Body Weight Misperception and Weight Disorders among Chinese Children and Adolescents: A Latent Class Analysis.

Body misperception plays an important role in the development of weight and dietary disorders among children and adolescents. A school-based health promotion program (2014-2015) was conducted to promote the school health education and improve the teenagers' physical health among Chinese children and adolescents. Based on this program, we intended to examine weight status and weight misperception among Chinese children and adolescents and to explore the relationship between weight misperception and lifestyle behaviors. A total of 10 708 Chinese children and adolescents in 3rd and 7th grade from Shandong and Qinghai province participated in the program. The participants' dietary and activity patterns were clustered by latent class analysis (LCA). Logistic regression analysis was undertaken to explore the relationship between weight perception and demographic factors or dietary and activity patterns. Given the gender-specific difference of children and adolescents, analyses were separately conducted among boys and girls. The total prevalence of weight misperception was 44.50%. Boys, especially those in higher grade and living in wealthier district, were more likely to misperceive body weight. Girls were more likely to overestimate their weight (26.10%) while boys tended to underestimate the weight (28.32%). Three latent dietary and activity patterns including obesogenic pattern, malnourished pattern and healthy pattern were derived. The participants who had weight misperception were more likely to choose unhealthy dietary and exercise activities. The high prevalence of weight misperception was closely related to the unhealthy weight pattern and unhealthy dietary or exercise patterns. Our research found that most children and adolescents failed to perceive their weight correctly and boys tended to underestimate their weight while girls were subjected to overestimation. So, comprehensive intervention programs should focus on improving self-weight awareness, and appropriate guidance should be made to lead the adolescents to more healthy weight pattern.