Background: The Perceived Stress Scale (PSS) is a globally used and self-report scale measuring perceived stress. Three versions of PSS (PSS-14, PSS-10 and PSS-4) are available which comprise 14, 10 and 4 items respectively. However, the Chinese version of the PSS has not yet been validated in a large community-based general population. The aims of this study were to evaluate the psychometric properties of the Chinese PSS in a large community-based general population and to compare the appropriateness of the three versions of PSS. Methods: A total of 9507 adults with at least a junior high school education and completed PSS-14 from the China Health and Nutrition Survey were involved in this study. The internal consistency reliability of PSS was assessed using Cronbach's alpha coefficient and confirmatory factor analysis was employed to test the construct validity. Modification index was used for model extension and the critical ratio was used for model restriction. Results: The internal consistency coefficients were satisfactory for PSS-14 and PSS-10, but not for PSS-4. The corresponding Cronbach's alpha were 0.830, 0.754 and 0.473 respectively. A 2-factor structure was confirmed for the PSS-14 and PSS-10, and all items' standardized factor loadings exceeded 0.4 for either negative or positive factors. Given that item 12 loaded on both negative and positive factors for PSS-14 and the goodness of fit for PSS-14 was not acceptable, PSS-13 (PSS-14 excluding item 12) was studied. The construct validities of PSS-13 and PSS-10 were satisfactory, but the goodness of fit for PSS-10 were better than that for PSS-13. Conclusions: PSS-13 (PSS-14 excluding item 12) and PSS-10 have satisfactory psychometric properties. PSS-10 are more applicable to measure the perceived stress than PSS-13 in a large community-based general population in China.

BackgroundThe prevalence of childhood overweight and obesity in developed countries appears to be plateauing. The purpose of this study was to provide the most recent data on the prevalence and trends in overweight and obesity among Chinese children and adolescents from 2011 to 2015.MethodsWe used data collected in the China Health and Nutrition Survey (CHNS) and China Nutritional Transition Cohort Study (CNTCS). We used two waves of the survey in 12 provinces conducted in 2011 (aged 7–18 years; n = 1458) and 2015 (aged 7–18 years; n = 1084) to perform a trend analysis. We used data collected in 15 provinces (aged 7–18 years; n = 1617) to estimate the prevalence of overweight and obesity among Chinese children and adolescents in 2015.ResultsIn 2015, based on the Working Group for Obesity in China (WGOC) criteria, the prevalence of overweight and obesity were 14.0% (95% CI, 11.6–16.3) and 10.5% (95% CI, 8.4–12.6) in boys, and 9.7% (95% CI, 7.7–11.8) and 7.1% (95% CI, 5.2–8.9) in girls, respectively. The increase in BMI z-scores from 2011 to 2015 was statistically significant among adolescents (p = 0.0083), but not among children. No significant changes were observed in prevalence of overweight and obesity between 2011 and 2015, excepting adolescents aged 12–18 years (p = 0.0086).ConclusionsSince 2011, overweight has remained stable, and obesity has stabilized in children, though not in adolescents. Although levels of childhood overweight and obesity in China are not high compared to other developed countries, they remain concerning enough that effective policies and interventions need to be sustained and intensified for lowering rates of childhood overweight and obesity.

Pathogenesis and genetic factors influencing predisposition to antituberculosis drug-induced hepatotoxicity (ATDH) are not clear. Polymorphism at the genetic locus of a drug and xenobiotic compound metabolizing enzyme, N-acetyltransferase type 2 (NAT2), is reported to be associated with the excess generation of toxic reactive metabolites. To date, many case-control studies have been carried out to investigate the relationship between the NAT2 polymorphisms and ATDH, but the results have been inconsistent. To investigate this inconsistency, a meta-analysis was performed. Databases including PubMed, Web of Science, EMBASE and CNKI were searched to find relevant studies. A total of 26 case-control studies, involving 1,198 cases and 2,921 controls were included. Overall, we found significant association between slow acetylator genotype of NAT2 and ATDH (OR = 3.10, 95% CI: 2.47-3.88, P < 10(-5)). Significant results were also found in East Asians, South Asians, Brazilians and Middle Eastern when stratified by ethnicity. However, no significant associations were found for Caucasians. This meta-analysis demonstrated that the slow acetylator genotype of NAT2 is a risk factor associated with increased ATDH susceptibility, but these associations vary in different ethnic populations.

The aim of this study was to examine usual daily micronutrient intake of Chinese children based on data from the 2011 China Health and Nutrition Survey. We analyzed data from 4 to 17-year-old participants, who provided dietary data on three consecutive days combined with the household weighing method in 2011. Usual daily intake of each nutrient was estimated using a mixed effects model based on the China Food Composition published in 2009. The means, medians and percentages below Estimated Average Requirements (EAR) were reported for selected micronutrients, including calcium, sodium, potassium, iron, zinc, selenium, vitamin A, thiamine, riboflavin and vitamin C. For sodium and potassium, the means and the distribution of intakes were compared to the Adequate Intake (AI) level. The average usual daily intakes of all micronutrients increase with age, and the intakes of boys were found to be higher than girls in the same age group. The average calcium intake increased from 272 mg/day in 4–6 years to 391 mg/day in 14–17 years, but the percentage of inadequate calcium intake remained very high (>96%). The prevalence of inadequacy of calcium was the highest among the mineral nutrients reported in this study. As the requirements of micronutrients increased with age, the percentage of subjects with inadequate intake increased in the 11–17 years age groups. Among 14–17 years group, the percentages of study participants with dietary intakes of calcium, iron, zinc, selenium, vitamin A, thiamine, riboflavin and vitamin C below the EAR were 96.8%, 18.8%, 37.6%, 72.8%, 36.8%, 91.8%. 85.9% and 75.5%, respectively. Among 11–13 years group, the percentages of study participants with dietary intakes of iron, zinc and vitamin A below the EAR were 23.5%, 41.5%, and 41.6%, respectively. Thus, micronutrient deficiency is a problem in Chinese children. Nutrition education and intervention programs are needed to address these nutritional gaps.

This paper is the result of a nationwide study of polling place dynamics in the 2016 presidential election. Research teams, recruited from local colleges and universities and located in twenty-eight election jurisdictions across the United States, observed and timed voters as they entered the queue at their respective polling places and then voted. We report results about four specific polling place operations and practices: the length of the check-in line, the number of voters leaving the check-in line once they have joined it, the time for a voter to check in to vote (i.e., verify voter’s identification and obtain a ballot), and the time to complete a ballot. Long lines, waiting times, and times to vote are closely related to time of day (mornings are busiest for polling places). We found the recent adoption of photographic voter identification (ID) requirements to have a disparate effect on the time to check in among white and nonwhite polling places. In majority-white polling places, scanning a voter’s driver’s license speeds up the check-in process. In majority nonwhite polling locations, the effect of strict voter ID requirements increases time to check in, albeit modestly.

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Studies that evaluate determinants of residential water demand typically use data from a single spatial scale. Although household‐scale data are preferred, especially when econometric models are used, researchers may be limited to aggregate data. There is little, if any, empirical analysis to assess whether spatial scale may lead to ecological fallacy problems in residential water use research. Using linear mixed‐effects models, we compare the results for the relationship of single‐family water use with its determinants using data from the household and census tract scales in the city of Phoenix. Model results between the household and census tract scale are similar suggesting the ecological fallacy may not be significant. Common significant determinants on these two spatial scales include household size, household income, house age, pool size, irrigable lot size, precipitation, and temperature. We also use city/town scale data from the Phoenix metropolitan area to parameterize the linear mixed‐effects model. The difference in the parameter estimates of those common variables compared to the first two scales indicates there is spatial heterogeneity in the relationship between single‐family water use and its determinants among cities and towns. The negative relationship between single‐family house density and residential water use suggests that residential water consumption could be reduced through coordination of land use planning and water demand management.

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