Table 1_The moderating role of the case-mix index in the relationship between medical staff allocation and average cost per inpatient visit.xlsx

BackgroundGreater medical staff allocation and higher Case-Mix Index (CMI) values are both associated with increased patient medical expenditures. However, it remains unclear whether CMI moderates the relationship between medical staff allocation and medical expenditures. The present study focus on whether medical staff allocation predicts the cost per inpatient visit, whether this association is enhanced under conditions of high CMI.
AimTo explore the mechanism underlying the role of the CMI in the relationship between medical staff allocation and the average cost per inpatient visit.
MethodsData were collected from 207 general hospitals in Hubei Province in 2019 using the cluster sampling method. Pearson’s correlations were used to examine the associations between medical staff allocation, the CMI and the cost per inpatient visit. The moderating role of the CMI between medical staff allocation and the average cost per inpatient visit was analyzed using Model 1 of the PROCESS macro.
ResultsThe number of patients per doctor (r = −0.180, p < 0.01), beds per nurse (r = −0.181, p < 0.01), beds per doctor (r = −0.225, p < 0.01) and the average cost per inpatient visit showed a significant negative correlation. The CMI positively moderated the relationship between the average cost per inpatient visit and both the number of beds per doctor (p < 0.01) and the number of beds per nurse (p < 0.01). The moderating effect was stronger when hospitals had high CMI value influencing average cost per inpatient visit.
ConclusionCMI value can enhance the negative effects of the number of beds per doctor or nurse on average cost per inpatient visit, revealing that rational CMI benchmark for the hospital or prioritizing disease categories with clinically appropriate treatment complexity can mitigate the extent to which healthcare workforce allocation influences rising medical expenditures. Reasonable medical staff allocation and the CMI serve as important factors in controlling the average cost per inpatient visit.

研究背景：医疗人员配置规模更大与更高的病例组合指数（Case-Mix Index, CMI）均与患者医疗支出增加呈正相关。然而，目前仍尚不明确CMI是否会在医疗人员配置与医疗支出之间的关联中起到调节作用。本研究旨在探讨两个核心问题：其一，医疗人员配置是否能够预测单次住院就诊的人均成本；其二，在CMI较高的情境下，这一关联是否会得到增强。
研究目的：本研究旨在探究CMI在医疗人员配置与单次住院就诊人均成本之间关联中的作用机制。
研究方法：本研究于2019年采用整群抽样方法，收集了湖北省207家综合医院的相关数据。采用Pearson相关分析检验医疗人员配置、CMI与单次住院就诊人均成本之间的关联；并通过PROCESS宏程序的Model 1，分析CMI在医疗人员配置与单次住院就诊人均成本之间的调节作用。
研究结果：每名医师负责的患者数（r=-0.180，p<0.01）、每名护士负责的床位数（r=-0.181，p<0.01）以及每名医师负责的床位数（r=-0.225，p<0.01），均与单次住院就诊人均成本呈显著负相关。CMI对单次住院就诊人均成本与每名医师负责床位数、每名护士负责床位数之间的关联均存在正向调节作用（p均<0.01）；当医院CMI值较高时，该调节效应更为显著。
研究结论：CMI值可强化每名医师或护士负责床位数对单次住院就诊人均成本的负向影响，这表明：为医院设定合理的CMI基准，或是优先针对临床治疗复杂度适宜的疾病类别进行管理，能够削弱医疗人员配置对医疗支出上涨的影响程度。合理的医疗人员配置与CMI均为控制单次住院就诊人均成本的重要影响因素。