LINKING SESSION FOCUS TO TREATMENT OUTCOME IN EVIDENCE-BASED TREATMENTS FOR ADOLESCENT SUBSTANCE ABUSE

Psychotherapy process research plays an integral role in the development of empirically based treatments. Treatment development refers to systematic efforts to test, critique, and revise the theoretical underpinnings and technical ingredients of intervention models in connection with an accumulating research base (Kazdin, 1994; Rounsaville, Carroll, & Onken, 2001). Treatment development relies on process research that can elucidate the mechanisms of change responsible for observed outcome effects: How does a treatment work and what features are essential for its success? (Kazdin, 1999). Process research is also poised to make a substantial contribution to treatment dissemination efforts. The imposing gap between efficacy research (testing therapies under highly controlled conditions to maximize internal validity) and effectiveness research (testing therapies under standard practice conditions to maximize external and ecological validity) has prompted demand for research on transporting treatment models from the lab to the clinic (Nathan, Stuart, & Dolan, 2000; Weisz, Donenberg, Han, & Weiss, 1995). One key to successful transportation will be identifying the specific aspects of efficacious models that are linked with good outcomes—knowing what, exactly, should be transported (Kazdin, 2001). This is particularly true for multicomponent, flexibly delivered models whose clinical look may vary from case to case as therapists attempt to meet the unique needs of each client (Gaston & Gagnon, 1996). The current study investigated specific therapy processes for two empirically supported outpatient treatments for adolescent substance abuse: cognitive–behavioral therapy and family therapy. National surveys and household probability studies conducted within the past decade reveal that adolescent drug use remains a prevalent and serious problem (Department of Health and Human Services, 2000; Gfroerer, 1995; Johnston, O’Malley, & Bachman, 1995; Kilpatrick et al., 2000). To date, family therapy has generated the largest evidence base in the treatment of adolescent drug use and cooccurring symptoms (Stanton & Shadish, 1997; Williams, Chang, & ACARG, 2000). Rigorous empirical studies have shown that family-based therapy can produce engagement and retention of drug users and their families in treatment (Henggeler et al., 1991); reduction or elimination of drug use (Liddle et al., 2001; Waldron, Slesnick, Brody, Turner, & Peterson, 2001); decreased involvement in delinquent activities (Henggeler, Melton, Smith, Schoenwald, & Hanley, 1993); improvement in multiple domains of psychosocial functioning such as school grades, school attendance, and family functioning (Liddle et al., 2000); and increased quality of parenting behavior (Mann, Borduin, Henggeler, & Blaske, 1990; Schmidt, Liddle, & Dakof, 1996). There is also evidence that therapeutic gains maintain at long-term follow-up (Liddle et al., 2001) and that family-based approaches are cost-effective in comparison to treatment as usual (Schoenwald, Ward, Henggeler, Pickrel, & Patel, 1996). A second highly regarded treatment approach for adolescent drug abuse is cognitive–behavioral therapy (Bukstein, 1995; Weinberg, Rahdert, Colliver, & Glantz, 1998). Cognitive–behavioral approaches have demonstrated efficacy in reducing adolescent substance abuse (Waldron et al., 2001; Winters, Latimer, & Stinchfield, 1999) and comorbid psychiatric problems (Kaminer, Blitz, Burleson, & Sussman, 1998). Cognitive–behavioral approaches are also widely practiced with adolescent drug users (Bukstein, 1995), making them a critical target for further empirical validation. This study investigated two manualized treatments for adolescent substance use: individual cognitive–behavioral therapy (CBT) and multidimensional family therapy (MDFT). These models were previously tested in a randomized controlled trial with inner-city, primarily ethnic minority adolescent drug abusers (Liddle & Hogue, 2001). Results of that study indicated that both treatments were effective in reducing marijuana use, externalizing symptoms, and internalizing symptoms at posttreatment and up to 1 year later, with MDFT showing some superiority in producing gains more rapidly and maintaining posttreatment gains at follow-up. The main goals of the current study were to identify differences between CBT and MDFT in the use of specific therapy techniques and to link these process elements to outcomes found in the parent randomized trial. Specific therapy techniques are the technical aspects of a treatment model that derive directly from its fundamental theory- and practice-based principles (Elkin, Pilkonis, Docherty, & Sotsky, 1988). Advances in the technology of psychotherapy process research, including specification of clinically meaningful process variables and use of dimensional scales to measure therapist behavior (Greenberg, 1986; Schaffer, 1982; Sechrest, 1994), have spurred efforts to identify specific techniques that predict treatment outcome. A recent meta-analysis found that the effects of specific therapy components exceeded those of non-specific and facilitative factors, particularly for clients with more severe problems (Stevens, Hynan, & Allen, 2000). Nevertheless, the therapeutic potency of specific techniques (Messer & Wampold, 2002; Wampold et al., 1997), and the theoretical and methodological feasibility of discovering process–outcome correlations involving discrete technique variables (Stiles & Shapiro, 1994), are still in question. This study examined the degree to which individual-focused and family-focused techniques within CBT and MDFT promote change in core behavioral symptoms related to adolescent substance abuse. Both approaches provide for some degree of therapist flexibility in targeting both individual and family functioning in order to achieve treatment goals. CBT focuses on changing the behaviors and cognitions of individual adolescents and works predominantly with teens alone in session. However, CBT therapists are trained to discuss salient issues pertaining to the youth’s relationships with parents and family members and, also, to meet periodically with care-givers. In the same vein, whereas MDFT targets family interactions directly and works predominantly with caregivers and other family participants in session, MDFT therapists also routinely hold individual sessions and work on the personal attitudes and behaviors of teens. There are two primary study hypotheses: Greater use of adolescent-focused intervention techniques will predict improvement in CBT, whereas greater use of family-focused techniques will predict improvement in MDFT. Adolescent outcomes in drug use, externalizing symptoms, and internalizing symptoms were measured at pre- and posttreatment. Therapy techniques were measured using observational scales from a psychotherapy process instrument developed in a previous study on this sample (Hogue et al., 1998). The current study extended the Hogue et al. 1998 study by adding new items to the observational scales, conducting new exploratory factor analyses of the expanded scale, increasing the number of participants, and conducting process–outcome analyses.