Validation of a comorbidity index for use in obstetric patients: A nationwide cohort study

A previously developed Obstetric Comorbidity Index has been validated in highly selected cohorts. Validation of the index in an unselected population as well as in other health registers is, however, of high importance to determine external validity.Using nationwide registers, we formed a nationwide cohort including completed pregnancies (both live- and stillborn) in Denmark from 2000 through 2014. Maternal age and 20 comorbid conditions were...