An exploration of participants' treatment preferences in a partial RCT

The partial RCT is a modified design meant to account for participants' treatment preferences. Little is known about the factors that influence such preferences. This study investigated the extent to which participants are willing to be randomized and the factors that affect their treatment preferences. The quantitative and qualitative data collected as part of a partial RCT evaluating 2 behavioural interventions for insomnia were analyzed. Of the participants, 75% were unwilling to be randomly allocated to a treatment group. This figure increased to 90% after information on the 2 interventions was provided. Participants' knowledge of the treatment, its suitability, and their perceived ability to adhere to it influenced their treatment preference. A few participants who had no strong preference and who required treatment were willing to be randomized. The findings raise questions about the impact of treatment preference and allocation procedures on the validity of study conclusions.