Table 1.
Subgroup analyses of included studies.
| Number of studies | Number of participants | aOR (95% CI) | I2 (%) | P-value for heterogeneity chi-square | |
|---|---|---|---|---|---|
| Overall | 33 | 117,293 | 0.93 (0.88, 0.99) | 54 | <0.0001 |
| By sex positioning | |||||
| Insertive | 11 | 15,946 | 1.16 (0.73, 1.83) | 14.6 | 0.31 |
| Insertive (after deleting Zeng et al.47)a | 10 | 0.51 (0.23, 1.11) | 0.00 | 0.89 | |
| Receptive | 6 | 9244 | 0.97 (0.74, 1.28) | 28.0 | 0.23 |
| By study regions | |||||
| Asia | 8 | 17,458 | 0.69 (0.58, 0.81) | 39.3 | 0.12 |
| Non-Asia | 25 | 99,835 | 0.97 (0.91, 1.03) | 45.0 | 0.007 |
| Asia + Africa | 9 | 17,821 | 0.62 (0.53, 0.73) | 70.1 | 0.001 |
| Non-Asia/non-Africa | 24 | 99,472 | 0.99 (0.93, 1.05) | 0.00 | 0.86 |
| By sample size | |||||
| Smaller size (<3000) | 24 | 22,510 | 0.70 (0.61, 0.82) | 39.3 | 0.024 |
| Larger size (⩾3000) | 9 | 94,783 | 0.98 (0.92, 1.04) | 52.3 | 0.033 |
| By study design | |||||
| Cross-sectional | 24 | 92,937 | 0.92 (0.87, 0.98) | 61.9 | <0.0001 |
| Cohort | 9 | 24,356 | 1.01 (0.86, 1.19) | 0.0 | 0.47 |
| By sampling strategy | |||||
| Convenience sampling | 17 | 54,235 | 0.95 (0.88, 1.03) | 41.6 | 0.037 |
| Non-convenience sampling | 16 | 63,058 | 0.92 (0.85, 0.99) | 63.6 | 0.000 |
| Non-probability-based | 28 | 100,448 | 0.95 (0.68, 1.34) | 0.0 | 0.67 |
| Probability-based | 5 | 16,845 | 0.93 (0.88, 0.99) | 59.6 | <0.0001 |
| By HIV testing | |||||
| Lab test | 27 | 99,896 | 0.93 (0.88, 0.99) | 59.4 | <0.0001 |
| Self-report | 6 | 17,397 | 0.95 (0.75, 1.20) | 4.0 | 0.39 |
| By VMMC | |||||
| Genital examination | 9 | 32,715 | 0.98 (0.90, 1.07) | 0.0 | 0.61 |
| Self-report | 24 | 84,578 | 0.90 (0.84, 0.97) | 62.1 | <0.0001 |
| By exposure and outcome measurement | |||||
| Using genital examination and laboratory testing | 9 | 32,715 | 0.98 (0.90, 1.07) | 0.0 | 0.61 |
| One measured | 18 | 67,181 | 0.93 (0.88, 0.99) | 59.4 | <0.0001 |
| Neither measured | 6 | 17,397 | 0.95 (0.75, 1.20) | 4.0 | 0.39 |
aOR: adjusted odds ratio; CI: confidence interval; VMMC: voluntary medical male circumcision.
a
The study (Zeng et al.47) is an outlier. After deleting, the odds of HIV risk among insertive MSM were lower compared to the odds of HIV risk among MSM who primarily practice receptive or versatile sex positioning.