Enhance the after-discharge mortality rate prediction via learning from the medical notes

TL;DR

This paper demonstrates that incorporating medical notes into machine learning models significantly improves after-discharge mortality prediction accuracy, and proposes a deep neural network with pooling to enhance this process.

Contribution

It introduces a novel DNN model with pooling that effectively learns from medical notes, outperforming traditional models in mortality prediction tasks.

Findings

Medical notes increase AUC-ROC by about 0.1 in mortality prediction.

Proposed DNN model improves AUC-ROC by 2% to 14% over traditional models.

Models reveal relationships between keywords in notes and patient severity.

Abstract

With the increase of the Electronic Health Records (EHR) data, more and more researchers are developing machine learning models to learn from the medical notes. These unstructured text data pose significant challenges on the learning process as the quality of data is low. These data are often messy, repetitive and redundant. We have shown these notes data to be informative by conducting the after-discharge mortality rate prediction task. The AUC-ROC for models using the medical note information is generally 0.1 higher than those without the medical notes. Furthermore, we propose the Deep Neural Network(DNN) model with 'pooling' mechanism to enhance the mortality prediction. Based on the experimental results, we demonstrate that the proposed model outperforms the traditional machine learning models like the tree-based models. The proposed method learns from the most informative medical notes and improves the prediction accuracy significantly. The AUC-ROC for the proposed model is 2% to 14% higher than the traditional ones in 15-days, 30-days, 60-days, 365-days after-discharge mortality prediction tasks. Moreover, we can discover some interesting knowledge through the traditional and proposed models. These knowledge are inspiring but also consistent with the previous findings. The models are able to reveal the relationships between the informative keywords and documents from the medical notes and the severity of the patients.