Analyzing the impact of prenatal care on infant health: do we have useful input and output measures?

Recent work raises questions about the input and output measures typically used to estimate the impact of prenatal care on infant health: self-reported prenatal care may generate biased estimates of the impact of prenatal care on infant health, and birthweight may be a narrow measure of infant health that leads to underestimation of the impact of prenatal care on delivery outcomes. We link data from a prenatal care clinic, the associated hospital and the relevant birth certificate records to analyze these measurement issues. We conclude that low birthweight is not meaningful measure of infant health for the purpose of estimating the relation between prenatal care and delivery outcomes. In addition, the discrepancy between provider-reported and self-reported care is substantial, the correlation between these two measures is low, and the estimated relationship between prenatal care and infant health is not robust with respect to reliance on self-reported vs. provider-reported care.