Original and refitted HOSPITAL scores as predictors of 30-day potentially avoidable hospital readmissions: retrospective cohort study (Preprint)

BACKGROUND Hospital readmissions are associated with several negative health outcomes and higher hospital costs. The HOSPITAL score is one of the tools developed to identify patients at high risk of hospital readmission, but its predictive capacity in more heterogeneous populations involving different diagnoses and clinical contexts is poorly understood. OBJECTIVE The aim of this study was to propose a refitted HOSPITAL score to predict the risk of potentially avoidable readmission in 30 days and compare the predictive capacity of the original and refitted HOSPITAL score. METHODS Retrospective cohort study was carried out in a tertiary university hospital with patients over the age of 18 years. We developed a refitted HOSPITAL score with the same definitions and predictive variables included in the original HOSPITAL score and compared the predictive capacity of both. The receiver operating characteristic was constructed by comparing the performance risk forecasting tools measuring the area under the curve (AUC). RESULTS Of the 47,464 patients 50.9% were over 60 years and 58.4% were male. The frequency of 30-day potentially avoidable readmission is 7.70% (3638). The accuracy of HOSPITAL score in readmission was AUC: 0.733 (CI 95%: 0.718, 0.748) and the accuracy of HOSPITAL score refitted was AUC: 0.7401 (CI 95%: 0.7256, 0.7547). The frequency of 60, 90, 180, and 365-days readmissions ranged from 10.60% (5,033) to 18.30% (8693). Discussion: Readmission prediction tools have been developed in recent years, but its predictive capacity in more population with different diagnoses is poorly understood. CONCLUSIONS The refitted HOSPITAL score have similar discrimination to predict 30-day potentially avoidable readmission, in patients with different diagnoses. In this sense, our study expands and reinforces the usefulness of the HOSPITAL score as a tool that can be used as part of intervention strategies to reduce the rate of hospital readmission.