Data source and data collection
Women eligible for the study were found using CTcue®,
an Artificial Intelligence searching program developed to collect data
from Electronic Patient Files (EPF) of our clinic
(CTcue®, version 2.1.1.10, Amsterdam, Netherlands).
Data were collected in CTcue® and further processed in Rstudio.
Statistical methods
A directed acyclic graph (DAG) was constructed by using the online
DAGitty software (http://www.dagitty.net/) to select covariates for
inclusion in the statistical models.
The relationships between each of the variables were assigned based on
knowledge of the publications regarding these associations. Concerning
assumptions described in the DAG theory, a minimal sufficient set of
adjustment variables was identified for estimating the effect of BDZs
use on maternal and neonatal risks.