Objective: To compare the body mass index (BMI) (calculated as weight in kilograms divided by the square of height in meters) and the prevalence of BMI at or above the 85th centile and 95th centile (overweight) in adolescents.
Design: Cross-sectional, nationally representative school-based surveys in 1997-1998 by means of identical data collection methods.
Setting: Austria, Czech Republic, Denmark, Flemish Belgium, Finland, France, Germany, Greece, Lithuania, Ireland, Israel, Portugal, Slovakia, Sweden, and the United States.
Participants: A total of 29 242 boys and girls, aged 13 and 15 years.
Main outcome measures: The BMI, BMI at or above the 85th centile, and BMI at or above the 95th centile (overweight) from self-reported height and weight.
Results: The highest prevalence of overweight was found in the United States and the lowest in Lithuania. On the basis of the study reference standard, the prevalence of overweight (percentage) in the United States was 12.6% in 13-year-old boys, 10.8% in 13-year-old girls, 13.9% in 15-year-old boys, and 15.1% in 15-year-old girls, all significantly increased. Prevalence of overweight in Lithuania was significantly below the expected 5%, with 1.8% in 13-year-old boys, 2.6% in 13-year-old girls, 0.8% in 15-year-old boys, and 2.1% in 15-year-old girls. Relative rankings among countries were similar for BMI at or above the 85th centile, although there were less dramatic differences at this level.
Conclusions: The highest prevalences of overweight were found in the United States, Ireland, Greece, and Portugal.