NCT06173752 · Mclean Hospital
Mechanisms of Exposure Therapy for OCD
What this study is about
Exposure therapy is the most effective treatment available for obsessive compulsive disorder, yet up to 50% of patients do not recover because the mechanisms underlying successful response are poorly understood, leading to significant variability in how clinicians conduct exposure therapy.
View original scientific description
Exposure therapy is the most effective treatment available for obsessive compulsive disorder, yet up to 50% of patients do not recover because the mechanisms underlying successful response are poorly understood, leading to significant variability in how clinicians conduct exposure therapy. The main purpose of this study is to determine which target mechanisms are most critical to engage in real-world exposure sessions to produce good treatment outcomes. Adult participants (N = 400) with Obsessive Compulsive Disorder (OCD) receiving exposure therapy from two sites (McLean Hospital, San Diego State University) across the continuum of care (outpatient, partial hospital, residential) will complete baseline clinical and demographic measures as well as weekly symptom reports. The project will measure exposure mechanisms across three levels of analysis (self-report, observer-rated behavior, physiology) during each exposure session. Mechanisms assessed will include a broad range of variables based on both habituation and inhibitory learning models of exposure. Self-report and observer-rated mechanisms will be measured with the Exposure Feedback Form, created and piloted by the study team. Physiological mechanisms will include skin conductance response, heart rate, and heart rate variability measured with a wristwatch. The current study will determine (1) which exposure mechanisms lead to favorable clinical outcomes, and (2) what makes a good exposure for whom. Results of this study have the potential to improve personalized care for the many patients who do not remit following exposure therapy for OCD.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Between the ages of 18-65 years old
- Seeking exposure treatment at McLean Hospital OCD Institute or San Diego State University
- Have a diagnosis of OCD
- Able to complete study measures and treatment procedures in English
Exclusion criteria
- Acute symptoms of psychosis
- Active suicidality (plan, means, intent and/or suicide attempt in past 3 months)
- Presence of co-occurring symptoms that warrant higher level of care (e.g., inpatient treatment)
- Presence of any medical, psychiatric, or developmental condition that would prevent patients from completing assessments or exposure exercises (e.g., non-verbal autism spectrum disorder)
Where
- San Diego, California
- Belmont, Massachusetts
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 25, 2026 · Source of record for eligibility and locations