Abstract
BACKGROUND: Physical activity (PA) benefits young adults living with and beyond cancer, yet participation remains low. This pilot randomized controlled trial (RCT) evaluated the feasibility and acceptability of a PA behavior counseling intervention for young adults post-cancer treatment and trial methods. METHODS: A mixed-methods, open-label, parallel, two-arm pilot RCT was conducted with young adults recruited nationwide (Canada) by healthcare provider referral or advertising. Eligible participants were 18-39 years (with a first diagnosis of invasive, non-metastatic cancer at age 18-39 years), had completed active treatment for invasive, non-metastatic cancer < 5 years prior, self-reported < 150 min of moderate-to-vigorous intensity PA weekly, were fluent in English, and had access to/computer literacy for videoconferencing technology. Young adults were randomized to receive a 12-week individualized PA behavior counseling intervention delivered via videoconferencing technology by PA counselors or usual care. Informed by self-determination theory, the intervention emphasized autonomy support and applied motivational interviewing. Staff tracked feasibility and acceptability outcomes regarding enrollment, allocation, retention, adherence, and adverse events. Young adults and PA counselors were interviewed post-intervention (T1; primary endpoint) and at trial completion, respectively. Planned efficacy outcomes were assessed using accelerometers and online surveys at baseline (T0), T1, and follow-up (T2; secondary endpoint; 24 weeks post-baseline). RESULTS: Seventy-four young adults were screened for eligibility (recruitment rate ~ 4/month over 18 months); 47 (63.5%) were eligible, of which 42 (89%) consented, completed T0 assessments, and were randomized. Most (75% [15/20]) allocated to receive the intervention completed all sessions. Retention rates were 85.7% (T0 to T1 [36/42]) and 71.4% (T0 to T2 [30/42]). Analyzable data for the primary efficacy outcome (PA behavior) were available for 57.1% (24/42) at T1. Content analysis of interviews with 35 (80.0%) young adults and both (100.0%) PA counselors yielded three themes reflecting factors that positively impacted intervention acceptability and one theme reflecting factors that negatively impacted the trial methods' acceptability, as well as recommendations to optimize the trial methods and intervention. CONCLUSIONS: The trial methods and intervention were largely feasible and acceptable for young adults post-cancer treatment, although modifications are required to optimize recruitment strategies, enhance retention at follow-up, refine the intervention, and reduce missing data. A full-scale RCT to assess the efficacy of the intervention and estimate concomitant costs is warranted. TRIAL REGISTRATION: ClinicalTrials.gov (ID: NCT04163042). Registered on November 14, 2019.