Estimated PAR (95% CI) for risk factors for the prevalence and incidence of HIV infection in the MIRA trial
| Modifiable risk factors | PAR (95% CI)* (prevalence of HIV infection) | PAR (95% CI)* (incidence of HIV infection) |
| Combined effect† | 0.85 (0.84 to 0.87) | 0.77 (0.72 to 0.82) |
| Age at first sex (<15) | 0.26 (0.21 to 0.31) | 0.17 (0.10 to 0.21) |
| Less than high school‡ | 0.13 (0.10 to 0.17) | NA§ |
| Age at first sex | ||
| + Less than high school | 0.32 (0.27 to 0.38) | – |
| Not cohabiting | 0.39 (0.35 to 0.43) | 0.54 (0.46 to 0.62) |
| Number of lifetime male sex partners | ||
| Two | 0.12 (0.11 to 0.13) | 0.11 (0.09 to 0.15) |
| Three | 0.20 (0.18 to 0.21) | 0.13 (0.11 to 0.17) |
| Four or more | 0.41 (0.39 to 0.43) | 0.16 (0.13 to 0.20) |
| Biological risk factors | ||
| Tested positive for STI¶ | 0.05 (0.04 to 0.06) | 0.03 (0.02 to 0.05) |
| HSV2 | 0.82 (0.80 to 0.83) | 0.21 (0.14 to 0.31) |
↵* Age adjusted.
↵† Assumes all the risk factors removed from the target population.
↵‡ Less than 12 years of education.
↵§ Level of education was not determined to be significant predictor of HIV seroconversion.
↵¶ Chlamydia, gonorrhoea, syphilis or Trichomonas vaginalis at screening.
HSV2, herpes simplex virus 2; MIRA, Methods for Improving Reproductive Health in Africa; PAR, Population Attributable Risk; STI, sexually transmitted infection.