Reactance to Social Authority in Entertainment-Education Media: Protocol for a Web-Based Randomized Controlled Trial.

Background: Entertainment-education media can be an effective strategy for influencing health behaviors. To improve entertainment-education effectiveness, we seek to investigate whether the social authority of a person delivering a health message arouses the motivation to reject that message-a phenomenon known as reactance.

Objective: In this study, using a short animated video, we aim to measure reactance to a sugar reduction message narrated by a child (low social authority), the child's mother (equivalent social authority to the target audience), and a family physician (high social authority). The aims of the study are to determine the effect of the narrator's perceived social authority on reactance to the sugar reduction message, establish the effectiveness of the video in improving behavioral intent to reduce the intake of added sugars, and quantify participants' interest in watching the entertainment-education intervention video.

Methods: This is a parallel group, randomized controlled trial comparing an intervention video narrated by a low, equivalent, or high social authority against a content placebo video and a placebo video. Using a web-based recruitment platform, we plan to enroll 4000 participants aged between 18 and 59 years who speak English and reside in the United Kingdom. The primary end points will include measures of the antecedents to reactance (proneness to reactance and threat level of the message), its components (anger and negative cognition), and attitudinal and behavioral intent toward sugar intake. We will measure behavioral intent using list experiments. Participants randomized to the placebo videos will be given a choice to watch one of the sugar-intervention videos at the end of the study to assess participant engagement with the entertainment-education video.

Results: The study was approved by the ethics committee of Heidelberg University on March 18, 2020 (S-088/2020). Participant recruitment and data collection were completed in December 2020. The data analysis was completed in April 2021, and the final results are planned to be published by August 2021.

Conclusions: In this trial, we will use several randomization procedures, list experimentation methods, and new web-based technologies to investigate the effect of perceived social authority on reactance to a message about reducing sugar intake. Our results will inform the design of future entertainment-education videos for public health promotion needs.

Trial Registration: German Clinical Trials Registry DRKS00022340: https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00022340.

International Registered Report Identifier (irrid): DERR1-10.2196/25343.