Managed care provides health insurers a unique opportunity for discretion over certain aspects of financial reporting. Specifically, managed care mechanisms provide health insurers with a stronger ability to engage in loss control. To test whether and how health insurers exploit their ability to manage losses, we examine whether insurers with greater opportunity to manage care report significantly better underwriting performance in the fourth quarter relative to other health insurers. Using quarterly statutory filings from 2003 to 2016, we find evidence that a health insurer’s share of enrollment in health maintenance organisation (HMO) plans, characterised by their use of ‘gatekeeper’ physicians, is significantly and negatively related to their reported fourth quarter medical loss ratio (MLR). Additionally, while we find that fourth quarter MLRs are higher for all health insurers following the implementation of the Patient Protection and Affordable Care Act (ACA), the ACA does not appear to have intensified the loss control efforts of those insurers with more enrollment in HMO plans.

管理式医疗为健康保险公司提供了在财务报告某些方面进行酌处权的独特机会。具体而言，管理式护理机制为健康保险公司提供了更强的参与损失控制的能力。为了测试健康保险公司是否以及如何利用其管理损失的能力，我们研究了拥有更大机会管理保险的保险公司报告的第四季度的承保业绩相对于其他健康保险公司而言明显更好。使用2003年至2016年的季度法定文件，我们发现有证据表明，健康保险公司在健康维持组织（HMO）计划中的入学份额与他们报告的第四季度医疗损失呈显着负相关，该组织以使用“看门人”医师为特征比率（MLR）。此外，