Moderate agreement between body mass index and measures of waist circumference in the identification of overweight among 5-year-old children; the 'Be active, eat right' study

Background: Body mass index (BMI) is a common indirect method to assess weight status among children. There is evidence that BMI data alone can underestimate overweight-related health risk and that waist circumference (WC) should also be measured. In this study we investigated the agreement between BMI and WC and BMI and the waist-height ratio (WHtR) when used to identify overweight among children. Methods: This cross-sectional population-based study uses baseline data from 5-year-olds (n = 7703) collected by healthcare professionals for the 'Be active, eat right' study. Results: According to age-specific and sex-specific cut-off points for BMI (IOTF, 2000) and WC (Fredriks et al., 2005), the prevalence of overweight (obesity included) was 7.0% and 7.1% among boys, and 11.6% and 10.1% among girls, respectively. For the WHtR the 90