Evaluating the impact of stimulation and micronutrients on early childhood development

21 July 2012

The preliminary results and analysis of this study was presented at the Promises for Preschoolers: Early Childhood Development and Human Capital Accumulation conference on 25 June in London.

The first few years of life are a period of intensive brain development. It is in this crucial phase that we form cognitive and social skills that last through an entire life span.  Preliminary results from an impact evaluation in Colombia suggest that regular visits from a well-trained but local “home visitor” had significant impacts on children’s cognitive development.  Moreover, this approach produced a significant impact on the receptive language and some behavioural indicators of children who were relatively older at the start of the intervention.  The same results also indicate some important effects on parenting practices.

It is an accepted truth that well-designed interventions targeted during the early years can have long lasting impacts. However, moving from such a realisation to the delivery of sustainable and cost-effective policies is a complex process. The behaviour of parents, the links of the family unit with the community, and child rearing practices that improve interactions with the parents and lead to more and better investments in child development must all be taken into account.

We designed, implemented and tested a programme in Colombia with the explicit aim of offering a blueprint for such a scalable intervention.  We wanted to address these challenges as well as generate data that allowed us to learn in a deeper and more scientific fashion.

An innovative approach to early childhood development

This Colombian programme was targeted at poor households with children between 1 and 2 years of age. The intervention was conducted in 96 small towns and covered around 1,500 households in total. The households we studied were beneficiaries of a large Colombian cash transfer programme called Familias en Acción.

Integral to this intervention was a stimulation programme, which consisted of weekly home visits from a “home visitor” to a mother and child that lasted an hour and that were carried over a period of 18 months. A key innovation of the programme was that the home visitors were drawn from a network of local women who were mediators between beneficiaries of the cash transfer programme and the government. They were thus both influential and well connected within their own communities. The home visitors received training and advice from mentors with backgrounds in psychology or social work. Having home visitors based in the communities helped minimise costs and facilitated implementation. This innovation also carried with it the promise that local communities would feel empowered to take ownership of the intervention going forward.

The home visitor interacted with mother and child on the basis of a well-structured but flexible curriculum. The curriculum focuses on cognitive and linguistic development and includes age-appropriate activities eg songs and nursery rhymes, toys (constructed from everyday domestic materials), books and puzzles. More generally, there is an emphasis on fostering interaction between mother and child on a continuous basis, and on integrating two-way conversation, praise and play into regular day-to-day activities.

The second arm of the intervention also included a micronutrient supplementation component: provision of iron, zinc, Vitamin A and Vitamin C in levels appropriate for long-term intake by children.

A key goal of this study was to evaluate the effect of the programme on children’s cognitive, linguistic and motor development. We also studied the way household behaviour changed in reaction to the stimulation and micronutrient supplementation.  While we found that the home visitor element produced significant improvements in both cognitive development and the quality of the home environment, we detected limited impacts of micronutrient supplementation.

Orazio Attanasio, University College London, Centre for the Evaluation of Development Policy (EDePo) at Institute for Fiscal Studies (IFS)

Emla Fitzsimons, Centre for the Evaluation of Development Policy (EDePo) at Institute for Fiscal Studies (IFS), London, UK

Sally Grantham-McGregor, University College London

Costas Meghir, Centre for the Evaluation of Development Policy (EDePo) at Institute for Fiscal Studies (IFS), London, UK and Yale University

Marta Rubio-Codina, Centre for the Evaluation of Development Policy (EDePo) at Institute for Fiscal Studies (IFS), London, UK

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