Austin Peter C, Reeves Mathew J
Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.
Circ Cardiovasc Qual Outcomes. 2014 Mar;7(2):299-305. doi: 10.1161/CIRCOUTCOMES.113.000685. Epub 2014 Mar 11.
Hospital report cards, in which outcomes after the provision of medical or surgical care are compared across healthcare providers, are being published with increasing frequency. However, the accuracy of such comparisons is controversial, especially when case volumes are small. The objective was to determine the relationship between hospital case volume and the accuracy of hospital report cards.
Monte Carlo simulations were used to examine the influence of hospital case volume on the accuracy of hospital report cards in a setting in which true hospital performance was known with certainty, and perfect risk-adjustment was feasible. The parameters used to generate the simulated data sets were obtained from empirical analyses of data on patients hospitalized with acute myocardial infarction in Ontario, Canada, in which the overall 30-day mortality rate was 11.1%. We found that provider volume had a strong effect on the accuracy of hospital report cards. However, provider volume had to be >300 before ≥70% of hospitals were correctly classified. Furthermore, hospital volume had to be >1000 before ≥80% of hospitals were correctly classified.
Producers and users of hospital report cards need to be aware that, even when perfect risk adjustment is possible, the accuracy of hospital report cards is, at best, modest for small to medium-sized case loads (i.e., 100-300). Hospital report cards displayed high degrees of accuracy only when provider volumes exceeded the typical annual hospital case load for many cardiovascular conditions and procedures.
医院报告卡越来越频繁地发布，其中会比较不同医疗服务提供者提供医疗或外科护理后的结果。然而，这种比较的准确性存在争议，尤其是在病例数量较少时。目的是确定医院病例数量与医院报告卡准确性之间的关系。
在已知真实医院表现且可行完美风险调整的情况下，使用蒙特卡洛模拟来检验医院病例数量对医院报告卡准确性的影响。用于生成模拟数据集的参数取自对加拿大安大略省急性心肌梗死住院患者数据的实证分析，其中总体30天死亡率为11.1%。我们发现医疗服务提供者的病例数量对医院报告卡的准确性有很大影响。然而，医疗服务提供者的病例数量必须超过300，才有≥70%的医院能被正确分类。此外，医院病例数量必须超过1000，才有≥80%的医院能被正确分类。
医院报告卡的编制者和使用者需要意识到，即使可以进行完美的风险调整，对于中小病例量（即100 - 300），医院报告卡的准确性充其量也只是一般。只有当医疗服务提供者的病例数量超过许多心血管疾病和手术的典型年度医院病例量时，医院报告卡才显示出高度的准确性。
