Efficacy and predictors of outcome in parent training interventions for children with conduct problems

摘要

Aggressive and disruptive behaviors in childhood are one of the most common reasons for referral to child psychiatric clinics and are predictive of a range of negative health outcomes later in life. The present thesis comprises four studies of parent training (PT) interventions targeting conduct problems (CP) in children aged 3 to 12. The main objectives were to evaluate issues pertaining to short- and long-term effects, dissemination modalities (Internet-based and face-to-face delivery) and predictors of change. Study I was a randomized controlled trial including parents of 104 children who were allocated to either an Internet-based PT program or a waitlist condition. At post-test, intervention families had improved significantly in parent-reported child CP and parenting practices, compared with waitlist families. Between-group effects sizes were in the moderate range for CP reductions, i.e., similar to effects commonly reported in meta-analyses of face-to-face PT programs. Study II concerned prediction of outcome for intervention families in the study-I sample. Results showed that children with elevated levels of callous-unemotional (CU) traits benefitted less from the Internet-based PT program, compared with low-CU children, despite the fact that parents of high-CU children reported increased use of positive/praiseful parenting, as well as decreased use of harsh parenting, following participation in the Internet-based PT program. Study III employed an 18-month follow-up of intervention families (from the study-I sample) showing further improvements of child CP and mostly maintenance of treatment gains in other domains (e.g., hyperactivity and prosocial behaviors). Within the same study, associations between homework compliance and outcomes were investigated. Results indicated that higher parental engagement in homework tasks related to conflict management (ignoring misbehavior and time out) was associated with greater reductions of child CP, compared to less engagement in homework assignments. Study IV compared the effectiveness of four group-based PT programs (Comet, Incredible years, Cope and Connect), including behavioral as well as non-behavioral interventions, at a 2-year follow-up. Participants were parents of 749 children who had been randomly allocated to one of the PT programs. At follow-up, children in all four conditions had improved to a similar extent with regard to child CP, hyperactivity and inattention problems, when controlling for baseline severity and age differences. A comparison of change rates, from baseline to the 2-year follow-up indicated that children in behavioral programs were reported to have more rapid reductions of problems during the course of the intervention, compared with children in the non-behavioral program. During the 2-year follow-up period, however, participants in behavioral programs were mostly characterized by maintenance of previous treatment gains, whereas participants in the non-behavioral program continued to improve. In conclusion, the current thesis provides support for the short- and long-term efficacy of an Internet-based PT program, suggesting that online dissemination of interventions targeting child CP could be an alternative to face-to-face PT. The findings also highlights the predictive role of child CU traits in PT programs, emphasizing the need for different treatment approaches, for the subgroup of children who present with a combination of CP and CU traits. The current thesis also provides support for the long-term effectiveness of four group-based PT programs, when employed in Swedish routine care settings. This finding should be important for future guidelines and recommendations of PT-program implementation.