Table S1. Collinearity test of independent variables.

Variables	Non standardized coefficients			Standardized coefficients	t	P	Tolerance	VIF
	β	SE		β
Abbreviation: SE=standard error; VIF=variance inflation factor.
Age	−0.020	0.026		−0.024	−0.757	0.449	0.679	1.472
Gender	−0.129	0.048		−0.074	−2.684	0.007	0.888	1.126
Registered residence	−0.073	0.029		−0.073	−2.540	0.011	0.821	1.218
Sexual orientation	−0.037	0.014		−0.072	−2.561	0.011	0.868	1.152
Marital status	−0.028	0.019		−0.045	−1.496	0.135	0.769	1.300
Education	−0.125	0.020		−0.206	−6.377	<0.001	0.655	1.526
Occupation	<0.001	0.007		<0.001	−0.015	0.988	0.967	1.034
Monthly income	0.019	0.015		0.038	1.248	0.212	0.735	1.360
Have you been vaccinated against flu?	0.001	0.030		0.001	0.021	0.983	0.974	1.026
Have any other sexually transmitted diseases?	−0.063	0.038		−0.044	−1.671	0.095	0.972	1.029
Have any other chronic diseases?	−0.048	0.024		−0.053	−1.973	0.049	0.937	1.067
Time of confirmed HIV infection	−0.019	0.023		−0.023	−0.818	0.414	0.858	1.165
Latest CD4 test results	0.011	0.016		0.018	0.688	0.492	0.963	1.038
Latest varial copies test results	−0.071	0.014		−0.149	−5.069	<0.001	0.793	1.261