Maxwell School of Citizenship and Public Affairs, Syracuse University, NY.
Division of Internal Medicine, Division of Cardiovascular Medicine, University of Michigan.
Med Care. 2020 Nov;58(11):1022-1029. doi: 10.1097/MLR.0000000000001396.
The objective of this study was to examine variation in hospital responses to the Centers for Medicare and Medicaid's expansion of allowable secondary diagnoses in January 2011 and its association with financial penalties under the Hospital Readmission Reduction Program (HRRP).
DATA SOURCES/STUDY SETTING: Medicare administrative claims for discharges between July 2008 and June 2011 (N=3102 hospitals).
We examined hospital variation in response to the expansion of secondary diagnoses by describing changes in comorbidity coding before and after the policy change. We used random forest machine learning regression to examine hospital characteristics associated with coded severity. We then used a 2-part model to assess whether variation in coded severity was associated with readmission penalties.
Changes in severity coding varied considerably across hospitals. Random forest models indicated that greater baseline levels of condition categories, case-mix index, and hospital size were associated with larger changes in condition categories. Hospital coding of an additional condition category was associated with a nonsignificant 3.8 percentage point increase in the probability for penalties under the HRRP (SE=2.2) and a nonsignificant 0.016 percentage point increase in penalty amount (SE=0.016).
Changes in patient coded severity did not affect readmission penalties.
本研究旨在考察 2011 年 1 月医疗保险和医疗补助服务中心（Centers for Medicare and Medicaid）扩大允许的次要诊断范围后，医院的反应差异及其与医院再入院减少计划（Hospital Readmission Reduction Program，HRRP）下的财务处罚之间的关系。
数据来源/研究范围：2008 年 7 月至 2011 年 6 月（N=3102 家医院）间出院患者的医疗保险行政索赔数据。
我们通过描述政策变更前后合并症编码的变化，考察了医院对次要诊断扩展的反应差异。我们使用随机森林机器学习回归分析来考察与编码严重程度相关的医院特征。然后，我们使用两部分模型来评估编码严重程度的差异是否与再入院处罚相关。
严重程度编码的变化在各医院之间差异很大。随机森林模型表明，基线条件类别、病例组合指数和医院规模越大，条件类别的变化越大。医院编码额外的条件类别与 HRRP 下处罚的可能性增加了 3.8 个百分点（SE=2.2），且处罚金额增加了 0.016 个百分点（SE=0.016），但均无统计学意义。
患者编码严重程度的变化并未影响再入院处罚。
