Preliminary Findings for Group Transdiagnostic Behavior Therapy for Affective Disorders Among Youths

Participant responses were collected from an outpatient sample at a specialized clinic for assessment and treatment of anxiety disorders in a Canadian hospital setting. Study inclusion criteria included meeting diagnostic criteria for a principal diagnosis of a DSM-5 anxiety disorder, depressive disorder, or posttraumatic stress disorder and being age 16–19. Data collection took place between July 2014 and May 2018 and was concluded due to its long duration, rather than because a specific recruitment target was reached.

All procedures and measures used in this study were approved by the Hamilton Integrated Research Ethics Board at St. Joseph's Healthcare, Hamilton and McMaster University. At the intake appointment, participants provided full informed consent and completed the Diagnostic Assessment Research Tool (11) to establish principal and additional diagnoses for current and lifetime conditions and to establish inclusion criteria for the study treatment. Group TBT consisted of 12 weekly 120-minute manualized group psychotherapy sessions. Groups of six to eight participants were led by two or three clinicians with training in TBT. Clinicians were provided the TBT protocol, were trained by the protocol’s author, and had successfully completed a previous study on group TBT (9). Pre- and posttreatment self-report questionnaires were administered after sessions 1 and 11, respectively. The questionnaire packet included the Depression Anxiety Stress Scales (DASS) (12) to assess symptoms of depression, anxiety, and stress; the Illness Intrusiveness Rating Scale (IIRS) to assess transdiagnostic impairment (13); and the State-Trait Inventory for Cognitive and Somatic Anxiety (STICSA) to assess symptoms of cognitive and somatic anxiety (14).

TBT was developed as a streamlined protocol to teach, prepare for, practice, and master four types of exposure techniques (situational, interoceptive, imaginal, and positive emotional) to reduce transdiagnostic avoidance and lead to symptom remission. We adapted the protocol for the adolescent sample by including a module on self-esteem, by moving the coping statements module earlier in treatment, and by implementing minor changes to the language to make the examples more relevant to adolescents. TBT has received initial support as an individual therapy (7, 8, 10) and as a slightly revised group format (9) in adult samples. The treatment includes psychoeducation on avoidance and related behavioral goal setting (sessions 1–2), psychoeducation and treatment rationale for transdiagnostic exposure (sessions 3–4), and practice and refinement of exposure practices (sessions 5–11). We tailored in-session exposure practices to individual participants or groups of participants (e.g., four participants traveled to a cafeteria for situational exposures; two participants remained in the room for interoceptive exposures). We included the optional modules on coping statements and safety behaviors to further encourage exposure practices in all groups and included other modules as requested by group members (e.g., sleep disruption). TBT concluded with a final session to review treatment progress and relapse prevention strategies (session 12). (A copy of the TBT manual is available upon request.)

Data from the measures administered to all participants (demographic, diagnostic, and self-report measures) were inspected for missing values. Minimal missing data were identified across measures (e.g., no participant was missing >2% of total data; <2% of the total data was missing in the full sample). One participant was missing data from the entire IIRS scale. Given the limited missing data, no participants were excluded from the analyses for significant missing data. We used within-scale mean substitution to replace missing values for participants with minimal missing data, except for the missing IIRS scale for one participant. We used paired sample t tests to investigate overall treatment effects across the DASS scales (depression, anxiety, and stress) and the IIRS and STICSA scales (cognitive and somatic) across all participants. Because of procedural limitations, no data were available on those who did not complete the protocol.

All participants were ages 16–19 (mean±SD=17.6±0.8) and single (N=20, 100%). Most participants reported actively participating in their high school (N=12, 60%) or college (N=4, 20%) education. A majority of the sample was white (N=16, 80%). Participants endorsed symptoms consistent with principal diagnoses of panic disorder (N=10, 50%), generalized anxiety disorder (N=5, 25%), social anxiety disorder (N=4, 20%), or posttraumatic stress disorder (N=1, 5%). The most common comorbid diagnoses were major depressive disorder (N=13, 65%), panic disorder (N=5, 25%), and generalized anxiety disorder (N=4, 20%).

Treatment outcomes, as measured by the DASS, STICSA, and IIRS, are presented in Table 1. Participants demonstrated significant improvements across all outcome measures for anxiety symptomatology, including DASS anxiety and STICSA cognitive and somatic anxiety (t>2.1, p<0.05 for all measures), with moderate effect sizes (Cohen’s d ranged from 0.48 to 0.79). Significant treatment improvement also was observed on the DASS stress scale (t=2.4, p=0.025, d=0.48). No reliable improvements were observed on DASS depression or the IIRS.