The Impact of Nearly Universal Insurance Coverage on Health Care Utilization: Evidence from Medicare.

The onset of Medicare eligibility at age 65 leads to sharp changes in the health insurance coverage of the U.S. population. These changes lead to increases in the use of medical services, with a pattern of gains across socioeconomic groups that varies by type of service. While routine doctor visits increase more for groups that previously lacked insurance, hospital admissions for relatively expensive procedures like bypass surgery and joint replacement increase more for previously insured groups that are more likely to have supplementary coverage after 65, reflecting the relative generosity of their combined insurance package under Medicare.