Percentile Curves for Body-Mass Index, Waist Circumference, Waist-To-Height Ratio and Waist-To-Height Ratio(Exp) in Croatian Adolescents

Purpose: The main purpose of the present study was to establish percentile curves for body-mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR) and WHtR(exp) in adolescents. Methods: In this cross-sectional study, we recruited 1036 secondary-school students aged 15 to 18 years from eight randomly selected schools (55.3% girls). BMI, WC, WHtR and WHtR(exp) were calculated using standardized measuring protocol. The sex- and age-specific smoothed percentile curves with 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentile for each anthropometric measure were constructed using Cole's LMS method. Results: In boys, both BMI and WC percentile curves increased by age, yet the 95th percentile curve for WHtR and WHtR(exp) decreased by age. In girls, the 95th percentile curve for BMI remained unchanged through the age of 15 to 18 years, yet the 90th and 95th percentile curves for WC and WHtR decreased by age. Conclusion: This is the first study in Croatia to establish combined BMI, WC, WHtR and WHtR(exp) percentile curves and add some new insight on anthropometric measures in 15- to 18-year-old adolescents.