Domain constraints improve risk prediction when outcome data is missing

Published: 28 Oct 2023, Last Modified: 02 Apr 2024DistShift 2023 OralEveryoneRevisionsBibTeX
Keywords: Bayesian model, health, selective labels, distribution shift, domain constraint, biomedicine
TL;DR: We propose the use of domain constraints to improve disease risk prediction in the presence of missing outcome data for the historically untested population
Abstract: Machine learning models often predict the outcome resulting from a human decision. For example, if a doctor tests a patient for disease, will the patient test positive? A challenge is that the human decision *censors* the outcome data: we only observe test outcomes for patients doctors historically tested. Untested patients, for whom outcomes are unobserved, may differ from tested patients along observed and unobserved dimensions. We describe a Bayesian model to capture this setting whose purpose is to estimate risk for both tested and untested patients. To aid model estimation, we propose two *domain-specific* constraints which are plausible in health settings: a *prevalence constraint*, where the overall disease prevalence is known, and an *expertise constraint*, where the human decision-maker deviates from purely risk-based decision-making only along a constrained feature set. We show theoretically and on synthetic data that the constraints can improve parameter inference. We apply our model to a case study of cancer risk prediction, showing that the model can identify suboptimalities in test allocation and that the prevalence constraint increases the plausibility of inferences.
Submission Number: 38