Anti-phobic and Safety Behaviors in the Treatment of Acrophobia

Study Overview
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Brief Summary
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This study tests whether a single session of exposure therapy may be enhanced by the addition of anti-phobic actions beyond the mere fading of safety behaviors. A total of 100 acrophobic participants will be randomly assigned to receive standard exposure therapy (EXP), exposure therapy with safety behavior fading (EXP + SBF), exposure with safety behavior fading and anti-phobic actions (EXP + SBF + AA), or to a wait-list control group (WL).

Detailed Description
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This study tests whether a single session of exposure therapy may be enhanced by the addition of one of two augmentation strategies, including engagement in anti-phobic actions and fading of safety behaviors. Because utilization of safety behaviors is functionally precluded by anti-phobic action, the present study design will both replicate and extend prior research by addressing whether anti-phobic actions enhance exposure therapy beyond the mere fading of safety behaviors. A total of 100 individuals between the ages of 18 and 65 meeting DSM-IV criteria for acrophobia (fear of heights) will be randomly assigned to one of four conditions including (1) standard exposure therapy, (2) exposure therapy with safety behavior fading, (3) exposure therapy with safety behavior fading and anti-phobic actions, and (4) a wait-list control condition. All participants will complete an online prescreen and face-to-face screening assessment to determine eligibility and pre-treatment symptom severity. Participants will also complete assessments at post-treatment and 1-month follow-up assessments. Subjective fear during two behavioral approach tests (in the treatment and generalization context, respectively) conducted at pre-treatment, post-treatment, and 1-month follow-up assessments will serve as the primary measure of treatment outcome. Additionally, a battery of self-report questionnaires will be completed at pre-treatment, during treatment, at post-treatment, and at a 1-month follow-up assessment.

Official Title
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Anti-phobic and Safety Behaviors in the Treatment of Acrophobia

Conditions
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Specific Phobia

Intervention / Treatment
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* Behavioral: EXP
* Behavioral: EXP + SBF
* Behavioral: EXP + SBF + AA


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18 to 65. Fluent in English (written and spoken). This is required because assessment instruments are validated only in English. Meet DSM-IV criteria for specific phobia, natural environment type, with acrophobic concerns, based on the Composite International Diagnostic Interview (CIDI-Auto; World Health Organization, 1997). Report moderate fear or avoidance (i.e., a score of 30 or higher) on a modified version of the Acrophobia Questionnaire (AQ; Cohen, 1977). Exhibit at least moderate fear (i.e., a fear score of 50 or higher, where 0 = no fear and 100 = extreme fear) during two behavioral approach tests (BATs) consisting of ascending two moderately challenging flights of stairs. Exclusion Criteria: 1. Medical condition(s) which may prevent safely climbing or descending stairs or walking for more than 15 minutes at a time (It will be necessary to walk to different sites for the behavioral approach tests).

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: EXP + SBF + AA<br>Exposure therapy (EXP) with safety behavior fading (SBF) and anti-phobic action (AA) | Behavioral: EXP<br>* Participants will receive one-session exposure therapy consisting of six-6 minute trials of exposure to heights, involving ascending a 9-landing flight of outdoor stairs. Participants will be asked to ascend, accompanied by the therapist who will provide verbal encouragement throughout supporting efforts at exposure. An instructional set will be provided prior to treatment presenting the rationale for exposure as an effective means of reducing pathological fear.<br>* Other names: Standard Therapist-Guided In Vivo Exposure Therapy (EXP);Behavioral: EXP + SBF<br>* Participants will receive one-session exposure therapy consisting of six-6 minute trials of exposure to heights, involving ascending a 9-landing flight of outdoor stairs. Participants will be asked to ascend, accompanied by the therapist who will provide verbal encouragement supporting efforts at exposure. An instructional set will be provided prior to treatment explaining how safety behaviors serve to maintain fear, and how their elimination may enhance fear reduction. Additionally, the therapist will identify safety behaviors and prompt participants to reduce their utilization of them during treatment.<br>* Other names: Exposure Therapy with Safety Behavior Fading (EXP + SBF);Behavioral: EXP + SBF + AA<br>* Participants will receive one-session exposure therapy consisting of six-6 minute trials of exposure to heights, involving ascending a 9-landing flight of outdoor stairs. Participants will be asked to ascend, accompanied by the therapist who will provide verbal encouragement supporting efforts at exposure. An instructional set will be provided explaining the rationale for eliminating safety behaviors, and how engagement in anti-phobic actions may enhance fear reduction. Additionally, the therapist will identify safety behaviors and prompt participants to reduce their utilization of them during treatment, and will instruct participants to enact a series of progressively challenging anti-phobic actions which oppose the prototypical fear response.<br>* Other names: Exposure with Safety Behavior Fading and Anti-Phobic Actions;|
| Active Comparator: EXP + SBF<br>Exposure therapy (EXP) with safety behavior fading (SBF) | Behavioral: EXP<br>* Participants will receive one-session exposure therapy consisting of six-6 minute trials of exposure to heights, involving ascending a 9-landing flight of outdoor stairs. Participants will be asked to ascend, accompanied by the therapist who will provide verbal encouragement throughout supporting efforts at exposure. An instructional set will be provided prior to treatment presenting the rationale for exposure as an effective means of reducing pathological fear.<br>* Other names: Standard Therapist-Guided In Vivo Exposure Therapy (EXP);Behavioral: EXP + SBF<br>* Participants will receive one-session exposure therapy consisting of six-6 minute trials of exposure to heights, involving ascending a 9-landing flight of outdoor stairs. Participants will be asked to ascend, accompanied by the therapist who will provide verbal encouragement supporting efforts at exposure. An instructional set will be provided prior to treatment explaining how safety behaviors serve to maintain fear, and how their elimination may enhance fear reduction. Additionally, the therapist will identify safety behaviors and prompt participants to reduce their utilization of them during treatment.<br>* Other names: Exposure Therapy with Safety Behavior Fading (EXP + SBF);|
| Active Comparator: EXP<br>Standard therapist-guided in vivo exposure therapy (EXP) | Behavioral: EXP<br>* Participants will receive one-session exposure therapy consisting of six-6 minute trials of exposure to heights, involving ascending a 9-landing flight of outdoor stairs. Participants will be asked to ascend, accompanied by the therapist who will provide verbal encouragement throughout supporting efforts at exposure. An instructional set will be provided prior to treatment presenting the rationale for exposure as an effective means of reducing pathological fear.<br>* Other names: Standard Therapist-Guided In Vivo Exposure Therapy (EXP);|
| No Intervention: Wait-list control<br>Subjects assigned to this arm will undergo assessments at Weeks 0, Week 1, and Week 5, but will not receive any interventions. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peak subjective fear (0 - 100) upon exposure to heights in the generalization context. | Peak subjective fear ratings (0 - 100). | Pre-treatment (1 week before treatment), treatment (1 week after pre-treatment), post-treatment (immediately following treatment), and follow-up (1 month after treatment). | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Acrophobia Questionnaire - Modified (Cohen, 1977; Wolitzky & Telch, 2009) | 20-item Likert-type scale assessing acrophobic symptoms | Pre-treatment (1 week before treatment), treatment (1 week after pre-treatment), post-treatment (immediately following treatment), and follow-up (1 month after treatment). | 
| Height estimation task | Perceptual task requiring estimation of height from the top of a flight of stairs | Pre-treatment (1 week before treatment), treatment (1 week after pre-treatment), post-treatment (immediately following treatment), and follow-up (1 month after treatment). | 
| Heart rate | Heart rate reactivity assessed using a Polar Heart Rate Monitor. | Pre-treatment (1 week before treatment), treatment (1 week after pre-treatment), post-treatment (immediately following treatment), and follow-up (1 month after treatment). | 
| Treatment Process Questionnaire | Self-efficacy, anticipated anxiety, anticipated danger, and utilization of safety behaviors assessed via self-report. | Treatment (1 week following pre-treatment assessment) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Exposure therapy, Specific phobia, Fear of heights, Acrophobia, Safety behavior fading, Anti-phobic Actions