Journal of Policy Analysis and Management · 2026 · Moiz Bhai、Danny R. Hughes
中文摘要
我们利用 Medicare 资格初始参保期所带来的准实验变异，考察并描述 Medicare Advantage 的参与情况，以此探究 Medicare Advantage 中自选择这一根本性问题。利用 2007 年至 2017 年的行政理赔数据，我们考察了一个覆盖全面的商业保险参保人群子样本从商业保险向 Medicare Advantage 的转变。我们利用美国最大的商业保险与 Medicare Advantage 数据库之一中 65 岁的明确断点，实施了一项“正相关”检验。基于 64 岁时基线特征的研究结果揭示，Medicare Advantage 的参保者在多项健康状况指标上 (如 Charlson 合并症指数 (CCI) 得分、自付费用、医疗服务利用) 呈现优势选择，而在人口学特征上则呈现差异化选择。此外，利用基于可观测特征预测的 Medicare Advantage 医疗服务利用情况，我们发现了更强的优势选择证据，表明 64 岁时的可观测特征能够系统性地预测哪些参保者将从 Medicare Advantage 的各项特征中获益最多，提示存在前瞻性的选择行为。
Abstract
ABSTRACT We explore the fundamental question of selection in Medicare Advantage by exploiting quasi‐experimental variation from the Initial Enrollment Period for Medicare eligibility to evaluate and describe participation in Medicare Advantage. Using administrative claims data between 2007 and 2017, we investigate the transition from commercial insurance to Medicare Advantage for a comprehensive subset of commercially insured enrollees. We use the sharp cutoff at age 65 in one of the largest commercial and Medicare Advantage databases in the United States to implement a “positive correlation” test. Our findings using baseline characteristics at age 64 reveal that enrollees in Medicare Advantage are advantageously selected on multiple measures of health status such as Charlson Comorbidity Index (CCI) scores, out‐of‐pocket costs, utilization, while differentially selected on demographic characteristics. Furthermore, using predicted Medicare Advantage utilization based on observable characteristics, we find even stronger evidence of advantageous selection, suggesting that observable characteristics at age 64 systematically predict which enrollees would benefit most from Medicare Advantage's features, indicating forward‐looking selection behavior.