Long Sharon K, Coughlin Teresa, King Jennifer
Health Policy Center, The Urban Institute, Washington, DC 20037, USA.
Health Serv Res. 2005 Feb;40(1):39-58. doi: 10.1111/j.1475-6773.2005.00341.x.
To provide an assessment of how well the Medicaid program is working at improving access to and use of health care for low-income mothers.
DATA SOURCE/STUDY SETTING: The 1997 and 1999 National Survey of America's Families, with state and county information drawn from the Area Resource File and other sources.
Estimate the effects of Medicaid on access and use relative to private coverage and being uninsured, using instrumental variables methods to control for selection into insurance status.
DATA COLLECTION/EXTRACTION METHOD: This study combines data from 1997 and 1999 for mothers in families with incomes below 200 percent of the federal poverty level.
We find that Medicaid beneficiaries' access and use are significantly better than those obtained by the uninsured. Analysis that controls for insurance selection shows that the benefits of having Medicaid coverage versus being uninsured are substantially larger than what is estimated when selection is not accounted for. Our results also indicate that Medicaid beneficiaries' access and use are comparable to that of the low-income privately insured. Once insurance selection is controlled for, access and use under Medicaid is not significantly different from access and use under private insurance. Without controls for insurance selection, access and use for Medicaid beneficiaries is found to be significantly worse than for the low-income privately insured.
Our results show that the Medicaid program improved access to care relative to uninsurance for low-income mothers, achieving access and use levels comparable to those of the privately insured. Our results also indicate that prior research, which generally has not controlled for selection into insurance coverage, has likely understated the gains of Medicaid relative to uninsurance and overstated the gains of private coverage relative to Medicaid.
评估医疗补助计划在改善低收入母亲获得医疗保健服务及使用医疗服务方面的成效。
数据来源/研究背景:1997年和1999年美国全国家庭调查,州和郡信息取自地区资源文件及其他来源。
使用工具变量法控制保险状态选择,估计医疗补助相对于私人保险覆盖和未参保情况在获得医疗服务及使用医疗服务方面的影响。
数据收集/提取方法:本研究合并了1997年和1999年家庭收入低于联邦贫困线200%的母亲的数据。
我们发现医疗补助受益人的医疗服务可及性和利用率显著优于未参保者。控制保险选择的分析表明,拥有医疗补助覆盖相对于未参保的益处,比不考虑选择因素时的估计值要大得多。我们的结果还表明,医疗补助受益人的医疗服务可及性和利用率与低收入的私人参保者相当。一旦控制了保险选择因素,医疗补助下的可及性和利用率与私人保险下的可及性和利用率没有显著差异。如果不控制保险选择因素,会发现医疗补助受益人的可及性和利用率显著低于低收入的私人参保者。
我们的结果表明,相对于未参保情况,医疗补助计划改善了低收入母亲获得医疗服务的机会,使其可及性和利用率达到了与私人参保者相当的水平。我们的结果还表明,以往的研究通常没有控制保险覆盖选择因素,可能低估了医疗补助相对于未参保的益处,高估了私人保险覆盖相对于医疗补助的益处。