Abstract
PURPOSE: To examine the feasibility of conducting a randomized controlled trial investigating the effectiveness of financial incentives for exercise self-monitoring in cardiac rehabilitation (CR).
METHODS: A 12-week, 2 parallel-arm, single-blind feasibility study design was employed. A volunteer sample of CR program graduates was randomly assigned to an exercise self-monitoring intervention only (control; n = 14; mean age +/- SD, 62.7 +/- 14.6 years), or an exercise self-monitoring plus incentives approach (incentive; n = 13; mean age +/- SD, 63.6 +/- 11.8 years). Control group participants received a "home-based" exercise self-monitoring program following CR program completion (exercise diaries could be submitted online or by mail). Incentive group participants received the "home-based" program, plus voucher-based incentives for exercise diary submissions ($2 per day). A range of feasibility outcomes is presented, including recruitment and retention rates, and intervention acceptability. Data for the proposed primary outcome of a definitive trial, aerobic fitness, are also reported.
RESULTS: Seventy-four CR graduates were potentially eligible to participate, 27 were enrolled (36.5% recruitment rate; twice the expected rate), and 5 were lost to followup (80% retention). Intervention acceptability was high with three-quarters of participants indicating that they would likely sign up for an incentive program at baseline. While group differences in exercise self-monitoring (the incentive "target") were not observed, modest but nonsignificant changes in aerobic fitness were noted with fitness increasing by 0.23 mL[middle dot]kg-1[middle dot]min-1 among incentive participants and decreasing by 0.68 mL[middle dot]kg-1[middle dot]min-1 among controls.
CONCLUSION: This preliminary study demonstrates the feasibility of studying incentives in a CR context, and the potential for incentives to be readily accepted in the broader context of the Canadian health care system.