Table 2.

Cox regression analysis of HIV seroconversion among men who have sex with men in the training dataset.

Characteristics and subgroup		Univariate analysis		Multivariate analysis
		cHRa (95% CI)	P value	aHRb (95% CI)	P value
Age (years)
	≤24	1.00
	>24	0.98 (0.62-1.54)	.92	—c	—
Local residence
	Yes	1.00
	No	0.97 (0.61-1.54)	.89	—	—
Ethnicity
	Non-Han	1.00
	Han	1.09 (0.58-2.07)	.78	—	—
Monthly income (US$)
	<430	1.00
	≥430	0.89 (0.70-1.14)	.36	—	—
Education
	Less than high school	1.00
	High school	0.72 (0.40-1.31)	.29	—	—
	College and above	1.09 (0.65-1.84)	.75	—	—
Marital status
	Single	1.00
	Married or cohabiting with a partner	0.50 (0.27-0.91)	.02	—	—
AIDS knowledge scores
	<8	1.00
	8	0.86 (0.53-1.39)	.54	—	—
Age of sexual debut (years)
	< 30	1.00
	≥ 30	0.14 (0.02-0.98)	.02	—	—
Main venue used to seek male sexual partners
	Internet	1.81 (1.08-3.04)	.02	2.70 (1.02-7.14)	.046
	Bars/dance halls	5.58 (2.09-14.93)	<.001	7.84 (2.64-22.91)	.03
	Parks/public baths	1.00
Number of male sexual partners
	<3	1.00
	≥3	2.06 (1.29-3.28)	.002	—	—
Had condomless insertive anal intercourse
	Yes	0.66 (0.41-1.07)	.09	0.22 (0.09-0.55)	.001
	No	1.00		1.00
Had condomless receptive anal intercourse
	Yes	1.60 (1.00-2.50)	.047	3.01 (1.48-6.16)	.003
	No	1.00		1.00
Rush poppers use
	Yes	2.34 (1.10-5.00)	.004	2.40 (1.10-5.27)	.03
	No	1.00		1.00
Tested positive for syphilis
	Yes	1.59 (0.85-2.98)	.15	—	—
	No	1.00

^acHR: crude hazard ratio.

^baHR: adjusted hazard ratio.

^cNot applicable.