What’s the best way to encourage patients to get screened for HIV? Money is a time-honored effective incentive, but researchers from University of California say the default option may be even better. They conducted, to their knowledge, the first head-to-head study of 2 types of behavioral economics interventions (cash incentives vs opt-out) in any health behavior context. The working hypothesis was based on “nudge theory,” a concept in behavioral science, political theory, and economics that says using positive reinforcement and indirect suggestions can influence behavior and decision making.
In the study, patients aged 13 to 64 years were told the emergency department was offering rapid screening HIV tests, with results available within 2 hours. Then each patient was given a test offer: opt-in (“You can let me, your nurse, or your doctor know if you’d like a test today”); active choice (“Would you like a test today?”); or opt-out (“You will be tested unless you decline.”) Patients assigned to a positive monetary incentive were told “To encourage testing today we are offering a $1 (or $5 or $10) cash incentive.”
Of 8,715 patients, 4,831 (55%) accepted an HIV test. Those offered no monetary incentive accepted 52% of test offers. The $1 offer did not increase test acceptance, but the $5 and $10 offers increased acceptance rates by 10.5 and 15 percentage points, respectively. Active-choice increased acceptance by 11.5 percentage points compared with that of opt-in offers.
However, opt-out testing—essentially a default option—had the largest effect, increasing acceptance by 24 percentage points. The next most effective was the $10 incentive.
The researchers say the effects were consistent across all levels of patient risk of infection, although the effects were somewhat attenuated when defaults and incentives were used together. In general, higher risk patients tested at higher rates than did lower risk patients.
Defaults have been “understudied in medicine,” the researchers say. The study not only reaffirms that behavioral economics “nudges” work, but also that “small interventions can have significant effects.” Moreover, the finding that moving from opt-in to opt-out testing influenced behavior more than even the largest incentive reinforces the notion that “medicine is not just a transaction, and what we say to patients matters.”
Source:
Montoy JCC, Dow WH, Kaplan BC. PLoS One. 2018;13(7):e0199833.
doi: 10.1371/journal.pone.0199833.