Systematic review of parenting interventions in European countries aiming to reduce social inequalities in children’s health and development

During child growth, neuron connections produce cognitive, motor, emotional, behavioural and social developmental skills [1]. Childhood risks associated with poverty or similar adverse conditions, such as lack of stimulation or excessive stress, affect brain development. The risks begin prenatally by influencing the foetal brain through exogenous factors that produce maternal stress [2]. Early child development [ECD] will influence many aspects of wellbeing, health, competence in literacy and numeracy, criminality and social and economic participation throughout the life course [3–5].

The early acquisition of skills is part of a developmental continuum and commences well before formal schooling [6]. By the time the child enters school, development will have already been influenced by family, neighbourhood and the broader societal level [7]. Family socioeconomic status [SES] is associated with a multitude of development outcomes [8], for example, it has been described that children of mothers with mental health problems were more likely to have negative behavioural, emotional, and peer outcomes [9]. Low family SES also produces obesity in childhood and adolescence and may exert a strong influence on socioeconomic status [10]. Children from disadvantaged groups are less likely to achieve a good level of development and have worse health outcomes [11]. Neighbourhood deprivation and the physical context also influence early child development [12, 13] and children from family backgrounds that pose multiple threats to their development tend to do better growing up in mixed socioeconomic neighbourhoods [14].

These different qualities of experience create social gradients in human developmental trajectories across the life course [15–17]. As described elsewhere, children from the 1970 British birth cohort survey assessed by tests of intellectual, emotional and personal development who were in the bottom SES quartile at 22 months were still there at age 10. High-SES children showed considerably more upward mobility and were more likely to be in the top quartile by age 10, even if they were in the bottom quartile at 22 months [18].

Evidence from intervention studies suggest that performance in the different domains of Early Child Development [ECD]-described as the development of physical, socio-emotional and language-cognitive capacities in the early years-[19] can be modified in ways which improve health, well-being, and competence in the long-term [8]. By providing a positive start across the social gradient, children will benefit from improved developmental outcomes during later childhood and throughout their life course as significant improvements in all domains of child development will influence later school achievement [20]. The overarching conceptual framework for this study: “Action across the life course”-as described in the Strategic Review of Health Inequalities in England post-2010-[21] shows that disadvantage starts before birth and accumulates throughout life. Therefore, action to reduce health inequalities must start during gestation and be carried out through the life of the child and into adulthood. This may be made effective by providing evidence-based interventions and delivery systems [20, 21].

Studies which have shown the importance of parenting activities across income groups and the social gradient [15] fostered through ECD programmes are not limited to cognitive gains, but also include physical, social, and emotional gains, all of which are determinants of health over the life course [3]. The quality of parent–child relationships is significantly associated with many outcomes relating to child health and development, including learning and social skills, mental health and health behaviours and remain influential into adulthood for social and behavioural outcomes. Parenting programmes offer valuable opportunities to positively influence child health and well-being through health-promoting environments, establishing good health behaviours, providing support for families and creating resilience [22]. Examples of early years programmes delivered in the USA have been well documented: “The Perry Preschool Project” delivered during 1962–1967 and the “High/Scope Preschool Curriculum Study” (1967–1970) which showed positive outcomes for test scores, high school completion, lower arrests and criminality, teenage pregnancies and higher home ownerships. The “Carolina Abecedarian Project” (1972–1985) and the “Syracuse Family Development Research Program” (1969–1975) had an impact on improving development and IQ scores [19, 23].

The economic return to these programs is high, especially when considering alternative policies that target children from disadvantaged environments or the policies targeting the young adults who emerge from them [24]. There is sufficient scientific rationale for early intervention [25], as social inequalities develop before birth it is more effective to deliver interventions not only in the early stages of the child’s life [26], but also before birth and has been established as a priority at the UN Convention on the Rights of the Child [7].

It has been argued as a principal recommendation in a previous study, that future reviews should focus on identifying interventions [17] and to our knowledge, there are few scientific reviews of interventions to tackle health and developmental inequalities in early child development focusing only on European studies. The majority include intervention studies carried out in the US, Canada and Australia or in low income and high burden countries [27, 28]. The WHO European Region includes countries with close to the best health and narrowest health gaps in comparison to other continents and has benefited from a sustained period of social cohesion, developed welfare states and high-quality education and health services [29]. However, inequalities still remain and are increasing in some countries, therefore the different set of conditions across Europe offers the possibility of evaluating evidence on the effectiveness of early interventions on families’ socio-economic conditions as well as the physical functioning and development of children in the early stages of their lives.

By reviewing this evidence, the objective of this systematic review was to identify relevant existing literature on interventions carried out during early childhood in countries within the Region during the years 1999–2013 which address children’s health and development. The review forms part of the DRIVERS Project (2012–2014) – a three-year research project funded by the European Union 7th Framework Programme focusing on three of the key drivers to reduce health inequities: early childhood development, employment and working conditions and welfare, income and social protection. It assesses the impact of policies and programmes to develop new methods and evidence and provide policy recommendations and advocacy guidance to reduce health inequalities within Europe. The research builds on the recommendations of the Commission on Social Determinants of Health (CSDH) [11], The Strategic Review of Health Inequalities in England post-2010 [21] and The Review of Social Determinants and the Health Divide in the World Health Organisation European Region [29] and seeks to contribute to the EU 2020 initiatives [30].

This review identified eleven intervention studies published in peer reviewed journals in Pubmed and IBSS databases and twelve identified in NICE's database. It showed that all but two interventions targeted children and families living in deprived areas. These were aimed at providing parents with emotional support and parenting skills or resources and materials enabling them as active agents in the interventions. They were delivered in families’ homes by specialised home visitors or multidisciplinary staff and in clinics by health care professionals or in community centres and churches through workshops and individual sessions. All selected interventions had undergone an evaluation.

The interventions with better outcomes combined various activities such as workshops and educational programmes for both parents and children beginning during early pregnancy and included home visits by specialised staff. These provided parents with training and material resources to enable them as active agents in intervention delivery; for example, PFL [22] or “Let’s Play in Tandem” [46] showed more positive results than “The Social Support and Family Health Study” [36] or the intervention aimed at children with failure to thrive which were based almost exclusively on home visits. However, “Sure Start” [19] and “Eager and Able to Learn” [22] with similar programmes and structures had mixed outcomes. It has been described in previous evaluation reports that “Sure Start” research teams faced methodological challenges and the number of Sure Start Local Programmes (SSLPs) increased substantially, reducing the opportunity to identify suitable comparison areas [47]. Programmes with better outcomes also included elements such as interagency participation. An example of these is “Incredible Years” a preventive intervention successful in reducing behavioural problems and negative parenting in highly disadvantaged community based settings delivered by regular Sure Start staff. Furthermore, interventions delivered by specialised professional home visitors, such as the CDI [22] had more impact on positive parenting and reducing negative and submissive conducts in children than programmes delivered by volunteers or other non-professional home visitors like the “Community Mothers Program” [19]. They also had better outcomes than programmes such as “The Speech and Language Therapy” (SLT) and “Ready Steady Grow” (RSG) [22], delivered after birth during shorter periods. RSG, aimed at children 3–18 months showed more favourable outcomes for speech and language development than SLT, delivered to children 2–6 years old. Other interventions with favourable outcomes in improving child behaviour and reducing abuse and neglect such as “Triple P” [19], for example, were tailored to meet the child and family’s needs and offered different levels and intensity of activities and support.

Targeted work with parents through provision and fitting of safety equipment providing information such as the “First Parent Health Visitor Scheme” [19], showed reduced accident rates and increased precautions, however these interventions were targeted at very specific outcomes and used less rigorous methods and comparison groups than the abovementioned interventions with wider scopes and sample sizes. The “Developing Everyone’s Learning and Thinking Abilities [DELTA] parenting programme” [43], “Limerick Lullaby Project” [44] and “Baby Fast” [45] focused on mother and child bonding had positive outcomes and were evaluated using qualitative research methods. Some RCTs and quasi-experiments with a control group had more primary and secondary outcomes with no significant differences but had larger sample sizes and in particular the first may have a stronger level of evidence [48]. As it has been described elsewhere, small imbalanced sample sizes may reduce the power to detect differences and makes the study vulnerable to chance variation [49].

Some of the interventions identified are also implemented in countries such as Australia, Canada and the United States of America (USA). The Family–Nurse Partnership has shown long-term beneficial effects in the USA. It was evaluated by three RCTs and showed higher reading and mathematics tests scores in IG children. Long term evaluations showed children had fewer sexual partners, less smoking and drinking or ingestion of dangerous substances. Injuries and abuse were also reduced as was criminality during later years. In the UK, the FNP, has recently undergone a formative evaluation: nurses’ and mother’s feedback was very positive and provided support for the argument that group FNP-delivered to mothers who were not eligible for FNP-has been received well over the whole time period of the programme and good links were being made with other services [50]. However, if further evaluations are carried out, the results may not be as positive as those in the USA because the health visitor system and a universally accessible primary care system are already in place in the UK [19]. The evaluation of “Sure Start” Australia discovered that that there were very little detectable difference between the Sure Start Local Programmes and Start-to-be communities on most of the dimensions measured by the evaluation [51], similarly to “Sure Start” in the UK.

“Incredible Years” UK which showed favourable outcomes for socio-emotional development and behaviour replicated the results [52] found by Webster-Stratton’s evaluation of “Head Start” in the USA: intervention children were observed to exhibit significantly fewer conduct problems, less noncompliance and more positive affect than control children. One year later, most of the improvements were maintained [53]. Therefore, interventions with similar components were able to obtain the same results in a different context. The long-term outcomes of these programmes are important as children who show early persistent signs of antisocial behaviour are at greater risk of later juvenile delinquency and social exclusion with higher societal costs [52].

The majority of interventions identified were targeted at children living in deprived areas; the interventions were aimed at reducing social inequalities in children’s health and development by improving outcomes across the different domains among the most deprived populations. Previous studies suggest that the living conditions for young families should allow mothers to start pregnancy in a health-promoting environment as inequalities in health and development become set relatively early in life. Parents, teachers, health policies and services provide key guidance leading to the development of healthy outcomes [54]. To achieve equity from the start, it is important to foster the acquisition of cognitive and non-cognitive skills, which are strongly associated with educational achievement and with a whole range of other outcomes including better employment, income and physical and mental health [21]. Delivering programmes and interventions in disadvantaged areas will possibly help reduce health inequalities in later life, adulthood and throughout the lifecourse. These may also help reduce the intergenerational transmission of health inequalities as social and economic inequities affecting previous generations present an important influence on children’s life-course, and affects their life chances and health. Growing up in relative poverty has a strong influence on health and other outcomes throughout life [29]. However it has also been argued that while targeted pre-school education programmes have been found to have long-lasting effects on the social trajectories of poor children, improving their educational levels and employment prospects, their life chances remain significantly poorer than those of advantaged children not in receipt of targeted support [55].

From a critical point of view, only two interventions offered a proportionate universal approach by targeting need within universal delivery. Nearly all interventions identified were targeted, offering selective provision of services to children showing early manifestations of a problem or were at-risk of developing a problem early in life, as defined by the Organisation for Economic Co-operation and Development [56]. These were aimed at reducing inequalities in health and development among people living in deprived areas but not at levelling the social gradient in health. Within the gradient, health is progressively better the higher the socioeconomic position of people and communities. Therefore, it is important to design policies that act across the whole gradient and to address the people at the bottom of the social gradient and the people who are most at risk as described in the Review of social determinants and the health divide in the WHO European Region [29]. In similar reviews the authors found that most of the parent/infant stimulation programs dealt with “high-risk” children or interventions which focused almost exclusively on downstream initiatives in deprived areas [57]. Furthermore, the studies which were not targeted did not describe in their findings whether they had a differential impact for disadvantaged groups. However, by focusing only on high-risk families’ health outcomes, interventions are less likely to reduce inequalities across the social gradient and may not provide the best conditions for all children in which to develop and reach their full potential [21, 58]. Effective programmes should be universally available, with particular efforts made to ensure that all populations are reached, including the traditionally hard to reach [59].

In this review, interventions were based on improving parenting skills. Much of the published literature on early years interventions focuses on providing parents with support to improve their child rearing skills. These promote parenting behaviours which improve child cognitive development and help improve child attachment as positive effects of well-developed interventions, as described elsewhere, persist beyond schooling and into adulthood. While these parenting interventions are important, it is also necessary to address the conditions of daily life which make positive parenting difficult [29]. This requires policies aimed at children through an explicit, multi-dimensional and integrated strategy [26] and investment in reducing child poverty, improved living conditions and quality of housing, for example [11].

High quality child care has been described as being crucial for children’s development [29, 60] and is seen as service provision in some countries: 85% of mothers with children in preschool were in paid employment in the early 1990s in Sweden, for example. In other countries it receives limited public funding, the quality and type of services being more diverse and access to high quality child care restrictive for families with lower incomes [31]. However, only three studies assessing the impact of child care were identified in this review. Previous reviews - based on intervention descriptions - found that children’s centres were increasing in number in the UK, as part of a strategy of social investment [61, 62]. Studies by Melhuish and colleagues found that high quality children’s centres appeared to reduce socioeconomic inequalities, as children from less advantaged backgrounds benefited more than those from more advantaged backgrounds. Preschool participation was associated with strong benefits for later educational and job outcomes [63, 64]. Similarly, Feinstein [6] found that RCT studies showed a clear benefit for disadvantaged children who attended high quality pre-school childcare provision. Effective pre-school provision in England and Northern Ireland has shown evidence of longer-term benefits for all children and as described in Currie [31] this evidence has influenced policy in countries such as Australia, Norway and the Republic of Korea. Furthermore, the “Abecedarian Project” and the “Perry Preschool Project” delivered in the USA which showed very positive results as described earlier had high-quality childcare and education components and were highly resourced [59].

Interventions were heterogeneous in their study population and sample size targets, outcome measures and furthermore, there was a large divergence in the quality of their study design. Interventions with better outcomes and a higher level of evidence combined workshops and educational programmes for both parents and children beginning in early pregnancy and included home visits by specialised staff. More literature reviews focusing on the grey literature are needed to develop a larger evidence base on early childhood interventions. Further evaluation of early years interventions should be carried out especially in countries outside the UK within the European context. This review may be a useful tool to provide evidence on effective interventions for specific early childhood development and health outcomes.