Early Childhood Programs
Early childhood extends from the prenatal period to approximately 8 years of age.1 The brain develops rapidly during this time, making it especially vulnerable to external environmental influences, particularly during the first 3 years.1 Consequently, factors such as family and societal connectedness, access to health care and adequate nutrition, economic and educational influences, and heritable or acquired medical conditions can significantly impact a child’s early development and future endeavors and accomplishments.1 It was reported to an estimated 8.8 percent of children in the United States, aged 0 to 5 (and 16 percent of children aged 6 to 11), were at risk for, or suffered from, developmental needs requiring additional health care and other related services.2 On a global scale, the World Health Organization estimates that every year over 200 million children under age 5 fall short of achieving their full intellectual and social capabilities.1 If such deficits and the factors that contribute to them are left unaddressed, they not only affect individual children but can carry forward to future generations.1
Early childhood programs strive to identify and support at-risk children by addressing physical and cognitive limitations, early education and social development, access to health care and community services, access to adequate nutrition, and environmental safety to promote optimal development.1 Early childhood programs may also address the needs of parents by providing education, parenting skills, and other types of social support.1 This report summarizes findings from systematic reviews of early childhood psychosocial interventions focusing on cognitive, behavioral, and socioemotional outcomes. Two populations in particular emerged in this report: (1) children from low socioeconomic backgrounds and (2) children diagnosed with pervasive developmental disorders (PDDs), a group of disorders characterized by impairments in social, communicative, and behavioral skills.3 PDD, often used synonymously with autism spectrum disorder (ASD), includes autistic disorder, Asperger’s syndrome, PDD not otherwise specified (PDD-NOS), childhood disintegrative disorder, and Rett syndrome.3, 5 These two critical populations represent a substantial percentage of children living in the United States. Reports showed that 21.3 percent of U.S. children under age 6 were living in poverty,4 a sampling from communities across the United States estimated 1 in 110 children, aged 8, suffered from a PDD.5
Search Strategy and Criteria
An extensive search was conducted for systematic reviews published. The search was limited to the online catalog of the U.S. Government’s National Library of Medicine, PubMed to ensure free access to abstracts, and in some cases, full-text articles. Systematic reviews reported in the context of guidelines, consensus statements, or studies were not the target of the search.
The strategy to conduct the search was as follows: “Early Intervention (Education)”[Mesh] AND (systematic[sb] OR Meta-Analysis[pt]) AND English[lang] AND "Humans"[MeSH Terms] AND [PDAT]: [PDAT]
Each part of the strategy is described below:
- Topics: The Medical Subject Heading “Early Intervention
(Education)” used in the search is defined by PubMed as “procedures and programs
that facilitate the development or skill acquisition in infants and young children
who have disabilities, who are at risk for developing disabilities, or who are gifted.
It includes programs that are designed to prevent handicapping conditions in infants
and young children and family-centered programs designed to affect the functioning
of infants and children with special needs.”
- Additional limits: Limits were used restricting the search to systematic reviews (with a separate designation for those containing meta-analyses) and articles published in English, focused on humans. The search was further narrowed by hand-selecting reviews focusing on early childhood psychosocial interventions with primarily cognitive, behavioral, or socioemotional outcomes. Age-range criteria were somewhat flexible; however, reviews that extended into adolescence or adulthood and that precluded assessment of early age groups were excluded.
The literature search yielded a total of six systematic reviews. Of the six reviews, three included a meta-analysis (Reviews 3, 5, and 6). The average number of studies included in the systematic reviews was 12 (range = 9–16). Studies were conducted in the United States and internationally. Settings for the early childhood interventions were not reported for all studies, but those that reported settings included participants’ homes, preschools, and the community. Two systematic reviews focused exclusively on examining the effect of early childhood programs on cognitive, social, and health outcomes in low-income or disadvantaged preschool children (Reviews 1 and 2). The remaining four reviews (Reviews 3–6) assessed the effect of early childhood interventions on the cognitive and behavioral outcomes of children diagnosed with a PDD, including autistic disorder, Asperger’s syndrome, and PDD-NOS. Three of these reviews (Reviews 3, 4, and 6) focused on early intensive behavioral interventions (EIBIs). EIBIs are comprehensive intervention programs for children with autism that are individualized and use many behavior analytic procedures to build new repertoires and reduce interfering behaviors. The interventions are initially delivered one-on-one, often starting in the home, with a gradual transition to groups in community settings. Parents serve as active cotherapists, and normal developmental sequences guide the selection of intervention goals. The programming is intensive (20–30 hours per week plus informal instruction during the remaining time) and year-round. Most EIBIs last 2 or more years.
Early Childhood Interventions for Children With a PDD
EIBIs are very effective in improving the intellectual functioning and adaptive behaviors of children diagnosed with PDDs (Reviews 3, 4, and 6). Children receiving EIBIs made more gains in expressive and receptive language than children receiving eclectic treatment, minimal behavioral intervention, or treatment as usual (Review 6). There is wide variability in children’s response to EIBIs, and intelligence quotient (IQ) and initial language level appear to be related to children’s outcomes (Review 4). There are also indications that the first year of participation in EIBIs produces the most gains in IQ, with the impact of EIBIs decreasing over time (Review 4). Parent-implemented interventions, where the parents serve as cotherapists for their children with a PDD, improve children’s social communication skills (Review 5). Parent-implemented interventions improve parent-child interactions, increase parental knowledge of autism, and reduce parental stress.
Early Childhood Interventions for Low-Income Children
Early childhood programs (e.g., Head Start, Perry Preschool Program), administered when children were between the ages of 0 and 9 years, had lasting positive effects for the participants (Reviews 1 and 2). Specifically, low-income children who participated in early childhood programs between the ages of 3 and 5 demonstrated improvement on standardized measures of academic achievement, school readiness and IQ, and reduced grade retention and placement in special education classes (Review 1). However, there was insufficient evidence to determine the effectiveness of the programs on children’s behavioral and social outcomes. Early childhood programs for disadvantaged children (e.g., Head Start, Chicago Child Parent Center, Perry Preschool) also have a lasting effect on the health outcomes of participants well into adulthood, such as tobacco and marijuana use, exercise, and safety behaviors, but not chronic disease outcomes.
In sum, EIBIs and parent-implemented interventions were successful in improving the IQ, language skills, and adaptive behavioral skills of young children with a PDD. Early childhood interventions for low-income children significantly improved the cognitive and health outcomes in low-income children years later. Systematic reviews examining the social and behavioral outcomes of young children are too sparse to determine the effectiveness of early interventions on children’s social development.