Waist circumference percentiles for 7-to 15-year-old Australian children

Aim: The purpose of this study was to develop age- and sex-specific reference values for waist circumference using data obtained from Australian children and adolescents. Methods: Subjects were 8439 7-to-15 y olds ( 4277 males and 4162 females) who participated in the 1985 Australian Health and Fitness Survey. Waist circumference ( WC) was measured in the standing position at the level of the umbilicus to the nearest 0.1 cm using a constant tension tape. Descriptive statistics for each whole-year age group ( e. g., 10.0-10.99 y, etc.) within sex were calculated. Construction of the smoothed centile curves was performed using the LMS method. Results: Mean WC increases in both males and females, with the values being similar between males and females prior to age 11 y, after which values are slightly higher in males. The range of values varied by age and sex groups but approximated 30 - 60 cm. Smoothed percentile curves and percentile values for the 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles are presented for boys and girls. WC increases with age in boys and girls, and boys have higher values than girls at nearly every age- specific percentile. Conclusions: These data can be added to the existing international reference values for WC of children and adolescents which should be used to create international cut-off points similar to those for the body mass index (BMI). Future studies should consider the immediate and long-term consequences of an elevated WC in children and also examine the interaction of BMI and WC on chronic disease risk factors.