Objectives: This study compared the criteria or classification of Body Mass Index (BMI) by Centers for Disease Control and Prevention (CDC), International Obesity Task Force (IOTF) and World Health Organization (WHO) references and by waist circumference (WC).
Methods: The sample involved 966 students aged 10 to 16 years. The evaluation of weight status was verified according to CDC, IOTF, WHO criteria and WC curves for Portuguese adolescents.
Results: For classification of overweight and obesity, the agreement between the criteria of CDC and IOTF was the and WC (K = 0.34). In regard to evaluation of thinness, the agreement between all criteria of BMI was considered moderated to fair (K = 0.33-0.51) and a poor level of agreement between the BMI and WC (K = 0.14-0.16).
Conclusion: The highest level of agreement for thinness, overweight and obesity classification in adolescents was obtained with the IOTF and CDC criteria.