Evaluating WIC.

The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) has enjoyed extraordinary bipartisan support stemming from the widespread belief that research studies have proven that WIC "works." Although some studies suggest real dietary and health improvements, the greatest benefits only apply to WIC's prenatal program (just a small part of the total program). Even here, weaknesses in the research render the findings highly uncertain. The three most significant weaknesses are (1) selection bias, (2) simultaneity bias, and (3) lack of generalizeability. The resulting uncertainty places WIC's possible impacts on infant mortality, prematurity, and birthweight on a range from zero to substantial. For infants, children, and postpartum and breastfeeding mothers, the only impacts seem to be small to modest effects on anemia and nutrient intake. This paper does not argue that WIC's weaknesses justify abandoning or even cutting the program. On the contrary, there should be a sustained effort to make the program more effective. This effort should start with a policy debate about WIC's role and impacts, coupled with a grant of greater flexibility to state and local WIC agencies to open the program to innovation and experimentation. To increase WIC's positive impacts, we propose a series of possible reforms, each to be thoroughly evaluated.