Does medical insurance contribute to socioeconomic differentials in health?

Both access to insurance and health itself vary widely by socioeconomic status (SES). Are socioeconomic variations in health linked to insurance coverage or to factors that lie outside the medical care arena? Data from the Aging, Status, and the Sense of Control Survey were the basis of a representative U.S. national telephone survey conducted in 1995, and again in 1998. The results showed that persons with private insurance do not differ significantly from the uninsured in their self-reported health, physical functioning, or number of chronic conditions, whereas persons with public insurance report significantly worse health and more chronic conditions than the uninsured. These longitudinal results hold with adjustment for baseline health, SES, change in social status, and the hazard of attrition. Medical insurance does not mediate any associations between SES and health. Medical insurance of all kinds, however, does reduce difficulties in paying medical bills, and Medicaid is associated with more doctor visits and prescription drugs.