Abstract available on the publisher's website.

Background: Food allergy affects an estimated 8% of children and 3% of adults in the United States. Food‐allergic individuals increasingly use the web for medical information. We sought to determine the educational quality of food allergy YouTube videos. Methods: We performed a YouTube search using keywords “food allergy” and “food allergies”. The 300 most viewed videos were included and analyzed for characteristics, source, and content. Source was further classified as healthcare provider, alternative medicine provider, patient, company, media, and professional society. A scoring system (FA‐DQS) was created to evaluate quality (−10 to +34 points). Negative points were assigned for misleading information. Eight reviewers scored each video independently. Results: Three hundred videos were analyzed, with a median of 6351.50 views, 19 likes, and 1 dislike. More video presenters were female (54.3%). The most common type of video source was alternative medicine provider (26.3%). Alternative treatments included the following: water fast, juicing, Ayurveda, apple cider, yoga, visualization, and sea moss. Controversial diagnostics included kinesiology, IgG testing, and pulse test. Almost half of the videos depicted a non‐IgE‐mediated reaction (49.0%).Videos by professional societies had the highest FA‐DQS (7.27). Scores for videos by professional societies were significantly different from other sources (P < .001). There was a high degree of agreement among reviewers (ICC = 0.820; P < .001). Conclusion: YouTube videos on food allergy frequently recommend controversial diagnostics and commonly depict non‐IgE‐mediated reactions. There is a need for high‐quality, evidence‐based, educational videos on food allergy.

No description available.

Background: Prenatal exposure to perfluoroalkyl substances (PFAS) has been associated with lower birth weight in epidemiologic studies. This association could be attributable to glomerular filtration rate (GFR), which is related to PFAS concentration and birth weight. Objectives: We used a physiologically based pharmacokinetic (PBPK) model of pregnancy to assess how much of the PFAS–birth weight association observed in epidemiologic studies might be attributable to GFR. Methods: We modified a PBPK model to reflect the association of GFR with birth weight (estimated from three studies of GFR and birth weight) and used it to simulate PFAS concentrations in maternal and cord plasma. The model was run 250,000 times, with variation in parameters, to simulate a population. Simulated data were analyzed to evaluate the association between PFAS levels and birth weight due to GFR. We compared simulated estimates with those from a meta-analysis of epidemiologic data. Results: The reduction in birth weight for each 1-ng/mL increase in simulated cord plasma for perfluorooctane sulfonate (PFOS) was 2.72 g (95% CI: –3.40, –2.04), and for perfluorooctanoic acid (PFOA) was 7.13 g (95% CI: –8.46, –5.80); results based on maternal plasma at term were similar. Results were sensitive to variations in PFAS level distributions and the strength of the GFR–birth weight association. In comparison, our meta-analysis of epidemiologic studies suggested that each 1-ng/mL increase in prenatal PFOS and PFOA levels was associated with 5.00 g (95% CI: –21.66, –7.78) and 14.72 g (95% CI: –8.92, –1.09) reductions in birth weight, respectively. Conclusion: Results of our simulations suggest that a substantial proportion of the association between prenatal PFAS and birth weight may be attributable to confounding by GFR and that confounding by GFR may be more important in studies with sample collection later in pregnancy.

We study nonlinear least-squares problem that can be transformed to linear problem by change of variables. We derive a general formula for the statistically optimal weights and prove that the resulting linear regression gives an optimal estimate (which satisfies an analogue of the Rao–Cramer lower bound) in the limit of small noise.

BACKGROUND: Behavioral risk factors are known to co-occur among youth, and to increase risks of chronic diseases morbidity and mortality later in life. However, little is known about determinants of multiple chronic disease behavioral risk factors, particularly among youth. Previous studies have been cross-sectional and carried out without a sound theoretical framework. METHODS: Using longitudinal data (n = 1135) from Cycle 4 (2000-2001), Cycle 5 (2002-2003) and Cycle 6 (2004-2005) of the National Longitudinal Survey of Children and Youth, a nationally representative sample of Canadian children who are followed biennially, the present study examines the influence of a set of conceptually-related individual/social distal variables (variables situated at an intermediate distance from behaviors), and individual/social ultimate variables (variables situated at an utmost distance from behaviors) on the rate of occurrence of multiple behavioral risk factors (physical inactivity, sedentary behavior, tobacco smoking, alcohol drinking, and high body mass index) in a sample of children aged 10-11 years at baseline. Multiple behavioral risk factors were assessed using a multiple risk factor score. All statistical analyses were performed using SAS, version 9.1, and SUDAAN, version 9.01. RESULTS: Multivariate longitudinal Poisson models showed that social distal variables including parental/peer smoking and peer drinking (Log-likelihood ratio (LLR) = 187.86, degrees of freedom (DF) = 8, p < .001), as well as individual distal variables including low self-esteem (LLR = 76.94, DF = 4, p < .001) increased the rate of occurrence of multiple behavioral risk factors. Individual ultimate variables including age, sex, and anxiety (LLR = 9.34, DF = 3, p < .05), as well as social ultimate variables including family socioeconomic status, and family structure (LLR = 10.93, DF = 5, p = .05) contributed minimally to the rate of co-occurrence of behavioral risk factors. CONCLUSIONS: The results suggest targeting individual/social distal variables in prevention programs of multiple chronic disease behavioral risk factors among youth.

Introduction Epidemiologic data supporting the role of organochlorine pesticides in pubertal development are limited. Methods Using a nested case-control design, serum collected during pregnancy from mothers of 218 girls who reported menarche before 11.5 years of age (cases) and 230 girls who reported menarche at or after 11.5 years of age (controls) was analyzed for 9 organochlorines and metabolites. We analyzed the association between in utero organochlorine concentrations and early menarche using multivariate logistic regression controlling for mother's age at menarche, or mother's prenatal BMI. Results We did not observe an association between in utero exposure to HCB, β-HCH, ϒ-HCH, p,p′-DDT, p,p′-DDE, oxychlordane or trans-nonachlor and early menarche. Conclusions This study is the first to examine the association between in utero exposure to HCB, β-HCH, ϒ-HCH, oxychlordane or trans-nonachlor and early menarche. In utero exposure to organochlorine pesticides does not appear to have a role in the timing of menarche in this study.

Physical fights among middle school students is a problem in our school systems, with 24.7% of students having been in a physical fight one or more times in 2013. The purpose of this study was to estimate the extent to which physical fights among middle school students in Tennessee was associated with demographic factors (age, sex and race) and to identify individual level factors that influence the likelihood of middle school students engaging in a physical fight.The 2013 Tennessee Youth Risk Behavior Survey (YBRS) data was used for this study, which is an annual cross-sectional school data collected by the National Center for Health Statistics of the Center for Disease Control and Prevention. A total of 5589 Tennessee Middle school students were included in the analysis. The outcome variable was physical fighting. Explanatory variables included demographic variables, life styles and health behavior risk factors. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were reported.The analyses indicate that male students were more likely to be involved in a physical fight than the female students (OR 2.89, 95% CI 2.49-3.36) and white students were less likely to be involved in a physical fight than the non-White students (OR 0.50, 95% CI 0.43-0.58). For every one year increase in age, the relative odds of being involved in a physical fight increased by 9.4% (OR 1.09, 95% CI 1.02-1.18). Similarly, students who ever tried to commit suicide (OR 1.89, 95% CI 1.39-2.53), drink alcohol (OR 2.48, 95% CI 2.02-3.05) and smoke cigarettes (OR 1.95, 95% CI 1.56-2.44) were more likely to be involved in a physical fight than those who did not. Students who carried a weapon were more likely to be involved in a physical fight than those students who did not (OR 2.72, 95% CI 2.31-3.20). While Students who watched television for 3 or more hours per day were more likely to engage in physical fights (OR 1.20, 95%CI 1.04-1.39) than students who did not, students with school grades A and B (OR 0.58, 95% CI 0.49-0.68), feeling safe and secure at school (OR 0.73, 95% CI 0.62-0.87), sleeping eight or more hours per day (OR 0.80, 95% CI 0.69-0.92) were less likely to be involved in a fight in school than other students.Age, gender, race, smoking, alcohol, use of marijuana, sleeping time, school performance, school safety environment, suicide attempt and TV time were potential risk factors associated with physical fights among middle school students. Strategies to reduce physical fights among students in Tennessean middle schools are needed.

INTRODUCTION: The risk factors for cardiovascular disease (CVD) are associated with coronary atherosclerosis and having multiple risk factors potentiates atherosclerosis. This study examined the prevalence of multiple biological and lifestyle/behavioral risk factors and their association with coronary artery calcium (CAC), a marker for subclinical coronary atherosclerosis. METHODS: This is a cross-sectional study of 1607 community-dwelling asymptomatic individuals from central Appalachia who participated in CAC screening between January 2011 and December 2012. Data on demographics (sex and age) and 7 traditional risk factors for coronary artery disease (CAD) were collected and categorized into 5 groups (0-1, 2, 3, 4, and ≥5). Prevalence of these risk factors and CAC scores (0, 1-99, 100-399, ≥400) were assessed, and the impact of the number of risk factors on CAC scores were delineated using multiple logistic regression. RESULTS: Over 98% of participants had ≥1 risk factor. While obesity, diabetes, hypertension, and family history of CAD significantly increased the odds of having CAC, CAC scores significantly increased with number of risk factors. After adjusting for demographic factors, having 3, 4, and ≥5 risk factors was significantly associated with increased odds of having higher CAC scores when compared to zero CAC score by more than one and half times [OR=1.65, CI (1.20-2.25)], two times [OR=2.32, CI (1.67-3.23)] and three times [OR=3.45, CI (2.42-4.92)], respectively. CONCLUSION: The high prevalence of multiple risk factors in the study population suggests the need for aggressive multiple risk factors interventions for primary prevention of CAD, which could address CVD health disparities.

Secondhand smoke (SHS) is a harmful mixture of over 4000 chemicals released from the burning of a cigarette. It has been classified as a Class A carcinogen and exposure to SHS has been proven to be related to negative health effects in humans. Children exposed to SHS are more susceptible to negative health effects because they have higher breathing rates and immature, developing bodies. SHS has been associated with many childhood diseases, including asthma, inner ear infections, and pneumonia. SHS exposure in confined areas, such as inside a motor vehicle, is of concern due to the increased toxicity level of the SHS. The purpose of this cross-sectional study was to assess the factors associated with those who smoke in a car containing children and to determine if the estimated prevalence of those who smoke in a vehicle with children has decreased since legislation was passed in Farmington Maine in 2008. Observations were taken at different times of the day and in different seasons. Each observation period consisted of a pair of researchers whom stood at the edge of the roadside, at 7 observations sites located throughout Farmington, Maine. When a vehicle passed, the researchers recorded the child passenger(s) estimated age(s), and the adult passenger(s) estimated age(s), gender, and smoking status. Site locations were chosen based upon ease of observation and neighborhood characteristics that were used as a proxy for socioeconomic status (SES) to the location. Adult data (n=3937) were used to calculate the estimated prevalence and factors of violation. Of all adult observations from 2008 to 2010, 8.26% were observed smoking in a vehicle containing a child, 63.38% of which were male. The estimated prevalence of those smoking in a vehicle containing children decreased from 13.08% (P < .0001), when the law was first enacted in the fall of 2008, to 7.40% (P < .0001) in the fall of 2010. Smoking in vehicles containing children was observed more frequently at sites that were estimated to have a lower SES near them, such as the fairgrounds [(OR=4.48, CI95 (2.49-8.09)] and at the tobacco store location [(OR=7.47, CI95 (4.29-13.01)]. In the final model, gender was found to be significantly associated with smoking in a vehicle containing a child, with males having increased odds of violation [OR=3.13, CI95 (2.44-4.01)]. However, when stratifying by gender, there were significant differences between site locations, dates, and time of the day that males or females were observed smoking. After adjusting for gender, site location, and age, adults observed in the Fall of 2008 were significantly more likely to be smoking in vehicle than those observed in the Fall of 2010 [OR=2.25, CI95 (1.64-3.09)]. The change in prevalence between dates indicates that smoking in a vehicle not only decreased over time, but also that season could have an effect on smoking in vehicle containing children behavior.