Effectiveness and Ethics of Incentives for Research Participation: 2 Randomized Clinical Trials.

Area of Science:

• Clinical Trials and Research Ethics
• Health Services Research
• Behavioral Economics in Healthcare

Background:

• Financial incentives for research participation are controversial due to concerns about undue or unjust inducement.
• Uncertainty exists regarding whether incentives diminish risk sensitivity or disproportionately enroll underserved populations.
• Ethical and regulatory frameworks for research incentives remain variably defined.

Purpose of the Study:

• To determine if financial incentives enhance enrollment in real-world randomized clinical trials (RCTs).
• To assess whether incentives act as undue inducements, affecting risk perception.
• To evaluate if incentives function as unjust inducements, impacting enrollment of specific socioeconomic groups.

Main Methods:

• Two embedded randomized clinical trials (RCTs) were conducted within larger parent RCTs (smoking cessation and ambulation interventions).
• Participants were randomized to receive different incentive amounts ($0, $200, $500 for smoking cessation; $0, $100, $300 for ambulation).
• Primary outcomes measured consent rates, with secondary outcomes assessing risk perception, understanding, and coercion.

Main Results:

• Incentives significantly increased consent rates in the smoking cessation trial (P < .001).
• Incentives did not significantly increase consent rates in the ambulation trial (P = .45).
• No evidence of undue or unjust inducement was found in either trial across various incentive levels.

Conclusions:

• Financial incentives can effectively increase trial enrollment in specific contexts.
• The study provides evidence that incentives, when appropriately designed, do not necessarily lead to undue or unjust inducement.
• Findings support the ethical use of financial incentives to improve research participation rates.