title: [Sensitivity and specificity of overweight classification of adolescents, Brazil].
abstract: OBJECTIVE
  To evaluate the prevalence, sensitivity and specificity of two risk classifications of obesity based on the body mass index (BMI).
  
  
  METHODS
  Five-hundred and two adolescents, aged 12-18 years, participants of a health and nutrition survey conducted in 1996 in the city of Rio de Janeiro, Brazil, were evaluated. The study variables included: weight, stature, BMI, and subscapular skinfold, according to sex and age. The BMI classifications were compared to a fatness classification based on the 90th percentile of subscapular skinfold thickness in American adolescents.
  
  
  RESULTS
  The prevalence of risk of obesity was higher when using the subscapular skinfold measurement (p<0.0001), compared to both BMI-based classifications, which showed similar values. Specificity was higher than sensitivity in both BMI-based classifications. The balance between sensitivity and specificity was close to the 70thBMI percentile for boys and girls below 14 years old. For boys older than 15 the cutoff value was the 50th percentile.
  
  
  CONCLUSIONS
  Both BMI-based classifications were more suitable to identify adolescents without obesity, and their sensitivities were too low for tracking risk of obesity.
authors.affiliation: Departamento de Nutrição Social, Instituto de Nutrição, Universidade Estadual do Rio de Janeiro, Rio de Janeiro, RJ, Brasil.
authors.forename: Vera
authors.initials: V
authors.lastname: Chiara
authors.forename: Rosely
authors.initials: R
authors.lastname: Sichieri
authors.forename: Patr cia D
authors.initials: Pc
authors.lastname: Martins
mesh_terms: D000293:Adolescent; D015992:Body Mass Index; D001835:Body Weight; D001938:Brazil / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D009765:Obesity / Q000145:classification / Q000175:diagnosis* / Q000453:epidemiology*; D011237:Predictive Value of Tests; D015995:Prevalence; D012307:Risk Factors; D012680:Sensitivity and Specificity; D017678:Sex Distribution; D012885:Skinfold Thickness; D014505:Urban Population
vernacular_title: Sensibilidade e especificidade de classificação de sobrepeso em adolescentes, Rio de Janeiro.