[Analysis of HIV infection status and the related factors among male students who have sex with men from voluntary counseling and testing clinics by classification tree model in Changzhou City, Jiangsu Province].

To analysis the status of HIV infection and the related factors among students of men who have sex with men (MSM) from voluntary counseling and testing (VCT) clinics in Changzhoucity Jiangsu province. A total of 236 subjects with previous male sexual history, 16-25 years of age and less than 3 months of confirmation time of HIV positive infection were recruited in Changzhou from January 2014 to December 2017. Questionnaires were conducted and plasma samples were collected for selenium and HIV antibody testing. The relevant factors of HIV infection among MSM were screened by classification tree model. The model was evaluated using cross validation and receiver operating characteristic (ROC) curve. The age of subjects was (20.76±1.97) years old. The age of the first sex with men was (19.14±1.85) years old and the plasma selenium content was (82.59±11.99) ng/ml. Of the 236 subjects, 74.58% (176 cases) were college students or undergraduates; 8.90% (21 cases) were diagnosed with venereal diseases in the last year; 80.93% (191 cases) received health services in the last year, and the positive rate of HIV antibody was 25.00% (59 cases). Four relevant factors were screened by the classification tree model, including the diagnosis of sexual transmitted diseases (STDs) in the last year, health services in the last year, plasma selenium level and education level. The most important factor was whether STDs were diagnosed in the last year. The estimate of re-substitution and cross-validation of the classification tree model was 0.186 and 0.195, and the standard error was 0.025 and 0.026, respectively. The area under the ROC was 0.706 (0.001). The MSM HIV antibody positive rate of VCT students in Changzhou City, Jiangsu Province was 25.0%. The diagnosis of STDs in the last year, receiving health services in the last year, plasma selenium level and education level were relevant factors of HIV infection.