Modest financial incentives offered over an extended period of time were significantly more likely to encourage sustained participation in a weight-loss program and long-term maintenance of weight loss than an identical program that did not offer financial rewards.
One hundred healthy adult employees or dependents aged 18-63 years with a body mass index between 30 to 39.9 kg/m2 were each assigned to one of four weight loss groups: two with financial incentives and two without.
All participants were given a weight-loss goal of 4 pounds per month, with the goal adjusted based on each month’s weight, up to a predetermined goal weight. Participants were weighed monthly for one year.
Participants in the incentive groups who met their goals received modest payments of $20 per month, while those who failed to meet their goals paid a penalty of $20 into a larger bonus pool. Participants from each incentive group who completed the study over a year were eligible to win a lottery of this pool.
Participants in the financial incentive groups maintained greater participation rates and lost more weight than controls who were not offered incentives. The completion rate for participants in the incentive groups was 62 percent compared to just 26 percent for the non-incentive groups.
Mean weight loss was 9.08 pounds for the combined incentive groups compared to 2.34 pounds for the combined non-incentive groups. The estimated effect of incentives was 6.5 pounds. Even participants who were subject to financial penalties were more likely to continue to participate than those in the groups without financial incentives, possibly because taking this risk also made them eligible to earn rewards.
“Fear of losing money tends to motivate people about two and a half times more than the prospect of gaining the same amount of money, so we intentionally designed the incentives so that participants would have some of their own skin in the game,” said Steven Driver, MD, MPH, resident physician in internal medicine at Mayo Clinic and the study’s lead investigator. “If you reached into your pocket and found a ten dollar bill you would be happy, but you wouldn’t be nearly as emotional as you would be if you expected to pull out a ten dollar bill and instead found a hole in your pocket.”
Source: American College of Cardiology, USA