Workforce quality and early childhood development at scale

Early childhood programmes frequently lose effectiveness at scale, yet the role of the workforce remains poorly understood. We document substantial heterogeneity in workforce effectiveness in England’s national home-visiting programme for first-time teenage mothers, despite a highlystructured curriculum and well-qualified staff. Exploiting quasi-random assignment of mothers to family nurses, we estimate that a one standard deviation increase in workforce effectiveness raises children’s cognitive and socio-emotional development by 0.20-0.23 SD. Structural quality — observable worker characteristics — does not predict effectiveness, but process quality — how visits are delivered — does. Greater effectiveness is linked with improvements in maternal mental health and risk behaviours.