Individual Versus Team-Based Financial Incentives to Increase Physical Activity: A Randomized, Controlled Trial.

BACKGROUND: More than half of adults in the United States do not attain the minimum recommended level of physical activity to achieve health benefits. The optimal design of financial incentives to promote physical activity is unknown. OBJECTIVE: To compare the effectiveness of individual versus team-based financial incentives to increase physical activity. DESIGN: Randomized, controlled trial comparing three interventions to control. PARTICIPANTS: Three hundred and four adult employees from an organization in Philadelphia formed 76 four-member teams. INTERVENTIONS: All participants received daily feedback on performance towards achieving a daily 7000 step goal during the intervention (weeks 1- 13) and follow-up (weeks 14- 26) periods. The control arm received no other intervention. In the three financial incentive arms, drawings were held in which one team was selected as the winner every other day during the 13-week intervention. A participant on a winning team was eligible as follows: $50 if he or she met the goal (individual incentive), $50 only if all four team members met the goal (team incentive), or $20 if he or she met the goal individually and $10 more for each of three teammates that also met the goal (combined incentive). MAIN MEASURES: Mean proportion of participant-days achieving the 7000 step goal during the intervention. KEY RESULTS: Compared to the control group during the intervention period, the mean proportion achieving the 7000 step goal was significantly greater for the combined incentive (0.35 vs. 0.18, difference: 0.17, 95 % confidence interval [CI]: 0.07-0.28, p <0.001) but not for the individual incentive (0.25 vs 0.18, difference: 0.08, 95 % CI: -0.02-0.18, p = 0.13) or the team incentive (0.17 vs 0.18, difference: -0.003, 95 % CI: -0.11-0.10, p = 0.96). The combined incentive arm participants also achieved the goal at significantly greater rates than the team incentive (0.35 vs. 0.17, difference: 0.18, 95 % CI: 0.08-0.28, p < 0.001), but not the individual incentive (0.35 vs. 0.25, difference: 0.10, 95 % CI: -0.001-0.19, p = 0.05). Only the combined incentive had greater mean daily steps than control (difference: 1446, 95 % CI: 448-2444, p ≤ 0.005). There were no significant differences between arms during the follow-up period (weeks 14- 26). CONCLUSIONS: Financial incentives rewarded for a combination of individual and team performance were most effective for increasing physical activity. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT02001194.

A Randomized, Controlled Trial of Lottery-Based Financial Incentives to Increase Physical Activity Among Overweight and Obese Adults.

PURPOSE: To evaluate the effect of lottery-based financial incentives in increasing physical activity. DESIGN: Randomized, controlled trial. SETTING: University of Pennsylvania Employees. PARTICIPANTS: A total of 209 adults with body mass index ≥27. INTERVENTIONS: All participants used smartphones to track activity, were given a goal of 7000 steps per day, and received daily feedback on performance for 26 weeks. Participants randomly assigned to 1 of the 3 intervention arms received a financial incentive for 13 weeks and then were followed for 13 weeks without incentives. Daily lottery incentives were designed as a "higher frequency, smaller reward" (1 in 4 chance of winning $5), "jackpot" (1 in 400 chance of winning $500), or "combined lottery" (18% chance of $5 and 1% chance of $50). MEASURES: Mean proportion of participant days step goals were achieved. ANALYSIS: Multivariate regression. RESULTS: During the intervention, the unadjusted mean proportion of participant days that goal was achieved was 0.26 in the control arm, 0.32 in the higher frequency, smaller reward lottery arm, 0.29 in the jackpot arm, and 0.38 in the combined lottery arm. In adjusted models, only the combined lottery arm was significantly greater than control ( P = .01). The jackpot arm had a significant decline of 0.13 ( P < .001) compared to control. There were no significant differences during follow-up. CONCLUSIONS: Combined lottery incentives were most effective in increasing physical activity.

A Randomized Trial of Social Comparison Feedback and Financial Incentives to Increase Physical Activity.

PURPOSE: To compare the effectiveness of different combinations of social comparison feedback and financial incentives to increase physical activity. DESIGN: Randomized trial (Clinicaltrials.gov number, NCT02030080). SETTING: Philadelphia, Pennsylvania. PARTICIPANTS: Two hundred eighty-six adults. INTERVENTIONS: Twenty-six weeks of weekly feedback on team performance compared to the 50th percentile (n = 100) or the 75th percentile (n = 64) and 13 weeks of weekly lottery-based financial incentive plus feedback on team performance compared to the 50th percentile (n = 80) or the 75th percentile (n = 44) followed by 13 weeks of only performance feedback. MEASURES: Mean proportion of participant-days achieving the 7000-step goal during the 13-week intervention. ANALYSIS: Generalized linear mixed models adjusting for repeated measures and clustering by team. RESULTS: Compared to the 75th percentile without incentives during the intervention period, the mean proportion achieving the 7000-step goal was significantly greater for the 50th percentile with incentives group (0.45 vs 0.27, difference: 0.18, 95% confidence interval [CI]: 0.04 to 0.32; P = .012) but not for the 75th percentile with incentives group (0.38 vs 0.27, difference: 0.11, 95% CI: -0.05 to 0.27; P = .19) or the 50th percentile without incentives group (0.30 vs 0.27, difference: 0.03, 95% CI: -0.10 to 0.16; P = .67). CONCLUSION: Social comparison to the 50th percentile with financial incentives was most effective for increasing physical activity.