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Testing Beliefs About Uncertainty in the Treatment of Generalized Anxiety Disorder

Challenging Uncertainty: Behavioural Experiments in the Treatment of Generalized Anxiety Disorder

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01958788
Enrollment
7
Registered
2013-10-09
Start date
2013-09-30
Completion date
2014-12-31
Last updated
2016-02-23

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Generalized Anxiety Disorder

Keywords

Cognitive-behavioral treatment, Generalized anxiety disorder, Worry, Behavioral experiments, Safety behaviors, Anxiety

Brief summary

Generalized Anxiety Disorder (GAD) is an anxiety disorder characterized by excessive and uncontrollable worry. Our research group has developed a cognitive-behavioural treatment (CBT) for GAD centered upon intolerance of uncertainty, a dispositional characteristic that arises from a set of negative beliefs about uncertainty and its consequences (Dugas & Robichaud, 2007). This CBT protocol has demonstrated good efficacy over four previous clinical trials: approximately 70% of participants fully remit from GAD following treatment and maintain these gains over extended follow-up periods. These results, while positive, do suggest that a substantial minority of individuals do not fully benefit from the existing treatment protocol. Across our randomized clinical trials, individuals who do not achieve diagnostic remission of GAD continue to endorse elevated levels of intolerance of uncertainty. This suggests that the current CBT protocol does not effectively reduce intolerance of uncertainty in some treated individuals. To address this, we have developed a modified version of the original CBT protocol that targets intolerance of uncertainty more directly. The goal of the current proposal is to determine whether this newly developed CBT protocol with fewer components can deliver comparable or superior GAD symptom reduction. A total of 7 participants with a primary diagnosis of GAD received the newly developed CBT protocol over 12 weekly sessions. Measures of GAD symptoms, psychopathology, and intolerance of uncertainty were administered at pre-, mid-, and post-treatment, as well as at 3- and 6-month follow-ups. The proposed study will provide information about the efficacy of this new CBT protocol in reducing GAD symptoms.

Detailed description

Generalized anxiety disorder (GAD) is characterized by excessive and uncontrollable worry and anxiety. This common and debilitating anxiety disorder is associated with significant distress as well as substantial impairment in occupational, social, and daily functioning. As a result, effective treatment for GAD is essential. Several cognitive-behavioural treatment (CBT) protocols have been developed for GAD, including an efficacious treatment developed by our research group. This CBT protocol for GAD centres upon intolerance of uncertainty, a dispositional characteristic that arises from a set of negative beliefs about uncertainty and its consequences (Dugas & Robichaud, 2007). Previous research has shown that individuals with GAD demonstrate high intolerance of uncertainty, and that there are a number of potential pathways by which intolerance of uncertainty may lead to symptoms of GAD (see Dugas & Robichaud, 2007 for a review). Our CBT protocol targeting intolerance of uncertainty has demonstrated good efficacy across four published randomized clinical trials: approximately 70% of participants have fully remitted from GAD following treatment and have maintained these gains over extended follow-up periods. These results, while positive, do suggest that a substantial minority of individuals do not fully benefit from the existing treatment protocol. Across our randomized clinical trials, individuals who do not achieve diagnostic remission of GAD continue to endorse elevated levels of intolerance of uncertainty. This suggests that the current CBT protocol does not effectively reduce intolerance of uncertainty in some treated individuals. Additionally, the existing treatment protocol has 6 major components, utilizes a number of cognitive and behavioural techniques (including symptom monitoring, motivational interviewing, situational exposure, problem-solving training, and imaginal exposure), and requires at least 14 sessions to implement. Recent literature (e.g., Cougle et al., 2011) has suggested that there is increased need for parsimony and efficiency in CBT protocols. As a result, our research group is investigating new methods of targeting intolerance of uncertainty that demonstrate greater parsimony and efficiency. Our previous CBT protocol for GAD targeted intolerance of uncertainty directly through situational exposure, and indirectly through motivational interviewing, problem-solving training, and imaginal exposure. In an effort to streamline and strengthen GAD treatment, the newly developed CBT protocol only targets intolerance of uncertainty directly. In this new CBT protocol, intolerance of uncertainty was targeted using behavioural experiments in which participants identified and tested out their beliefs about uncertainty. The extant literature suggests that behavioural experiments are an efficacious way to target the emotional, cognitive, and behavioural components of anxiety disorders and may be superior to habituation-based exposure paradigms (McMillan & Lee, 2010; Salkovskis et al., 2007). The current study examined if a newly developed CBT protocol with fewer components could deliver comparable GAD symptom reduction. Seven (7) individuals with a primary diagnosis of GAD completed 12 sessions of CBT using a newly developed treatment protocol focusing exclusively on intolerance of uncertainty. The treatment consisted of 50-minute, weekly sessions targeting intolerance of uncertainty primarily via behavioural experiments. The three treatment components included: (1) psychoeducation and uncertainty awareness training; (2) testing beliefs about uncertainty (via behavioural experiments); and (3) relapse prevention. Measures of GAD symptoms, general psychopathology, and intolerance of uncertainty were administered at pre-, mid-, and post-treatment, as well as at 3- and 6-month follow-ups. Our main outcomes of interest were effect sizes (i.e., relative magnitude of change from pre-posttreatment, pretreatment to 6-month follow-up, and posttreatment to 6-month follow-up).

Interventions

BEHAVIORALCognitive-Behavioural Treatment

12 weekly sessions of individual cognitive-behavioural treatment (CBT) targeting intolerance of uncertainty.

Sponsors

Canadian Institutes of Health Research (CIHR)
CollaboratorOTHER_GOV
Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal
CollaboratorOTHER
Concordia University, Montreal
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Primary diagnosis of GAD (as assessed by semi-structured clinical interviews) * Score of 58 or greater on the (Intolerance of Uncertainty Scale) * Willingness to keep medication status stable while participating in the study

Exclusion criteria

* Change in medication type or dose in 12 weeks before study entry * Use of herbal products known to have central nervous system effects in the 2 weeks before study entry * Evidence of suicidal intent * Evidence of current substance abuse * Evidence of current or past schizophrenia, bipolar disorder or organic mental disorder * Current participation in other trials * Concurrent psychotherapy during treatment phase of trial * Evidence of anxiety symptoms due to a general medical condition

Design outcomes

Primary

MeasureTime frameDescription
Clinician's Severity Rating (CSR) Scale of Anxiety Disorders Interview Schedule for DSM-IV (ADIS-IV)Pretreatment to posttreatment (12 weeks) and 6-month Follow-UpThe CSR is a severity rating scale ranging from 0-8. Scores of 4 or greater represent clinically significant symptoms, whereas scores lower than 4 indicate subclinical symptoms. Lower scores represent improved outcome. This measure was used to evaluate change from baseline in the severity of GAD symptoms as assessed by the ADIS-IV, a semi-structured clinical interview for Axis I disorders.

Secondary

MeasureTime frameDescription
Intolerance of Uncertainty Scale (IUS)Pretreatment to posttreatment (12 weeks) and 6-month Follow-UpThe IUS is a self-report questionnaire assessing intolerance of uncertainty, or the tendency to view uncertainty and its consequences as negative. Scores range from 27 to 135, with higher scores representing greater intolerance of uncertainty. The IUS was used to assess change from baseline in self-reported intolerance of uncertainty.
Penn State Worry Questionnaire (PSWQ)Pretreatment to posttreatment (12 weeks) and 6-month Follow-UpThe PSWQ is a self-report questionnaire assessing excessive and uncontrollable worry. Scores range from 16 to 80, with greater scores indicating greater worry. The PSWQ was used to evaluate change from baseline in self-reported worry.
Worry and Anxiety Questionnaire (WAQ)Pretreatment to posttreatment (12 weeks) and 6-month Follow-UpThe WAQ is a questionnaire assessing self-reported symptoms of GAD. Scores range from 0 to 56, with higher scores indicating greater severity of self-rated GAD symptoms. The measure was used to assess change from baseline in self-reported GAD symptoms (WAQ).
Beck Anxiety Inventory (BAI)Pretreatment to posttreatment (12 weeks) and 6-month Follow-UpThe BAI is a self-report questionnaire assessing affective, cognitive, and somatic anxiety over the preceding week. Scores range from 0 to 63, with greater scores representing greater self-reported anxiety. The BAI was used to evaluate change from baseline in self-reported anxiety.
Beck Depression Inventory, 2nd Edition (BDI-II)Pretreatment to posttreatment (12 weeks) and 6-month Follow-UpThe BDI-II is a self-report questionnaire assessing a variety of depressive symptoms, including low mood, anhedonia, and worthlessness. Scores range from 0 to 63, with greater scores indicating greater depressive symptoms. The BDI-II was used to evaluate change from baseline in self-reported depressive symptoms.
GAD Safety Behaviours Questionnaire (GAD-SBQ)Pretreatment to posttreatment (12 weeks) and 6-month Follow-UpThe GAD-SBQ is a self-report questionnaire assessing the tendency to use safety behaviours to cope with anxiety, such as reassurance-seeking and overpreparation. Scores range from 18 to 90, with greater scores indicating greater use of safety behaviours. The GA-SBQ was used to evaluate change from baseline in self-reported safety behaviours.

Countries

Canada

Participant flow

Recruitment details

The study was approved by Human Research Ethics Committees of Concordia University and the Hôpital du Sacré-Coeur de Montréal. Participants self-referred to the Hôpital du Sacré-Coeur de Montréal anxiety clinic via advertisements placed in a local newspaper. Recruitment occurred between April 2013 to March 2014.

Participants by arm

ArmCount
Cognitive-Behavioural Treatment
12 weekly sessions of individual cognitive-behavioural treatment (CBT) targeting intolerance of uncertainty via behavioural experiments
7
Total7

Baseline characteristics

CharacteristicCognitive-Behavioural Treatment
Age, Categorical
<=18 years
0 Participants
Age, Categorical
>=65 years
0 Participants
Age, Categorical
Between 18 and 65 years
7 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
0 Participants
Race (NIH/OMB)
Black or African American
0 Participants
Race (NIH/OMB)
More than one race
0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
White
7 Participants
Region of Enrollment
Canada
7 participants
Sex: Female, Male
Female
5 Participants
Sex: Female, Male
Male
2 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
— / —
other
Total, other adverse events
0 / 7
serious
Total, serious adverse events
0 / 7

Outcome results

Primary

Clinician's Severity Rating (CSR) Scale of Anxiety Disorders Interview Schedule for DSM-IV (ADIS-IV)

The CSR is a severity rating scale ranging from 0-8. Scores of 4 or greater represent clinically significant symptoms, whereas scores lower than 4 indicate subclinical symptoms. Lower scores represent improved outcome. This measure was used to evaluate change from baseline in the severity of GAD symptoms as assessed by the ADIS-IV, a semi-structured clinical interview for Axis I disorders.

Time frame: Pretreatment to posttreatment (12 weeks) and 6-month Follow-Up

ArmMeasureGroupValue (MEAN)Dispersion
Cognitive-Behavioural TreatmentClinician's Severity Rating (CSR) Scale of Anxiety Disorders Interview Schedule for DSM-IV (ADIS-IV)Pretreatment ADIS-IV5.5 units on a scaleStandard Deviation 0.82
Cognitive-Behavioural TreatmentClinician's Severity Rating (CSR) Scale of Anxiety Disorders Interview Schedule for DSM-IV (ADIS-IV)Posttreatment ADIS-IV3.14 units on a scaleStandard Deviation 1.03
Cognitive-Behavioural TreatmentClinician's Severity Rating (CSR) Scale of Anxiety Disorders Interview Schedule for DSM-IV (ADIS-IV)6-month follow-up ADIS-IV2.43 units on a scaleStandard Deviation 1.9
Comparison: Pre-posttreatment effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from pretreatment to posttreatmentCohen's d effect size
Comparison: Pretreatment to 6-month follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from pretreatment to 6-month follow-upCohen's d effect size
Comparison: Posttreatment to 6-month follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from posttreatment to 6-month follow-upCohen's d effect size
Secondary

Beck Anxiety Inventory (BAI)

The BAI is a self-report questionnaire assessing affective, cognitive, and somatic anxiety over the preceding week. Scores range from 0 to 63, with greater scores representing greater self-reported anxiety. The BAI was used to evaluate change from baseline in self-reported anxiety.

Time frame: Pretreatment to posttreatment (12 weeks) and 6-month Follow-Up

ArmMeasureGroupValue (MEAN)Dispersion
Cognitive-Behavioural TreatmentBeck Anxiety Inventory (BAI)Pretreatment BAI23.71 units on a scaleStandard Deviation 10.47
Cognitive-Behavioural TreatmentBeck Anxiety Inventory (BAI)Posttreatment BAI9.86 units on a scaleStandard Deviation 10.56
Cognitive-Behavioural TreatmentBeck Anxiety Inventory (BAI)6-month follow-up BAI12.57 units on a scaleStandard Deviation 12.12
Comparison: Pre-posttreatment effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from pretreatment to posttreatmentCohen's d effect size
Comparison: Pretreatment to 6-month follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from pretreatment to 6-month follow-upCohen's d effect size
Comparison: Posttreatment to 6-month follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from posttreatment to 6-month follow-upCohen's d effect size
Secondary

Beck Depression Inventory, 2nd Edition (BDI-II)

The BDI-II is a self-report questionnaire assessing a variety of depressive symptoms, including low mood, anhedonia, and worthlessness. Scores range from 0 to 63, with greater scores indicating greater depressive symptoms. The BDI-II was used to evaluate change from baseline in self-reported depressive symptoms.

Time frame: Pretreatment to posttreatment (12 weeks) and 6-month Follow-Up

ArmMeasureGroupValue (MEAN)Dispersion
Cognitive-Behavioural TreatmentBeck Depression Inventory, 2nd Edition (BDI-II)6-month follow-up BDI-II5.57 units on a scaleStandard Deviation 5.16
Cognitive-Behavioural TreatmentBeck Depression Inventory, 2nd Edition (BDI-II)Pretreatment BDI-II14.71 units on a scaleStandard Deviation 4.39
Cognitive-Behavioural TreatmentBeck Depression Inventory, 2nd Edition (BDI-II)Posttreatment BDI-II4.00 units on a scaleStandard Deviation 5.69
Comparison: Pre-posttreatment effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from pretreatment to posttreatmentCohen's d effect size
Comparison: Pretreatment to 6-month follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from pretreatment to 6-month follow-upCohen's d effect size
Comparison: Posttreatment to 6-month follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from posttreatment to 6-month follow-upCohen's d effect size
Secondary

GAD Safety Behaviours Questionnaire (GAD-SBQ)

The GAD-SBQ is a self-report questionnaire assessing the tendency to use safety behaviours to cope with anxiety, such as reassurance-seeking and overpreparation. Scores range from 18 to 90, with greater scores indicating greater use of safety behaviours. The GA-SBQ was used to evaluate change from baseline in self-reported safety behaviours.

Time frame: Pretreatment to posttreatment (12 weeks) and 6-month Follow-Up

ArmMeasureGroupValue (MEAN)Dispersion
Cognitive-Behavioural TreatmentGAD Safety Behaviours Questionnaire (GAD-SBQ)Pretreatment GAD-SBQ47.00 units on a scaleStandard Deviation 9.95
Cognitive-Behavioural TreatmentGAD Safety Behaviours Questionnaire (GAD-SBQ)Posttreatment GAD-SBQ32.71 units on a scaleStandard Deviation 5.53
Cognitive-Behavioural TreatmentGAD Safety Behaviours Questionnaire (GAD-SBQ)6-month follow-up GAD-SBQ36.14 units on a scaleStandard Deviation 5.11
Comparison: Pre-posttreatment effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from pretreatment to posttreatmentCohen's d effect size
Comparison: Pretreatment to 6-month follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from pretreatment to 6-month follow-upCohen's d effect size
Comparison: Posttreatment to 6-month follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from posttreatment to 6-month follow-upCohen's d effect size
Secondary

Intolerance of Uncertainty Scale (IUS)

The IUS is a self-report questionnaire assessing intolerance of uncertainty, or the tendency to view uncertainty and its consequences as negative. Scores range from 27 to 135, with higher scores representing greater intolerance of uncertainty. The IUS was used to assess change from baseline in self-reported intolerance of uncertainty.

Time frame: Pretreatment to posttreatment (12 weeks) and 6-month Follow-Up

ArmMeasureGroupValue (MEAN)Dispersion
Cognitive-Behavioural TreatmentIntolerance of Uncertainty Scale (IUS)Pretreatment IUS85.71 units on a scaleStandard Deviation 14.71
Cognitive-Behavioural TreatmentIntolerance of Uncertainty Scale (IUS)Posttreatment IUS55.00 units on a scaleStandard Deviation 15.55
Cognitive-Behavioural TreatmentIntolerance of Uncertainty Scale (IUS)6-month follow-up IUS54.29 units on a scaleStandard Deviation 12.3
Comparison: Pre-posttreatment follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from pretreatment to posttreatment follow-upCohen's d effect size
Comparison: Pretreatment to 6-month follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from pretreatment to 6-month follow-upCohen's d effect size
Comparison: Posttreatment to 6-month follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from posttreatment to 6-month follow-upCohen's d effect size
Secondary

Penn State Worry Questionnaire (PSWQ)

The PSWQ is a self-report questionnaire assessing excessive and uncontrollable worry. Scores range from 16 to 80, with greater scores indicating greater worry. The PSWQ was used to evaluate change from baseline in self-reported worry.

Time frame: Pretreatment to posttreatment (12 weeks) and 6-month Follow-Up

ArmMeasureGroupValue (MEAN)Dispersion
Cognitive-Behavioural TreatmentPenn State Worry Questionnaire (PSWQ)Pretreatment PSWQ61.57 units on a scaleStandard Deviation 6
Cognitive-Behavioural TreatmentPenn State Worry Questionnaire (PSWQ)Posttreatment PSWQ50.00 units on a scaleStandard Deviation 8.25
Cognitive-Behavioural TreatmentPenn State Worry Questionnaire (PSWQ)6-month follow-up PSWQ51.14 units on a scaleStandard Deviation 6.15
Comparison: Pre-posttreatment effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from pretreatment to posttreatmentCohen's d effect size
Comparison: Pretreatment to 6-month follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from pretreatment to 6-month follow-upCohen's d effect size
Comparison: Posttreatment to 6-month follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from posttreatment to 6-month follow-upCohen's d effect size
Secondary

Worry and Anxiety Questionnaire (WAQ)

The WAQ is a questionnaire assessing self-reported symptoms of GAD. Scores range from 0 to 56, with higher scores indicating greater severity of self-rated GAD symptoms. The measure was used to assess change from baseline in self-reported GAD symptoms (WAQ).

Time frame: Pretreatment to posttreatment (12 weeks) and 6-month Follow-Up

ArmMeasureGroupValue (MEAN)Dispersion
Cognitive-Behavioural TreatmentWorry and Anxiety Questionnaire (WAQ)Posttreatment WAQ24.36 units on a scaleStandard Deviation 9.06
Cognitive-Behavioural TreatmentWorry and Anxiety Questionnaire (WAQ)Pretreatment WAQ38.36 units on a scaleStandard Deviation 5.25
Cognitive-Behavioural TreatmentWorry and Anxiety Questionnaire (WAQ)6-month follow-up WAQ25.43 units on a scaleStandard Deviation 6.42
Comparison: Pre-posttreatment effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from pretreatment to posttreatmentCohen's d effect size
Comparison: Pretreatment to 6-month follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from pretreatment to 6-month follow-upCohen's d effect size
Comparison: Posttreatment to 6-month follow-up effect size estimation using Cohen's d: a calculation of the relative magnitude of the effect from posttreatment to 6-month follow-upCohen's d effect size

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026