Participant perspectives about decentralised trial procedures in a remote delivery nutrition intervention trial.

Participant recruitment and retention are consistently recognised as significant, costly challenges in nutrition intervention trials. Decentralised study procedures address some of the recruitment and retention limitations in traditional trial methodology. Understanding participant perceptions and experiences of decentralised methods in nutrition studies is key to improving trial design and conduct. The aim of this study was to explore participant opinions about remote delivery of a dietary supplement intervention trial. Adults enrolled in a clinical trial of a milk fat globule membrane nutritional supplement for improvement of psychological wellbeing were invited to take part in a post-intervention interview. Interviews were conducted over video conferencing and transcribed. Using a semi-structured interview format six aspects of trial design were discussed: general processes, written instructions, contact throughout the study, self-collection of saliva samples, wearable device use, and cognitive assessment. Thematic analysis derived themes from the data for each of the aspects of trial conduct discussed. Seventy-three participants completed the interview. Interviewees reported a positive overall experience of the remote delivery procedures used. Accessible communication between researchers and participants and clear written instructions were identified as key to participant experience. Recall of instructions and adherence to the nutritional intervention was difficult for some respondents with suggestions made for facilitating this in future remote delivery nutrition studies. Use of wearables, in-home saliva sampling, and self-administered cognitive assessments were feasible and acceptable to most participants. The remote delivery of a nutritional intervention trial, including self-collected biological samples, is feasible and positively viewed by participants.