Enhancing the reach and impact of parenting interventions for toddler externalising and aggressive behaviours

Childhood externalising behaviours are associated with significant impairments in functioning and long-term negative outcomes. Physical aggression in the toddler years is both common and developmentally normal, however, longitudinal research shows that frequent physical aggression is highly stable over time and is a more robust risk factor for offending in adolescence and adulthood than other externalising behaviours. This thesis is concerned with enhancing the reach and impact of parenting interventions for toddler externalising and aggressive behaviour. Thirty years of research has demonstrated the efficacy of social learning based parenting interventions, typically 8 to 12 sessions in duration, for reducing externalising behaviour problems in childhood. However, the length of standard parenting interventions may overburden families and lead to low participation rates and high attrition rates; it may also prevent primary care health practitioners from implementing them as prescribed. Brief parenting interventions, delivered as part of a stepped care approach, may have the potential to increase the reach of parenting interventions and in turn, impact on externalising behaviour problems at the population level. This thesis reports on the findings of a randomised controlled trial which compared a standard 8 session parenting intervention to a brief 3 session intervention and a waitlist control group for reducing toddler externalising and aggressive behaviours, dysfunctional parenting and related aspects of parent functioning. Sixty-nine self-referred families with a toddler with aggressive behaviour were randomised to the respective conditions. At post-assessment, families who received the 8 session intervention showed significantly lower levels of observed child aversive behaviour, mother-rated child externalising and aggressive behaviours, dysfunctional parenting and higher levels of behavioural self-efficacy compared with waitlist. Families who received the 8 session intervention also reported lower levels of mother-rated dysfunctional parenting compared with those who received the 3 session intervention. Families who received the 3 session intervention differed from waitlist on one measure of mother-rated dysfunctional parenting. No significant group differences emerged at post-assessment for measures of parental negative affect or satisfaction with the partner relationship according to mothers, or for any father-rated measures (with the exception of behavioural self-efficacy). By six month follow-up, families who received the 8 session intervention did not differ significantly from families who received the 3 session intervention on any measure. Both mothers and fathers who received the 8 session intervention were significantly more satisfied with the intervention than those who received the 3 session intervention. Overall, the findings show greater short-term impacts of the 8 session relative to the 3 session intervention. However, medium effect sizes were found for the brief parenting intervention relative to waitlist for child aggressive behaviour and dysfunctional parenting. These effect sizes were similar to those reported in the literature for longer parenting interventions but the current study was underpowered to detect such effects. While this study provides some initial evidence that a brief parenting intervention may have significant effects on dysfunctional parenting, and may offer promise as the first step in a stepped care models of delivery, further research is needed