Rethinking the Definition of Evidence-Based Interventions to Promote Early Childhood Development

Half a century of research has documented that early childhood interventions can produce positive outcomes in multiple domains, but impacts are typically small to moderate, and few programs have been scaled effectively. Peacock-Chambers et al1 have reviewed the past 2 decades of pediatric-based interventions between birth and age 3, and in their findings they underscore 2 challenges facing the early childhood field: the urgent need for new strategies that produce larger, scalable impacts on important dimensions of child development, and the equally compelling need to revisit the criteria for defining a program as “evidence-based.” The conventional definition, which simply requires a statistically significant difference between a treatment and comparison group on any of a wide range of child and/or parent outcomes, is highly problematic. When interventions are not linked to specific impacts based on explicit causal hypotheses, the variability of effects on multiple measures at different points in time is impossible to interpret and is rarely replicated. A focus on average effects also obscures what may be working exceptionally well for some (which should trigger targeted replication and scaling) and poorly for … Address correspondence to Jack P. Shonkoff, MD, Center on the Developing Child at Harvard University, 50 Church St, Cambridge, MA 02138. E-mail: jack_shonkoff{at}harvard.edu