Transdiagnostic Individual Behavioral Activation and Exposure Therapy

Anxiety and unipolar depression are highly debilitating and commonly co-occurring in young adolescents with lifetime prevalence rates estimated at 8.4% for major depression or dysthymia and at 31.4% for any anxiety disorder in youth ages 13-14 (Merikangas et al., 2010). Cognitive and behavioral therapies (CBT) have received strong support for reducing distress in youth (Silverman, Pina, \& Viswesvaran, 2008; David-Ferdon \& Kaslow, 2008), but efficacy rates peak around 50-70% for anxiety and less for depression. Evidence is accumulating that "transdiagnostic" behavioral therapies that address multiple problems at the same time can enhance treatment outcomes by targeting the mechanisms that underlie commonly co-occurring problems, like anxiety and depression (Chu, Temkin, \& Toffey, 2016; Temkin, Yadegar, Laurine, \& Chu, in press). Furthermore, consolidated transdiagnostic treatment protocols can provide the same level of clinical benefit while delivering active components in a more efficient package, which can increase treatment efficiency and potentially make it easier to train novice clinicians in the future (Chu, 2012; Ehrenreich \& Chu, 2013). While the evidence-base is growing for adult conditions, transdiagnostic interventions have been examined less in child and adolescent populations. Our team has demonstrated the efficacy of a school-based group transdiagnostic intervention that made use of behavioral activation (BA) and exposure therapy to address anxiety and depression for middle-school youth (Chu, Crocco, Esseling, Areizaga, Lindner, \& Skriner, 2016). BA refers to a set of interventions that teach youth how to assess which stressors trigger avoidant coping responses in their lives (i.e., functional assessment) and learn how to address problems with pro-active problem solving strategies. Exposure therapy refers to a set of behavioral interventions that foster new learning tendencies by encouraging and reinforcing contact with the situations that scare individuals. Both sets of strategies have received substantial support in treating youth anxiety and depression. The Chu et al., (2016) trial demonstrated that these two treatment components could be combined and effectively treat a sample of youth reporting either anxiety or depression.

The Chu et al. (2016) study was novel because most forms of evidence-based treatment have been designed as "single disorder" protocols, such that the interventions were designed to target one clinical problem at a time. The current trial takes the following innovative steps. The study will: (a) adapt the Chu et al. group-based protocol to an individual format, (b) deliver the program in a clinical outpatient setting, and (c) utilize three comparison conditions, including a wait-list control and two active psychological interventions. The two active interventions will be single disorder cognitive behavioral therapies (CBT) that were designed to specifically address either youth depression (Primary and Secondary Control Enhancement Therapy; PASCET; Weisz, Thurber, Sweeney, Proffitt, \& LeGagnoux, 1997) or youth anxiety (Coping Cat; Kendall, 1994; Kendall et al., 1997). Both have received substantial support in the literature for supporting clinical improvements in brief individual formats (12 - 16 weeks). By comparing Individual Behavioral Activation Therapy (IBAT) to each of these active interventions, the study aims to demonstrate (a) superior treatment outcomes to wait-list control, (b) comparable treatment outcomes to PASCET and Coping Cat, and (c) differential mediator effects across the four conditions. Findings will provide support for the feasibility, acceptability, and efficacy of IBAT and provide conceptual support for its purported mediators of change.

The current study is a Randomized Controlled Trial (RCT), comparing a novel behavioral intervention (Individual Behavioral Activation Therapy, IBAT) against two established cognitive-behavioral interventions (Coping Cat, PASCET) and a 14-week waitlist (WL) control. Participants will be 160 youth (ages 9-16 years old) who receive a diagnosis of a Diagnostic and Statistical Manual - 5th edition (DSM-5; APA, 2013) anxiety or depression disorder and their caregivers. Participants will be randomly assigned evenly to each of four conditions. The study intends to recruit participants within a 2.5-year period and complete all active participant participation within 3 years.

Specific aims include the following:

Aim 1 - Treatment Efficacy: To evaluate differences in treatment outcomes across IBAT, PASCET, CC, and WL conditions across pre-, mid-, and post-treatment in treatment efficacy, focusing on key diagnostic and symptom outcomes (i.e., CGI, principal diagnosis presence to absence and clinical severity, RCADS anxiety and depression scores, MASC, CESD).

Hypothesis 1: IBAT will produce superior outcomes to 14-week WL control

Hypothesis 2: The three active treatment conditions (IBAT, PASCET, CC) will demonstrate superior treatment outcomes to 14-week WL control, but will not be different from each other.

Aim 2 - Mediator Analysis: To examine the strength of putative mediators in explaining the effects of active treatments (IBAT, CC, PASCET) in comparison to the 14-week WL and in comparison to each other. Putative mediators will include multiple domains: (a) youth socio-emotional functioning (cognitive, behavioral, and affective responses), (b) distress tolerance as assessed by computer tasks, (c) family environment and interactions, (d) caregiver distress and functioning, (e) client and therapist perception of psychotherapy process, (f) ecological momentary assessment and passive sensor data.

Hypothesis 3: Each domain will prove to provide significant mediators for each treatment in comparison to the WL control.

Hypothesis 4: Cognitive mediators will prove to provide significant mediation of CC and PASCET treatment effects, but not necessarily for IBAT.

Hypothesis 5: Distress tolerance will prove to provide significant mediator for IBAT treatment effects, but not necessarily for CC or PASCET.

Aim 3. Note patterns of additional youth mental health services and auxiliary services that families seek beyond treatment received at the Youth Anxiety and Depression Clinic.