Using global ratings of health plans to improve the quality of health care

Global ratings, such as those based on consumer satisfaction, are a commonly used form of report on the performance of health plans and providers. A simple averaging of the global rating by plan members leads to a problem: it gives a plan greater incentives to improve services used by low-cost members than services used by high-cost members. This paper presents a formal model of consumer formation of global ratings and the incentives these rating convey to plans. We use this model to characterize weights on consumer respondents to correct the incentive problem. We implement our proposed solution using data from the Consumer Assessments of Health Care Providers and Systems (CAHPS) and the Medicare Current Beneficiary Survey (MCBS). Our correction is low-cost, easily implemented on an on-going basis, and insensitive to assumptions about why health plans care about quality ratings.