Quality early childhood education for under-two-year-olds: What should it look like? A literature review
Recent years have seen increasing participation of under-two-year-olds in early childhood education. This literature review draws together relevant research evidence to better understand what quality early childhood education for children under-two-years of age should look like.
Author(s): Carmen Dalli, E. Jayne White, Jean Rockel, Iris Duhn with Emma Buchanan, Susan Davidson, Sarah Ganly, Larissa Kus, and Bo Wang, Victoria University of Wellington.
Date Published: March 2011
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Chapter 6: Narrative review of the effects of high quality centre-based early childhood education and care on the developmental outcome of at-risk children
This chapter reviews recent reports about the effects of early intervention programmes for children living in adverse conditions, including poverty, low income families, and prenatal exposure to cocaine. The programmes reviewed are the Abecedarian project and Early Head Start based in the USA and Sure Start, based in the UK. The chapter focuses on highlighting elements of the programmes found to be associated with positive developmental outcomes for children and families; these are summarised at the end of the chapter.
The focus in this chapter is on quantitative studies published over the last decade that have reported results about the effects of quality centre-based early childhood services during the first two years of life on children considered "at risk". Most of these are early intervention studies in which data have continued to be gathered longitudinally until young adulthood (e.g., at age 21 years within the Carolina Abecedarian project).
Three key longitudinal projects with at-risk populations were identified as relevant to the age group covered by this review. Two of these were conducted in the USA: (i) the Abecedarian project; and (ii) Early Head Start. The third longitudinal study, the Sure Start project, is based in the UK12. All three are described as intervention studies with children from disadvantaged or "deprived" (Melhuish et al., 2008a, p. 1641) backgrounds (low income families in high poverty neighbourhoods) enrolled in programmes designed to promote health and development, improve children's educational chances, and reduce inequality.
Also included in this chapter is a selection of studies from outside these longitudinal programmes that have investigated the effects of quality childcare on 0–2-year-olds considered at risk of poor developmental outcomes from adverse conditions such as low birth weight, and prenatal exposure to cocaine. The latter has been a focus of interest in many studies as maternal drug use is associated with collective risk factors, and thus functions as a marker for an early-identifiable at-risk population (Bolzani Dinehart, Yale Kaiser & Hughes, 2009).
Although, as Melhuish et al. (2008b) have noted, "studies with disadvantaged populations may have little relevance for the general population" (p. 1161), this selection of studies is included in this report because this area of research was deemed of interest to the Ministry in the commissioning of this report.
No specific New Zealand intervention studies with under-two-year-olds were identified in the systematic search conducted for this literature review.
A key focus of this chapter is to highlight the elements of the programmes found to be associated with positive child and family impacts.
6.1 Interventions with children living in poverty
The Carolina Abecedarian project, Early Head Start and Sure Start have all worked with children living in poverty; each has reported results over the last decade that indicate the positive effect of intervention through the use of centre-based early childhood services accompanied by other support services for families.
6.1.1 The Carolina Abecedarian Project and the Carolina Approach to Responsive Education (CARE)
The Carolina Abecedarian project remains one of the few model programmes that was delivered in a full-time childcare setting which was open all year round from early morning to late afternoon. It was a randomised trial that involved 111 infants enrolled in four cohorts between 1972 and 1977. The children were from low-income families of primarily African-American background, with eligibility determined on the basis of a High Risk Index (Ramey & Smith, 1977, cited in Campbell & Pungello, 2000). Of these, 57 were randomly assigned to receive (centre-based) early educational intervention, and 54 were the control group (no intervention). The parents of the participant children had to agree before the start of the project to the condition of random assignment; the control group became known as the "milk and pampers" group as families within it received iron-fortified formula and free disposable nappies for the first 15 months of the study; the formula was to control for differences in the nutrition of the children, and the nappies were an incentive for participation. Children within the "treatment" group received free full-time childcare all year. When the children entered state kindergarten the treatment and control groups were each split into two; of the four resulting groups, two received additional educational support from a home-school resource teacher. Campbell and Pungello explained that in the three intervention groups:
...us varied in timing and duration from 8 years in preschool and early elementary (EE group), to 5 years in preschool only (EC group), to 3 years in early elementary school only (CE group). When long-range outcomes are discussed they may be examined as a function of either the preschool (2-group) assignment originally made or in terms of the four-group assignment made at kindergarten entry. (p. 7)13
The Carolina Approach to Responsive Education (CARE) was a second study that expanded on the Abecedarian research by modifying the early intervention treatment to include (i) weekly home visits from the child's teacher for children within the centre-based treatment group; and (ii) an intervention group where children received home visits but no centre-based early childhood education. The no-treatment control group was maintained (Campbell, Ramey, Pungello, Sparling & Miller-Johnson, 2002; Campbell et al., 2008). The participants in CARE were born between 1978 and 1980 with half the spaces in the programme reserved for low-risk infants to ensure more diversity in the childcare centre during the project. This resulted in smaller numbers of children at the centre who met the high-risk criteria with the result that: (i) the centre-based and home-visits intervention had 16 families participating; (ii) the home-visits intervention without centre-based childcare had 25 families; and (iii) the control group (no intervention) had 23 families. The main factor on which the participants in the Abecedarian and CARE participants differed was the higher average education level of the CARE mothers; the percentage of teen parents was 31–68 percent across both studies.
Ramey et al. (2000) described the Abecedarian project as a "comprehensive education, healthcare and family support program that provided an individualised approach to at-risk children and their families, drawing as needed on a pool of available resources" (p. 4). Children attended the centre from infancy with the average age at entry being 4.4 months; the youngest child in the study started at six weeks.
Characteristics of the centre-based intervention (ages zero to five years)
Summarising the characteristics of the original centre-based childcare programme received by the children in the Abecedarian treatment group (2-group design), Campbell and Pungello (2000) reported the following:
- caregiving staff who from infancy were seen as "teachers" (p. 5)
- curriculum activities called learning games (p. 5) that were specifically designed for the Abecedarian project to target language, cognitive, motor, and social-emotional development; these were systematically assigned to each infant, toddler or preschooler
- the regular presence of one of the developers of the curriculum activities at the childcare centre working with the teachers to assign learningames and deciding when the children were ready for new ones
- an eclectic curriculum model that included both child-directed and teacher-directed activities
- child-staff ratios14 that exceeded the minimum requirements within the state of North Carolina
- daily availability of medical staff (primary pediatric care) to ensure child well-being and to counsel parents on developmental milestones and childcare
- virtually no turnover of staff
- staff salaries at a level comparable to teachers in public elementary schools.
Commenting on the salary levels of the staff, Campbell and Pungello (2000) credited them as the reason for the low staff turnover and with greater stability in the children's lives. They noted also that all staff were highly experienced and all came from the same background of the children with some staff qualified at degree level.
Effects of intervention on children
Children in the Abecedarian project were periodically assessed during the early childhood and primary school grades, and home visits at 6, 18, 30, 42 and 54 months of age were done to evaluate parent and child interactions, available toys and educational materials, parental support for the child's learning, stability of family routines, and the variety and breadth of stimulation available to the child. In a series of articles published between 2000 and 2008, the results of follow-ups between the ages of 3 years and 21 years indicated better outcomes for the childcare treatment group in comparison to the control group. For example, Campbell and Pungello (2000) found better results for the treatment group in the two-group study:
- on tests of cognitive functioning
- in mathematics scores
- in rates of being at school at age 21
- in having attended a four-year college
- in being a year older when their first child was born.
There were no differences in rates of high school graduation and employment; and, likewise, no reduction in law breaking that could be associated with having been part of the Abecedarian project.
The earlier results from the same projects had indicated that centre-based early educational intervention significantly increased children's performance in early childhood intellectual tests, both in the Abecedarian and CARE studies, as well as academic outcomes at age 8 years (Burchinal et al., 1997).
The pattern of positive effect on children's cognitive and academic achievement differences from the centre-based treatment was evident also in the data from the four-group assignment study (Ramey et al., 2000). Additionally, Ramey et al. reported that there were positive effects on the educational attainment of the children's mothers. The authors concluded that the availability of high quality, consistently available childcare was associated with greater educational achievement for the mothers as well as higher levels of employment especially for the teenage mothers.
Persistence of effects into adulthood
The persistence of beneficial effects of the centre-based treatment on reading and mathematics skills into young adulthood were also reported by Campbell et al. (2002) together with a lower level of reported marijuana use among Abecedarians who had been part of the treatment group. Comparing the outcomes of the Abecedarian project with the adult benefits of Project CARE, Campbell et al. (2008) concluded that the CARE results replicated the Abecedarian ones. In other words children in the centre-based treatment groups did significantly better on measures of educational and vocational attainments in young adulthood. Specifically, those adults who as children had received the full five years of centre-based early intervention in the CARE programmes, by comparison to the control groups, were:
- 7.06 times more likely to be in an educational programme when interviewed in early adulthood
- 3.99 times more likely to be attending a baccalaureate college
- 1.95 times more likely to be in skilled employment relative to those who had not received the treatment.
Campbell et al. (2008) further reported that there were no significant educational and vocational benefits for the home-visits/family-education only group compared to the control group, a finding that surprised them and which they hypothesised might be attributable to insufficient intensity or comprehensiveness of the home-visits/family-education treatment.
Summarising the significance of their findings, Campbell et al. (2008) noted that:
The results show that early childhood programs can make a lasting difference in the lives of poor children. (p. 464)
These longitudinal studies demonstrate that some of the most important societal gains to be realized from early childhood programs may not be seen until late adolescence or early adulthood. (p. 464)
Economists have estimated that the program should return approximately $3.66 for every dollar spent on the preschool program. (p. 464)
Commenting on the implications from their study, Campbell et al. (2008) make the following statements:
Money spent on quality early childhood education for poor children pays off with long-term educational and vocational benefits. (p. 464)
Teachers of the very young should be fully aware of the importance of their task. What they do in their classrooms can have long-term positive effects on the lives of the children in their care, especially for children growing up in low-income households. (p. 464)
6.1.2 Early Head Start (EHS)
Early Head Start was set up through legislative action by the United States Congress in 1994 as an extension of Head Start, the compensatory early education programme initiated in 1965 as a targeted provision for four-year-olds. EHS was a response to growing awareness of the important role of the first three years of life (Gray & Francis, 2007). It has been described as a "national laboratory for responding to the unique needs of low-income15 infants, toddlers and their families" (Chazan-Cohen, Stark, Mann & Fitzgerald, 2007, p. 100). Taking a two-generation approach, EHS projects prioritise children's development at the same time as aiming to strengthen families through a model of community collaboration. This includes provision for EHS staff to receive professional and personal support to provide "high quality environments and experiences, and engage in responsive relationships that promote the healthy development of infants, toddlers and their families" (Chazan-Cohen et al., p. 99).
Characteristics of the EHS projects
EHS operates through programmes of different designs that are either run by EHS itself or contracted to community childcare agencies as grantees in partnerships with the EHS Program (Ontai, Hinrichs, Beard & Wilcox, 2002; Paulsell et al., 2002). Three models are possible: home-based, centre-based and a combination option (Love et al., 2004). High quality performance standards developed at the start of the programme provide guidance for all three models of the program across states.16 For example, the standards issued in 1998 required:
- A staff:child ratio of 1:4, and a maximum group size of eight infants and toddlers in centre-based childcare ttings;
- Childcare staff to have a Child Development Associate (CDA) credential within one year of being hired as an infant-toddler teacher
- Draft standards within family day care homes issued in August 2000 limited groups to 6 children per teacher when two or fewer children were under age two. If more than two children were under age three, the maximum group size was four children with no more than two children under age two years.
Home-based programmes are charged to provide child development services to families mainly through weekly home visits and at least two parent-child group socialisation activities a months for each family. The centre-based programmes are expected to provide child development services mainly in centre-based childcare centres along with parenting education and a minimum of two home visits a year to each family. The combination/ mixed-approach option provides home-based and centre-based services including a combination of home visits and centre-based experiences (Love et al., 2004).
Effects of the EHS programme on availability of services for infants and toddlers in poor neighbourhoods
Reporting on the community collaborative strategies that were being implemented to improve access to the EHS programmes, Paulsell et al. (2002) identified a number of barriers for low-income families to access and maintain attendance at infant and toddler programmes, including: insufficient supply of infant-toddler services; low quality provision; high cost of services; insufficient childcare subsidies for eligible families; lack of knowledge about available services; and transport difficulties to reach services. Looking at the initiatives taken to date, the evaluation reported that a number of partnership arrangements had emerged in different communities varying from (i) comprehensive partnership; subsidy enhancement partnerships, and technical assistance partnerships. Differences in the way that the partnerships; organised their staffing, financial arrangements and intensity of technical support impacted on how the programs were implemented. Paulsell et al. concluded that the quality of infant and toddler services had improved through changes in structural arrangements of childcare such as reduced ratios and group sizes, enhanced professional development of staff, an improved curriculum, greater continuity of care and licensing of informal providers. Additionally, there was an expansion in supply of childcare services which improved access, and increased resources in the form of funding. Increased community collaboration through new relationships and improved support for services, as well as increased community awareness of early childhood issues were also considered to have improved. At the same time, tensions remained related to: improving quality and complying with the performance standards; achieving and maintaining continuity of care in a context of staff turnover; subsidy entitlements; staffing supervision issues across providers; and matching childcare arrangements to family needs.
Evaluations of EHS are ongoing. Preliminary results of an evaluation of the implementation of the EHS in 17 sites, commissioned by the Office of Planning, Research and Evaluation Administration for Children and Families of the United States Department of Health and Human Services, similarly reported that grantees often found it challenging to meet the EHS performance standards (Love et al., 2004). Love et al. focused on patterns of childcare use by EHS families and the impact of the EHS programme on families and on the quality of the childcare they used. Key findings of this evaluation were that:
- the EHS had "dramatically" (p. xviii) increased the access of low-income families to good quality early childhood services, particularly centre-based services
- the amount and quality of centre care experienced by the programme children was associated with positive developmental outcomes for the children
- there was an improved adult-to-child ratio in programme classrooms by comparison with the control classrooms measured when children were 14 and 24 months: the difference was more than one adult per child in favour of the programme classrooms.
Effects of intervention on children and parents
Reporting specifically on the effects of the EHS on three-year-old children and their parents, Love et al. (2005) highlighted that the overall effect of the programme was beneficial in a range of domains for both children and their parents. The average age of the children for whom data were reported was 5 months (with a range up to 12 months) with an average of 20 months stay in the centre-based programme.
The positive impact of EHS program consisted of:
- higher performance in children's cognitive development (measured by Mental Development Index from the Bayley Scales of Infant Development)
- higher language functioning (measured by Peabody Picture Vocabulary Test)
- fewer displays of aggressive behaviour (measured by Child Behavior Checklist) as rated by their primary caregiver – usually a parent
- higher sustained attention with play objects (i.e., the duration and quality of the child exploring and playing with toys).
Positive effects on parenting from the EHS were in the form of emotional support to the parents from the programme and support for language and learning, which make the parents in the intervention group more responsive to the child's bids for attention and more positively inclined towards the child. EHS parents also read to their infants and toddlers more than the control parents, and were less likely to have spanked their children in the week leading up to the study.
The study also found greater impact for participants in the mixed, or combined, programmes which included home- and centre-based services. When the key performance standards were substantially implemented during the early period of the projects, this increased the number and magnitude of impacts. Significant impacts in mixed programmes occurred in language and social-emotional domains (e.g., sustained attention with objects in play). The effects for centre-based programmes did not differ significantly for those in the other programme approaches on many of the child and parenting outcomes.
Overall, EHS is considered to be having positive effects on low-income infants and toddlers in the United States (Herrod, 2007). Findings from the project evaluations point to important implications about the conditions that support programme effectiveness, namely:
- having a set of programme standards was a useful mechanism to improve quality of infant and toddler services across the EHS programme
- low-income families face a range of complex barriers to accessing high quality services for their infants and toddlers, necessitating creative solutions to form programmes aimed to improve access for children from communities in poverty neighbourhoods
- community partnerships models took various forms with various challenges encountered and remaining
- community partnerships that substantially implemented the required performance standards had a bigger impact on more measures of child and family outcomes.
6.1.3 Sure Start in the United Kingdom
Established between 1999 and 2003 to improve the health and well-being of young children living in disadvantaged neighbourhoods, Sure Start Local Programmes (SSLP) were enthusiastically greeted in the United Kingdom and expanded rapidly (Gray & Francis, 2007). In 2004, the UK's Labour government's ten-year strategy for childcare (HM Treasury, 2004) stipulated a goal of 3500 Sure Start (SS) Children's Centres by 2010.
Like EHS, SS was set up as an intervention that would work through partnerships among different agencies in a local community to enable programmes to respond to local priorities through the provision of health advice and support for parents moving into employment.
Characteristics of SSLPs
As an intervention the SSLP initiative was area-based rather than targeted at specific parents or children so that all children in an SSLP area could be involved. The national evaluation summary (Sure Start, 2008) said that this was unlike almost any other intervention aimed at improving children's life chances and "had the advantage of services within a SSLP area being universally available, thereby limiting any stigma that may accrue from individuals being targeted" (p. 2). This view of the programme has not gone unchallenged both philosophically (Clarke, 2006) and in terms of the ability of the programme to reach its intended participants (Coe, Gibson, Spencer & Stuttaford, 2008).
The SSLPs had a great deal of flexibility in the way programmes were set up around the following core services:
outreach and home visits; support to families and parents; support for good-quality play, learning, and childcare experiences; primary and community health care; advice about child and family health and development; and support for children and parents with special needs, including help in accessing specialised services. (Belsky et al., 2006, p.1)
However, unlike the Abecedarian, or the EHS, there were no manualised guidelines to "promote fidelity of treatment to a prescribed model" (Melhuish, Belsky, Leyland, Barnes & the National Evaluation of Sure Start Research Team, 2008a, p. 1641).
The effects of Sure Start Local Programmes (SSLPs)
Early impact results from the SSLPs published in 2006 showed disappointing results about the value of the programmes for the most disadvantaged population they were aimed to benefit (Belsky, et al., 2006; Gray & Francis, 2007; Reading, 2006). Belsky17 et al.'s evaluation investigated the effects of SSLPs on children and their families in 150 communities with ongoing SSLPs by comparing results from home visit interviews and standardised assessments of cognitive and linguistic functioning for children with those gained in 150 comparison communities in which SSLPs were yet to be established. This quasi-experimental cross-sectional design was necessary because "the government had ruled out a randomised control trial" (Belsky et al., p. 1). The evaluation found that SSLPs benefited:
the relatively less socially deprived parents (who have greater personal resources) and their children but seem to have an adverse effect on the most disadvantaged children. Programmes led by health services seem to be more effective than programmes led by other agencies. (p.1)
Specifically, Belsky et al. (2006) found:
- that non-teenage mothers in SSLP areas showed less negative parenting than those in comparison communities, resulting in positive effects for children of non-teenage mothers in SSLP areas at 36 months, indicating fewer behavioural problems (e.g., conduct problems, emotional difficulties, hyperactivity etc.) and greater social competence (e.g., pro-social behaviour, independence)
- an adverse effect for teenage mothers. Children of teenage mothers, like those who lived in workless or lone parent households, scored lower on tested verbal ability (i.e., language expression and comprehension abilities) relative to the comparison group and relative to children of non-teenage mothers.
Belsky et al. (2006) suggested that children from relatively less socially deprived families (non-teenage mothers) benefited from living in SSLP communities, probably because of the beneficial effects of SSLPs on parenting. The authors explained that children from relatively more socially deprived families with fewer personal resources (teenage mothers, lone parents, workless households) were adversely affected because they may have been less able to take advantage of SSLP services and resources by living in SSLP areas, in comparison to socially deprived families with greater personal resources. Commenting on the results of the evaluation Reading (2006) noted that the results were both disappointing and reassuring: it was reassuring because most families benefitted (there were fewer teenage mothers than non-teenage mothers, so fewer did not benefit), but disappointing because the most vulnerable families did not.
However, more recent results (Melhuish, et al., 2008a) have indicated significantly better outcomes for children as well as their families.
Between 2004 and 2006 SSLPs changed and became Sure Start Children's Centres (Melhuish et al, 2008a; Sure Start, 2008). They specified their services in more detail with a strong emphasis on child well-being and the need to reach the most vulnerable, and with adjustment of their service provision to the degree of family disadvantage. The evaluation by Melhuish et al., (2008a) included participants affected by this change. Melhuish et al. found that after controlling for pre-existing background characteristics of children, families, and areas, and time of measurement, comparisons of children and families living in SSLP and in non-SSLP areas indicated beneficial effects for developmental outcomes of children living in a programme area. Children in the SSLP areas showed:
- better social development than those in the non-SSLP areas
- more positive social behavior18
- greater independence19
- less risk of negative parenting
- parents provided a more stimulating home-learning environment.
The (small to moderate) effects of SSLPs seemed to apply to all sub-populations and SSLP areas, with "almost no evidence of adverse effects" (Melhuish et al., 2008, p. 1605). The authors suggested that the different findings in the second evaluation might indicate an increased exposure to programmes that had become more effective. The authors repeated their comment from the first SSLP evaluation (Belsky et al., 2006) that "a randomised controlled trial would have been the strongest evaluation strategy" (Melhuish et al., p. 1646); however, they expressed confidence that the latest evaluation results indicated improvements in the programme after seven years of bedding down of the programme, increased knowledge and experience, and a reduction in staff-skills shortages. Thus the children, on whose outcome measures the report relies, would have experienced better developed programmes that in the first evaluation.
Peer responses to this second evaluation of SS were again mixed: Kane (2008) drew attention to the fact that a randomised controlled trial had not been done, but Reading (2008) noted that the research team had gone to a lot of trouble to ensure meaningful results within a quasi-experimental design, and that the results were in the long term important. The evaluation team responded that they were confident of policy implications from their findings and that they would be continuing to follow up the children and families "to determine whether at age five years, the effects detected at age three years have been maintained, dissipated, or changed in some manner" (Belsky, Leyland, Barnes & Melhuish, 2009 p. 381). Pemberton and Mason (2008), taking another tack, and using the experiences of Sure Start Children's Centres in the Greater Merseyside area, argued that not enough time had been allowed to implement and develop trust within the new arrangements and that the consequence of this might be that the needs of the most disadvantaged might not be addressed.
In summary, the studies about SS identified in this review provide a useful commentary on a different way of implementing interventions with children living in poverty in the early years. The insights from this initiative highlight a number of important points related both to the model of community partnerships, and the need to ensure that programmes are able to be evaluated in meaningful ways.
6.2 Early interventions with other at-risk populations
6.2.1 The Infant Health and Development Program (IHDP): Low-birth-weight children
The Infant Health and Development Program (IHDP) is grounded in the design and curriculum of the Abecedarian project. It was implemented in the 1980s and focused on low-birth-weight infants not only those from low-income backgrounds or from a particular racial group. Conducted at eight sites nationwide, it involved a total of 985 LBW infants divided into two weight strata: "heavier" at birth (2001–2500g), and lighter (less than 2000g) (McCormick et al., 2006).
Characteristics of the Infant Health and Development Program (IHDP)
The intervention began in infancy with home visits in the first year and centre-based care added in the second year and into the third year. Intervention outcomes at age of 36 months, 5 years and 8 years were published in the 1990s and showed that children who received the intervention had more favourable outcomes on cognitive and behavioural measures (e.g., higher IQ scores, lower behavioural problems etc.). The reports highlighted that being a LBW children asserts a higher risk of neurodevelopmental disability that may make academic achievement difficult.
Effects of IHDP on children
At 18 years old, the results reported by McCormick et al. (2006) suggested an ongoing benefit of the intervention for the heavier LBW children but not for the lighter LBW children. Heavier LBW children in the intervention group showed better reading skills and mathematics achievement, higher IQ scores, and fewer risky behaviours. Statistically significant intervention effects for children in the lighter LBW group at age 18 appeared only regarding reading scores. Earlier assessments (at three years old) of lighter LBW children had shown intervention effects for the IQ scores in favour of children in the intervention group. However, differences had disappeared by the age of five. The authors argued that the lack of observable benefits in the lighter LBW children group presents a challenge in determining who benefits most from intervention and who would need to receive continuing support for better developmental outcomes. No statistically significant differences appeared in juvenile arrest for either of the LBW groups.
Working with the same data, and using a new methodology that found a matched comparison group within the follow-up group for those with high participation rates, Hill, Brooks-Gunn and Waldfogel (2003) found "some of the first evidence that higher levels of participation in early intervention for at-risk children can result in larger and long-lasting effects than can lower levels of participation" (p. 742). They argued that the reason for the different persistence levels of the effect of participation may be lack of intensity in participation rather than other factors. They suggest that in future, studies need to focus on the gains to children's development from increased intensity of participation, and possibly also longer programme duration.
6.2.2 Interventions with children prenatally exposed to cocaine
One intervention reported over the last decade as demonstrating a positive effect on the development of children prenatally exposed to cocaine is the Linda Ray Intervention Project (LRIP) (Bono et al., 2005; Bono & Sheinberg, 2009; Claussen, Scott, Mundy & Katz, 2004). As an intervention, the programme is one described as maintaining "an ecological approach addressing family and contextual risk factors by coordinating intervention services with drug treatment and parent support without making those components mandatory" (Claussen et al., p. 207).
Characteristics of the LRIP
Using a public health model of risk-focused strategy20 the LRIP is a programme of developmental stimulation delivered at three different levels of increasing intensity (1) primary care, involving comprehensive social work services, primary medical care, and scheduled developmental assessments but no educational intervention; (2) home-based intervention, providing all primary care services plus two 1.5 hour child-focused home visits by a teacher per week; and (3) centre-based intervention, which also provides primary care services plus centre-based intervention for children for 5 hrs per day, 5 days per week. It is an ongoing long-term multi-cohort project initiated in 1993 with spaces available for 60 infants in each cohort intake; a new cohort is designated approximately every three years (Bono et al., 2005). Infants are enrolled in the intervention in their first year. In both the home-based and centre-based intervention, an outcome-based curriculum is used organised around the domains of "social/emotional, language, cognitive, fine motor, gross motor and self-help development" (Claussen et al., p. 207) either one-on-one (home-based) or in 1:3 adult:child ratio (centre-based) situations. Within the centre-based intervention, transport to and from the centre is provided, as well as a predictable daily routine including: breakfast and lunch to ensure good nutrition; nap time; small and large group activities; and taking turns at art, functional play, and symbolic play areas. To offset the impact of frequent moves and custody changes, the children are allocated to the same teachers for the duration of the intervention.
Effects of the LRIP on children
Claussen et al.'s (2004) study investigated the relative effects of the three different levels of intervention on 130 children from the first cohorts of the project. The study showed that measured at age 36months, both the centre and home-based programmes were similarly effective in enhancing cognitive development and behaviour, but that the centre-based programme showed larger effects in (i) enhancing language skills; and (ii) gross motor skills, compared to the home-based and primary care conditions. The larger language effects from the centre-based intervention suggested that longer exposure to language input in the centre-based intervention was beneficial; the gross motor effects were explained as reflecting the opportunities for outdoor and indoor play activities within the centre-based intervention on a daily basis – something which was not guaranteed under the other conditions. The authors made a strong case about the effectiveness of early intervention programmes for children at risk from prenatal exposure to cocaine, especially for enhancing language development. They further argued that these children were not inherently different from other at-risk children and suggested that results of this study might be applicable under other risk conditions as well.
Three subsequent recent evaluations of interventions within the LRIP framework (Bono et al., 2005; Bono & Sheinberg, 2009; Bolzani Dinehart, Yale Kaiser & Hughes, 2009) used additional cohorts to those in the first study (Claussen et al., 2004) and have expanded on Claussen's original findings to provide further evidence of the overall effectiveness of the LRIP, and of the impact of specific components within it.
For example, measures of language and cognition taken at 12 months across the three intervention conditions (centre-based, home-based, primary care) by Bono et al. (2005) when the children had not been in the intervention for very long (cohort mean age at enrolment 9.5 months), established no statistical differences across the groups. This meant that the improved measures on cognition and language at age 36 months reported by Bono et al. could be more confidently attributed to the intervention. As in the earlier study (Claussen et al., 2004), both centre-based and home-based intervention improved the children's language and cognition scores at 36 months relative to the children who had only primary care (health and social work) services, and language skills were more improved by the centre-based interventions versus the home-based one. The latter led the researchers to conclude that while the different levels of intensity of intervention in the centre-based and home-based intervention seemed to work equally well for cognitive improvements, language skills appeared to require more intensive interventions. They also commented that despite the improvements at age 36 months, language scores across the intervention groups remained "lower than language scores for the sample of typically developing children" (p. 280).
Bolzani Dinehart et al.'s (2009) study reports the results of implementing Milieu Teaching (MT) as an additional language intervention with four children (18–20 months old) within the centre-based intervention group of the LRIP to test if this would improve language skills above those obtained to date. Over a 16-week period each child received three individual intervention sessions a week for the first four weeks, and four sessions a week from weeks 5–16. The results demonstrated "impressive gains" (p.15) and were seen by the researchers to support the effectiveness of MT in improving language development for children exposed to cocaine prenatally. However, they also pointed out that it was very costly of time. Additionally, they highlighted that (i) the interventionists who worked with the four children "were all educated individuals with a background in child development"; that (ii) the children were also receiving the LRIP intense intervention to improve overall developmental outcomes; and (iii) the children had been selected on the basis of their age and language deficits. They cautioned that the intervention effects could differ "depending on the qualifications of the interventionists, the environmental circumstances of the child, and the child's initial abilities" (p.17).
A further recent study from the LRIP project (Bono & Sheinberg, 2009) investigated the moderating role of LBW in the relationship between early intervention for children exposed to cocaine prenatally and developmental outcomes. For this study, the children in centre-based and home-based interventions were grouped together as one intervention condition and then compared to children in the primary care group. The analysis showed that the intervention condition benefited the cognitive and language abilities of all the infants regardless of their birth weight, but it was most helpful for those with LBW. Additionally, children of LBW who were in the intervention group exhibited fewer behavioural problems and higher levels of prosocial behaviours compared to children of low birth weight who were not in the intervention group; children of normal birth weight did show behaviour problems and prosocial behaviours irrespective of whether they were or were not in the intervention group. The authors concluded that their results supported the notion of the "cumulative effect of risk" (p. 498) and strengthened the argument that children with multiple risk factors should be especially targeted for participating in early interventions.
6.2.3 Early intervention in multiple risk-factor contexts: early childhood education and care as a protective factor for academic outcomes in children
Burchinal et al. (2006) argued that given that social risk factors during early childhood are often associated with academic difficulties, it is important to identify whether high quality early childhood education can be a protective factor. Their study assessed six risk factors (i.e., poverty, father absent in household, large household size, low maternal education, high maternal depression, and high life stress) which were then collated in one multiple risk index (averaged over several data collection points during early childhood).
Burchinal et al.'s study (2006) used a sample of 75 children from low-income African American families, who were all enrolled in childcare centres full time or in Head Start programmes prior to entry to kindergarten. Infants were included in the study if they had attended community-based childcare centres and were initially enrolled aged in their first year of life (between 1 to 11 months; mean 5.4 months). Later outcomes on child development were assessed at four different time points (i.e., at entry to kindergarten, and at each of grade 1 to 3 in elementary school).
The results suggested that childcare quality (measured by the ITERS and ECERS) emerged as a protective factor over time in the area of mathematics skills, though not for reading scores or social skills. For children who attended higher quality childcare, exposure to risk was negatively related to mathematics skills in first grade much more strongly than in third grade, showing that the effect of risk decreased with time for these children. In contrast, risk became a stronger negative predictor over time for children who attended lower quality childcare centres.
The effect of risk on behaviour problems also decreased from kindergarten to third grade, whereas the effect of risk among children who attended lower quality childcare programmes increased from kindergarten to third grade.
In sum, these findings provide evidence that quality childcare might be an important protective means to reduce behaviour problems and increase academic skills among a group of children who are at risk from multiple factors.
Similar findings about the protective or buffering effect of higher quality centre-based childcare provision for under-two-year-olds were reported by McCartney, Dearing, Taylor, and Bub (2007). Using data from the longitudinal NICHD Study of Early Child Care and Youth Development, McCartney et al. (2007) investigated direct and indirect pathways between childcare quality and child outcomes, and between improvements in the home environment and child outcomes. The authors hypothesised that higher quality childcare buffers children from the negative effects of low income when it provides learning supports and when it leads to improvements in the home environment.
The study sampled infants from low income families who were in non-parental care during the first 36 months for at least 10 hours per week (M = 34.01). Childcare quality was assessed by the Observational Record of the Caregiving Environment (ORCE) with scores at four time points (6, 15, 24, and 36 months), averaged across. The qualitative ratings consisted of sensitivity to child's non-distress expressions, positive regard, stimulation of cognitive development, detachment, and flat affect; at 36 months fostering exploration and intrusiveness were also added. Based on a composite variable of total observed childcare quality, children in childcare were divided in half (below and above the mean). Thus, there were three groups of children: those in higher quality childcare, those in lower quality childcare, and those not in childcare. The children's performance on a measure of school readiness (i.e., Bracken Basic Concept Scale; Bracken, 1984), and on language competence (i.e., Receptive Language and Expressive Language from Reynell Developmental Language Scale; Reynell, 1990) were assessed at 36 months.
The results indicated both a direct and indirect relationship between higher quality childcare and children's outcomes for cognitive and language development, with higher quality childcare acting as a buffer for children from the negative impact of lower family economic resources. After controlling for nine child and family covariates, an interaction between family income-to-needs ratio (family income divided by the state poverty threshold for the appropriate family size) and childcare quality was found to predict school readiness, receptive language, and expressive language, as well as improvements in the home environment. Children from low-income families benefited from observed learning supports such as sensitive care and stimulation of cognitive development, and their parents profited from unobserved informal and formal parent supports.
McCartney et al. (2007) reported that children from low-income families in higher quality childcare performed better than children in lower quality childcare, and better than children who did not use childcare. Children in higher quality care scored highest on the test of School Readiness compared with children in either lower quality care or no care. Similar results were obtained for Receptive Language and Expressive Language; children in higher quality care scored highest on these two language subtests compared with children in the remaining groups. Even lower quality care showed some positive effects, relative to no care, for children at the poverty level. The authors concluded that childcare experience of any quality affords advantages to children living in poverty with respect to language comprehension and expression. Effect sizes increased as childcare quality increased.
McCartney et al. (2007) emphasised that children in higher quality childcare experienced teachers who were both sensitive and stimulating of children's cognitive development. Children were assumed to receive more verbal interaction in higher quality as well as lower quality childcare than they would have at home. The authors stressed that because vocabulary is one of the best predictors of literacy, the results for receptive language were the most important. Therefore, according to the authors, practitioners in early childhood settings should be trained to support language skills by offering language-rich activities, including reading, circle-time discussions, and one-on-one conversations.
Exploring further the buffering effects of higher quality early childcare, and again using data from the NICHD study, Dearing, McCartney and Taylor (2009) investigated whether the relationship between family economic status and children's achievement in maths and reading during the middle childhood was moderated by higher quality childcare in the first years of life.
As in all the NICHD analyses, the quality of the childcare centres attended by the study children was measured using the ORCE with high quality within non-maternal childcare described as ten or more hours per week in a childcare centre from the age of 6 to 54 months in which the children experienced:
- high levels of language stimulation
- access to developmentally appropriate learning materials
- a positive emotional climate with sensitive and responsive caregivers, and
- opportunities for children to explore their environments.
Dearing et al. (2009) emphasised that higher quality care for low-income families can offer material (e.g., access to learning materials) as well as psychosocial (e.g., stimulating and responsive caregivers) benefits. They further noted that providing social support to the parents is another aspect of how high quality care can benefit low-income families indirectly.
The results of Dearing et al.'s (2009) study showed that for children from low-income families higher quality childcare was associated with early school readiness, and reading and mathematics achievement through middle childhood. The authors commented:
We found that higher quality care during early childhood appeared to protect children in low-income families, promoting their reading and mathematics achievement through middle childhood. The more episodes that children spent in higher quality care between 6 and 54 months of age, the weaker the association between family income-to-needs and middle-childhood achievement. In some cases, in fact, the achievement of low-income children who experienced three or more episodes of higher quality child care was nearly as high as, and was statistically indistinguishable from, the achievement of affluent children. (p. 1344)
The authors concluded that future discussions on anti-poverty policy should place more importance on the role that higher quality early childhood education can have in ameliorating the effects of poverty.
6.3 Concluding summary
A key aim of this chapter has been to highlight the general findings from studies of the effects of high quality centre-based early childhood education for at-risk children and to identify the elements within different programmes that worked well.
Within the studies reviewed, the following characteristics are also worth highlighting as impacting on the effectiveness of early intervention programmes.
- Central-government-supported programmes, like Early Head Start (EHS) and Sure Start (SS), have the capacity to make the biggest difference most quickly. This was evident in the increased access to high quality childcare for infants and toddlers identified by the first evaluations of EHS (Love et al., 2004), and in the rapid expansion of SS (Gray & Francis, 2007).
- The different implementation protocols of the EHS and SS, and the developmental trajectory of SS, suggest there are lessons to be learned about the benefits of clear programme protocols, as well as models of community partnerships.
- Structural features of high quality identified within the studies reviewed in this chapter mirror those identified in earlier chapters. Specifically, low adult:child ratios, staff qualifications and a well-articulated curriculum are related to sustained interactions between adults and children and positive outcome measures for children (Love et al., 2005).
- Interventions with children prenatally exposed to cocaine showed that qualified interventionists were essential to the success of the intervention programme, and that additional language intervention (e.g., Milieu teaching) while expensive, was also very effective (Bolzani Dinehart et al., 2009).
- Centre-based programmes, and programmes that combine centre-based intervention with home-visiting work are better than home-visiting alone.
- There is a range of interrelated factors that impact on the effectiveness of an intervention, including ensuring access through the provision of transport for children and parents to a centre-based facility.
- Most of the interventions were multi-service provisions that met health as well as educational needs.
- Meaningful evaluation approaches need to be planned alongside the intervention (Love et al., 2005; Melhuish et al., 2008a).
This list is supported also by Herrod (2007) who summarised the characteristics of successful early intervention programmes he reviewed as:
- being relatively intensive
- at least one year long if not longer
- employing teachers who have higher qualifications than those in regular programmes
- providing better pay for teachers
- having lower student-to-teacher ratios than the norm and a limited total classroom size
- being generally research based and designed to have a control group and specific outcome measures
- having greatest impact where there is greatest risk.
With regards to the effects of early intervention studies on children, studies reviewed in this chapter have shown that:
- high quality early childcare in the first years of life had beneficial effects that persisted into adulthood (e.g., Campbell et al., 2008; McCormick et al., 2006)
- effects from high quality early childhood programmes were discernible in adult cognitive and academic achievements, including reading and mathematical skills, and in vocational outcomes in adulthood (Campbell et al., 2008)
- benefits to children include better social development, positive social behaviour, and greater independence (Melhuish et al., 2008)
- some of the gains from quality childcare in the first years of life may not be seen until late adolescence and early adulthood
- children benefit from less negative parenting (Melhuish et al., 2008)
- low-birth-weight infants can benefit from early intervention in both cognitive and behavioural domains (McCormick et al., 2006) and high participation rates in early intervention may be more effective for lighter low-birth-weight infants (Hill et al., 2007)
- both centre-based and home-based intervention had beneficial effects on children prenatally exposed to cocaine who were enrolled in the Linda Ray Interventon Project with the best outcomes for language skills and gross moter skills experienced by children enrolled in the centre-based intervention
- with children who are multiply at risk, higher quality early childhood education acts as a buffer from the effects of the risk factors in relation to academic achievement at school and in relation to behaviour problems (Burchinal et al., 2006; Dearing et al., 2009; McCartney et al., 2007)
- for children in poverty, high quality childcare had the best buffering effects, and for these children the buffering effect also applied in childcare of lower quality.
With regards to the effects of early intervention studies on parents and families, this review found that:
- parents benefit from the support for their children's learning and language which make the parents more responsive to the child's bids for attention at home
- parents benefit from programmes that provide targetted access but challenges can remain in some neighbourhoods due, for example, to transportation issues, or lack of information (Love et al., 2004)
- parents in EHS read more to their infants than parents in the control group (Love et al., 2005) and provided a more stimulating home-learning environment (Melhuish et al., 2008a)
- early intervention programmes can provide practical support as well as emotional support, such as by 'minimising the chaos' while the youngest child is at the centre (Dearing et al., 2009; Melhuish et al., 2008a).
Overall, the combination of these findings lends credence to the conclusion reached separately in a number of the studies reviewed, namely that high quality early childhood education can make a lasting difference and act as a protective factor for children at risk. It therefore makes sense for future policy to take account of this role of high quality early childhood education in planning strategies to enhance children's life chances.
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- Studies related to other well-known longitudinal studies, such as the High/Scope Perry Preschool Project, and the Chicago longitudinal study in the US, and the Effective provision of Pre-school Education (EPPE) in the UK were excluded from our review as children were enrolled in these programmes from the age of 3 years, beyond our target group of 0–2 years old.
- A helpful visual representation of the design of the Abecedarian study is presented in Ramey et al. (2000).
- Exact ratio not stated in Campbell & Pungello (2000).
- having incomes at or below federal poverty level
- Regulations for the provision of early childhood services vary from state to state in the US
- Jay Belsky is currently based at Birkbeck College at the University of London, and continues to also be involved in ongoing analysis of the NICHD study of early child care and youth development.
- Child positive social behaviour: child is generally obedient, can stop and think before acting, sees tasks through to the end, has a good attention span, thinks about other people's feelings, shares readily with other children, is helpful if someone is hurt, upset, or feeling ill, is kind to younger children, often offers to help others.
- Independence: child likes to work things out by himself or herself, does not need much help with tasks, chooses activities independently, persists with difficult tasks, and can move to a new activity after finishing a task.
- A risk is identified and a strategy developed to target its prevention.