Outcomes
RECRUITMENT
The primary outcomes were feasibility, acceptability, and preliminary efficacy of the intervention. Feasibility was assessed through trial uptake, attrition, and engagement. A preregistered target sample of 30 participants was set to meet the aims of the study, with feasibility indicated if this sample size was met within the 6-month recruitment timeframe. Acceptability was assessed with the subscales (range 1-5, with higher scores indicating more positive evaluations) of the Mobile Application Rating Scale–User version [Secondary outcomes were rumination, as measured by the Ruminative Response Scale (RRS) total score (range 22-88, with higher scores indicating greater severity) [