2 - (SYM 10) What Did You Learn? Quantifying Mechanistic Activation in Real-world Exposure Therapy Sessions for OCD and Anxiety Disorders

Despite its longstanding status as the treatment of choice for Obsessive Compulsive Disorder (OCD), the mechanisms underlying successful response for Exposure and Response Prevention (ERP) in clinical practice remain poorly understood. While theoretical models of exposure mechanisms are relatively well-developed, methods for measuring these proposed mechanisms in the context of real-world exposure sessions lag behind.

This presentation will describe the development of the McLean Exposure Therapy Engagement & Reflection (METER) form. This clinical tool was designed in partnership with researchers and seasoned clinicians to integrate multiple theories of exposure – habituation, inhibitory learning, and acceptance and commitment – and to distill mechanisms into quantifiable items that can be assessed in session with low patient burden.

 We will present METER data on 5,037 exposure sessions from 578 adult patients (M = 30.0 years) in a partial hospital/residential treatment program for OCD and related disorders (M = 64.0 days length of stay). Patients presented with a mean Yale-Brown Obsessive Compulsive Scale (YBOCS) score of 25.4 (SD = 5.3) at admission. Nearly all exposure mechanisms changed in the expected direction through repeated exposure practice. For example, coping self-efficacy increased (B = .004), willingness to welcome unpleasant internal experiences increased (B = 0.18), and ritualizing during exposures decreased (B = -0.36) across treatment (ps < .001). Changes in these mechanisms were associated with changes in YBOCS scores in the expected direction. Specifically, greater coping self-efficacy (B = -0.36), greater perceived relevance of exposure to the patient’s daily life (B = -0.49), greater willingness (B = -0.03), and reduced ritualizing (B = -0.05), were all associated with lower OCD symptom severity (ps < .001).

The discussion will synthesize research findings alongside clinical lessons learned regarding implementation of this tool. We will provide context and cautions for interpretation of exposure mechanisms data, with an emphasis on determining not just what makes a good exposure, but also what makes a good exposure for whom?