Table 2 A priori feasibility outcome measures

Recruitment

Given that recruitment of older adults for psychology interventions is known to be slow and challenging (Moody et al. 2008), we expected that just 50% of residents who were approached would be interested in participating in the study. We deemed that approaching 40 prospective age-care residents, and recruiting approximately 20 residents (three to four residents per month) over a 6-month recruitment period (July 2018—Jaunary 2019) would be evidence of feasible recruitment.

Acceptability

On completion of the study, participants were asked to indicate their satisfaction. Qualitative feedback from participants was also collected at the conclusion of the final session.

Attrition

An intervention completion rate of ≥ 85% has been deemed acceptable in previous studies of older adults with physical conditions [3]. Therefore, a feasible attrition rate was determined to be 15% or less.

Safety

Behavioural activation is a low-risk intervention, with no known risks. However, any adverse psychological and/or physiological symptoms were recorded at each session. Volunteers were instructed to notify the research coordinator immediately following any adverse events.

Data collection

The research questionnaire was kept very brief, to minimize participant burden. We expected that data collection would not be problematic and that we would have minimal (< 5%) missing data.

Fidelity

The extent to which the volunteer facilitated activity scheduling with their assigned resident was taken as a measure of treatment fidelity. Activity scheduling was measured via volunteer submission of activity scheduling sheets and/or submission of notes outlining activity plans for the week ahead.