Baby's First Years is the first randomized controlled trial in the United States to examine the causal impact of unconditional cash payments on children's early cognitive, socio-emotional, and brain development over 52 months. Researchers recruited 1,000 mothers with infants and incomes below the federal poverty line residing near study sites in New Orleans, LA, the Twin Cities (Minneapolis, MN and St. Paul, MN), Omaha, NE, and New York, NY. Participants were randomized via parallel assignment into either the high cash gift group (n=400) to receive $333 per month ($4,000 per year) or the low cash gift group (n=600) to receive $20 per month ($240 per year).

Following the baseline visit, participants completed follow-up assessments on an annual basis. The files released in the ICPSR repository contain de-identified data from the baseline and follow-up visits (Years 1 to 4).