Abstract
In the Baby’s First Years (BFY) study, one thousand infants born to mothers with incomes falling below the federal poverty threshold in four metropolitan areas in the United States were assigned at random within each of the metropolitan areas to one of two cash gift conditions. The sites are: New York City, the greater New Orleans metropolitan area, the greater Omaha metropolitan area, and the Twin Cities. IRB and recruiting issues led to a distribution of the 1,000 mothers across sites of 121 in one site (the Twin Cities), 295 in two of the other sites (New Orleans and Omaha) and 289 in New York. (The investigators have also randomly sampled 80 of the participating families in the Twin Cities and New Orleans to participate in an in-depth qualitative study, but do not elaborate on those plans in this document.)
Mothers were recruited in postpartum wards of the 12 participating hospitals shortly after giving birth and, after consenting, were administered a 30-minute baseline interview. They then were asked to agree to receive the cash gifts. The “high-cash gift” treatment group mothers (40% of all mothers) are receiving unconditioned cash payments of $333 per month ($4,000 per year) via debit card for 76 months. Mothers in the “low-cash gift” comparator group (60% of all mothers) are receiving a nominal payment – $20 per month, delivered in the same way and also for 76 months. The 40/60 randomization assignment is stratified by site, but not by hospitals, within each of the four sites. The investigators have worked with state and local officials to ensure that, to the extent feasible, the cash gifts are not considered countable income for the purposes of determining benefit levels from social assistance programs.
BFY was originally formulated to study the effects of monthly unconditional cash gifts on child development for the first three years of life, with the cash gifts set to be distributed for 40 months (3 years, 4 months). In response to the COVID-19 pandemic and the need to postpone in-person research activities, the cash gifts were extended for an additional year, through 52 months (4 years, 4 months), enabling us to postpone in-person direct child assessments to age 4. The investigators successfully arranged funding to extend the cash gifts for a total of 76 months and informed the study participants in August 2022 about the additional 2-year extension of cash transfer.
The targeted age for each data collection wave is around the child’s birthday, i.e. at 12 months, 24 months, 36 months, 48 months, 72 months, and 96 months. Interviews conducted at child ages 1, 2 and 3 provided information about family functioning as well as several maternal reports of developmentally-appropriate measures of children’s cognitive and behavioral development. At ages 4, 6 and 8 measures of cognitive, language, and self-regulation development were or will be administered at university sites, while socio-emotional development is assessed via maternal report. EEG-based measures of brain activity were assessed in the home at age 1 and at university sites at ages 4, 6 and 8. At age 6 and 8 the investigators will collect school behavior and engagement data.
Conditional on participants’ consent and our success in securing agreements with state and county agencies, the investigators are also collecting state and local administrative data regarding maternal employment, utilization of public benefits such as TANF and Supplemental Nutrition Assistance Programs (SNAP), and any involvement in child protective services.
The family process measures that the investigators will gather are based on two theories of change surrounding the income supplements: that increased investment and reduced stress will facilitate children’s healthy development. The investigators are obtaining some measures to capture each of these pathways annually. Investment pathway: Additional resources enable parents to buy goods and services for their families and children that support cognitive development. These include higher quality housing, nutrition and non-parental child care; more cognitively stimulating home environments and learning opportunities outside of the home; and, by reducing or restructuring work hours, more parental time spent with children. Stress pathway: A second pathway is that additional economic resources may reduce parents’ own stress and improve their mental health. This may improve parenting, a more predictable family life, less conflicted relationships, and warmer and more responsive interactions.
The cash gift difference between families in the high and low cash gift groups equals $3,760 per year, an amount shown in the economics and developmental psychology literatures to be associated with socially significant and policy relevant improvements in children’s school achievement. After accounting for likely attrition, a total sample size of 800 at age 4, 6 and 8 years, divided 40/60 between high and low cash gift groups, provides sufficient statistical power to detect meaningful (roughly .20 SD) differences in cognitive, emotional and brain functioning, and key dimensions of family context.
Measures and preregistered hypotheses about child- and family-based measures are shown in the two tables in the statistical analysis plan. Child-focused preregistered hypotheses are presented in Appendix Table 9 and maternal and family focused preregistered hypotheses are presented in Appendix Table 10 in the Statistical Analysis Plan. The investigators will update this registry with Age 8 measures and preregistered hypotheses before data collection begins in July 2026. The assessments at child ages 6 and 8 are part of Phase 2 of the project. The Phase 1 analysis plan can be found in the previous version of this document.
For current information about the study, please see babysfirstyears.com. Publicly available data from the baseline survey and Age 1, 2, and 3 can be found here: https://www.icpsr.umich.edu/web/ICPSR/studies/37871.