Flexible modelling of risk factors on the incidence of pneumonia in young children in South Africa using piece-wise exponential additive mixed modelling.

ABSTRACT:

Introduction

Recurrent episodes of pneumonia are frequently modeled using extensions of the Cox proportional hazards model with the underlying assumption of time-constant relative risks measured by the hazard ratio. We aim to relax this assumption in a study on the effect of factors on the evolution of pneumonia incidence over time based on data from a South African birth cohort study, the Drakenstein child health study.

Methods

We describe and apply two models: a time-constant and a time-varying relative effects model in a piece-wise exponential additive mixed model's framework for recurrent events. A more complex model that fits in the same framework is applied to study the continuously measured seasonal effects.

Results

We find that several risk factors (male sex,

SUBMITTER: Ramjith J 

PROVIDER: S-EPMC7802241 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature