The primary purpose of this study was to examine the mechanisms by which an evidence-based treatment of juvenile offenders decreased the antisocial behavior and deviant sexual interest and sexual risk behaviors of juvenile sexual offenders participating in a randomized effectiveness trial. Pertinent antisocial behaviors included criminal offending, substance use, and externalizing problems. Deviant sexual interest and sexual risk behaviors were also examined in light of their hypothesized association with sexual reoffending (Worling & Langstrom, 2006
). Importantly, and consistent with the recommendations of Weersing and Weisz (2002)
pertaining to studies testing mediational models, this effectiveness study focused on real-world clients treated in community-based contexts.
Multisystemic therapy (MST; Henggeler, Schoenwald, Borduin, Rowland, & Cunningham, 1998
) was selected as the evidence-based treatment model examined in this study (Letourneau et al., 2008
) for two main reasons. First, research shows that adolescent sexual offenders have more in common with other delinquents than is generally assumed (Blaske, Borduin, Henggeler, & Mann, 1989
; Butler & Seto, 2002
; Ronis & Borduin, 2007
; van Wijk et al., 2005
). Such findings suggest that effective treatments for delinquency hold promise in treating juvenile sexual offenders. With 10 published randomized trials with delinquents and their families (Henggeler, Sheidow, & Lee, 2007
), MST has relatively well-established effectiveness with this clinical population (National Institutes of Health, 2006
; U.S. Public Health Service, 2001
). Although this conclusion has been disputed by Littell and colleagues (Littell, Popa, & Forsythe, 2005
) in their meta-analysis, the findings of the Littell review have not been replicated in other meta-analyses (Aos, Miller, & Drake, 2006
; Curtis, Ronan, & Borduin, 2004
), and the methodology of that review has been criticized (Henggeler, Schoenwald, Borduin, & Swenson, 2006
; Ogden & Hagen, 2006
). Second, two MST randomized efficacy studies (i.e., graduate students as therapists, an MST treatment developer as supervisor) with juvenile sexual offenders have demonstrated considerable promise (Borduin, Henggeler, Blaske, & Stein, 1990
; Borduin, Schaeffer, & Heiblum, in press
). For example, at a 3-year follow-up (Borduin et al., 1990
), MST was significantly more effective than individual counseling at preventing sexual reoffending (i.e., 12.5% recidivism for MST versus 75% for individual counseling). Together, these outcomes with juvenile offenders in general and juvenile sexual offenders in particular led to the funding of an effectiveness trial (i.e., community-based practitioners and supervisors, minimal exclusion criteria) to examine the effectiveness of MST as adapted for juvenile sexual offenders in a real-world clinical setting. The present report is based on this trial.
The favorable outcomes that MST has achieved with juvenile offenders have been thought to support the model's underlying theory of change. A primary assumption in this theory of change is that adolescent antisocial behavior is driven by the interplay of risk factors associated with the multiple systems in which youth are embedded (Bronfenbrenner, 1979
). This assumption is based largely on decades of correlational and longitudinal research (e.g., Loeber & Farrington, 1998
; U.S. Public Health Service, 2001
) showing that adolescent antisocial behavior is linked with key characteristics of the youth (e.g., poor problem solving skills), the family (e.g., low monitoring, ineffective discipline), peer relations (e.g., association with deviant peers), school functioning (e.g., poor academic performance), and neighborhood context. Thus, to be optimally effective, interventions should have the capacity to address a comprehensive array of risk factors (e.g., association with problem peers), though on an individualized basis (i.e., not all youth and families will have the same risk factors), while concomitantly building protective factors (e.g., parenting effectiveness).
Although the individualized nature of MST has likely facilitated its clinical success, such individualization also decreases the probability that hypothesized mediators of favorable outcomes will evidence significant treatment effects in clinical trials - because those mediators will not be targeted in each and every clinical case. Hence, in examining possible mediators of favorable MST outcomes, analyses that focus on measures of those constructs most central to the MST theory of change are most likely to be fruitful. For MST, caregivers have been viewed as the main conduits of change. MST, therefore, focuses on empowering caregivers to gain the resources and skills needed to be more effective (i.e., improved monitoring, supervision, discipline) with their children. Then, as caregiver effectiveness increases, the therapist guides caregiver efforts to prevent antisocial behavior (e.g., by disengaging their children from deviant peers). Although the logic of this perspective seems relatively compelling and the targeted variables fit with key factors that sustain antisocial behavior in adolescents, the MST theory of change with juvenile offenders has not been tested in a formal mediational study.
MST is not alone among evidence-based practices that have few rigorous tests of their underlying theories of change (Kazdin, 2007
; Weersing & Weisz, 2002
). Nevertheless, at least for evidence-based interventions for youth antisocial behavior, the small extant literature supports the pivotal roles played by caregivers and peers. In a study of Multidimensional Treatment Foster Care (MTFC; Chamberlain, 2003
) in which juvenile offenders received either MTFC or group home care, Eddy and Chamberlain (2000)
showed that the positive effects of MTFC on adolescent criminal activity were mediated by improved caregiver behavior management practices and decreased adolescent association with deviant peers. Similarly, in an indicated prevention trial of the Coping Power program with at-risk preadolescent boys, Lochman and Wells (2002)
found that parental inconsistent discipline was a key mediator of subsequent youth antisocial behavior outcomes. These results are consistent with MST findings from two separate clinical trials with juvenile offenders showing that the degree of therapist adherence to the MST protocol was associated with improved family relations and decreased deviant peer affiliation, which, in turn, were associated with decreased delinquent behavior (Huey, Henggeler, Brondino, & Pickrel, 2000
). Although these findings are consistent with the MST theory of change, Huey et al. (2000)
did not include the types of formal mediational tests (i.e., the control groups in the pertinent studies were not included in the analyses) recommended by reviewers (Kazdin, 2007
; Weersing & Weisz, 2002
). The present study aims to build on this budding area of research by examining family and peer variables as mediators of positive MST effects with juvenile sexual offenders.
Two methodological and conceptual points are particularly pertinent to the design and conduct of this study. First, as emphasized by reviewers (e.g., Worling & Langstrom, 2006
), juvenile sexual offenders have low rates of recidivism. Hence, for the 1-year post recruitment follow-up examined in the present study, it was not possible to include sexual reoffending as a key outcome variable. Thus, in addition to measures of antisocial behavior in general, deviant sexual interest and sexual risk behaviors were used as outcome indices. These behaviors are well-supported risk factors for adult sexual offender recidivism (e.g., Hanson & Bussiere, 1998
) and widely hypothesized predictors of juvenile sexual reoffending (Worling & Langstrom, 2006
), though the latter association has not been demonstrated empirically (Letourneau & Miner, 2005
). Second, as noted throughout the manuscript, we have endeavored to address the multiple requirements for demonstrating mediators and mechanisms of change originally proposed by Hill (1965)
and recently summarized by Kazdin (2007)
. These requirements include the usually expected associations between the treatment, mediators, and outcomes in the context of a randomized clinical trial (Baron & Kenny, 1986
); specificity (i.e., only a subset of plausible mediators account for therapeutic change); consistency of results with similar studies; demonstration of a timeline between cause and effect; and the plausibility of the findings.
In sum, this study tested the theory of change of an evidence-based treatment of juvenile offenders within the context of a randomized effectiveness trial conducted with juvenile sexual offenders and their families. Specifically, key aspects of family relations and peer relations were examined as mediators of antisocial behavior outcomes in general and sexual problem outcomes in particular.