Prevention Effective Practice: Development and Preliminary Evaluation of a Proposed Composite Outcome for Status-Neutral HIV Prevention Research.

Status-neutral HIV prevention frameworks require outcome measures to evaluate prevention and care strategies across populations without separate endpoints for people living with and without HIV. We developed and conducted a preliminary evaluation of a proposed composite outcome measure, "prevention effective practice," integrating behavioral and biomedical prevention practices into a single binary outcome. Using longitudinal data from 392 transgender women not living with HIV in São Paulo, Brazil, we assessed whether prevention effective practice predicted subsequent HIV seroconversion. Prevention effective practice incorporated sufficient PrEP use, condom use, abstinence from sex, and absence of injection risk. Despite the small number of seroconversions (n = 11), prevention effective practice demonstrated preliminary predictive utility, with a Brier score of 0.0030, sensitivity of 0.59 (95%CI 0.56, 0.62), and specificity of 0.70 (95%CI 0.41, 0.99). These findings support further evaluation of prevention effective practice as a proposed status-neutral outcome measure, including validation among people living with HIV.