A recent review of randomized trials finds significant evidence for the long-term effectiveness of preventive parenting programs – but it is still unclear why they are effective.

The review, by researchers at the Prevention Research Center in Arizona, had two purposes. First, it aimed to estimate the long-term effectiveness of parenting interventions in preventing an array of developmental difficulties and in promoting competency. Second, it sought to understand the mechanisms or processes by which these kinds of programs are effective.

Several of the programs included in the review are interventions that have been reviewed on Prevention Action, including Incredible Years and the Nurse Family Partnership. Others are less well known, such as Schoolchildren and Their Families and Coping Power.

The review examined the findings of 46 randomized trials of preventive parenting interventions. The studies were selected based on their inclusion of a measure of long-term impact (defined as outcomes assessed at one year or more after the program) and a focus on universal prevention and health promotion. Trials that targeted children with clinical levels of difficulty were not included.

Programs were grouped by their focus on a developmental period: infancy and toddlerhood (0-3), early childhood (4-7), middle childhood (8-12), and adolescence (13-18).

The results provide considerable evidence for the long-term effectiveness of these kinds of programs, with positive impacts on children’s health and development demonstrated from one to 20 years after the program was delivered.

A complicating factor in assessing the long-term effectiveness of parenting programs is that many of the interventions described are multi-faceted, including components such youth-based education and school-based training in addition to promoting parenting support. The review highlights the importance for future research “of identifying combinations of components with maximal effects.”

Two routes to success: parenting behavior or “cascading pathways”?

Multi-faceted interventions also make it difficult to trace the pathways by which the programs are working to effect long-term change. The authors propose two possible routes. The first proposes that the long-term results are due to program effects on parenting behavior (see, for example, OK, so it works, but with whom and how?).

Studies suggest that warm, authoritative and consistent parenting is an effective mechanism for improving a range of “problem behaviors.” In addition, improving parents’ monitoring of and communication with their children leads to better outcomes.

The second proposition suggests that long-term effects are due to changes in “social, cognitive, behavioral, and biological processes in parents and youth, and in the transactions between youth and their social contexts.” Theoretically, this means that the new skills that parents acquire via the intervention are reinforced by positive responses by their children. Improvements in the child’s behavior and well-being heighten parents’ beliefs that they are able to influence their child, leading to greater persistence and mastery of the parenting skills.

Part of this second proposition is the idea that interventions might influence the environmental contexts within which children and young people are involved. Referred to as “cascading pathways,” it suggests that a change in one area or context can trigger a change or progression of change in others.

For example, a child whose behavior saw him previously rejected by peers and teachers at school, may show improvement when better parenting at home leads to less aggression at school and improved friendships. Similarly, better behavior by the child at home may lead to reduced parental depression, which in turn results in better parenting.

At the moment, the evidence does not provide support for one of these pathways over the other because “little research has systematically investigated this issue.” Future randomized trials have the opportunity to build this into the design of the research and to advance effective approaches.

Reference:
Sandler, Irwin N., Erin N. Schoenfelder, Sharlene A. Wolchik, and David P. MacKinnon. 2011. “Long-term impact of prevention programs to promote effective parenting: Lasting effects but uncertain processes.” Annual Review of Psychology 62: 299-329.