| Sexual behaviour category in the past 3 months (mutually exclusive) | Definition |
| 1. Higher HIV risk CLS-D | CLS with HIV-negative or HIV-unknown serostatus partners (CLS-D) and either: not on ART at the time of the questionnaire or has latest clinic VL >50 c/mL. Includes n=8 participants who reported having CLS without specifying their partner(s) HIV serostatus |
| 2. Other CLS-D | Any other CLS with HIV-serodifferent partners (but not CLS-D higher HIV risk). Includes n=23 participants who reported having CLS without specifying their partner(s) HIV serostatus |
| 3. ‘CLS-C without CLS-D’ | CLS with HIV-seroconcordant (other HIV-positive) partners only (CLS-C), with no CLS-D partners |
| 4. Condom-protected sex | Condom-protected sex only |
| 5. No anal or vaginal sex |
ART, antiretroviral therapy; CLS, condomless sex; N=31 participants with ’possible ClS-D' (reported having CLS but did not specify partner(s) serostatus) were included as CLS-D in this classification20.