Background: Universal national health insurance, financed jointly by payroll taxes, subsidies, and individual premiums, commenced in Taiwan in 1995. Coverage expanded from 57% of the population (before the introduction of national health insurance) to 98%. Objective: To assess the role of national health insurance in improving life expectancy and reducing health disparities in Taiwan. Design: A before-and-after comparison of the decade before the introduction of national health insurance (1982 - 1984 to 1992 - 1994) with the decade after (1992 - 1994 to 2002 - 2004). Setting: Taiwan. Patients: All townships(n=358) in Taiwan were ranked according to overall mortality rates before the introduction of national health insurance and then ranked into 10 health class groups in descending order of health (groups 1 [healthiest] to 10 [least healthy]). Measurements: Health improvement (change in life expectancy after the introduction of national health insurance) and health disparity (reduction in the difference in life expectancy between the highest- and lowest-ranked health class groups). Results: After the introduction of national health insurance, life expectancy increased more in health class groups that had higher mortality rates before the introduction of national health insurance and health disparity narrowed, reversing an earlier trend toward widening disparity. The major contributors to the reduction in disparity were relatively larger reductions in death from cardiovascular diseases, ill-defined conditions, infectious diseases, and accidents in the lower-ranked health class groups. However, death from cancer increased more in the lower-ranked health class groups. Utilization of medical services increased, whereas cost remained at 5% to 6% of the gross domestic product. The per capita average annual number of visits to the physician's office was 14. Limitation: The interpretation of comparisons before and after the introduction of national health insurance assumes that the changes were entirely due to the effect of national health insurance rather than secular trends. Conclusion: Life expectancy after the introduction of national health insurance improved more for lower-ranked health classes, resulting in narrowed health disparity. The magnitude of the reduced disparity was small compared with the size of the remaining gaps. Relying on universal insurance alone to eliminate health disparity does not seem realistic. To further reduce health disparity, universal insurance programs should incorporate primary prevention, focusing on lifestyle risk reductions.
