Tehran University of Medical Sciences Iranian Journal of Public Health 2251-6085 48 1 2019 01 16 69 76 Saejong PARK Department of Sports Sciences, Korea Institute of Sport Science, Seoul, Korea Dong-Sik CHUNG Department of Sports Sciences, Korea Institute of Sport Science, Seoul, Korea Byoung-Goo KO Department of Sports Sciences, Korea Institute of Sport Science, Seoul, Korea Hong-Sun SONG Department of Sports Sciences, Korea Institute of Sport Science, Seoul, Korea Kwang Jun KIM Department of Sports Sciences, Korea Institute of Sport Science, Seoul, Korea Jin-Wook CHUNG Department of Sports Culture, Dongguk University, Seoul, Korea Seunghee LEE Department of Physical Education, Korea University, Seoul, Korea Chul-Hyun KIM Department of Sports Medicine, Soonchunhyang University, Asan, Korea Younshin NAM Department of Sports for All, Duksung Women's University, Seoul, Korea Seungyun SHIN Department of Martial Arts, Yongin University, Yongin, Korea Hyo LEE Department of Sport and Health Sciences, Sangmyung University, Seoul, Korea Sochung CHUNG Department of Pediatrics, Konkuk University Medical Center, Research Institute of Medical Science, Konkuk University, School of Medicine, Seoul, Korea Hong-Yup AHN Department of Statistics, Dongguk University, Seoul, Korea Jeong Hun OH Seoul Physical Education Middle School, Seoul, Korea Wi-Young SO Sports and Health Care Major, College of Humanities and Arts, Korea National University of Transportation, Chungju-si, Korea 2019 01 16 Background: This study aimed to identify percent body fat cut-off points related to metabolic syndrome in a large sample of Korean adolescents. Methods: The subjects (n=2120; boys=1107, girls=1013) were middle and high school students aged 12–17 yr who participated in the Korean National Fitness Award Project in 2013. Percent body fat was estimated via eight-polar bioelectrical impedance analysis. Metabolic syndrome was classified using established standards based on the National Cholesterol Education Program with the definition modified for age. Age- and sex-specific percent body fat z-scores were calculated for every adolescent using skewness, median, and coefficient of variation curves to account for growth and development. Receiver operating characteristic curve analysis was used to identify the percent body fat cut-off points using percent body fat z-scores from skewness, median, and coefficient of variation curves as the test and metabolic syndrome as the criterion. Results: Based on the modified National Cholesterol Education Program criteria for metabolic syndrome, the areas under the receiver operating characteristic curve for percent body fat were 0.882 and 0.893 for boys and girls, respectively. The percent body fat percentiles were 82.2 and 87.3 for boys and girls, respectively. According to the skewness, median, and coefficient of variation curves, the percent body fat cut-off points based on the modified National Cholesterol Education Program criteria were 23.6%-25.7% for boys and 32.8%-37.3% for girls, both aged 12-17 yr. Age- and sex-specific percent body fat cut-off points were identified in relation to the metabolic syndrome status of Korean adolescents. Conclusion: These percent body fat cut-offs might be useful for identifying metabolic abnormality due to obesity in Korean adolescents.     https://ijph.tums.ac.ir/index.php/ijph/article/view/15940 https://ijph.tums.ac.ir/index.php/ijph/article/download/15940/6255