Lose Weight, Get Paid: Group Incentive Packs a Punch

Marlene Busko

April 01, 2013

Obese employees shed more pounds and reaped bigger cash rewards when they were offered a group incentive vs an individual one in a short, randomized controlled trial.

Weight loss at 6 months, the study's primary outcome, was greater among those in the group-incentive scheme, who lost 3.2 kg (about 7 pounds) more than their peers in the solo scheme. Each of the 2 strategies had the same up-front costs to the employer.

"The key question we are asking here is, 'If we were to allocate the same amount of resources toward incentives [in the group arm] as in the individual-directed arm, might there be more ways we could essentially get more bang for the buck?' " lead author Jeffrey T. Kullgren, MD, from the Veterans Affairs Ann Arbor Healthcare System, Michigan, told Medscape Medical News.

He added that these kinds of strategies "are becoming more frequent in employer settings [and] are really important adjuncts to key work that clinicians continue to do day in, day out, to try to motivate healthy behaviors among our patients."

The study was published April 1 in Annals of Internal Medicine and follows research reported at the American College of Cardiology meeting last month, which showed that employees paid to attend weekly counseling sessions and meet weight-loss goals lost 4 times as much weight as those who were not.

Incentive Schemes Common, but Best Approach Unknown

Dr. Kullgren and colleagues explain that many large employers in the United States offer obese employees incentives to lose weight, but little is known about which approaches work best.

In this study, they enrolled 105 employees of a Philadelphia hospital who were 18 to 70 years old, had a body mass index (BMI) of 30 to 40, and wanted to lose weight. The workers, mostly women, were randomly assigned to group financial incentives, individual financial incentives, or controls.

The participants were referred to the Weight-Control Information Network website of the National Institute of Diabetes and Digestive and Kidney Diseases to find diet and exercise suggestions. They attended monthly weigh-ins and filled in online questionnaires about behavior.

Five anonymous employees made up each group and got a share of $500 per month if they lost the target weight of 0.4 kg per week. For example, if only 1 member attained this weight-loss target, he or she would get $500; if 2 members met the goal, each would get $250. Single employees assigned to the individual strategy would get $100 a month if they lost this amount, and the controls received no cash incentives. The target weight loss for the whole 24 weeks of the intervention was 10.8 kg.

"That's a weight-loss goal I often give my patients—a pound a week over 6 months—a very reasonable target for a BMI over 30 or being in the obese category," Dr. Kullgren said. "Many of these patients have tried [losing weight ] many times before, and they have some idea about what works for them…[but] weight loss is really hard, and the benefits occur in the future," so this program offered tangible, immediate rewards to help them stay on track, he added.

The program was not designed to reward "the biggest loser" at the study end, he noted. Rather, the researchers sought to motivate people by giving them a chance to win cash each month they met their weight-loss goal.

At 6 months, the group-incentive participants had lost the most weight (mean 4.8 kg) and received an average payout of $514, those in the individual-incentive group had lost an average of 1.7 kg and received an average payout of $128, and the control-group participants had lost 0.5 kg.

A sense of competition and the chance to win more than $100 each month may have provided increased motivation with the group-incentive scheme, Dr. Kullgren speculated.

Three months after the monetary rewards had ceased, the employees had regained some of the weight. Compared with the study start, the controls had lost 0.4 kg; individual-incentive participants had lost 0.8 kg, and group-incentive participants 3.4 kg.

'A Powerful Tool, Money Well Spent'

In an accompanying editorial, Jason Riis, PhD, from Harvard Business School, Boston, Massachusetts, says Dr. Kullgren and colleagues "have set the standard for the care and rigor with which such randomized, controlled trials of incentives should be conducted."

"Incentives are a powerful tool to help people lose weight…and there are various ways that these incentives can be structured," he told Medscape Medical News. "We need more studies like this to determine which are the most cost-effective."

Asked if use of these kinds of schemes is money well spent, he said "I think the health effects of a 5% to 10% decline in body weight are quite well documented. Is that worth payouts of a few hundred dollars to employees or citizens? Yeah, probably."

Nevertheless, larger and longer trials would allow for more accurate measurement of incentive effectiveness and cost-effectiveness, he writes. Such trials could also measure possible positive side effects of employee-incentive programs (such as community building) and negative side effects (such as weight stigmatization).

And another important aim is to help change the home and workplace environment, he added. "If temptations are there, we'll eat them."

Dr. Kullgren has disclosed receiving support for travel to meetings for the study or other purposes from the National Institute on Aging, Department of Veterans Affairs, and Robert Wood Johnson Foundation; his institution has received grants from the National Institute on Aging and provision of writing assistance, medicines, equipment, or administrative support from the Department of Veterans Affairs and Robert Wood Johnson Foundation. Disclosures for the coauthors are available online. Dr. Riis has disclosed no relevant financial relationships.

Ann Intern Med 2013;158:505-514, 560-561.