reports

Risk adjustment in competitive health plan markets

In: Culyer AJ, Newhouse JP, ed. Handbook of Health Economics, Volume 1. Amsterdam, Netherlands: Elsevier Science B. V.:755-845.

Erasmus University, Rotterdam, Netherlands; Boston University, Boston, MA, USA

In the 1990s many countries have chosen to use prospective payment arrangements for health plans (e.g., health insurers, sickness funds or HMOs) together with health plan competition, as a means of creating incentives to be cost conscious, while preserving quality, innovation and responsiveness to consumer preferences. Risk adjustment is an important mechanism for attenuating problems that threaten the effectiveness of this strategy for resource allocation in health care. Without adequate risk adjustment, competing health plans have incentives to avoid individuals with predictable losses and to select predictably profitable members. This selection and the resulting risk segmentation can have adverse effects in terms of access to care, quality of care and efficiency in the production of care.

This chapter first provides a conceptual framework for thinking about risk adjustment. Second, it gives an overview of the progress developing risk adjustment models in recent years. Third, several forms of risk sharing are discussed, which can be used as a tool for reducing selection in case of imperfect risk adjustment. Fourth, an overview is given of the current practice of risk adjustment and risk sharing in 11 countries. Finally some directions for future research are discussed.