Department of Health Policy and Management, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA.
Health Econ. 2011 Apr;20(4):446-60. doi: 10.1002/hec.1602.
States have increasingly used Health Maintenance Organizations (HMOs) to provide medical services to the Medicaid population. However, the effects of these initiatives on total health-care expenses, the mix of utilization, and access to care remain unclear. We examine the effect of changes in Medicaid HMO penetration between 1996 and 2002 on these outcomes using data for the nonelderly Medicaid population in the Community Tracking Study's Household Survey. We develop market-level measures of Medicaid HMO penetration from CMS and InterStudy data, distinguish whether the HMOs specialize in serving the Medicaid population, and use a market fixed-effects model to focus on changes in HMO penetration rates over time. Although limited by imprecise estimates, we find some evidence that utilization and access are related to the market penetration rates of commercial and Medicaid-dominant HMOs, but the pattern of results we observe does not appear to be consistent with welfare improvements.
各州越来越多地使用健康维护组织（HMO）为医疗补助人群提供医疗服务。然而，这些举措对总医疗费用、利用情况的组合以及获得医疗服务的影响仍不清楚。我们使用社区追踪研究家庭调查中的非老年医疗补助人口数据，考察了 1996 年至 2002 年间医疗补助 HMO 普及率变化对这些结果的影响。我们从 CMS 和 InterStudy 数据中制定了医疗补助 HMO 普及率的市场水平衡量标准，区分了 HMO 是否专门为医疗补助人群服务，并使用市场固定效应模型来关注 HMO 普及率随时间的变化。尽管受到估计不精确的限制，但我们发现一些证据表明，利用情况和获得医疗服务的机会与商业和 Medicaid 主导型 HMO 的市场普及率有关，但我们观察到的结果模式似乎不符合福利改善。
