Acceptability and effectiveness of a study information video in improving the research consent process for youth: a non-inferiority trial.

Introduction: Obtaining informed consent for research includes the use of information sheets, which are often long and may be difficult for participants to understand. We conducted a trial to investigate whether consent procedures using a study information video coupled with electronic consent were non-inferior to standard consent procedures using participant information sheets (PIS) among youth aged 18-24 years in Zimbabwe.

Methods: The trial was nested within an endline population-based survey for a cluster-randomised trial from October 2021 to June 2022. Randomisation of participants to video or paper-based consent was at household level. We assessed non-inferiority in comprehension of the study using a questionnaire. The video method was accepted as non-inferior to standard consent procedures if the 95% CIs of the mean difference did not fall below the prespecified margin of 1.98. Thematic analysis was conducted on brief qualitative discussions with randomly selected youth to explore the acceptability of video and PIS within consent methods.

Results: Overall, 921 participants were enrolled (54% female). The median age was 20 (IQR 18-24) years. The mean comprehension score was 25.4/30 in both arms. The mean difference in comprehension between arms was -0.02 (95% CI -0.51 to 0.47) showing non-inferiority of the intervention in comprehension of study information. Youth (N=90) described both consent methods as interactive and inclusive. Those in the video consent arm felt it was exciting and youth focused. The use of imagery to explain procedures strengthened the perceived trustworthiness of the research. However, the high volume of information in both arms reduced acceptability.

Conclusion: Comprehension of study information using an information video is non-inferior to a paper-based consent method. Using information videos for consent processes shows promise as a person-centred and context-sensitive approach to enhance the informed consent process and should be encouraged by ethics committees.