Table 2 Factors associated with HIV infection among 3717 Chinese MSM

 NC-MSM

378 (10.9)

Ref.

0.55

Ref.

0.88

 MSM-buying

13 (12.6)

1.2 (0.7–2.1)

1.1 (0.5–2.5)

 MSM-selling

20 (13.4)

1.3 (0.8–2.1)

1.2 (0.5–2.6)

 No

333 (9.8)

Ref.

<0.001

Ref.

<0.001

 Yes

78 (23.9)

2.9 (2.2–3.8)

2.0 (1.4–2.8)

 No

275 (9.2)

Ref.

<0.001

Ref.

<0.001

 Yes

88 (21.5)

2.7 (2.1–3.5)

2.3 (1.7–3.1)

Age (per year)

1.0 (1.0–1.1)

0.001

1.0 (0.9–1.0)

0.24

 No

293 (10.4)

Ref.

0.018

Ref.

0.18

 Yes

118 (13.2)

1.3 (1.0–1.7)

1.2 (0.9–1.6)

 >6 months

317 (11.4)

Ref.

0.023

Ref.

0.031

 ≤6 months

42 (16.1)

1.5 (1.1–2.1)

1.5 (1.0–2.2)

 No

376 (11.9)

Ref.

<0.001

Ref.

0.002

 Yes

35 (6.4)

0.5 (0.4–0.7)

0.5 (0.3–0.8)

 College or above

210 (9.9)

Ref.

0.008

Ref.

0.15

 High school or below

201 (12.6)

1.3 (1.1–1.6)

1.2 (0.9–1.5)

 No

121 (10.5)

Ref.

0.6

Ref.

0.72

 Yes

284 (11.1)

1.1 (0.8–1.3)

1.1 (0.8–1.4)

 0–2

220 (9.5)

Ref.

<0.001

Ref.

0.023

 3–9

147 (14.0)

1.5 (1.2–1.9)

1.4 (1.1–1.8)

 ≥10

34 (11.6)

1.2 (0.8–1.8)

1.1 (0.7–1.7)

 No

237 (10.1)

Ref.

<0.001

Ref.

<0.001

 Yes

144 (16.3)

1.7 (1.4–2.1)

1.7 (1.3–2.2)

 No

123 (8.8)

Ref.

<0.001

Ref.

0.001

 Yes

288 (12.4)

1.5 (1.2–1.8)

1.5 (1.2–1.9)

 Receptive

265 (12.8)

Ref.

<0.001

Ref.

0.014

 Insertive

139 (9.0)

0.7 (0.5–0.8)

0.7 (0.6–0.9)