between settings, in order to improve our understanding of EBV epidemiology and aid the design of effective vaccination strategies.Methods MEDLINE, Embase, and Web of Science were searched on 6 th March 2017 for observational studies of risk factors for EBV infection. Studies were excluded if they were published before 2008 to ensure relevance to the modern day, given the importance of influencing future vaccination policies. There were no language restrictions. After title, abstract and full text screening, followed by checking the reference lists of included studies to identify further studies, data were extracted into standardised spreadsheets and quality assessed. A narrative synthesis was undertaken.Results Seventy-seven papers met our inclusion criteria, including data from 31 countries. There was consistent evidence that EBV seroprevalence was associated with age, increasing throughout childhood and adolescence and remaining constant thereafter. EBV was generally acquired at younger ages in Asia than Europe/North America. There was also compelling evidence for an association between cytomegalovirus infection and EBV. Additional factors associated with EBV seroprevalence, albeit with less consistent evidence, included ethnicity, socioeconomic status, other chronic viral infections, and genetic variants of HLA and immune response genes. ConclusionsOur study is the first systematic review to draw together the global literature on the risk factors for EBV infection and includes an evaluation of the quality of the published evidence. Across the literature, the factors examined are diverse. In Asia, early vaccination of infants would be required to prevent EBV infection. In contrast, in Western countries a vaccine could be deployed later, particularly if it has only a short duration of protection and the intention was to protect against infectious mononucleosis. There is a lack of high-quality data on the prevalence and age of EBV infection outside of Europe, North America and South-East Asia, which are essential for informing effective vaccination policies in these settings.

Background-Numerous public health organizations have adopted national physical activity recommendations. Despite these recommendations, over half of the US population does not meet the minimum recommendation for physical activity, with large variations across individual US states.

Background: Quality of reporting (QR) in industry-funded research is a concern of the scientific community. Greater scrutiny of industry-sponsored research reporting has been suggested, although differences in QR by sponsorship type have not been evaluated in weight loss interventions. Objective: To evaluate the association of funding source and QR of long-term obesity randomized clinical trials (RCT). Methods: We analysed papers that reported long-term weight loss trials. Articles were obtained through searches of Medline, HealthStar, and the Cochrane Controlled Trials Register between the years 1966 and 2003. QR scores were determined for each study based upon expanded criteria from the Consolidated Standards for Reporting Trials (CONSORT) checklist for a maximum score of 44 points. Studies were coded by category of industry support (0 ¼ no industry support, 1 ¼ industry support, 2 ¼ in kind contribution from industry and 3 ¼ duality of interest reported). Individual CONSORT reporting criteria were tabulated by funding type. An independent samples t-test compared the differences in QR scores by funding source and the Wilcox-MannWhitney test and generalised estimating equations (GEE) were used for sensitivity analyses. Results: Of the 63 RCTs evaluated, 67% were industry-supported trials. Industry funding was associated with higher QR score in long-term weight loss trials compared with nonindustry-funded studies (mean QR (s.d.): industry ¼ 27.9 (4.1), nonindustry ¼ 23.4 (4.1); Po0.0005). The Wilcox-Mann-Whitney test confirmed this result (Po0.0005). Controlling for the year of publication and whether the paper was published before the CONSORT statement was released in the GEE regression analysis, the direction and magnitude of effect were similar and statistically significant (P ¼ 0.035). Of the individual criteria that prior research has associated with biases, industry funding was associated with greater reporting of intent-to-treat analysis (P ¼ 0.0158), but was not different from nonindustry studies in reporting of treatment allocation and blinding. Conclusion: Our findings suggest that the efforts to improve reporting quality be directed to all obesity RCTs, irrespective of funding source.

Research has linked neighborhood socioeconomic status to differential dietary quality among adults. However, the relationship between neighborhoods and children’s diet remains understudied. The aim of the research was to examine if neighborhood disadvantage (e.g. socioeconomic status, social and physical disorder) affected dietary quality among children. Data for this cross-sectional study were gathered between June 2005 and December 2008. Research participants included 182 children aged 7 to 12 years who were of Hispanic (26%), European (28%) and African American (45%) descent. Dietary intake was gathered via two 24 hour recalls and analyzed using the Nutrition Data System for Research. Descriptive statistics and ANOVA’s were conducted to determine if there were significant differences in dietary intakes by quartile grouping of neighborhood disadvantage. Multivariate linear regression analyses were used to determine if neighborhood disadvantage (as a continuous measure) was associated with dietary quality. Overall, there were no significant differences in total caloric intake, however, children in disadvantaged neighborhoods consumed a greater percentage of calories from fat (P =.039), trans fat (P =.018), and had a higher sodium intake (P=.01). The results suggest that neighborhood factors may contribute to dietary quality among children. Future interventions should assess mechanisms to improve the availability of healthy foods while taking into account neighborhood level conditions.