Caregiver-mediated interventions for the prenatal period through infancy and early childhood are generally oriented towards
prevention. That is, rather than addressing concurrent problems with the child, they are based on the supposition that targeting known precursors of child problems is an effective way to prevent those problems. Among the most influential work in this area has been the home visitation programme developed and evaluated by Olds and colleagues to prevent antisocial behaviour in children.⁽⁴⁾ This project involved a randomized control trial that included longitudinal data collection over more than 25 years.⁽⁵⁾ A total of 400 pregnant women were enrolled in the original study according to one of the three following criteria: under 19 years of age, unmarried, or of low socioeconomic status. Those assigned to the intervention condition received an average of 9 home visits during pregnancy and an average of 23 home visits between birth and the child’s second birthday. The home visits were conducted by nurses. The focus of visits was upon prenatal and neonatal maternal health behaviours, child care skills, and maternal life issues (e.g. education and employment).

Olds and colleagues reported 15-year outcomes for the children of the mothers in this study. Those in the intervention group reported fewer arrests than those in a comparison group.⁽⁶⁾ In addition, among those in higher risk categories (as indicated by their mother being both low SES and unmarried at the time of the child’s birth), youth in the intervention group reported lower rates of running away, arrests, criminal convictions and parole violations, and smoking and alcohol consumption than did youth in the comparison group. The authors concluded that this approach may be an effective means of preventing early-onset conduct disorder, which has been considered the more treatment-resistant and complex form of the disorder.⁽¹⁾ However, it is also noteworthy that, in subsequent randomized trial studies to examine how variations in the programme structure affect outcomes, the intervention was found to be less effective when paraprofessionals were used in place of nurses as home visitors.⁽⁷⁾ More recently, and consistent with other evidence-based programmes, the emphasis of Olds and colleagues has shifted to a wide-scale dissemination of the intervention in community settings.⁽⁸⁾ Within this context, emphasis has been placed on maintaining the programme’s effectiveness by developing practices to ensure that the intervention is delivered with high fidelity to the original model.

It is important to recognize that not all caregiver-mediated preventive interventions for children in this age group have shown positive effects. For example, the Healthy Start programme was designed to prevent child abuse and neglect, using an initial screening process (usually in hospital settings) to identify families at risk for child maltreatment and employing a home-visitor model of service delivery for the intervention. Although modest positive effects were observed in individual sites implementing this programme, the overall results from a large-scale randomized trial of this intervention did not support the efficacy of the intervention.⁽⁹⁾ A related problem in the evaluation of the Healthy Start programme was low rates of family participation. Of those recruited, many received very few home visitation sessions. With such low dosage rates, it can be difficult to determine whether the lack of positive intervention effects was due to a failure of the approach to impact targeted behaviours or was due to families receiving too little of the intervention for it to have been effective. Thus, as is true across the span of child development, it is important to consider what the critical elements of effective interventions are and to make sure that these are included in any intervention efforts.

The preschool years are marked by a number of important developmental changes. Dramatic increases in the use of language and physical mobility in addition to an increase in autonomous behaviour provide challenges for many parents. Preschool children need substantial support from parents and caretakers in socialization in their family and school environments. As a result, as with interventions in infancy, the majority of caregiver-mediated interventions at this age are focused on parenting, and the parent–child relationship.

Within the parenting literature, there are many different types of parenting skills that have been found to be important in promoting healthy child development. Typically, interventions include a dual focus on increasing positive parenting and decreasing negative parenting. Positive parenting usually refers to supportive, warm, involved parenting that includes praise, positive support, approval, and responsiveness to children and their needs.⁽¹⁰⁾ Negative parenting usually refers to parenting deficits, including poor limit setting, inconsistency, verbal and physical aggression, and harsh discipline.⁽¹¹⁾

Caregiver-based interventions at this age typically focus on building a strong positive parent–child relationship in addition to teaching specific behaviour management techniques to promote healthy child adjustment and prevent later problems. Although some programmes target at-risk children, such as Head Start children or those with early behaviour problems, there is some evidence that more severe child behaviour problems are related to more limited effects of parent training programmes.⁽¹²⁾

One of the more successful caregiver-based programmes for preschoolers, The Incredible Years, was developed by Webster-Stratton and colleagues.⁽¹³⁾ This videotaped programme includes a number of salient parenting skills for preschoolers, starting with building a positive parent–child relationship, praise, and rewards and moving to limit setting, problem solving, and discipline. Randomized trial evaluations have suggested that this programme is effective when administered in group and individual settings.⁽¹⁴⁾ Results have suggested that the programme improves parent–child interactions immediately post-test and 1 year later. The programme was subsequently expanded from basic parenting skills to include more advanced parenting, such as anger management, communication, and self-control skills, which is also effective at improving the parent–child relationship and reducing child behaviour problems at short-term follow-up. The advanced programme is able to deal effectively with parent–child problems and the mediators that might influence the parent’s ability to effectively manage the child, including depression and the marital relationship. Overall, this parent training programme has been effective with a number of different age groups and populations, including preschool- and school-aged children as well as clinic-referred and community Head Start families.⁽¹⁵⁾

Other caregiver-mediated interventions involving preschoolers have also shown success at enhancing the parent–child relationship and decreasing child behaviour problems. For example, Parent– Child Interaction Training (PCIT) was originally developed for at-risk children enrolled in Head Start.⁽¹⁶⁾ Training involved teaching parents effective play skills and positive interaction. The programme has been effective at reducing teacher ratings of behaviour
problems 1 year after the intervention was completed. This approach has subsequently been used for other populations. For example, Chaffin et al. reported on the results of using PCIT to prevent child abuse among families with a history of child welfare system involvement.⁽¹⁷⁾ The intervention significantly reduced future reports of maltreatment. Interestingly, an enhanced version of the intervention designed to provide individualized services to meet families’ needs was no more effective than the original PCIT intervention.

Home visitation programmes in preschool have also shown promise as effective interventions. Head Start, for example, provides home-visiting services to all families in the programme. The goals of these visits are to work with families on meeting the Head Start performance standards in four areas: education, health– nutrition–mental health, social services, and parent involvement. Research has indicated that children who received home services have shown improvements in the parent–child relationship and early academic achievement compared to children and families who did not receive the home visits or parenting model.⁽¹⁸⁾ Home-visiting programmes at this age also provide families with social support, self-efficacy, and a positive therapeutic relationship with the visitor. This relationship serves to enable parents to process and understand parenting and family histories that impede the development of successful parenting skills with their own child.

As children move into the school years, they face a new set of challenges at home and in the school environment, including academic achievement, negotiating peer relationships, and the demands of teachers and the school context. At this age, children who have begun developing problems in the context of their families may generalize these problems to the school environment, which is associated with increased risk of later difficulties in addition to problems across multiple domains of functioning.⁽¹⁹⁾ As a result, the transition to school serves as an important target of preventive intervention programmes.⁽²⁰⁾ Furthermore, school problems and peer difficulties may exacerbate problems in the home as parents struggle with issues such as homework completion and their child’s social skills and changing peer network. Thus, effective interventions aimed at school-aged children must support families and parents through an emphasis on parent training and improving or maintaining academic achievement and positive peer relationships at school.

Although the emphasis on increasing positive parenting skills and decreasing negative parenting is typically maintained in interventions at this age and across development, additional components targeting academic achievement, learning and early literacy, and parent–school involvement are important aspects of comprehensive, caregiver-mediated interventions for school-aged children. There are multiple examples of comprehensive, caregiver-mediated prevention programmes that have been associated with positive outcomes for school-aged youth and families, including the Families and Schools Together (FAST) Track programme,⁽²¹⁾ the Linking the Interests of Families and Teachers (LIFT) programme,⁽²²⁾ and the Schools and Families Educating (SAFE) Children programme.⁽²³⁾

The FAST Track programme began in 1991 and targeted children in early elementary school at risk of developing later conduct disorder and delinquent behaviour problems.⁽²¹⁾ Children and families received a multifocused intervention package targeting development across multiple domains, including peers, the school environment, academic achievement, and the family context. The family intervention integrated successful approaches to parent training regarding the development of school-aged children, including parent–school involvement and early reading.^{(21, 24, 25)} Parents met in groups weekly during the first-grade year and bi-weekly in second grade. One hour of parent–child learning activity that emphasized positive parent–child interactions in a controlled environment and early literacy was also provided. Home visits and individualized programming were implemented to meet the special needs of families, such as stress management, marital problems, and maternal depression. The intervention continued through adolescence, with new components adapted to the changing development of children and families. Results of this programme indicated that it was successful at the end of first grade and third grade in improving outcomes across a number of different domains, including parenting and child peer relations, emotional understanding, and reading skills. Specifically, parents showed less physical discipline, more consistent and appropriate discipline, and more warmth and positive involvement in their child’s school.^{(24, 26, 27)}