SINGAPORE — In a first-of-its-kind study, about 70 people here have forked out almost S$400 each to take part in a weight loss study that could see them each earn up to S$660 — offsetting their deposits and making extra money in the process — if they meet weight loss and exercise goals. Conversely, if they fail to meet any objectives, they will forfeit their deposits.

The study, conducted by the Duke-NUS Graduate Medical School, contrasts with other research studies here where participants usually either volunteer or are paid to take part. So far, it has attracted 110 participants since it began in August 2012. It targets to add another 70 more participants before it concludes next year.

The participants, who all had to pay S$399 to take part in the study, were randomly split into two groups. About a third were put in a controlled group, and were given a refund of S$165. They will be given token sums to commit to the year-long study. The remaining two-thirds were put into the second group. Unlike the first group, they can earn higher sums of money by meeting various objectives over 12 months.

The study’s lead investigator Eric Finkelstein said that behavioural economics showed that getting people to pay a deposit is helpful in motivating them to change behaviours.

“(The study) is to see whether we can increase weight loss with an evidence-based (obesity management) programme by use of incentives and do so in a way that is self-financed by participants,” said Professor Finkelstein, who is from Duke-NUS Graduate Medical School’s Health Services and Systems Research Programme.

Noting that people pay for weight-loss programmes in real world settings, he added: “We also wanted to test whether we could identify an incentive strategy that is self-sustaining, such that the money for incentives comes from participants who are not successful.”

Around the world, monetary incentives have been used to get people to lose weight. For example, the Health Promotion Board is holding a “1 million kg challenge” where participants will win prizes such as shopping vouchers, vacation packages and a car.

Last year, the Dubai government offered its citizens 1g of gold for every kilogramme lost. The United Kingdom had also experimented with a “Pounds for pounds” programme where participants received up to £425 (S$900) for losing weight.

Unlike these, Duke-NUS requires a financial outlay from its participants. Similarly, in a study conducted by the University of Minnesota, researchers would refund participants their US$60 deposit if they manage to lose weight or quit smoking.

Assistant Professor Joanne Yoong from NUS Saw Swee Hock School of Public Health said there have been debates about providing incentives to get people to achieve personal health benefits. But in the long run, a healthier population could be less taxing on the healthcare system, she added.

She said if health policies were to adopt the incentives mechanism together with a deposit portion, as in the Duke-NUS study, this might act as a safeguard against poor outcomes and spur people to commit to their health goals.

Dr Jeremy Lim, head of the Asia-Pacific health and life sciences practice in global consulting firm Oliver Wyman, noted that the National Skin Centre requires patients to pay a S$10 deposit to ensure they turn up for their next appointment. This has helped to reduce the no-show rate, he said.

The findings of the Duke-NUS study could give more insights into behavioural sciences and provide policymakers with more policy design options, he said. Nevertheless, he cautioned against generalising the results across different health conditions.