Cots Francesc, Mercadé Lluc, Castells Xavier, Salvador Xavier
Health Services Research Unit, Municipal Institute of Health, IMAS, Hospital del Mar, Passeig Marítim 25-29 E-08003, Barcelona, Spain.
Health Policy. 2004 May;68(2):159-68. doi: 10.1016/j.healthpol.2003.09.004.
Hospital structural level has been suggested as a factor that could explain part of the resource use variation left unexplained by diagnosis related groups (DRGs). However, the relationship between hospital structural level and the presence of cases of extreme resource use (outliers) is not known. Some prospective payment systems pay these cases separately.
To analyze the relationship between different hospital structural levels, defined according to hospital size, teaching activity and location, and the presence of length of stay (LOS) outliers.
A logit model was used to analyze the patient discharge records of the acute care public hospitals' Minimum Data Set in Catalonia (Spain) in 1998. The final population contained 631,096 discharges grouped in 329 adjacent DRGs.
LOS outliers were defined as cases with a LOS exceeding the geometric mean plus two standard deviations of all the stays in the same DRG. The 64 public hospitals of the Catalan health system were classified into large urban teaching hospitals, medium-sized teaching and community hospitals, and small community hospitals according to their structural complexity. The model also controlled for patient and health care process characteristics.
Outliers accounted for 4.5% of total discharges distributed as follows: large urban teaching hospitals (5.6%), medium-sized teaching and community hospitals (4.6%), small community hospitals (3.6%). The probability of a patient being an outlier was higher in hospitals with greater structural complexity: large urban teaching hospitals (OR = 1.59), medium teaching and community hospitals (OR = 1.30) and small community hospitals (OR = 1). Adjustment through the control variables reduced differences among hospitals: large urban teaching hospitals (OR = 1.32), medium-sized teaching and community hospitals (OR = 1.22), and small community hospitals (OR = 1), but the differences remained significant (P < 0.01).
Hospital structural level influences the presence of outliers even when controlling for patient and process characteristics. Thus, some outliers are due to hospital structural level and are not justified by patient characteristics.
医院结构水平被认为是一个可以解释部分诊断相关组（DRG）未解释的资源使用差异的因素。然而，医院结构水平与极端资源使用病例（异常值）的存在之间的关系尚不清楚。一些前瞻性支付系统会单独支付这些病例。
分析根据医院规模、教学活动和地理位置定义的不同医院结构水平与住院时间（LOS）异常值存在之间的关系。
使用逻辑模型分析了1998年西班牙加泰罗尼亚急性护理公立医院最小数据集的患者出院记录。最终人群包括631,096例出院病例，分为329个相邻的DRG。
LOS异常值定义为住院时间超过同一DRG中所有住院时间的几何平均数加两个标准差的病例。加泰罗尼亚卫生系统的64家公立医院根据其结构复杂性分为大型城市教学医院、中型教学和社区医院以及小型社区医院。该模型还控制了患者和医疗过程特征。
异常值占总出院病例的4.5%，分布如下：大型城市教学医院（5.6%）、中型教学和社区医院（4.6%）、小型社区医院（3.6%）。结构复杂性较高的医院中患者成为异常值的概率更高：大型城市教学医院（比值比[OR]=1.59）、中型教学和社区医院（OR=1.30）以及小型社区医院（OR=1）。通过控制变量进行调整减少了医院之间的差异：大型城市教学医院（OR=1.32）、中型教学和社区医院（OR=1.22）以及小型社区医院（OR=1），但差异仍然显著（P<0.01）。
即使控制了患者和过程特征后，医院结构水平仍会影响异常值的存在。因此，一些异常值是由医院结构水平导致的，并非由患者特征所决定。
