Global early childhood development services remain fragmented despite broad agreement on their importance
Early childhood development ECD services sit at the intersection of child health, developmental surveillance, caregiver support, and social protection. This BMJ Open scoping review mapped how those services are being designed and delivered for children under 5 years of age, including healthy children, those at risk of developmental difficulties, and children with established disorders. The central finding is simple and consequential: the evidence base is large, diverse, and still unevenly distributed across the world.
Across 271 included studies, service delivery tended to cluster around hybrid models rather than single-channel care. Multicomponent interventions delivered by multidisciplinary teams were common, with health professionals and community health workers frequently working side by side. In practice, that combination reflects a familiar reality in child development care: no single discipline can meet the nutritional, behavioral, psychosocial, and functional needs that emerge in early life. Care has to travel across clinic walls, family systems, and community settings if it is going to reach children before developmental delay becomes entrenched.
The review identified 10 core service components. Family-centred and integrated approaches appeared repeatedly across populations, suggesting that ECD programs are moving away from narrow, condition-specific support toward broader models that include caregivers, coordination across sectors, and attention to the home environment. For infants and preschool-aged children, those elements are not decorative add-ons. They are often the mechanism through which developmental surveillance becomes actionable, because caregivers are the people who see language delay, motor asymmetry, or social communication concerns first.
One striking pattern ran through the literature: most studies came from high-income countries, while low-income settings were sparsely represented.
Workforce capacity and service integration drive the strongest implementation signals
The review organized barriers and facilitators into eight thematic categories spanning workforce, organizational processes, infrastructure, policy, and cultural factors. That structure matters because ECD services fail for reasons that are often operational rather than biological. A screening tool may be valid, but if trained staff are unavailable, referral pathways are weak, and follow-up depends on fragmented records, the child never reaches intervention. The review’s mapping places these implementation constraints at the center of the policy discussion.
Hybrid delivery models likely gained traction because they can absorb some of that complexity. Community health workers can extend reach into underserved neighborhoods, while clinicians contribute diagnostic expertise, supervision, and escalation when a child needs specialized assessment. In many settings, that division of labor is the only realistic way to deliver early intervention at scale. It also helps explain why interventions were frequently associated, descriptively, with better child developmental outcomes, improved caregiver well-being and knowledge, stronger provider competencies, and more coordinated intersectoral work.
Those associations should be read carefully. The review did not undertake formal quality appraisal, and its descriptive design does not permit causal inference or direct comparison between program models. Even so, the pattern is clinically meaningful. When caregivers understand developmental milestones, providers have usable tools, and systems support continuity, the chance of early identification rises. When those pieces are missing, delays are often recognized late, when the window for low-intensity intervention has narrowed.
Low-resource settings need adaptable packages, not imported templates
The review’s most policy-relevant message concerns equity. Evidence from low-income countries was limited, yet the need for ECD services is likely greatest where poverty, undernutrition, limited access to specialists, and weak referral systems converge. A service package built for a well-resourced urban system may not translate cleanly into that environment. The literature mapped here repeatedly points toward contextual adaptation as a prerequisite for scale-up, not an optional refinement.
This is where the biological and social logic of early development converge. Brain growth, language acquisition, attachment formation, and motor learning unfold rapidly in the first 5 years. Missed opportunities in that period can alter later school readiness, behavior, and family functioning. Services that combine surveillance, caregiver coaching, developmental promotion, and referral are designed to intervene early enough to change that trajectory. Their effectiveness in real-world settings depends on whether they are made culturally acceptable, logistically reachable, and financially sustainable.
Because the included studies were heterogeneous, the review does not produce a single best model. It instead offers a map of recurring ingredients: family-centred care, integration across sectors, multidisciplinary staffing, community engagement, and flexible delivery. Those ingredients can be assembled differently depending on local disease burden, workforce mix, and financing structures. A rural primary care network will not need the same configuration as a tertiary urban system, but both need a pathway that turns developmental concern into action without delay.
The evidence base is broad, but the field still lacks comparability
The review searched major biomedical databases, regional databases, grey literature sources, and trial registries, with the final search updated to 31 December 2025 before finalization. That breadth strengthens the mapping exercise and makes the evidence base more credible as a policy resource. It also reveals how difficult it remains to compare programs across countries and service platforms. Definitions of ECD services vary, delivery models differ widely, and outcomes are reported with inconsistent depth.
Those limitations are not minor. Without common reporting standards, it becomes hard to separate a program’s core design from the local conditions that support it. A model may appear effective because it is embedded in a strong health system, not because the intervention itself is inherently superior. The scoping review avoids overclaiming, which is appropriate for a field still building its descriptive foundation.
For policymakers and program planners, the value lies in the map itself. It identifies where evidence is concentrated, where it is thin, and which service components recur across settings. It also makes clear that workforce strengthening, contextual adaptation, and policy support are not abstract priorities. They are the conditions that determine whether early childhood development services reach children early enough to matter.