Early childhood interventions show mixed results on child development

Previous work has suggested that early childhood interventions -- those focused on the first 1000 days of life -- have the potential to offset some negative impacts of adversity on child development. In one new study, Peter Rockers of Boston University, USA, and colleagues followed 526 pairs of children and caregivers in a cluster-randomized trial done in Southern Province, Zambia. All children were 6 to 12 months of age at the start of the study. 258 pairs received no intervention, while the other 268 were visited twice a month by a Child Development Agent, to monitor the child's health, and invited to attend twice monthly parenting group meetings, where they learned a diverse parenting curriculum.

After two years, children who had been in the intervention group were less likely to show signs of stunting and scored higher on measures of language, but the intervention did not significantly impact cognition, motor skills, or adaptive behavior. "In settings like Zambia, where optimal child nutrition and stimulation are often lacking, parenting groups hold promise for improving child health and welfare," the authors say. "However, improvements in child development may not be immediate and continued and sustained efforts are likely needed."

In a second paper, Alison Andrew of University College London, UK, and colleagues randomized 1419 children aged 12-24 months, living in 96 towns in Colombia, to receive either no intervention, participation in a home visit program, micronutrient supplementation, or both of the latter interventions. Home visits followed a structured curriculum, with an emphasis on cognition and language, and the goal of increasing maternal-child interactions. After two years, the researchers found no effect on cognition, behavior, or home stimulation. "It is possible that the initial effects on child development were too small to be sustained or that the lack of continued impact on home stimulation contributed to fade out," the authors write.

In an accompanying Perspective, Mark Tomlinson of Stellenbosch University, South Africa, discusses the challenge of determining why the effects of early interventions may fade out by middle childhood. "In contexts of high risk and adversity the impact of early interventions may be more durable when they are built upon by interventions during later years," he writes. Scaling up these interventions also requires more work, he adds, noting that some interventions are not scalable in their current form. "Looking to the future, the early childhood development field requires rigorous implementation science research that examines the best models... to achieve impact."