Objective:To analyze the accuracy of different BMI obesity screening criteria in discriminating the obesity of college students, and to provide a reference for formulation scientific and reasonable grouth and development evaluation criteria for students.

Methods:The bioelectrical impedance analysis (BIA) was used to measure BF of 1 977 non-sports-major-students. Based on WHO "golden standard" of BF% (BF>25% for male and BF >35% for female) for obesity, the accuracy, reliability, and benefits of different BMI screening standards for obesity were evaluated.

Results:The obesity rate was 11.6% according to the BF% standard, and was 2.0% and 8.2% based on BMI ≥28 kg/m2 and BMI ≥25 kg/m2, respectively; A higher specificity (0.999, 0.966) and a low sensitivity (0.175,0.450) were noticed when BMI≥28 kg/m2 and BMI≥25 kg/m2 was used as screening standard for obesity, especially among female(0.063,0.304); The reliability evaluation of consistency with "gold standard" of BMI≥25 kg/m2 was higher than BMI≥25 kg/m2; when BMI≥28 kg/m2 was used as screening standard for obesity, the positive predictive value was higher than negative predictive value, BMI≥25 kg/m2 was on the contrary.

Conclusion:BMI cannot adequately reflect body fat content of college students, especially for female; The standard for obesity diagnosis should be based on gender.