The First Twelve Months: a Literature Review

INTRODUCTION

We have known for some time now that children's early years have a major impact on their later development and life chances. This paper outlines evidence suggesting that the very earliest period of a child's life - pregnancy and the first twelve months of life - may be particularly important. It highlights research on a range of issues including the impact of early childhood poverty and deprivation on later outcomes, the relevance of key child health indicators such as low birth weight, new evidence about the importance of early brain development and the impact of parenting. The paper also includes evidence on the effectiveness of different policy interventions. It concludes by suggesting the key issues raised by the research which merit further exploration during the course of The First Twelve Months project.

POVERTY, DISADVANTAGE AND LATER OUTCOMES

There is substantial evidence that the burden of poverty in this country falls disproportionately on children. In the mid 1990s, one in four of the total population was living in poverty. For children, the proportion was one in three (Oppenheim and Harker, 1996). Research suggests that that having a child is the cause of poverty for one in three poor families and that having a child and additional children has a much greater impact on the standard of living of poorer families than better off households (Berthoud and Ford, 1996). Child poverty has grown rapidly over the past three decades, particularly from the late 1970s onwards. Child poverty[1] tripled between the late 1960s and mid 1990s, from one in ten to one in three with the increase (Gregg et al, 1999). Levels of support for poor children, particularly very young children, have been shown to be insufficient. For example, studies of the costs of meeting the basic needs of children of different ages not only suggest that the income provided by Income Support is insufficient, but that the personal allowances for children underestimate the costs of younger children (especially those under two years) relative to older children (Hills, 1998).

It has been argued that poverty during the early years of a child's life is particularly harmful as it is more powerfully predictive of later achievement than poverty at any subsequent stage of their development (Shonkoff and Phillips, 2000). The impact of being brought up in poverty on later outcomes has been demonstrated in the UK and other countries. Data from the National Longitudinal Survey of Children and Youth and the National Population Health Survey in Canada, for example, has shown a clear link between family income and twenty seven different factors that are critical to child well-being, including learning capacity, behaviour and health status. In 80 per cent of these factors, child outcomes improve substantially as annual family income rises (Ross and Roberts, 1999). Evidence from the National Child Development Study (NCDS) in this country has found large differences in cognitive functioning by income. Research by McCulloch and Joshi (1999) suggests that the sustained experience of poverty[2] may be particularly damaging for cognitive ability. Small changes in families' economic circumstance may be insufficient to tackle the problem: "large changes in child development would need large economic changes, and probably long term economic development".

The adverse consequences of being brought up in economically disadvantaged families persist into adulthood. Data from the NCDS and the Family Expenditure Survey has shown a marked relationship between childhood disadvantage at age 7 and economic and social outcomes in adult life. People who grow up in families facing financial difficulties have higher rates of joblessness, lower employment chances and a higher probability of having a spell in prison on borstal at age 23. Disadvantages persists at age 33, with men experiencing worse economic outcomes (lower wages and employment) even after controlling for education differences (Gregg et al, 1999). Other studies have shown that class of origin is linked to adult outcomes, exercising an impact largely through achievement at school and higher education but also maintaining an independent effect on adult occupational attainment (Brynner et al, 2000).

The effects of childhood disadvantage can last not just across an individual's lifecourse but also across the generations. Children who have at least one parent who faced social disadvantage in their own childhood achieve a lower percentile ranking on maths and reading tests at age seven (Gregg et al 1999). Children whose fathers and mothers have not stayed on at school (which is in itself strongly related to family class at birth) are more likely to leave school at age 16 than those with more educated parents (Brynner et al, 2000).

However, the causal mechanisms linking deprivation and later outcomes are highly complex and yet to be understood fully. Low income in itself may not be an adequate proxy for deprivation. McCulloch and Joshi (1999) suggest that factors that are probably involved in a direct effect include poor housing conditions and a lack of cognitively stimulating resources like books in the home. Low income families may suffer disadvantages from living in disadvantaged localities with poor local services and low social capital. Living in a family which lacks financial or social resources might also affect parents self-esteem which is likely to have a negative effect on parenting and mental or emotional well being.

Maternal education may be a particularly important aspect in relation to early childhood development because it can be a key determinant of mothers verbal interaction with their children (Shonkoff and Phillips, 2000). (This issue is returned to below.) Maternal education has been shown to have an effect on child test scores, even after controlling for income (McCulloch and Joshi 1999). However, the evidence on the impact of providing extra maternal education in improving children's outcomes has so far been mixed. One US study found that maternal education had no impact on young children's achievement scores, but another found that an additional year of maternal schooling during the child's first three years had a significant and large positive effect on children's receptive vocabulary (Rosenzwig and Wolpin, 1994).

It is important to emphasise that the associations between poverty, disadvantage and later outcomes are aggregate tendencies and are in no sense determinist (Hobcraft, 1998). In other words, risk is not destiny. Many children who grow up in poverty become economically and socially productive adults. Low socio-economic status reduces the chances of success rather than leading inevitably to diminished attainment.

Indeed, there is increasing evidence about the 'resilience' factors which seem to protect children growing up in low income families. For example, a longitudinal study in Australia found that a third of children who experienced chronic adversity from a young age went on to succeed at school, find meaningful employment and establish positive relationships with their immediate family, peers, teachers and neighbours. The children who were resilient in the face of disadvantage were found to have strong attachments to their primary care giver (not necessarily their mother), an 'easy' temperament and above average intelligence. They also received a considerable amount of positive attention and had three or fewer siblings, with children spaced by at least two years (Werner, 1997).

Researchers in this country have also stressed the importance of protective or resilience factors including the presence of dependable caregivers, self-confidence and self-esteem, the capacity to create and maintain friendships with peers and to gain the support of adults, trust in and empathy with others, an internal locus of control with a sense that the child can influence their circumstances,optimism and clear aspirations, and reflectiveness and problem solving capacity.[3] The effects of these factors point to the critical role parents can play in ameliorating the disadvantaging effects of poverty. (The importance and consequences of parenting are discussed in further detail below.)

MATERNAL EMPLOYMENT AND CHILDCARE

There has been a substantial increase in the economic participation rates of women with pre-school children in recent years, from 45 per cent in 1988 to 55 per cent in 1998 (Thair and Risdon, 1999)[4]. The impact of maternal employment on child outcomes, particularly during the earliest years of life, has been the subject of much debate in recent years.

The evidence on this issue is mixed. In the US, researchers have tended to find adverse associations between employment begun in the first year of a child's life, in terms of both cognitive development and behavioural adjustment. In this country, Joshi and Verropoulou (2000) recently examined the impact of maternal employment whilst children are under one on maths and reading scores at age 10 and emotional adjustment scores at age 8 and later, using data from two National Birth Cohort Studies. They found that early maternal employment tends to go with poorer outcomes but that this is only statistically important for reading scores. Small positive associations with later outcomes were shown with mother's employment once their child is over one year old. The study concluded that poor economic circumstances in the home and the mother's own academic ability and attainments are in fact more important predictors of child academic and aggression scores than the mother's employment during the first year of life (Joshi and Verropoulou 2000).

Other research suggests the circumstances of the work mothers undertake matters more than mothers working per se. Non-standard working hours, especially long hours during the first year of life, may pose a risk for child development, especially when combined with poor quality childcare: "Parental employment can bode well or ill for young children depending on the features of the work, the income it generates, the nature and structure of the job, its timing and total hours and ... the environment and relationships that children experience when they are not in the care of their parents" (Shonkoff and Phillips, 2000). How mothers feel about working during the first year of their child's life also appears to be critical to children's outcomes. In the US, Hoffman et al (1999) found that the positive effects of work on a mother's sense of well being may be crucial in providing later advantages for children. In this country, Kiernan (1996) has shown a positive association between lone mothers employment and children's qualifications, suggesting this may be due to the effects of positive role models.

A critical issue raised by Joshi and Verropoulou's research (1999) is the quality of childcare that children receive whilst their mothers are working, and that young babies may be particularly vulnerable to poor quality care. The effect of childcare on children's cognitive ability and behaviour in later life have been the focus of considerable research. Some evidence suggests that childcare begun in the first year of life has a different effect on later emotional adjustment and cognitive development than care begun thereafter. Baydar and Brooks-Gunn (1991), for example, found that childcare during the first year of life has a negative effect for some groups, whilst care for children aged over one year has a positive effect (Baydar and Brooks-Gunn, 1991). However, very few studies have controlled for the quality of childcare being provided. Those that do have found it plays a vital role (NICHD, 1997).

The quality of childcare seems to be particularly important in relation to children from low income families. A comprehensive review of studies of pre-school and childcare programmes across the developed world in the mid 1990s[5] found that the quality of childcare exerted more influence on the development of children from low income families compared to other children. For disadvantaged children, there was a greater positive impact as a result of high quality care and a greater negative impact from poor quality care (Boocock, 1995). Other research supports this finding. For example, low income children's cognitive development has been found to benefit more from high quality child care compared to children from other families (Caughy et al, 1994).

Most of the evidence about the impact of the quality of childcare on later outcomes comes from the US. Although we can learn a great deal from carefully conducted research in other countries, it is important to compare like with like. We actually know very little about the type or quality of childcare being provided to children aged under one in the UK. Some evidence of the type of childcare used by mothers with children under one is provided by a recent study of 412 first time mothers conducted by the Work-Life Research Group at the University of Kent. The study found that 78 per cent of working mothers whose children were one year old used some form of commercial childcare[6]. 28 per cent of non working mothers in the sample also used commercial childcare for leisure or personal activities (Houston et al, 2000). However, longitudinal research will be crucial if we are to understand fully the effects both of different types of childcare and the quality of childcare being provided on later outcomes in this country (Waldfogel, 1999)

NEIGHBOURHOOD AND COMMUNITY INFLUENCES

This paper has so far explored the evidence about children who are brought up in disadvantaged families and the impact this can have on later outcomes. However, families do not exist in isolation: they function within the context of their local neighbourhoods and wider communities. There has been growing interest in the links between neighbourhood and community factors and child outcomes in recent years, particularly in the US. This is a difficult and complex field of research. It is extremely hard to isolate the specific effects of different neighbourhood or wider community influences. Most existing data sets do not include measures of the family, neighbourhood or community processes that are likely to have an effect. In those that do, the tendency of these different measures to be highly correlated and our lack of knowledge about the relationships and interplay between them makes it difficult to assess their relative importance or to clarify their direct and indirect effects (Brooks-Gunn et al, 1997).

To date, much of the research in this area has focused on outcomes for older children as most children have somewhat limited contact with the environment outside their home during the earliest months of life, except for involvement with extended family, visits to healthcare providers and/or day care. However, one study using data from the US National Longitudinal Survey of Youth (NLSY) and the Infant Health and Development Project (IHDP) recently assessed the impact of five neighbourhood characteristics - low socio-economic status, high socio-economic status, male joblessness, family concentrations and ethnic diversity - on cognitive and behavioural outcomes for children at age three.

The study's main finding was that very few neighbourhood characteristics had an impact. For both cognitive and behavioural outcomes, family factors (specifically family income and mothers’ education) accounted for most of the variance identified. The authors conclude that "the family is the primary socialising unit for pre-school children and that direct neighbourhood influences on such young children are small, or filtered by family experience" (Chase Lansdale et al, 1997). However, a strong and significant link was found between the presence of affluent neighbours and children's IQ scores. The study points to the absence of relatively affluent families being the important variable, not the presence of low income families. In terms of behavioural functioning, male joblessness was found to be a significant factor although only in the NLSY data. The reason why these neighbourhood factors had an effect on outcomes is unclear. The study's authors suggest that the presence of affluent families could lead to better local services and community resources being provided, whilst the impact of male joblessness could be related to the type of role models available for children, although this explanation would clearly make more sense in terms of adolescents than pre-schoolers (Chase Lansdale et al, 1997).

INFANT MORTALITY

There were 5.7 deaths per thousand live births in England in 1999. This rate is expected to fall below 5 deaths per thousand live births by 2006. Infant mortality rates are higher amongst babies born to parents in lower social classes. For children under one, infant mortality rates are around seven per thousand live births for children born to parents in social classes IV and V compared to five per thousand live births for children born to parents in social classes I and II. As with mortality rates at other ages, infant mortality rates in each class are decreasing. However, there is no evidence that class differentials in infant mortality have decreased over recent years (Independent Inquiry into Inequalities in Health, 1998): indeed, analysis of recent trends suggests a widening gap between the infant mortality rates of children of manual social classes and the population as a whole.[7]