title: BMI trends, socioeconomic status, and the choice of dataset.
abstract: OBJECTIVE
  This study is a descriptive investigation of trends in BMI in the USA over time, across race/ethnicity, gender, and socioeconomic status (SES) groups, and across different datasets.
  
  
  METHODS
  The study analyzes micro-level data from three widely used cross-sectional US health datasets: the National Health and Nutrition Examination Survey (NHANES), the National Health Interview Survey (NHIS), and the Behavioral Risk Factor Surveillance System (BRFSS), from the 1970s to 2008. Consistent race/ethnicity and SES groups are constructed for all datasets. SES is measured by education and income. Focusing on adults aged 20-74 years, the study estimates BMI time trends, distributional shifts, and incremental associations (gradients) with SES.
  
  
  RESULTS
  SES-BMI gradients are consistently larger for women than for men, differ across race/ethnicity groups, and are similar across datasets. Trends in mean BMI are comparable across White, Black and Hispanic males, while Hispanic females range between White and Black females. Self-reported BMI in the NHANES differs markedly from self-reports in the NHIS and BRFSS.
  
  
  CONCLUSIONS
  The NHANES, NHIS, and BRFSS provide similar evidence regarding BMI trends over time and across race/ethnicity, gender, and SES groups. Racial disparities in BMI remain after adjusting for SES and should be studied further.
authors.affiliation: HealthCore Inc., 800 Delaware Avenue, Wilmington, DE 19801, USA. mjgrabner@gmail.com
authors.forename: Michael
authors.initials: M
authors.lastname: Grabner
mesh_terms: D000328:Adult; D001741:Black or African American; D000368:Aged; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D004522:Educational Status; D005260:Female; D054624:Health Status Disparities; D006306:Health Surveys; D006630:Hispanic or Latino; D006801:Humans; D007182:Income; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000208:ethnology; D015995:Prevalence; D057566:Self Report; D012737:Sex Factors; D012923:Social Class; D014481:United States / Q000453:epidemiology; D044465:White People; D055815:Young Adult