Program in Health Services and Systems Research, Duke-NUS Medical School, 8 College Road, Level 4 169857, Singapore; Duke Global Health Institute, Duke University, 310 Trent Drive, Durham NC 27710, United States.
Department of Endocrinology, Obesity & Metabolic Unit, Singapore General Hospital, Outram Road 169608, Singapore.
Soc Sci Med. 2017 Jul;185:63-70. doi: 10.1016/j.socscimed.2017.05.030. Epub 2017 May 15.
The prevalence of overweight and obesity has more than doubled in the past three decades, leading to rising rates of non-communicable diseases. This study tests whether adding a payment/rewards (term reward) program to an existing evidence-based weight loss program can increase weight loss and weight loss maintenance. We conducted a parallel-group randomized controlled trial from October 2012 to October 2015 with 161 overweight or obese individuals randomized to either control or reward arm in a 1:2 ratio. Control and reward arm participants received a four month weight loss program at the LIFE (Lifestyle Improvement and Fitness Enhancement) Centre at Singapore General Hospital. Those in the reward arm paid a fee of S$165.00 (1US$ = 1.35S$) to access a program that provided rewards of up to S$660 for meeting weight loss and physical activity goals. Participants could choose to receive rewards as guaranteed cash payments or a lottery ticket with a 1 in 10 chance of winning but with the same expected value. The primary outcome was weight loss at months 4, 8, and 12. 161 participants were randomized to control (n = 54) or reward (n = 107) arms. Average weight loss was more than twice as great in the reward arm compared to the control arm at month 4 when the program concluded (3.4 kg vs 1.4 kg, p < 0.01), month 8 when rewards concluded (3.3 kg vs 1.8 kg, p < 0.05), and at month 12 (2.3 kg vs 0.8 kg, p < 0.05). These results reveal that a payment/rewards program can be used to improve weight loss and weight loss maintenance when combined with an evidence-based weight loss program. Future efforts should attempt to replicate this approach and identify how to cost effectively expand these programs to maximize their reach. This study is registered at www.clinicaltrials.gov (Identifier: NCT01533454).
超重和肥胖的患病率在过去三十年中增加了一倍多，导致非传染性疾病发病率上升。本研究旨在测试在现有的基于证据的减肥计划中加入支付/奖励（定期奖励）计划是否可以增加减肥和减肥维持的效果。我们于 2012 年 10 月至 2015 年 10 月进行了一项平行组随机对照试验，将 161 名超重或肥胖个体随机分为对照组或奖励组，比例为 1:2。对照组和奖励组的参与者在新加坡总医院的 LIFE（生活方式改善和健身增强）中心接受为期四个月的减肥计划。奖励组的参与者需支付 165 新元（1 美元=1.35 新元）以获得一项计划，该计划为达到减肥和身体活动目标提供高达 660 新元的奖励。参与者可以选择以保证现金支付或彩票的形式获得奖励，中奖概率为 1/10，但预期价值相同。主要结局是在第 4、8 和 12 个月的体重减轻情况。161 名参与者被随机分配至对照组（n=54）或奖励组（n=107）。当计划结束时（4 个月），奖励组的平均减重明显大于对照组（3.4 千克 vs 1.4 千克，p<0.01），当奖励结束时（8 个月）（3.3 千克 vs 1.8 千克，p<0.05），以及在第 12 个月（2.3 千克 vs 0.8 千克，p<0.05）。这些结果表明，当与基于证据的减肥计划结合使用时，支付/奖励计划可以用于改善减肥和减肥维持效果。未来的研究应该尝试复制这种方法，并确定如何以具有成本效益的方式扩大这些计划，以最大限度地扩大其覆盖面。本研究在 www.clinicaltrials.gov 注册（标识符：NCT01533454）。
