Objective: To compare childhood obesity prevalence in England and the United States using different criteria.
Subjects/methods: Participants included 2- to 17-year olds in the Health Survey for England (HSE, n=33 563) and the US National Health and Nutrition Examination Survey (NHANES, n=14 540) 1999 through 2006. Mean body mass index (BMI) and prevalence of obesity were compared using the UK 1990, US 2000 Centers for Disease Control and International Obesity Task Force (IOTF) criteria.
Results: English children at ages 2-5 years had a higher mean BMI than US children (mean difference (English minus US)=0.41 kg/m(2), 95% confidence intervals (CI) 0.31-0.52). At age ≥8 years, mean BMI was lower in England (for ages 8-11 years, mean difference = -1.00 kg/m(2), 95% CI -1.26 to -0.75; for ages 12-17 years, mean difference = -1.37 kg/m(2), 95% CI -1.59 to -1.14). The IOTF criteria produced the lowest estimates of obesity prevalence. The 2000 Centre for Disease Control and Prevention (CDC) criteria produced the highest estimates in younger children and the UK 1990 criteria produced the highest in adolescents. Children aged 2-5 years in England had higher prevalence of obesity than those in the United States when using the 2000 CDC and UK 1990 criteria. US adolescents had the highest prevalence of obesity by age group using each of the three criteria.
Conclusion: The 2000 CDC and UK 1990 criteria give a higher prevalence of obesity in England than in the United States at ages 2-5 years; however, at age ≥8 years, the reverse is true. Estimates of childhood obesity prevalence rely on the criteria used, which has implications for surveillance and clinical practice.