Estimating the effect of Prenatal Care Coordination in Wisconsin: A sibling fixed effects analysis.

OBJECTIVE: To estimate Prenatal Care Coordination's (PNCC) effect on birth outcomes for Wisconsin Medicaid-covered deliveries. DATA SOURCE: A longitudinal cohort of linked Wisconsin birth records (2008-2012), Medicaid claims, and state-administered social services. STUDY
DESIGN: We defined PNCC treatment dichotomously (none vs. any) and by service level (none vs. assessment/care plan only vs. service uptake). Outcomes were birthweight (grams), low birthweight (<2500 g), gestational age (completed weeks), and preterm birth (<37 weeks). We estimated PNCC's effect on birth outcomes, adjusting for maternal characteristics, using inverse-probability of treatment weighted and sibling fixed effects regressions. DATA COLLECTION/EXTRACTION
METHODS: We identified 136 224 Medicaid-paid deliveries, of which 33 073 (24.3 percent) linked to any PNCC claim and 22 563 (16.6 percent) linked to claims for PNCC service uptake. PRINCIPAL
FINDINGS: Sibling fixed effects models-which best adjust for unobserved confounding and treatment selection-produced the largest estimates for all outcomes. For example, in these models, PNCC service uptake was associated with a 1.3 percentage point (14 percent) reduction and a 1.8 percentage point (17 percent) reduction in the probabilities of low birthweight and preterm birth, respectively (all P < .05).
CONCLUSIONS: PNCC's modest but significant improvement of birth outcomes should motivate stronger PNCC outreach and implementation of similar programs elsewhere. © Health Research and Educational Trust.