Federated learning for violence incident prediction in a simulated cross-institutional psychiatric setting

TL;DR

This paper demonstrates that federated learning can effectively train natural language processing models on clinical notes for violence risk prediction across institutions, outperforming local models and matching centralized data models.

Contribution

It introduces the first application of federated learning to clinical NLP for violence risk assessment in a simulated cross-institutional psychiatric setting.

Findings

Federated model outperforms local models

Federated model performs similarly to centralized model

Shows potential for privacy-preserving cross-institutional NLP applications

Abstract

Inpatient violence is a common and severe problem within psychiatry. Knowing who might become violent can influence staffing levels and mitigate severity. Predictive machine learning models can assess each patient's likelihood of becoming violent based on clinical notes. Yet, while machine learning models benefit from having more data, data availability is limited as hospitals typically do not share their data for privacy preservation. Federated Learning (FL) can overcome the problem of data limitation by training models in a decentralised manner, without disclosing data between collaborators. However, although several FL approaches exist, none of these train Natural Language Processing models on clinical notes. In this work, we investigate the application of Federated Learning to clinical Natural Language Processing, applied to the task of Violence Risk Assessment by simulating a cross-institutional psychiatric setting. We train and compare four models: two local models, a federated model and a data-centralised model. Our results indicate that the federated model outperforms the local models and has similar performance as the data-centralised model. These findings suggest that Federated Learning can be used successfully in a cross-institutional setting and is a step towards new applications of Federated Learning based on clinical notes