Using threshold Cox models to estimate change points in exposure-response relationships in an occupational epidemiological study of respirable crystalline silica and silicosis risk.

ABSTRACT:

Introduction

In occupational epidemiology, accurately quantifying exposure-response relationships is crucial.

Methods

We introduce a threshold Cox model that includes a change point term to identify the optimal threshold. To address bias associated with maximum likelihood estimation under monotone likelihood, we employ Firth's penalized likelihood approach. The methodology was validated using simulation studies that evaluated model performance under various censoring rates and sample sizes. We applied our threshold Cox model to data from an occupational epidemiological study of respirable crystalline silica (RCS) exposure and risk of silicosis (defined as ILO category 1/0 or higher). To improve the condition of the data for analysis using Cox regression, which is sensitive t

SUBMITTER: Wu D 

PROVIDER: S-EPMC12491331 | biostudies-literature | 2025

REPOSITORIES: biostudies-literature