BMI Is Accurate Test For Obesity In Young Girls, But Inadequate For Women.(Body mass index )

2001 APR 19 - (NewsRx.com & NewsRx.net) -- by Susan Hasty, staff medical writer - Body mass index (BMI) calculations are fairly accurate in screening for obesity in 10- and 11 -year-old girls, but should be supplemented with other methods in young women 16 years and older, researchers in Brazil say.

M.A. Sampei and colleagues at the Escola Paulista de Medicina, Universidade Federal De Sao Paulo, compared various obesity screening methods and found that BMI correlated well with three other methods in young girls, but was not very accurate for girls as they grew older. The Sampei team studied 436 Japanese and Caucasian girls in two age groups: 10- to 11-year-olds (pre-menarche) and 16- to 17-year-olds (post-menarche).

Using population data from a national survey, Sampei and associates set the BMI cutoff for thinness at the fifth percentile and obesity was set at the 85th percentile. The girls' body composition was then measured using foot-to-foot bioelectrical impedance analysis (BIA), near-infrared interactance (NIR), and Slaughter skinfold equations (SKI), the researchers said.

The statistical analysis of the measurements was calculated with two cut-off points for obesity, 28% and 30% ("Comparison of the body mass index to other methods of body fat evaluation in ethnic Japanese and Caucasian adolescent girls," International Journal of Obesity, March 2001; 25(3):400-408).

BMI was closely correlated with the other methods in the younger girls, Sampei et al. reported. The major agreements were: in Japanese adolescents BMI x NIR = 82.3% ...