Participant vs. Non-Participant Analysis
The most common method for measuring wellbeing ROI is comparing healthcare costs for program participants vs. non-participants. If participants have lower costs than non-participants, the program appears to be working. But this comparison is confounded by selection bias — employees who choose to participate in wellness programs are typically healthier than those who do not.
Addressing Selection Bias
- Propensity score matching: Match participants to non-participants with similar health profiles
- Difference-in-differences: Compare cost trends before and after program enrollment
- Randomized controlled trials: Randomly assign employees to program vs. control group (gold standard but rarely feasible)
- Regression analysis: Control for demographic and health factors in cost comparisons
- Pre-post analysis: Compare participant costs before and after enrollment
Trend Analysis
IQ Insight
Trend analysis — comparing cost trends for participants vs. non-participants over 3–5 years — is more robust than point-in-time comparisons. If participants' costs are growing at 3% per year while non-participants' costs are growing at 8% per year, the program is delivering value even if participants' absolute costs are higher (due to selection bias). Trend analysis is the most credible method for demonstrating long-term wellbeing ROI.