As corporate wellness programs have increased inpopularity, so has the scrutiny and criticism of policies thatreward employees for taking measures to become healthier.

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Privacy advocates have raised concerns about workers beingforced to share personal information with their employers as wellas with third party companies that are hired to conduct thewellness programs, while some experts have suggested that wellnessprograms are mostly for show, and don't ultimately save employersmuch money on health care.

A recent study conducted by researchers at theUniversity of Pennsylvania appears to affirm the latter criticism.A study of 197 obese employees taking part in a wellness programshowed no significant weight loss among the participants. Theworkers were were divided into four groups, one of which receivedno financial incentive to lose weight, two of which were offeredreduced insurance premiums and one of which got to participate in adaily lottery as a reward.

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After a year, none of the groups showed significant weight loss.The researchers concluded that the $550 in incentives that thepremium reductions and lottery prizes represented may not have beenenough to inspire employees to lose weight. The lottery policyrequired workers to do daily weigh-ins at the workplace, whichmight have discouraged some participants.

“That made sustained engagement and behavior change morechallenging,” Dr. Kevin Volpp, director of the Penn Center forHealth Incentives and Behavioral Economics, said in a universitypress release.

Another researcher, Mitesh Patel, an assistant professor ofmedicine and health care management, said that modest premiumadjustments might also not be enough to motivate sustained behaviorchanges.

“(T)hese incentives are often delayed and, even when theyaren't, they are typically hidden in paychecks along with otherdeductions and payments,” he said.

The researchers haven't lost hope for all incentives, however.They say the emphasis should be less on size and more on design ofthe incentives. So far, however, they don't have specifics on whatthe ideal incentive would look like.