Address correspondence to E. Michael Foster, Ph.D., Professor, Gillings School of Global Public Health, University of North Carolina, Rosenau Hall, Campus Box# 7445, Chapel Hill, NC 27599-7445; e-mail: email@example.com. Miao Jiang, M.S., is with the Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC. Christina M. Gibson-Davis, Assistant Professor, is with the Terry Sanford Institute of Public Policy, Duke University, Durham, NC.
The Effect of the WIC Program on the Health of Newborns
Article first published online: 29 APR 2010
© Health Research and Educational Trust
Health Services Research
Volume 45, Issue 4, pages 1083–1104, August 2010
How to Cite
Foster, E. M., Jiang, M. and Gibson-Davis, C. M. (2010), The Effect of the WIC Program on the Health of Newborns. Health Services Research, 45: 1083–1104. doi: 10.1111/j.1475-6773.2010.01115.x
- Issue published online: 8 JUL 2010
- Article first published online: 29 APR 2010
- birth outcomes;
- propensity score;
- multiple imputations;
- fixed-effects model
Objective. To determine the effect of the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) on birth outcomes.
Data Source. The Child Development Supplement (CDS) of the Panel Study of Income Dynamics (PSID). The PSID provides extensive data on the income and well-being of a representative sample of U.S. families from 1968 to present. The CDS collects information on the children in PSID families ranging from cognitive, behavioral, and health status to their family and neighborhood environment. The first two waves of the CDS were conducted in 1997 and 2002, respectively. We use information on 3,181 children and their mothers.
Study Design. We use propensity score matching with multiple imputations to examine whether WIC program influences birth outcomes: birth weight, prematurity, maternal report of the infant's health, small for gestational age, and placement in the neonatal intensive care unit. Furthermore, we use a fixed-effects model to examine the above outcomes controlling for mother-specific unobservables.
Principal Findings. After using propensity scores to adjust for confounding factors, WIC shows no statistically significant effects for any of six outcomes. Fixed-effects models, however, reveal some effects that are statistically significant and fairly substantial in size. These involve preterm birth and birth weight.
Conclusions. Overall, the WIC program had moderate effects, but findings were sensitive to the estimation method used.