Intervening and reducing sharing of false cancer treatments on social media: Online experiment

Background: Cancer treatment misinformation (e.g., false cures) is shared widely on social media and harmful. Cancer treatment misinformation is potentially shared because people want to help or provide hope for those with cancer. We need strategies, like prompts that inform others that a post may be false, to redirect individuals to prosocially intervene instead of sharing to reduce cancer treatment misinformation. Objective: We examined whether social cue prompts with a post review policy would lead to more intervening and less sharing of cancer treatment misinformation. Methods: We conducted a between-persons online experiment with adult participants from the US recruited via Prolific. Participants were randomized to view cancer treatment misinformation social media posts with social cue prompts and a flagging policy (treatment) or no prompts or policy (control) and reported willingness for intervening (e.g., flagging), sharing, and message reactions. Participants also reported their motivations for intervening or sharing the posts. Results: Social cue prompts and policies for platform action encouraged participants to intervene (e.g., flag) significantly more than people who did not see prompts, p