Does a Home Visiting Program in Early Childhood Have Sustained Effects on Development Two Years After It Ends? Evidence from Colombia

October 3, 2016

In Colombia, researchers will evaluate the medium-term effects of a home-based early childhood development intervention. The program seeks to improve nutrition and development in the first two years of life through home visits to encourage children’s psycho-social development and use of micronutrient supplements. The findings will be used to help policymakers and others understand the extent to which nutrition and parental involvement at an early age carry lasting effects into the medium term and how such programs can be scaled up effectively.

Research area: Early Childhood Nutrition, Development, and Health

Country: Colombia

Evaluation Sample: 1,429 children 

Timeline: 2012 - 2015

Intervention: Psychosocial stimulation, home visits, micronutrient supplementation

Researchers: Orazio Attanasio, University College London and Institute for Fiscal Studies; Emla Fitzsimons, Institute for Fiscal Studies and Institute for Education; Emanuela Galasso, World Bank; Sally Grantham-McGregor, UCL Institute of Child Health; original researcher in the Jamaica study; Costas Meghir, Yale University and Institute for Fiscal Studies; Marta Rubio-Codina, Institute for Fiscal Studies, London; 

Development experts and educators know that stimulation programs for very young children are important to development and school readiness. Verbal interaction boosts vocabulary and mental development; playtime builds important physical and mental skills; and praise from a parent creates confidence and security.  As shown by the long-term study of children in Jamaica whose mothers received weekly home visits by trained health workers who showed them how to play and talk to their toddlers (read the Evidence to Policy note on the evaluation), gains go beyond better grades. Nearly 20 years later, the children -- now young adults -- were earning as much as their non-disadvantaged peers. What’s not known is how to structure these programs so that they are cost-effective and still deliver the right impact, and whether linking programs with nutritional supplements or nutritional education is important. 

This project, a follow-up evaluation of a pilot intervention that delivered psychosocial stimulation and micronutrient supplements at scale in Colombia, will help policymakers and development experts around the world improve the design of cost-effective and scalable strategies for successful early childhood development programs.


Researchers piloted an 18-month early childhood intervention for poor children in 96 semi-urban municipalities in Colombia in 2010-2011. Mothers of young children received weekly home visits in which they were taught how to play and talk to their children. Some also received nutritional supplements for their children, while one group received nutritional supplements alone. The intervention used the infrastructure of the country’s existing conditional cash transfer program for the country’s poorest, Familias en Acción, to target families and deliver the services.

The first follow-up survey in 2011 showed that the stimulation led to gains in children’s cognitive development and in receptive language skills (which refers to the ability to understand and process one hears or reads). The micronutrient supplements had no significant effect, neither alone nor when paired with the stimulation.

This second follow-up survey will measure whether the gains were maintained two years after the program ended. If the results are positive, this model for delivering stimulation could serve as a promising blueprint for future policy on early childhood development.

Photo: World Bank

Intervention and Evaluation Details


The initial intervention ran from 2010-2011 in three regions in Colombia.  Thirty-two municipalities of between 2,000 and 42,000 inhabitants in which Familias en Acción was operating were identified in each region for the cluster level randomization. The municipalities were randomly assigned to one of four groups: one group received weekly home visits to encourage psychosocial stimulation for children aged 12 months to 24 months; one group received biweekly distributions of micronutrient supplements for daily consumption for all children under the age of six; one group received both; and one group was the control and received nothing. There were 24 treatment clusters for each of the four groups, with at most 15 children per cluster, for a total of 1,429 children enrolled and tracked in the program.

To qualify for the 18-month program, families had to have children aged 1-2 years old and be in the government’s Familias en Acción program. The home visits were carried out by local women who already worked as mediators between Familias en Acción and beneficiaries, so they knew the families and were trusted. These women were hired and trained in how to carry out weekly home visits to demonstrate to mothers play activities using low cost or homemade toys, picture books, and form boards, among other materials. These materials were left in the homes for the week after the visit and were changed weekly. The aims of the visits were to improve the quality of maternal-child interactions and assist mothers to participate in developmentally appropriate learning activities, many centered on daily routines. The home visitors received mentoring every few weeks from professionals, and constant telephone support.


This follow-up evaluation will identify the medium-term impact on children two years after families stopped receiving the visits by measuring the children’s development skills. At the time of the second follow up (September-December 2013) the children would be between four and a half and five and a half years old, and about to enter primary school. Tests will focus on cognitive, language, and socio-emotional development. Researchers will also survey mothers on their knowledge of appropriate child stimulation and measure any positive spillover effects on younger siblings.

Policy Impacts

This research has the ability to improve understanding of how to provide mothers of young children assistance that can boost development. It can also provide information on how do so in what could be a cost effective manner. (The cost was $515 per year per child, of which half was for the mentoring provided to the community women who carried out the home visits).With governments around the world eager to improve the lives of their youngest citizens, finding an affordable way to deliver early childhood stimulation at scale is critical to success.