摘要：Introduction: this study aims 1) to determine the association between individual characteristics before Medicare coverage (pre-Medicare) and the selection into Medicare HMOs (health maintenance organizations) and 2) to quantify the financial impact of Medicare HMO coverage on total and out-of-pocket (OOP) health spending in the first four years of Medicare coverage. Methods: individuals eligible for Medicare because of age in the Health and Retirement Study from 1992 to 2008 were chosen. Individuals interviewed from age 65 to 68 years were included. Pre-Medicare characteristics were used to predict the propensity of selecting into Medicare HMOs and adjust its effect on health spending as well as to quantify the financial impact of Medicare HMO coverage in the first four years, compared to traditional Medicare from 1992 to 2008. There were 1,841 and 4,126 eligible Medicare enrollees included in total and OOP spending models. Results: The pre-Medicare characteristics that were significantly associated with selection into Medicare HMOs included blacks, Hispanic origin, regions of residence and pre-Medicare health plans. The results showed that the average HMO effect on total spending was insignificant, $2,651.0 less than the traditional Medicare plans (SE = 3,761.2, p = 0.46). The saving on OOP spending was significantly $1,411.5 (SE = 620.8, p = 0.03). Conclusion: the HMOs provide better financial protection in OOP health spending for Medicare enrollees in the first four years of Medicare coverage. However, this effect is not significant for total spending. Key words: Medicare, biased selection, HMO (health maintenance organization), propensity score matching
关键词：health services research; public health; health policy; health financing;Medicare; biased selection; HMO (health maintenance organization); propensity score matching
