Study design
word of mouth
RECRUITMENT, BLIND
A 12-week (April-July 2018), parallel-group, pilot cluster RCT for promoting PA called Columbia Moves was conducted. Participants were recruited (January-April 2018) from the Greater Columbia, South Carolina, U.S.A. area via flyers, e-mails sent via listservs, and word of mouth. Interested individuals were encouraged to form a self-selected team of 3–8 persons comprised of members in their existing social circle (e.g., friends, family members, co-workers). Individuals applied through a study recruitment website and were screened for eligibility by phone. Then, they were invited to an in-person orientation and informed consent was obtained. Following the orientation session, individuals’ PA status was measured via the ActiGraph GT9X Link accelerometer (ActiGraph, Pensacola, FL), serving both as confirmation of eligibility and a baseline measure. Additional baseline assessments occurred at a subsequent visit. Treatment assignment was then communicated to each eligible team of individuals via email and an in-person kickoff meeting was administered to introduce them to their respective intervention. Assessments were conducted immediately after the 12-week intervention and at 40 weeks post-intervention. The assessor was not blind to group allocation, but assessment instructions were standardized, the PA measures were device-based, and survey items were administered online via LimeSurvey, minimizing the risk of assessor bias. Incentives were offered for completing these two assessment periods (drawing for a $50 gift card for one participant per study arm and a $20 gift card for 1 participant per team at 12 weeks, as well as a drawing for 1 $200 gift card, 4 $100 gift cards, and 5 t-shirts valued at $25 across both arms, and $25 gift cards for up to 2 participants per team at 52 weeks). The study was approved by the Institutional Review Board at the University of South Carolina.