The role of health practices in HMO selection bias: a confirmatory study

This research examines the relation between employees' health practices and health plan selection. A previous study, limited to one firm, showed that employees choosing a health maintenance organization (HMO) and a fee-for-service (FFS) plan had similar health practices. We extend this inquiry to 17 Minneapolis employees, all of whom offer at least one FFS plan and one or more of the 6 Twin Cities HMOs. Health practices were measured by cigarette smoking, heavy drinking (or abstinence from drinking), use of seat belts, and exercise. We estimated health plan choice equations that show that employees with poor health practices do not systematically prefer FFS plans compared with independent practice associations (IPAs). Nor do they select FFS or IPA plans compared with HMOs on the basis of health habits. We suggest that HMOs do not gain long-term cost advantages by enrolling employees with favorable health practices.