title: Ethnic variation in validity of classification of overweight and obesity using self-reported weight and height in American women and men: the Third National Health and Nutrition Examination Survey.
abstract: BACKGROUND
  Few data have been published on the validity of classification of overweight and obesity based on self-reported weight in representative samples of Hispanic as compared to other American populations despite the wide use of such data.
  
  
  OBJECTIVE
  To test the null hypothesis that ethnicity is unrelated to bias of mean body mass index (BMI) and to sensitivity of overweight or obesity (BMI > or = 25 kg/m2) derived from self-reported (SR) versus measured weight and height using measured BMI as the gold standard.
  
  
  METHODS
  Cross-sectional survey of a large national sample, the Third National Health and Nutrition Examination Survey (NHANES III) conducted in 1988-1994.
  
  
  METHODS
  American men and women aged 20 years and over (n = 15,025).
  
  
  METHODS
  SR height, weight, cigarette smoking, health status, and socio-demographic variables from home interview and measured weight and height.
  
  
  RESULTS
  In women and Mexican American (MA) men SR BMI underestimated true prevalence rates of overweight or obesity. For other men, no consistent difference was seen. Sensitivity of SR was similar in non-Hispanic European Americans (EA) and non-Hispanic African Americans (AA) but much lower in MA. Prevalence of obesity (BMI > or = 30 kg/m2) is consistently underestimated by self-report, the gap being greater for MA than for other women, but similar for MA and other men. The mean difference between self-reported and measured BMI was greater in MA (men -0.37, women -0.76 kg/m2) than in non-Hispanic EA (men -0.22, women -0.62 kg/m2). In a regression model with the difference between self-reported and measured BMI as the dependent variable, MA ethnicity was a significant (p < 0.01) predictor of the difference in men and in women. The effect of MA ethnicity could not be explained by socio-demographic variables, smoking or health status.
  
  
  CONCLUSIONS
  Under-estimation of the prevalence of overweight or obesity based on height and weight self-reported at interview varied significantly among ethnic groups independent of other variables.
authors.affiliation: Centers for Disease Control and Prevention, 3311 Toledo Road, Hyattsville, Maryland 20782, USA. rfg2@cdc.gov
authors.forename: R F
authors.initials: RF
authors.lastname: Gillum
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Sempos
mesh_terms: D000328:Adult; D001741:Black or African American; D001827:Body Height; D015992:Body Mass Index; D001835:Body Weight; D003430:Cross-Sectional Studies; D005006:Ethnicity; D005060:Europe / Q000208:ethnology; D005188:False Negative Reactions; D005260:Female; D006630:Hispanic or Latino; D006801:Humans; D008297:Male; D008800:Mexico / Q000208:ethnology; D008875:Middle Aged; D009749:Nutrition Surveys; D009765:Obesity / Q000145:classification* / Q000453:epidemiology; D012044:Regression Analysis; D015203:Reproducibility of Results; D012727:Sex Characteristics; D014481:United States