Economic evaluation of an incentive-based program to increase physical activity and reduce sedentary behaviour in middle-aged adults

BACKGROUND: Incentive-based programs represent a promising approach for health insurers to encourage health-promoting behaviours. However, little is known about the value for money of such programs. This study aimed to determine the cost-effectiveness of the ACHIEVE (Active CHoices IncEntiVE) program designed to incentivise increased physical activity and reduced sedentary behaviour in middle-aged adults. METHODS: A within-trial cost-efficacy analysis was conducted. Benefits were assessed by evaluating paired t-tests from participants’ pre- and post- trial Body Mass Index (BMI) (kg/m(2)), sitting time (minutes/day) and metabolic equivalents (METS) minutes. A health sector perspective was adopted for the assessment of costs. Pathway analysis was used to determine the resource use associated with the intervention, with costs expressed in Australian dollars (A$) for the 2015 reference year. A long-term cost-effectiveness analysis was undertaken which extended the analysis time horizon and the trial population to the relevant eligible Australian population. Within this analysis, the 16-week intervention was modelled for roll-out across Australia over a 1-year time horizon targeting people with private health insurance who are insufficiently active and highly sedentary. Improved health related quality of life quantified in Health-Adjusted Life Years (HALYs) (based on the health impacts of increased metabolic equivalent (MET) minutes and reduced body mass index (BMI) and cost-offsets (resulting from reductions in obesity and physical inactivity-related diseases) were tracked until the cohort reached age 100 years or death. A 3% discount rate was used and all outcomes were expressed in 2010 values. Simulation modelling techniques were used to present 95% uncertainty intervals around all outputs. RESULTS: The within-trial cost-efficacy analysis indicated that the ACHIEVE intervention cost approximately A$77,432. The cost per participant recruited was A$944. The incremental cost-effectiveness ratio (ICER) for MET increase per person per week was A$0.61; minute of sedentary time reduced per participant per day was A$5.15 and BMI unit loss per participant was A$763. The long-term cost effectiveness analysis indicated that if the intervention was scaled-up to all eligible Australians, approximately 265,095 participants would be recruited to the program at an intervention cost of A$107.4 million. Health care cost savings were A$33.4 million. Total HALYs gained were 2,709. The mean ICER was estimated at A$27,297 per HALY gained which is considered cost-effective in the Australian setting. CONCLUSION: The study findings suggest that financial incentives to promote physical activity and reduce sedentary behaviour are likely to be cost-effective. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRN12616000158460 (10/02/2016). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12913-022-08294-7.