Payment Increases and Physician Supply of Care for Medicaid Beneficiaries

 描述（由申请人提供）：该项目测试如何支付增加影响医疗补助患者的医生护理供应。该研究使用了一个自然实验，其中医疗补助对初级保健服务的报销平均增加了73%，这是由于《平价医疗法案》中的一项规定将医疗补助初级保健费用提高到医疗保险水平。这一政策变化对各州医生的影响不同，基于他们的医疗补助与医疗保险比率。我将使用这个政策实验来测试医生是否通过增加他们为医疗补助患者提供的护理来应对支付增加-正如Athenahealth，Inc.编制的索赔和电子健康记录数据库中所观察到的那样。《平价医疗法案》极大地增加了获得保险的机会，部分原因是通过州医疗补助计划的扩张。扩大覆盖范围引起了人们对获得医疗服务的担忧，特别是因为医生历来不太可能接受医疗补助患者。增加医疗补助对初级保健的补偿旨在激励医生治疗更多的医疗补助患者。我提出的研究将直接测试这一政策的有效性，并为正在进行的关于增加医疗补助报销是否是确保获得的有效策略的辩论提供信息。如果医生通过改变他们对医疗补助患者的医疗服务供应来应对支付增加，这种变化可能采取几种可能的形式。首先，目前治疗医疗补助患者的医生可能会治疗更多。目标1将测试这一点，使用修改后的差异（DD）框架和结果的措施，量化医疗补助患者作为一个医生的面板和医生的总预约时间的份额。DD框架通过比较医疗补助初级保健支付增加之前和之后的医生医疗供应，以及由于他们所在州的前期费用计划慷慨而经历不同价格冲击的医生，确定了支付增加的影响。医生和时间固定效应控制了医生和时间趋势之间结局的基线差异。增加支付也可能激励以前排除医疗补助病人的医生开始接受他们。目标2将使用等于1的二元结局指标对此进行测试，如果医生在该时间段内接受了任何医疗补助患者。估计方程与目标1相似，但由于因变量的二元性质，将使用逻辑回归。最后，医生对增加支付的反应可能会因新患者和已建立的患者而有所不同。目标3侧重于医疗补助新患者获得医生服务的变化。为了评估是否增加支付导致更多的新病人的访问，我将测试是否有一个扩展的百分比的病人在医生的面板谁没有见过，确定了一系列的程序代码保留的办公室访问与新的，而不是建立，病人。

 DESCRIPTION (provided by applicant): This project tests how payment increases affect physician supply of care for Medicaid patients. The study uses a natural experiment in which Medicaid reimbursement for primary care services increased by an average of 73 percent, as a result of a provision in the Affordable Care Act that increased Medicaid primary care fees to Medicare levels. This policy change affected physicians differently across states, based on their Medicaid-to-Medicare ratios. I will use this policy experiment to test whether physicians respond to payment increases by increasing how much care they provide to Medicaid patients - as observed in a database of claims and electronic health record data compiled by athenahealth, Inc. The Affordable Care Act greatly increased access to insurance, partially through state Medicaid expansions. Expanded coverage has generated concern about access to care, particularly as physicians have historically been less likely to accept Medicaid patients. The increase in Medicaid reimbursement for primary care was designed to incentivize physicians to treat more Medicaid patients. My proposed research will directly test the efficacy of this policy and inform an ongoing debate about whether increasing Medicaid reimbursement is an effective strategy for ensuring access. If physicians respond to a payment increase by changing their supply of medical care for Medicaid patients, this change may take a few possible forms. First, physicians who currently treat Medicaid patients may treat more. Aim 1 will test for this, using a modified difference-in-differences (DD) framework and outcome measures that quantify Medicaid patients as a share of a physician's panel and a physician's total scheduled appointment time. The DD framework identifies the effects of payment increases by comparing physician supply of medical before and after the Medicaid primary care payment increase, and across physicians that experienced different price shocks as a result of the pre-period fee schedule generosity in their state. Physician and time fixed effects control for baseline differences in outcomes among physicians and time trends. A payment increase may also incentivize physicians who had previously excluded Medicaid patients to begin accepting them. Aim 2 will test for this using a binary outcome measure equal to one if the physician accepted any Medicaid patients during that time period. The estimating equation is similar to Aim 1, but will use logistic regression, due to the binary nature of the dependent variable. Finally, physicia response to a payment increase may differ by new versus established patients. Aim 3 focuses on changes in access to physician services for new patients with Medicaid. To assess whether increased payment resulted in greater access for new patients, I will test whether there was an expansion in the percent of patients in a physician's panel who had not previously been seen, as identified by a collection of procedure codes reserved for office visits with new, rather than established, patients.