Related Experiment Video
Updated: Apr 16, 2026

Protocol for Repetitive Transcranial Magnetic Stimulation with Symptom Provocation to Treat Obsessive-compulsive Disorder
Published on: November 25, 2025
Treating Treatment-Resistant Patients with Panic Disorder and Agoraphobia Using Psychotherapy: A Randomized
Andrew T Gloster1, Rainer Sonntag, Jürgen Hoyer
1Institute of Clinical Psychology and Psychotherapy, Technische Universität Dresden, Dresden, Germany.
Abstract:
Background: Nonresponsiveness to therapy is generally acknowledged, but only a few studies have tested switching to psychotherapy. This study is one of the first to examine the malleability of treatment-resistant patients using acceptance and commitment therapy (ACT). Methods: This was a randomized controlled trial that included 43 patients diagnosed with primary panic disorder and/or agoraphobia (PD/A) with prior unsuccessful state-of-the-art treatment (mean number of previous sessions = 42.2). Patients were treated with an ACT manual administered by novice therapists and followed up for 6 months. They were randomized to immediate treatment (n = 33) or a 4-week waiting list (n = 10) with delayed treatment (n = 8). Treatment consisted of eight sessions, implemented twice weekly over 4 weeks. Primary outcomes were measured with the Panic and Agoraphobia Scale (PAS), the Clinical Global Impression (CGI), and the Mobility Inventory (MI). Results: At post-treatment, patients who received ACT reported significantly more improvements on the PAS and CGI (d = 0.72 and 0.89, respectively) than those who were on the waiting list, while improvement on the MI (d = 0.50) was nearly significant. Secondary outcomes were consistent with ACT theory. Follow-up assessments indicated a stable and continued improvement after treatment. The dropout rate was low (9%). Conclusions: Despite a clinically challenging sample and brief treatment administered by novice therapists, patients who received ACT reported significantly greater changes in functioning and symptomatology than those on the waiting list, with medium-to-large effect sizes that were maintained for at least 6 months. These proof-of-principle data suggest that ACT is a viable treatment option for treatment-resistant PD/A patients. Further work on switching to psychotherapy for nonresponders is clearly needed. © 2015 S. Karger AG, Basel.
More Related Videos
Related Concept Videos
Panic Disorder
Behavior Therapy
Exposure therapy is a cornerstone of behavioral treatment for anxiety disorders. It involves systematic exposure to feared stimuli, either in real...
Crossover Experiments
Crossover designs are performed even with smaller sample sizes since the samples can act as their controls. These are better than simple randomized trials since patients are exposed to all the treatments.
Treatment Strategies for Psychological Disorders
Psychological therapies focus on modifying emotions, thoughts, and behaviors through talking, interpreting, listening, rewarding, challenging, and modeling. Clinical psychologists, counselors, and social workers commonly practice psychotherapy. Clinical...
Psychosis: Goals of Pharmacotherapy
Generalized Anxiety Disorder

