Analysing repeated hospital readmissions using data mining techniques

Abstract

Few studies have examined how to identify future readmission of patients with a large number of repeat emergency department (ED) visits. We explore 30-day readmission risk prediction using Microsoft's AZURE machine learning software and compare five classification methods: Logistic Regression, Boosted Decision Trees (BDTs), Support Vector Machine (SVM), Bayes Point Machine (BPM), and Two-Class Neural Network (TCNN). We predict the last readmission visit of frequent ED patients extracted from the electronic health records of their 8455 penultimate visits. The methods show differential improvement, with the BDT indicating marginally better AUC (area under the ROC curve) than logistic regression and BPM, followed by the TCNN and SVM. A comparison of BDT and Logistic Regression results for correct and incorrect classification highlights the similarities and differences in the significant predictors identified by each method. Future research may incorporate time-varying covariates to identify other longitudinal factors that can lead to readmission risk reduction.

Keywords: Hospital readmissions; boosted decision tree; logistic regression; predicting readmissions; support vector machine; two-class neural network.

Figure 1.

Two-class classification comparisons with AZURE ML: BDT, logistic regression, SVM, BPM and two-class neural network (TCNN).

Figure 2.

Example of one BDT produced by AZURE ML (out of 479 trees).

Figure 3.

Comparisons of ROC curves.