Self-reported waist circumference: a screening tool for classifying children with overweight/obesity and...

The objectives of this study were twofold - (i) to assess the agreement between self-reported waist circumference (SRWC) and assessor measured waist circumference (MWC) and (ii) to evaluate the diagnostic ability of SRWC for classifying (i) a clustering of cardiometabolic risk factors (CMRFs) and (ii) overweight/obese status in Hong Kong Chinese children aged 6-18 years.

A cross-sectional study with cluster random sampling was conducted. A self-administrated questionnaire, which included demographic data, body weight, body height and waist circumference, was given to children to bring home for completion. Children were asked to return the questionnaire and fast themselves for at least 8 h on the day of the survey. Anthropometric measurements and blood pressure were taken by trained research staff and fasting blood samples were collected for measurements of fasting plasma glucose, total cholesterol, triglyceride, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol.

A total of 515 boys and 711 girls were included in the data analysis. Agreement between SRWC and MWC was assessed by intra-class correlation coefficient and it ranged from 0.77 to 0.87. The ability of sex-specific SRWC values to classify children with a clustering of CMRFs and overweight/obesity exhibited moderately high to high sensitivity and specificity, and the area under the receiver operating characteristics ranged from acceptable to excellent (from 0.76 to 0.84).

SRWC has good agreement with MWC and could be used as a screening tool to classify children with a clustering of CMRFs and overweight/obesity status in Hong Kong Chinese children.