In the 1930s, one of the earliest studies to demonstrate the importance of the environment for child development showed that when institutionalized children with low IQs were moved to an institution for “feeble minded women,” their IQs improved to the normal range. The apparent mechanism was that the women enjoyed interacting with the children. However, the findings were strongly contested by eugenicists.1 

There is now overwhelming evidence that poverty and associated factors in early childhood affect children’s development. Key factors include poor growth, unstimulating home environments, low parental education, and poor maternal mental health.24  Deficits in development are evident from the first year of life and increase at least up to age 6 years.2,5 

Parenting programs that focus on promoting responsive interactions and opportunities to learn benefit children’s development, and children in low and middle-income countries (LMIC) benefit more than those in high income countries (HIC).6  In HIC, benefits often fade after intervention ends,7  although follow-up of high quality studies shows benefits, such as increased high school graduation and wages,8  and an intense, long term intervention showed changes in brain structure in adulthood.9  Few interventions in LMIC have been followed up beyond age 5 years.10  The only adult follow-up found wide-ranging benefits up to 31 years11,12  and more long-term studies are needed.

Considering the enormous loss in children’s developmental potential and the availability of successful early childhood development (ECD) interventions, there is consensus that it is urgent to deliver ECD programs at scale.13,14  In moving to scale it is essential that only effective programs, feasible at scale, are advocated. Low intensity and short interventions may have initial small benefits unlikely to be sustained. If governments are persuaded to invest in ECD programs, they must deliver worthwhile gains.

Child development programs are complex, so universal standardization is probably not appropriate, and adaptation to local context is essential.15  Meta-analysis of studies using the same ECD curriculum (Jervis et al, this supplement16 ) found impacts on child development varied substantially, indicating the importance of implementation processes and target population characteristics.

Critical to planning for scale is determination of potential systems for delivery and resources and modifications necessary for successful implementation. Health systems are often proposed as they reach children below 3 years and there is evidence that with sufficient training, supervision and allocated time, community health workers can successfully deliver ECD programs.17,18  However, health systems are often under-resourced and substandard in important aspects of child care.19  Adding another program to an over-stretched, underperforming system and expecting health workers to deliver ECD activities in addition to their usual workload is unlikely to be successful. In almost all cases, some new staff and resources with sustainable funding is essential. More exploration is needed of scaling through other systems or dedicated ECD services and innovations to support implementation quality. Evidence is also needed on the impact of increasing program aims and topics on facilitator capacity to deliver and acceptability and effectiveness for parents. We suspect that effectiveness is reduced when many topics are included.

Before scaling, programs should be piloted at moderate scale to confirm they remain effective, and to identify adjustments needed in implementation. Avoiding too rapid roll out20  by phasing in the program with continued monitoring and adjustment may increase success. Findings of no impact can identify problems, such as existing workload21  or insufficient supervision and support for delivery staff.22  Negative findings are sometimes not published, which is unhelpful and prevents learning from results.23 

A key goal of ECD programs is to reduce the disadvantages faced by children growing up in poverty.24  However, access is not equitable. For example, access to preschool in LMIC averages 20% of eligible children with wide disparities within countries; wealthier children having better access to better preschools.25  Paradoxically, both parenting16  and preschool programs26  benefit disadvantaged children most. ECD policies and expansion of programs need to prioritize access by those most in need.

There is need for feasible assessments to track country progress and program benefits. The validity of measurements developed for this purpose is critical. These include the ECDI2030,27  the Sustainable Development Goal indicator for ECD, and the Global Scales for Early Development, designed for use at population and group level, with culturally neutral, easy to administer items. Item difficulty derived with data from 31 countries, predominantly LMIC, was used to produce an underlying scale or developmental score.28 

Despite the increase in ECD research in LMIC, there remains insufficient work led by researchers living and working in LMIC. Where these researchers are involved, studies are usually led by HIC academics. Attempts at capacity building have been made, but often ignore the limited research funding available in most LMIC. Thus, developing productive sustainable groups of child development researchers remains a challenge. Although a few funding agencies have targeted LMIC researchers, others require HIC coinvestigators. Junior researchers in LMIC often do not have access to advantages available to students and postdocs in HIC universities through faculty connections, financial support for research degrees, and in many cases, access to research conducted in LMIC for analysis. Sustainable ECD programs at scale require in-country professionals to champion and support their execution.

There is increasing recognition that nurturing care needs to extend beyond early childhood to primary school-aged children and adolescence.29  It is distressing that over 50% of children in LMIC cannot read at 10 years even when in school.30  Children lacking ECD services are disadvantaged on school enrolment, reducing their school success, whereas without attention to primary school children, the long-term benefits of ECD programs may not be realized. Finally, there is still much work to do to increase demand by governments, communities, and parents for ECD services. We need to use all avenues to communicate the devastating effects of poverty on children’s development and advocate for interventions.

We thank Dr Jacqueline Coore-Hall for assistance with preparation of this commentary.

FUNDING: No external funding.

CONFLICT OF INTEREST DISCLOSURES: The authors have no conflicts of interest relevant to this article to disclose.

ECD

early childhood development

HIC

high income countries

LMIC

low and middle-income countries

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