To compare infant injuries in the first year of life between Maternal Infant Health Program (MIHP) participants and matched comparison groups. The population was the cohort of Medicaid-insured singleton infants born in 2011 in Michigan who had continuous Medicaid insurance and survived the first year after birth (N = 51,078). Propensity score matching was used to compare participants in MIHP to matched comparison groups from among the nonparticipants. Injury episodes were defined based on Medicaid claims in the first year of life. Matched comparisons were performed using McNemar, Bowker, and Wilcoxon signed rank tests to assess the effects of program participation on infant injuries. Infants of MIHP participants were more likely to have injury episodes (11.7 vs. 10.4 %, p < 0.01) and a higher rate of episodes (126.9/1,000 infants vs. 109.6/1,000) compared to matched nonparticipants. Infants of MIHP participants were more likely to have superficial injuries (4.9 vs. 3.9 %, p < 0.01) and a higher rate of episodes related to superficial injuries (49.7/1,000 vs. 39.6/1,000), which mainly accounted for the difference in injury visits between groups. Similar results were found among those enrolled and risk-screened in the program by the 2nd pregnancy trimester and who received a dosage of at least three additional MIHP contacts when compared to matched nonparticipants. MIHP participants did not experience reductions in infant injuries in the first year of life compared to matched nonparticipants. Possible explanations may include increased health-seeking behavior of the mothers participating in MIHP or improved recognition of infant injuries that warrant medical attention.
Keywords: Enhanced prenatal and postnatal services; Home visitation; Infant injury; Medicaid.