[Analysis on influencing factors of unprotected sexual behavior among men who have sex with men based on structural equation model].

Objective: To analyze the influencing factors and mechanism for unprotected sexual behavior of men who have sex with men (MSM) in China. Methods: MSM who are more than 16 years old and have had homosexual sexual behaviors in recent years were recruited from five cities (Tianjin, Harbin, Nanjing, Chongqing and Xi'an) with active MSM population during 2013-2014 through network, site recruitment and peer recommendation using convenient sampling method. 3 519 subjects were included in this study. The sexual behavior related information of MSM in five cities was investigated using questionnaires. The confirmatory factor analysis was used to construct the measurement model by using the robust estimation method based on the weighted least square method to estimate parameters, and the final model was determined through evaluation and modification. Results: A total of 3 519 subjects were (29.9±8.76) years old, with a clear sexual orientation of 3 223 (91.6%), and 2 287 (65.0%) were aware of free HIV/AIDS treatment policies. The proportion of using condom last time was 77.2% (n=2 718), and the proportion of using condom every time was 36.9% (n=1 299) and 43.2% (n=1 521) respectively for the past six months with fixed and temporary partners. Structural equation model provided a good fit, the root mean square error of approximation, comparative fit index and non-normed fit index was 0.07, 0.97, 0.95, respectively. Knowing AIDS knowledge, educational level and sexual orientation had direct effects on unprotected sexual behavior, and the path coefficients were 0.179,-0.049 and -0.159, respectively. While the role of interventions was indirect, the path coefficient was 0.147. Conclusion: Lower education and unclear sexual orientation are disadvantages for reducing unprotected sexual behavior. Interventions mainly affect the unprotected sexual behavior by improving the level of HIV/AIDS knowledge. Increasing the comprehensive knowledge of MSM through intervention should be highly valued.