A Single-Component CBT for GAD

Behavioural Experiments for Intolerance of Uncertainty: A Single-Component Treatment for Generalized Anxiety Disorder

Generalized Anxiety Disorder (GAD) is a chronic condition that is characterized by excessive and uncontrollable worry and anxiety. In Canada, 3 to 4% of the population suffer from GAD at any point in time. These individuals have a lowered quality of life and are at risk for many medical conditions such as coronary heart disease and cancer. Research suggests that both pharmacological and psychological approaches are effective for treating GAD in the short-term; however, psychological treatments appear to offer the greatest long-term benefits. There exist a number of effective psychological treatments for GAD, most of which fall into the category of cognitive-behavioural therapy or CBT. In the 1990s, a group of Canadian investigators developed a CBT protocol for GAD that included four components. Data from five clinical trials suggest that one of the four components is particularly important for treatment success: experiencing uncertainty rather than avoiding it in everyday life. Stated differently, learning to tolerate and deal with uncertainty appears to be the key to decreasing worry and anxiety. Given this finding, the investigators have developed a new treatment that exclusively targets intolerance of uncertainty: Behavioural Experiments for Intolerance of Uncertainty or BE-IU. The goal of the current proposal is to test the efficacy of BE-IU by comparing it to a Waiting List (WL) control condition. A total of 50 participants with a primary diagnosis of GAD will be randomly assigned to either BE-IU or WL and will be assessed at 5 time points ranging from pre-treatment to 12-month follow-up. The conditions will be compared in terms of treatment efficacy and mechanisms. The investigators will also examine the predictors of change during the 12-months following treatment. The proposed study will produce data on the efficacy and mechanisms of a treatment for GAD that is less costly, less complex and easier to disseminate than treatments that are currently available.

Study Overview

• Status: Completed
• Conditions: Generalized Anxiety Disorder
• Intervention / Treatment: Behavioral: Behavioural experiments for intolerance of uncertainty (BE-IU)

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Quebec
    • Gatineau, Quebec, Canada, J8X 3X7
      • Universite du Quebec en Outaouais

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1) at least 18 years of age; 2) principal diagnosis of GAD; 3) no change in medication type or dose in 4 to 12 weeks before study entry (4 weeks for benzodiazepines, 12 weeks for antidepressants and hypnotics); 4) willingness to keep medication status stable while participating in the study; 5) no use of herbal products known to have CNS effects in the 2 weeks before study entry; 6) no evidence of suicidal intent (based on clinical judgement); 7) no evidence of current substance abuse, current or past schizophrenia, bipolar disorder or organic mental disorder; 8) no current participation in other trials; 9) no concurrent psychotherapy during treatment phase of trial; 10) no evidence of anxiety symptoms due to a general medical condition based on clinical judgement (e.g., clinical hyperthyroidism, hypoglycaemia, anaemia).

Exclusion Criteria:

-

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Behavioural experiments (CBT); Behavioural experiments involve selecting a specific thought to be tested (e.g., "uncertainty makes me unable to act") and designing a detailed experiment to test out the thought.	Behavioral: Behavioural experiments for intolerance of uncertainty (BE-IU); Other Names: CBT
No Intervention: Waiting list; 12 week wait (with assessments) before being transferred to the experimental condition.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Clinician's Severity Rating (CSR) of Anxiety Disorders Interview Schedule (ADIS)	Structured diagnostic interview	12 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Penn State Worry Questionnaire (PSWQ)	Self-report questionnaire	12 weeks
Worry and Anxiety Questionnaire (WAQ)	Self-report questionnaire	12 weeks
Beck Anxiety Inventory (BAI)	Self-report questionnaire	12 weeks
Beck Depression Inventory-II (BDI-II)	Self-report questionnaire	14 weeks

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intolerance of Uncertainty Scale (IUS)	Self-report questionnaire	14 weeks
Safety Behaviours Questionnaire (SBQ)	Self-report questionnaire	14 weeks
Heart rate variability (HRV)	Heart rate monitoring with chest strap and Polar watch	14 weeks
Acceptance and Action Questionnaire-2 (AAQ-2)	Self-report questionnaire	14 weeks
Pain Catastrophizing Scale (PCS)	Self-report questionnaire	14 weeks
Pittsburgh Sleep Quality Index (PSQI)	Self-report questionnaire	14 weeks

Collaborators and Investigators

• Sponsor: Universite du Quebec en Outaouais
• Collaborators: Canadian Institutes of Health Research (CIHR); University College, London; Concordia University, Montreal
• Investigators: Principal Investigator: Michel J Dugas, Ph.D., Universite du Quebec en Outaouais

Publications and helpful links

General Publications

• Dugas MJ, Sexton KA, Hebert EA, Bouchard S, Gouin JP, Shafran R. Behavioral Experiments for Intolerance of Uncertainty: A Randomized Clinical Trial for Adults With Generalized Anxiety Disorder. Behav Ther. 2022 Nov;53(6):1147-1160. doi: 10.1016/j.beth.2022.05.003. Epub 2022 May 27.

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2015
• Primary Completion (Actual): October 1, 2018
• Study Completion (Actual): October 1, 2018

Study Registration Dates

• First Submitted: September 15, 2015
• First Submitted That Met QC Criteria: September 15, 2015
• First Posted (Estimate): September 16, 2015

Study Record Updates

• Last Update Posted (Actual): June 5, 2020
• Last Update Submitted That Met QC Criteria: June 4, 2020
• Last Verified: June 1, 2020

More Information

Terms related to this study

• Keywords: Cognitive-behavioural therapy
• Additional Relevant MeSH Terms: Mental Disorders; Anxiety Disorders
• Other Study ID Numbers: UQuebecOutaouais