“I Respect Whatever Decision You Make!” How Autonomy Support and Exemplars in Short-Form Videos Influence Clinical Trial Recruitment

This study was designed to test two message features (autonomy support and evidence type) found in clinical trial recruitment videos on social media. Using an online experiment in which 606 individuals watched short-form videos about clinical trials, we assessed the impact of varying autonomy support conditions (supportive vs. non-supportive) and incorporating exemplars of a previous clinical trial participant's experience (vs. base-rate information about participating). The findings show that communicating about clinical trials with an autonomy-supportive approach can reduce psychological reactance and improve perceived message effectiveness, attitudes toward clinical trial participation, intentions to engage with the content (i.e., "liking" and sharing the content), and intentions to participate in clinical trials. When combined with an exemplar, autonomy-supportive messaging can be especially effective at reducing psychological reactance and improving attitudes toward clinical trials. The findings are well-timed, as researchers are increasingly turning to social media to enhance clinical trial recruitment.