Project Summary
The project team is developing plausible estimates of the causal effects of the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) on infant and child outcomes. The investigators focus on the effects of WIC on children after they are born; spillover effects from targeted children to other family members who are not directly eligible for the programs; and on the effects of changes to the composition of the WIC food package and delivery of program benefits (e.g., changes from an identifiable voucher to an Electronic Benefits Transfer (EBT) card).
Research Questions/Aims
- What are the effects of aging out of the 6-11 month old infant WIC package and into the child package at age 1 year?
- What is the effect of aging out of WIC entirely at age 5 years?
- What are the spillover effects on household members when a child in the household ages out of WIC at age 5 years?
Actionability
- Inform policy decisions regarding WIC by providing a broader range of effects WIC may have on health, well-being, and nutrition for children and families.
Outcomes
| Outcome | Primary or Exploratory RD Design |
Primary or Exploratory DD Design |
Data Set |
|---|---|---|---|
| WIC Participation | Primary | Primary | NHANES Questionnaire |
| Foods purchased in WIC Basket | Primary | Primary | Nielsen HomeScan |
| Foods purchased, substitutes/complements to WIC basket | Primary | Primary | Nielsen HomeScan |
| Self-reported consumption, in WIC basket | Primary | Primary | NHANES Dietary Interview |
| Self-reported consumption, subsitutes/complements to WIC basket | Primary | Primary | NHANES Dietary Interview |
| Self-reported nutrient intake, WIC targeted (e.g., iron) | Primary | Primary | NHANES Dietary Interview |
| Self-reported nutrient intake, Not targeted pre-2009 package change (e.g., fiber) | Exploratory | Primary | NHANES Dietary Interview |
| Food Insecurity | Primary | Primary | NHANES Questionnaire |
| Laboratory blood tests, adjusts quickly (e.g., ferritin) | Primary | Primary | NHANES Laboratory |
| Laboratory blood tests, adjusts slowly (e.g., vitamins A, D) | Exploratory | Primary | NHANES Laboratory |
| Hospital visit, type/diagnoses | Exploratory | Exploratory | HCUP |
| Body measures (weight, BMI) | Exploratory | Exploratory | NHANES Examination |
Methodology
The investigators are using a regression discontinuity (RD) strategy to compare outcomes for children at ages just younger than the sharp changes in the program benefits and eligibility to those for children just older than the relevant age thresholds, considering children near ages 1 and 5 as the two relevant thresholds. A differences-in-differences (DD) design is used estimate the effect of change to the revised WIC package and the effect of the change to EBT cards from vouchers.
University of California, Davis
Princeton University Center for Health and Well Being
University of California, Berkeley
University of North Carolina at Charlotte
Cornell University