Causal inference in studies of preterm babies: a simulation study.

ABSTRACT:

Objective

Using a simple simulation, we illustrate why associations estimated from studies restricted to preterm births cannot be interpreted causally.

Design, setting and population

Data simulation involving a hypothetical cohort of fetuses who may be healthy or have one or more of four pathological factors (termed A through D, increasing in severity) with known effects on gestational length and risk of mortality. We focus on babies born at ≤32 weeks of gestation.

Methods

We visually represent the simulated population and compare the association between A (which may represent pre-eclampsia) and neonatal death. We then repeat the exercise with D (standing in for chorioamnionitis) as the exposure of interest.

Main outcome measures

Odds ratios of neonatal death i

SUBMITTER: Snowden JM 

PROVIDER: S-EPMC5862739 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature