Objective: The objective was to develop, validate, and recommend a scaling model for a discriminative obstetric outcome measure named the Morbidity Assessment Index for Newborns. The purpose of this tool is to allow comparison of obstetric therapeutic strategies on neonatal morbidity, particularly in the mild to moderate morbidity range.
Study design: A list of 66 check-mark (yes or no) items of readily available clinical and laboratory data from the early neonatal period was compiled by a panel of obstetric and neonatal experts. These data were collected on 411 neonates born at >/=28 weeks' gestation and representing all grades of morbidity. Detailed psychometric testing included dimensionality testing and item analysis with the item response theory. The scores obtained with this new assessment tool were correlated with newborn and maternal disease conditions or events and with other measures of newborn morbidity.
Results: The Morbidity Assessment Index for Newborns is easy to apply in prospective or retrospective studies. Detailed psychometric evaluation resulted in modification of the list to 47 items, each item with a relative scale value according to severity of morbidity. The test was demonstrated to be a reliable and generalizable scaled index that performs optimally for the mild to moderate neonatal morbidity range.
Conclusion: The Morbidity Assessment Index for Newborns is a validated outcome measurement scale of neonatal morbidity. This new tool may facilitate the conduct of obstetric clinical trials or epidemiologic population-based studies in obstetrics.