A critical challenge within early childhood policy is to increase the capacity of early childhood education and care systems to intervene effectively and sufficiently early to improve the learning and development outcomes of marginalised children. An initial step is to reliably identify young children at risk of poorer learning outcomes. This…

In the 1998 reauthorization of Head Start, Congress mandated that the US Department of Health and Human Services (DHHS) determine, on a national level, the impact of Head Start on the children it serves. As noted by the Advisory Committee on Head Start Research, this legislative mandate required that the impact study address two main research…