Behavioral Interventions for Promoting Preventive Health: The Role of Trust

Abstract: Behavioral interventions, such as nudges and reminders, often aim to prompt actions aligned with individuals' long-term interests. However, their success hinges on how recipients perceive the intentions behind these messages. Across four studies, we investigated how providing justifications for urgent interventions impacts trust inferences and intervention effectiveness.

In partnership with UCLA Health, two large-scale RCTs (Studies 1a and 1b) tested text message reminders for preventive screenings. Messages emphasizing urgency and forgetfulness reduced engagement in Study 1a but showed no significant effect in Study 1b. In Study 1a, recipients may have interpreted the caution against forgetfulness as an implication of incompetence, inferring that their healthcare provider did not trust them to manage their health. However, in Study 1b, where recipients had already failed to act, the same justification may have been viewed as more appropriate, mitigating distrust inferences. Study 2 demonstrated that inferred distrust mediated the negative impact of justifications, while Study 3 pinpointed justification as the primary trigger of distrust when paired with urgency. These findings highlight the risks of implied mistrust in behavioral interventions.

Keywords: Trust, Nudges, Interventions