Division of Health Policy Research and Education, Harvard University, in Boston, Massachusetts, USA.
Health Aff (Millwood). 2012 Dec;31(12):2618-28. doi: 10.1377/hlthaff.2012.0345.
Within Medicare, the Medicare Advantage program has historically attracted better risks-healthier, lower-cost patients-than has traditional Medicare. The disproportionate enrollment of lower-cost patients and avoidance of higher-cost ones during the 1990s-known as favorable selection-resulted in Medicare's spending more per beneficiary who enrolled in Medicare Advantage than if the enrollee had remained in traditional Medicare. We looked at two measures that can indicate whether favorable selection is taking place-predicted spending on beneficiaries and mortality-and studied whether policies that Medicare implemented in the past decade succeeded in reducing favorable selection in Medicare Advantage. We found that these policies-an improved risk adjustment formula and a prohibition on monthly disenrollment by beneficiaries-largely succeeded. Differences in predicted spending between those switching from traditional Medicare to Medicare Advantage relative to those who remained in traditional Medicare markedly narrowed, as did adjusted mortality rates. Because insurance exchanges set up under the Affordable Care Act will employ similar policies to combat risk selection, our results give reason for optimism about managing competition among health plans.
在医疗保险中，医疗保险优势计划历来吸引的风险更小（即更健康、成本更低）的参保者多于传统医疗保险。在 20 世纪 90 年代，这种不成比例的低成本患者参保和避免高成本患者参保的现象——被称为有利选择——导致医疗保险为每一位选择加入医疗保险优势计划的参保者支付的费用高于如果该参保者仍留在传统医疗保险中的费用。我们研究了两种可以表明是否存在有利选择的指标——对参保者的预测支出和死亡率——并研究了医疗保险在过去十年中实施的政策是否成功地减少了医疗保险优势计划中的有利选择。我们发现，这些政策——一个改进的风险调整公式和禁止参保者按月退出——在很大程度上取得了成功。与那些仍留在传统医疗保险中的人相比，从传统医疗保险转为医疗保险优势计划的人的预测支出差异明显缩小，调整后的死亡率也是如此。由于平价医疗法案设立的保险交易所将采用类似的政策来打击风险选择，因此我们的研究结果为管理医疗计划之间的竞争提供了乐观的理由。
