HIV screening in an urban emergency department: comparison of screening using an opt-in versus an opt-out approach.

OBJECTIVE: We compare outcomes of opt-in and opt-out HIV screening approaches in an urban emergency department.
METHODS: This was a 1-year prospective observational study comparing 2 6-month screening approaches. Eligibility for opt-in and opt-out screening was identical: aged 15 years or older, medically stable, and able to complete general consent. During the opt-in phase, triage nurses referred patients to HIV testers stationed at triage, who obtained separate opt-in written consent and performed rapid oral fluid tests. During the opt-out phase, registration staff conducted integrated opt-out consent and then referred patients to HIV testers. We assessed the proportion of potentially eligible patients who were offered screening (screening offer rate), the proportion offered screening who accepted (screening acceptance rate), the proportion who accepted screening and subsequently completed testing (test completion rate), and the proportion of potentially eligible patients who completed testing (overall screening rate) during each phase.
RESULTS: For the opt-in versus the opt-out phases, respectively, there were 23,236 potentially eligible patients versus 26,757, screening offer rate was 27.9% versus 75.8% (P<.001), screening acceptance rate was 62.7% versus 30.9% (P<.001), test completion rate was 99.8% versus 74.6% (P<.001), and overall screening rate was 17.4% versus 17.5% (P = .90).
CONCLUSION: A significantly higher proportion of patients were offered HIV screening with an opt-out approach at registration. However, this was offset by much higher screening acceptance and test completion rates with the opt-in approach at triage. Overall screening rates with the 2 approaches were nearly identical.