The importance of early life has been highlighted in three series on Early Childhood Development (ECD) published in The Lancet between 2007 and 2016 and in many other publications. One of the key conclusions of this burgeoning literature is that stimulation interventions can be life-changing with long-run persistent effects leading to tangible improvements in quality of life through adulthood. There have been an increasing number of studies, including randomized trials, of interventions (typically based at home) during the first life-cycle stage, from pregnancy to 2 years or interventions (often center-based) during the second life-cycle stage (3 to 5). Ultimately, the aim of such interventions is to break the intergenerational transmission of poverty and to offer equal opportunity to all. However, there are three critical questions outstanding:
(i) how to design scalable ECD interventions that can reach broad segments of poor populations in an effective and sustainable way and lead to longer-run impacts,
(ii) at what stage should one intervene in a child’s development and for how long, and
(iii) can such approaches be adopted effectively in the contexts of rural South Asia, wherein live almost half of the world’s children under 5 years of age who are predicted to not reach their developmental potential.
To answer the questions above about optimal timing requires however a randomized design at both the earliest and the next stage. In this study we implement the second phase of such a design in 192 villages in rural Odisha (India), with randomized curricular improvements for the pre-school stage (ages 3-5 years) overlaid on a completed randomized intervention to improve parental stimulation during the first 1-3 years of life. With such a design, some children will be exposed to our interventions in both the first 1-3 years of life and when 3-5 years old, some children will be exposed in one or the other of these two age ranges, and some will not be exposed at all, but will of course have access to whatever is currently provided in these communities by the government or the private sector. Odisha provides an excellent setting for the study as it represents a prototypical context of low levels of stimulation, high malnutrition, poor developmental outcomes and extreme levels of poverty. Only with such a design can we confidently learn answers to the critical questions about timing that are raised above.