Research Flaws and Poor Outcomes for Employer Weight Wellness Programs

January 30th, 2013 by MorganDowney Leave a reply »

One of the criteria for a mandatory health contingent wellness program is that it “must be reasonably designed to promote health or prevent disease. For this purpose, it must have a reasonable chance of improving health or preventing disease, not be overly burdensome, not be a subterfuge for discriminating based on a health factor and not be highly suspect in method.”

It would be one thing if there were evidence that employer ‘wellness’ programs for weight management had a “reasonable chance of improving health or preventing disease”.  They do not.

Methodological Flaws

Financial incentives for weight loss have been studied for 30 years. Independent reviewers of the literature have found methodological flaws in many studies, including small sample size, few with a randomized controlled trial design, do not report attrition, short follow-up periods, selection bias, and publication bias. Furthermore, studies have not clearly distinguished voluntary, participatory programs and mandatory health-contingent wellness plans.

According to a recent posting, “The studies proclaiming wellness program success are subject to more than the usual set of limitations, because by definition there is no “intent to treat” control. Almost invariably, all voluntary participants are in one group and those who didn’t want to participate compromise the control, or else the control is a passive matched control on paper, with no indication of whether the control group consists largely of motivated or unmotivated people. In both cases, only motivated participants are included in the study group. This limitation is especially problematic in wellness, because, unlike a drug trial, motivation is by far the most important factor in success in wellness, which is basically an incentivized self-help program.  This critical flaw in the analytic framework produces the anomaly that virtually every desirable wellness outcome is found in voluntary participants only. This aberration permeates not only the peer-review literature, but also the claims made generally by wellness vendors and their corporate customers.” Health Affairs Blog, Al Lewis and Vik Khanna, Is It Time to Re-Examine Workplace Wellness ‘Get Well Quick Schemes, Jan. 16, 2013.

So, we cannot assume that marginally positive outcomes from studies in voluntary, participatory plans can be applied to mandatory, health-contingent plans.

Outcomes by systematic reviews, meta-analyses, selected studies

  • A review of worksite wellness programs by Rand researchers reported on 12 of 33 studies which evaluated physiological markers such as Body Mass Index, cholesterol levels, and blood pressure. Six of these found improvements in 1 or more outcomes, including BMI or weight, diastolic blood pressure and body fat mass. Effects included decreases in BMI by 0.04 kg/m2 among program participants, 4.3% reduction in BMI, and a 1% reduction of diastolic blood pressure. Of these 6 studies, 3 used a randomized clinical trial (RCT) design and 3 used a non-experimental comparison group or an observational design. None of the RCT studies showing a positive effect had a sample size larger than 100. Of the 6 studies not reporting a positive impact, 3 were RCTs and 3 were observational studies. The authors state, “While most studies found improved outcomes, our results confirm the concern that programs are often not evaluated with strong research designs. When evaluations use observational designs, positive effects were found for three-fourths of the outcomes, whereas positive effects were found for only about half of the outcome evaluated with RCTs. Without an RCT design a causal effect between the programs and outcome cannot be drawn reliably, and nonexperimental designs are more prone to selection bias. Additional limitations of these studies include small sample sizes and short follow-up periods. Only 2 studies had more than 120,000 participants, while others had as few as 50 to 200 participants. Follow-up was 2 years or less for 70% of the studies, and studies with shorter follow-up tended to show more positive results…Use of self-reported findings in 21 of the 33 studies may also impact the validity, especially if participants were aware of program assignment. Typical incentive amounts were small and below the level authorized by the HIPAA Nondiscrimination Requirements. Osilla KC, et al Systematic Review of the Impact of worksite wellness programs. Am J Manag Care 2012 Feb 1:18(2); e68-81.

    • A paper released by the Department of Labor with the proposed regulations assessed wellness marketplace focusing on diet, “Diet was another commonly targeted health behavior. Twelve studies evaluated diet, and six (50%) found significant improvements including higher fruit and vegetable consumption and lower fat and energy intake. Programs consisted of group- and individual-level counseling, web-based self-help programs, and access to farmers markets and health expos. Overall, effects were typically small to moderate, such as consumption of an average of 0.2 fewer fast food meals per week, reduction of fat intake by 3 grams (from 51 to 48.1 grams) per day, or an increase of 0.7 servings (from 2.9 to 3.6 servings) of fruits and vegetables per day.” Regarding physiological markers such as BMI, the authors found, “Programs were multifaceted offering virtual support for activity logging, telephone support from health professionals, and health education materials…Six of these studies found beneficial effects in one or more outcomes, including BMI or weight, diastolic blood pressure, and body fat. Three studies found that participants showed a modest decrease in weight of 0.8 kg or BMI of 0.14kg/m2, while nonparticipants showed slight increase in weight of 0.6kg and BMI or 0.42kg/m2. Though the magnitude between the groups is small, wellness programs may help reverse weight gain over time.” The study noted returns on investment of workplace programs have been declining from around 6 to 1 in a 2005 study to around 3.1 today. “In any case, the expectations of very high cost savings may not materialize.” Mattke S, Schnyer C, Van Busum KR, A Review of the U.S. Workplace Wellness Market. Click here.

  • A 2011 meta-analysis of workplace physical activity and dietary behavior looked at weight outcomes in 22 studies. They found that the majority of studies had only fair or poor quality. They found that there was moderate quality evidence of physical activity and dietary behavior interventions resulting in only a loss of 1.9 kg. They found moderate quality evidence that such interventions reduced BMI by only 0.34 kg/m2. Verweij LM, Coffeng J, van Mechelen W, Proper KI, Meta-analysis of workplace physical activity and dietary behavior interventions on weigh outcomes. Obes Reviews 2011;12:406-429.

  • A review of 33 European studies of workplace physical activity interventions found no or inconclusive evidence for obesity-related outcomes in all intervention categories. Study designs for external validity were poor.  Vuillemin A, et al, Worksite physical activity interventions and obesity: a review of European studies (the HOPE project.) Obes Facts, 2011;4(6):470-88

  • A 2009 systematic review by the Task Force on Community Preventive Services of the CC found employer wellness program showed a very modest benefit of just 2.8 pounds weight loss over controls at 12 months. It is not known if such programs were mandatory health-contingent plans or voluntary participatory plans. Anderson LM, et al, The Effectiveness of Worksite Nutrition and Physical Activity Interventions for Controlling Employee Overweight and Obesity: A Systematic Review Am J Prev Med 2009 Oct;37(4):340-357.

  • A 2011 meta-analysis looked at interventions promoting physical activity among obese populations. The 46 interventions studied did have an effect on the subject’s levels of physical activity. However, there was large variability in efficacy among interventions. There were also relatively low numbers of participants in the studies, indicating that the samples were not necessarily representative of the obese population. Gourlan MJ, Trouilloud, DO, Sarrazin PG, Interventions promoting physical activity among obese populations: a meta-analysis considering global effect, long-term maintenance, physical activity indicators and dose characteristics. Obes Rev 2011 Jul:12(7):e633-45.

  • A report by BlueCross Blue Shield of Kansas City on results in 15 employer groups with 9,637 participants indicated some improvements in blood pressure control and total cholesterol but no improvements in weight control. Hochart C, Lang M, Impact of comprehensive worksite wellness program on health risk, utilization, and health care costs, Popul Health Manag 2011 Jun:14(3):111-6.

  • A 2007 review of randomized clinical trials involving financial incentives in the treatment of overweight and obesity found the maximum attrition in any such study was 57.9% at 13 months. Meta-analysis found no significant effect of use of financial incentives on weight loss or maintenance at 12 months and 18 months. Paul-Ebhohimhen, V, Avenell, A, Systematic Review of the Use of Financial Incentives in Treatments for Obesity and Overweight Obes Rev 2008 Jul;9(4):355-67.

  • A 2009 study analyzed data on 2,407 employees in 17 worksites who participated in a year-long worksite health promotion program that offered financial rewards for weight loss. In some cases, employees posted a bond that would be refunded at year’s end conditional on achieving certain weight loss goals. Others received no financial incentives at all and served as a control group. The investigators found that weight loss is modest; at one year is averages 1.4 pounds for those paid steady quarterly rewards and 3.6 pounds for those who posted a refundable bond. Year-end attrition was as high as 76.4%, far higher than that for other weight loss interventions, such as drug studies. Even those in the control group which received $20 a quarter for just being weighed had a drop-out rate of 48% by the last quarter. The average weight loss in the standard incentives group was 2.2 pounds. There were some impressive success stories of significant weight loss and there were also instances of weight gain in the program. Interestingly, there was a greater percentage of the control group reaching 5% weight loss than in the standard incentives group. The percentage for reaching 10% weight loss was similar (around 2.5%) for the control group, standard intervention and the modified incentives group. NIH considers a loss of 10% of baseline weight in 6 months to one year to be good progress for obese individuals.

Cawley, J, Price JA, Outcomes in a Program that Offers Financial Rewards for Weight Loss, NBER Working Paper No. 14987, May 2009.

  • A recent study from Germany did find significant weight loss, 2.6% and 2.9% higher in  the intervention groups compared to controls. The incentivized group reached 5% weight loss. However, as with many such studies, the study period was too short to capture the probability of regain. Augurszky, B, et al, Does Money Burn Fat? Evidence from a Randomized Experiment, IZA, Sept. 2012. (Germany)

So, contrary to the preamble’s language that insufficient evidence exists to justify the regulation, the fact is that there are numerous studies, systematic reviews and meta-analysis to indicate that these programs do not work to produce anything other than very small, clinically insignificant amounts of weight loss.

Furthermore, financial incentives may have adverse effects. In one study, financial incentives were contingent upon meeting behavioral goals for 3 weeks and became contingent upon merely providing data during the 4-5 month maintenance period. Financial motivation predicted a steeper rate of weight regain during the maintenance period. Financial motivation and gender reacted significantly; men had a more deleterious influence from financial motivation than women. Moller AC, McFadden HG, Hedeker D, Spring B, Financial Motivation Undermines Maintenance in an Intensive Diet and Activity Intervention, J of Obesity, 2012;2012:740519.


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