Performance of models selected during the development stage (using recent infection as the outcome), here validated using acute HIV infection cases as the outcome.

All models are based on acute HIV infection among persons undergoing HIV testing at the San Francisco City Clinic from 2004–2007 (validation data; n = 12252; excludes recent and longstanding infections).1Key to checklists: MSM (person is a man who had sex with male partner(s)); IDU (any history of injection drug use); +partner (person had a partner known to be HIV positive); uRAI (engaged in unprotected receptive anal intercourse); STI (had a sexually transmitted infection within the past 2 years or since the last HIV test); AI (engaged in any anal intercourse, regardless of sex or gender); uAI (engaged in unprotected anal intercourse, regardless of sex or gender); RAI (engaged in receptive anal intercourse, regardless of sex or gender); uRAI (engaged in unprotected receptive anal intercourse, regardless of sex or gender).