The physicAl aCtivity Counselling for young adult cancEr SurvivorS (ACCESS) trial: A protocol for a parallel, two-arm pilot randomized controlled trial

Young adults aged 18-39 years commonly experience persistent side effects following cancer treatment that can impair their quality of life. Physical activity (PA) holds promise as a behavioral intervention to mitigate persistent side effects and improve quality of life. Yet, few young adults are active enough to incur these benefits and efforts to promote PA after cancer treatment ends are lacking. Therefore, we developed a novel theory-driven behavior change intervention to promote PA via videoconferencing technology in young adults who have completed cancer treatment, and are undertaking a pilot randomized controlled trial (RCT) to gather evidence to inform the design of a large, full-scale RCT. The specific aims of this parallel, two-arm pilot RCT are to: (1) assess intervention and trial protocol feasibility and acceptability; and (2) generate data on PA behavior. To promote transparency, improve reproducibility, and serve as a reference for forthcoming publication of results, we present the study protocol for this pilot RCT (version 7) within this paper.Young adults who have completed cancer treatment are being recruited from across Canada. After informed consent is obtained and baseline assessments are completed, participants are randomized to the intervention group (i.e., a 12-week behavior change intervention delivered via videoconferencing technology by trained PA counsellors) or usual care group (i.e., no intervention). Several feasibility outcomes covering enrollment, allocation, follow-up, and analysis are tracked by study staff. Acceptability is assessed through interviews exploring participants' experiences, thoughts, and perspectives of the trial protocol (i.e., intervention and usual care groups), as well as participants' views of the intervention and its mode of delivery (i.e., intervention group only) and PA counsellors' experiences delivering the intervention. PA behavior is measured using accelerometers at baseline (pre-randomization), post-intervention, and at follow-up (24 weeks post-baseline).There are growing calls to develop interventions to support young adults' motivation to engage in PA and adopt an active lifestyle to improve their quality of life after cancer treatment ends. Real-time videoconferencing shows promise for disseminating behavior change interventions to young adults and addressing participation barriers. Considering the importance of establishing intervention and trial protocol feasibility and acceptability prior to evaluating intervention efficacy (or effectiveness), this pilot RCT is critical to understand how participants embrace, engage with, and complete the intervention and trial protocol. Indeed, these data will help to determine which refinements, if any, are required to the intervention and trial protocol (e.g., implementation approach, evaluation methods) prior to a large, full-scale RCT aiming to test the effects of the intervention on PA behavior. Additionally, the PA behavior data collected will be useful to inform the sample size calculation for a large, full-scale RCT.The trial was registered with the ClinicalTrials.gov database (ID: NCT04163042) on November 14, 2019, prior to the start of the trial in February, 2021.