The main finding of this study is that success in treating adolescent drug abuse and cooccurring symptoms was related to in-session focus on family-related treatment themes. Moreover, the benefits of focusing on family-related content and themes were as strong within individual cognitive–behavioral therapy as within multidimensional family therapy. These findings are in accord with the consensus that family conflict, parent–child detachment, and deficient parenting skills are primary etiologic factors for adolescent substance use (Repetti, Taylor, & Seeman, 2002
) and are thus logical targets of treatment. Overall, results underscore the critical importance of attending to family risk and protective factors in the treatment of adolescent drug use, regardless of the particular theoretical orientation of the therapist.
Results also suggest a partial yet intriguing explanation for the relative superiority of family-based approaches in treating adolescent drug abuse (Williams et al., 2000
): They are, at the very least, sure to make family-related issues central to the treatment agenda. It is true that family interaction techniques, a specific type of family therapy technique that engages family members as cotargets of therapeutic activity during conjoint sessions, are the traditional foundation of most family therapy models. In this study, however, interventions that targeted family themes, but not those that required family member participation in session, predicted treatment gains. This was true in the family condition as well as the individual condition. These findings do not imply that interaction techniques can be deemed expendable or second-class features of family therapies for teen drug problems. Rather, they contribute to the sparse literature on parent–family involvement in therapy with adolescents (Weisz & Hawley, 2002
) and underscore the fact that family involvement in childhood treatments is a continuum that can vary in scope and intensity, depending on the nature of the disorder and the treatment model being applied (Fauber & Long, 1991
It was surprising that family-focused interventions predicted outcomes across the board in individual therapy, particularly given that CBT therapists used them much less extensively than adolescent-focused interventions. Specifically, CBT sessions with the highest ratings for family content techniques (one standard deviation above the mean) registered on average below mid-point of the scale, falling roughly at the “Somewhat” anchor. Apparently, though used sparingly, they were used to great effect. Note that exploring family-related themes in session, especially at a moderate level, was permitted by the CBT protocol and was not an adherence violation. Results do not imply that family-focused techniques were the primary therapeutic agent in these CBT cases, only that, all other things being equal, cases with more family focus tended to have better outcomes. Also, these findings do not diminish the theoretical and clinical significance of well-articulated adolescent-focused interventions for effectively implementing both CBT and MDFT. In fact, it may well be true that a certain threshold of adolescent-focused techniques, in addition to focus on family themes, is required for treatment success in both models. Certainly, therapists in both conditions used greater mean levels of individual techniques than family techniques, even though use of individual techniques did not vary with treatment outcome.
This study attempts to advance knowledge about implementing evidence-based treatments for adolescent drug abuse, a pervasive psychological disorder and public health problem. Both study conditions were manualized treatments with excellent fidelity. There were few differences between therapists within conditions in utilizing specific techniques and no differences in outcome success; also, there was no evidence that therapists adjusted their utilization in response to pretreatment symptom levels. In these respects, the study demonstrated high internal validity. Some have argued that tight control of the treatment variable in randomized trials reduces the possibility of finding process–outcomes correlations because variance in implementation is stripped away (Gaston & Gagnon, 1996
). Even so, medium-to-large effects were observed.
Given the small sample size, care was taken to identify and remove multivariate outliers that unduly influence observed relations among variables. Nonetheless, the study design was limited by sample size, primarily in the need to conduct exploratory rather than confirmatory factor analysis of the empirical factor structure of the TBRS. Also, liberties were taken in interpreting trend-level effects (p
s < .10), which was considered justifiable in light of the sample size, the medium-to-large effect sizes for all process–outcome correlations, and the inherently conservative nature of using multiple regression to model interaction effects for field data (McClelland & Judd, 1993
). Because the design was not purely experimental—the extent of adolescent focus and family focus was not randomly assigned to cases—it cannot be ruled out that those clients who evoked more family focus in session were also those more inclined to improve. Finally, results must be deemed preliminary until confirmed with larger samples and long-term outcome assessments.
Because the study did not measure therapeutic alliance, therapist competence, or other psychotherapy common factors, the study cannot directly enter the debate about the relative importance of specific versus common elements (for recent position papers, see Beutler, 2002
, and Messer & Wampold, 2002
), nor can we rule out the possibility that common factors were a third-variable influence working behind the scenes to bolster observed technique–outcome relations. Still, results favor the contention that specific therapy techniques can directly facilitate client improvement within the context of theory driven, flexibly applied treatments for specified populations (Beutler, 2002
; Sechrest, 1994
), perhaps especially for clients with more severe impairment (Stevens et al., 2000
). More important, the findings suggest a tangible option for real-world therapists who prefer working alone with adolescents and face insurmountable barriers to including family members in treatment for adolescent drug problems: incorporate work on family themes into treatment plans. This simple directive, if verified by future studies, may prove to be a valuable common ingredient in the training protocols of research groups who hope to disseminate empirically supported treatments and train front-line clinicians to deliver either individual-based or family-based approaches for adolescent drug abuse.