Learning the Graphical Structure of Electronic Health Records with Graph Convolutional Transformer
This addresses the challenge of modeling EHR data without complete structural information, which is incremental as it builds on prior work using graphical structures.
The paper tackles the problem of incomplete or missing graphical structure in electronic health records (EHR) by proposing a model that jointly learns hidden structure while performing supervised prediction tasks, resulting in consistent empirical outperformance on tasks like graph reconstruction and readmission prediction.
Effective modeling of electronic health records (EHR) is rapidly becoming an important topic in both academia and industry. A recent study showed that using the graphical structure underlying EHR data (e.g. relationship between diagnoses and treatments) improves the performance of prediction tasks such as heart failure prediction. However, EHR data do not always contain complete structure information. Moreover, when it comes to claims data, structure information is completely unavailable to begin with. Under such circumstances, can we still do better than just treating EHR data as a flat-structured bag-of-features? In this paper, we study the possibility of jointly learning the hidden structure of EHR while performing supervised prediction tasks on EHR data. Specifically, we discuss that Transformer is a suitable basis model to learn the hidden EHR structure, and propose Graph Convolutional Transformer, which uses data statistics to guide the structure learning process. The proposed model consistently outperformed previous approaches empirically, on both synthetic data and publicly available EHR data, for various prediction tasks such as graph reconstruction and readmission prediction, indicating that it can serve as an effective general-purpose representation learning algorithm for EHR data.