The hazard of using the Poisson model to cope with immortal time bias in the case of time-varying hazard.

ABSTRACT:

Background

A time-dependent analysis, usually by means of Poisson and Cox regression models, can be applied to prevent immortal time bias. However, the use of the Poisson model requires the assumption that the event rate is constant over time. This study aims to assess the potential consequences of using the Poisson model to cope with immortal time bias on estimating the exposure-outcome relationship in the case of time-varying risks.

Methods

A simulation study was carried out. Survival times were assumed to follow a Weibull distribution, and the Weibull parameters were chosen to identify three different scenarios: the hazard of the event is constant, decreases, or increases over time. A dichotomous time-varying exposure in which patients can change at most once from unexpos

SUBMITTER: Rea F 

PROVIDER: S-EPMC11549743 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature