. Author manuscript; available in PMC: 2017 Apr 1.

Published in final edited form as: J Acquir Immune Defic Syndr. 2016 Apr 1;71(4):444–451. doi: 10.1097/QAI.0000000000000856

Table 4.

Association between male circumcision and HIV, syphilis or HIV/syphilis co-infection among men who have sex with men in China

Circumcision status	Sample size (N=1053)^*	Adjusted odds ratio; OR (95% confidence interval)
Circumcision status	Sample size (N=1053)^*	A priori model^†	Secondary model (1)^‡	Secondary model (2)^§
HIV infection
Uncircumcised	975	Reference	Reference	Reference
Circumcised	78	0.53 (0.27, 1.02)	0.52 (0.25, 1.06)	0.47 (0.24, 0.90)

Syphilis infection
Uncircumcised	975	Reference	Reference	Reference
Circumcised	78	0.91 (0.51, 1.61)	0.94 (0.49, 1.78)	0.75 (0.42, 1.32)

N=1053 due to missing data on variables of circumcision, HIV status, or anal sex role/position.

^†

Adjusted for age, ethnicity, education, Beijing residency, number of lifetime male sexual partners, and anal sexual role/position.

^‡

Adjusted for those covariates in Table 2, including anal sexual role, that were significant at P<0.2.

^§

Adjusted for education after stepwise backward selection based on a 10% change in estimates.