Patient choice in opt-in, active choice, and opt-out HIV screening: randomized clinical trial

Abstract

Study question: What is the effect of default test offers--opt-in, opt-out, and active choice--on the likelihood of acceptance of an HIV test among patients receiving care in an emergency department?

Methods: This was a randomized clinical trial conducted in the emergency department of an urban teaching hospital and regional trauma center. Patients aged 13-64 years were randomized to opt-in, opt-out, and active choice HIV test offers. The primary outcome was HIV test acceptance percentage. The Denver Risk Score was used to categorize patients as being at low, intermediate, or high risk of HIV infection.

Study answer and limitations: 38.0% (611/1607) of patients in the opt-in testing group accepted an HIV test, compared with 51.3% (815/1628) in the active choice arm (difference 13.3%, 95% confidence interval 9.8% to 16.7%) and 65.9% (1031/1565) in the opt-out arm (difference 27.9%, 24.4% to 31.3%). Compared with active choice testing, opt-out testing led to a 14.6 (11.1 to 18.1) percentage point increase in test acceptance. Patients identified as being at intermediate and high risk were more likely to accept testing than were those at low risk in all arms (difference 6.4% (3.4% to 9.3%) for intermediate and 8.3% (3.3% to 13.4%) for high risk). The opt-out effect was significantly smaller among those reporting high risk behaviors, but the active choice effect did not significantly vary by level of reported risk behavior. Patients consented to inclusion in the study after being offered an HIV test, and inclusion varied slightly by treatment assignment. The study took place at a single county hospital in a city that is somewhat unique with respect to HIV testing; although the test acceptance percentages themselves might vary, a different pattern for opt-in versus active choice versus opt-out test schemes would not be expected.

What this paper adds: Active choice is a distinct test regimen, with test acceptance patterns that may best approximate patients' true preferences. Opt-out regimens can substantially increase HIV testing, and opt-in schemes may reduce testing, compared with active choice testing.

Funding, competing interests, data sharing: This study was supported by grant NIA 1RC4AG039078 from the National Institute on Aging. The full dataset is available from the corresponding author. Consent for data sharing was not obtained, but the data are anonymized and risk of identification is low.Trial registration Clinical trials NCT01377857.

Fig 1 Flow chart of HIV Defaults Study. Of 5801 patients approached for inclusion in study, 4800 consented. Of those approached, 33.5%, 34.7%, and 31.8% were assigned to opt-in, active choice, and opt-out test treatments, respectively. The final study population comprised 33.5% opt-in, 33.9% active-choice, and 32.6% opt-out patients

Fig 2 HIV test acceptance percentage by risk of infection: unadjusted results. Test acceptance percentage is shown according to treatment assignment (opt-in, active choice, and opt-out), and according to risk of HIV infection. Lines indicate 95% confidence intervals. Numbers of patients from each risk category accepting and offered HIV testing under each treatment group are presented as numerator and denominator

Fig 3 Test acceptance percentage by study staff member; (a) is composite of study staff who saw fewer than 200 patients each; (b) to (i) are individual staff members who saw more than 200 patients each. Lines indicate 95% confidence intervals