Intolerance-of-uncertainty therapy for GAD

1. Introduction

Version followed: the six-module CBT-IU protocol of Robichaud, Koerner & Dugas (2019, 2nd ed., Cognitive Behavioral Treatment for Generalized Anxiety Disorder: From Science to Practice), as summarised by Dunkley & Robichaud (2022) and as delivered in Bouchard et al. (2022). The single-component "behavioural experiments for IU" variant (Hebert & Dugas, 2019; trial NCT02552108, "A Single-Component CBT for GAD") is given as an alternative route. The book itself is not drawn on; step-level detail beyond the summaries is marked [uncertain].

• What it is: a manualised, modular CBT for generalised anxiety disorder (GAD), developed by Michel Dugas, Robert Ladouceur and colleagues at Laval University (Quebec) from the 1990s and later refined with Melisa Robichaud and Naomi Koerner. [source: Routledge book page; Dunkley & Robichaud 2022]
• Core idea of change: intolerance of uncertainty (IU) is a higher-order process that keeps the worry cycle going. Negative beliefs about uncertainty (for example, that it is unfair, dangerous or that one cannot function when unsure) make everyday uncertainty hard to bear. Worry is then a mental attempt to plan away that uncertainty. Change comes from building more balanced beliefs about uncertainty and its consequences, so the client can tolerate not knowing without worrying, checking, seeking reassurance or avoiding. [source: Dunkley & Robichaud 2022 chapter summary]
• Model in the experiments variant: triggers are ambiguous, novel or unpredictable situations. Catastrophic beliefs about uncertainty are the central component and lead to anxiety, worry and safety behaviours such as avoidance, information-gathering and reassurance-seeking. These behaviours stop the person from ever learning that uncertainty is tolerable. [source: Psychology Tools article summarising Hebert & Dugas 2019]
• Founder's framing for clients: Dugas described IU as an "allergy" to uncertainty, where a very small amount produces a strong reaction. [source: Dugas CPA 2000 workshop summary]

2. Framework

Format and dose (version followed). In Bouchard et al. (2022), treatment ran for 15 weekly 60-minute individual sessions in six modules. Therapists had to deliver all six modules in order and could not add material, but could vary the pace by one or two sessions. Written home exercises were set between every session. [source: Bouchard et al. 2022]

[source: Bouchard et al. 2022 for structure and session counts; Dunkley & Robichaud 2022 and Routledge book description for module contents]

Other versions.

• First edition (Dugas & Robichaud, 2007): the order is usually given as psychoeducation and worry awareness, uncertainty recognition and behavioural exposure, re-evaluation of the usefulness of worry, problem-solving training, imaginal (cognitive) exposure, then relapse prevention. [uncertain: first edition] In this version, cognitive exposure to core fears, problem-solving and re-evaluation of worry beliefs were the named components. [source: Dugas CPA 2000 workshop summary]
• Earlier trials: Ladouceur et al. (2000) delivered individual treatment and Dugas et al. (2003) delivered it in groups. These are commonly cited as about 16 individual weekly sessions and 14 weekly two-hour group sessions respectively. [uncertain: papers; counts not verified]
• Single-component experiments variant: 12 weekly individual sessions that work only through behavioural experiments targeting beliefs about uncertainty. It is presented as narrower and deeper than earlier CBT-IU and suggested for clients who do not remit with standard CBT-IU. [source: Psychology Tools article on Hebert & Dugas 2019] Session-by-session content of the RCT protocol (NCT02552108) is not drawn on. [uncertain]

Criteria for moving between modules. The manual is written by module rather than session, so pacing follows the client within a set range. [source: Bouchard et al. 2022] Dunkley & Robichaud (2022) say each module can be applied flexibly to fit the client. Explicit criteria for moving on are not given in the sources. Practical criteria [synthesis]:

• Leave Module 1 when the client can catch worry episodes in real time and can say whether a worry is about a current problem or a hypothetical situation.
• Leave Module 2 when the client can state at least one cost of worry and their belief in worry's usefulness has dropped on a 0–100 rating.
• Leave Module 3 when the client is running experiments without prompting and belief ratings about uncertainty are falling.
• Leave Module 4 when the client has worked one real problem through all the steps.
• Leave Module 5 when anxiety to the scenario has clearly reduced across exposures and the client stops neutralising.

Assessment instruments used in this tradition (described, not reproduced): the Intolerance of Uncertainty Scale (IUS), Penn State Worry Questionnaire (PSWQ) and Worry and Anxiety Questionnaire (WAQ). They can be given as homework at intervals to track progress. [source: Dugas CPA 2000 workshop summary] The IUS can also help identify which beliefs to test. [source: Psychology Tools article] Questionnaires and monitoring forms appear in the 2019 book. [source: Routledge book page]

3. Guiding principles

• Target uncertainty, not the content of worries. Work on how the client relates to not knowing, rather than disputing each feared outcome one by one. [source: Dunkley & Robichaud 2022]
• The goal is tolerance, not certainty. Success means the client acts well while still unsure, not that they feel sure. [source: Dunkley & Robichaud 2022]
• Worry is an attempt to reduce uncertainty and works as a safety behaviour. Treat worry, checking, reassurance-seeking and avoidance as one family of behaviours to reduce. [source: Psychology Tools article; Chigwedere & Moran 2022 describe worry as a safety behaviour in their adaptation]
• Change beliefs directly through experience. Prefer experiments that test a belief about uncertainty over repeated exposure alone, because indirect change may leave the belief room to persist. [source: Psychology Tools article on Hebert & Dugas 2019]
• Collaborate. Design experiments with the client, never for them. [source: Psychology Tools article]
• Distinguish normal from extreme intolerance. Everyone prefers certainty. The target is the extreme negative beliefs, so don't aim to make the client indifferent to outcomes. [source: Psychology Tools article]
• Match the tool to the type of worry. Use problem-solving for worries about real, current problems and written exposure for worries about remote or hypothetical situations. [source: Dunkley & Robichaud 2022 lists both modules; the explicit two-type rule is uncertain]
• Approach problems as challenges. Help the client see problems as a normal part of life to be tackled, not threats to be worried about. [source: Routledge book description]
• Deliver modules in order, flex the pace. Keep the sequence and adjust the number of sessions per module. [source: Bouchard et al. 2022]
• Practice between sessions drives change. Set a written home exercise every session and review it first next time. [source: Bouchard et al. 2022, where fidelity ratings checked this]
• Measure. Repeat IU and worry measures through treatment to guide decisions. [source: Dugas CPA 2000 workshop summary]
• Don't become a source of certainty. Avoid answering the client's "what if" questions with reassurance. [synthesis]

4. Intervention inventory

Module-level contents are sourced from Dunkley & Robichaud (2022), Bouchard et al. (2022) and the Routledge book description. Step-by-step procedures below are written in my own words. Where the sources gave no procedure, the steps follow the standard CBT-IU sequence as commonly described in the treatment literature and are marked [uncertain]. All example language is illustrative and is not quoted from the manual.

4.1 Psychoeducation about GAD and the IU model (Module 1)

• Purpose: give the client a shared, plausible model of their problem that makes the later exercises make sense. Use it in session 1. [source: Bouchard et al. 2022; Dunkley & Robichaud 2022]
• Steps:
  1. Separate worry (thoughts about what might go wrong) from anxiety (body and feeling state), and show how each feeds the other. [uncertain]
  2. Normalise. Everyone worries and everyone prefers certainty. In GAD the difference is the amount of worry and how strongly the person reacts to not knowing. [source: Psychology Tools article]
  3. Introduce IU with the "allergy" image: a tiny dose of uncertainty triggers a big reaction. [source: Dugas CPA 2000]
  4. Draw the cycle from the client's own recent example: uncertain trigger, then beliefs about uncertainty, then worry, anxiety and safety behaviours, then no new learning. [source: Psychology Tools article on the Hebert & Dugas 2019 model]
  5. Point out the paradox Dugas described. Clients often know a feared event is very unlikely yet keep worrying, which shows the driver is the uncertainty rather than the probability. [source: Dugas CPA 2000 plane-crash example]
  6. Preview the modules and the role of home practice.
• Example language (illustrative): "You already know the chance of this happening is tiny. The worry isn't about the odds. It's about not being able to rule it out completely. That's what we'll work on."
• Watch for: a client who hears "IU" as a fixed trait. Frame it as a set of beliefs that can be tested. It is working when the client starts spotting uncertainty in their own examples. [synthesis]

4.2 Shared case formulation and goal setting (Module 1)

• Purpose: link the general model to this client's triggers, beliefs and behaviours, and set end-of-treatment goals. [source: Bouchard et al. 2022 lists a shared case formulation in session 1; goal-setting in session 1 is described in the Chigwedere & Moran 2022 adaptation]
• Steps:
  1. Take two or three recent worry episodes and map each onto the cycle.
  2. Note the client's typical safety behaviours and any beliefs about uncertainty they voice.
  3. Agree concrete goals stated as behaviour, for example "make decisions at work without double-checking with my manager". [synthesis]
  4. Record baseline scores on IUS and PSWQ. [source: Dugas CPA 2000]
• Example language (illustrative): "In the last week, when you felt the worry spin up, what was the thing you didn't know?"
• Watch for: formulations that stay at the level of worry topics (health, money, family). Push down to the shared element, which is not knowing. [synthesis]

4.3 Worry awareness training and monitoring (Module 1)

• Purpose: help the client notice worry as it happens rather than after an hour of it, and collect data for later modules. [source: Dunkley & Robichaud 2022 list "worry awareness" training in Module 1]
• Steps:
  1. Give a simple diary. Clients record at set times of day what they were worrying about and rate their anxiety. [uncertain: exact format in the manual] A published adaptation used columns for cue event, feelings, current uncertainty and hypothetical worry. [source: Chigwedere & Moran 2022]
  2. Review the diary every session, looking for themes, triggers and the moment the worry started.
  3. Teach the client to catch the shift from noticing a trigger to starting the worry. [synthesis]
• Example language (illustrative): "This week, just notice and write. You don't need to stop the worry yet, only catch it."
• Watch for: sparse diaries, which usually reflect low awareness or a belief that writing worries makes them worse (see Section 5). It is working when entries become specific and are recorded close to the episode. [synthesis]

4.4 Classifying worries: current problems versus hypothetical situations (Module 1)

• Purpose: decide which later tool each worry needs. Worries about real, current problems go to problem-solving (4.11–4.12). Worries about remote or imagined situations go to written exposure (4.13). [uncertain: this rule is drawn from the first-edition literature; the 2019 module list in Dunkley & Robichaud 2022 is consistent with it but the book is not drawn on]
• Steps:
  1. For each diary entry, ask whether the problem exists now and whether the client can act on it now.
  2. If yes to both, label it a current problem. If it is about something that has not happened and may never happen, label it hypothetical.
  3. Mixed worries can be split: the actionable part goes to problem-solving and the "what if" tail goes to exposure. [synthesis]
• Example language (illustrative): "Is this something happening right now that you could do something about this week, or is it a 'what if' about the future?"
• Watch for: clients who label everything "current" so they can keep planning. It is working when the client sorts worries quickly and the two lists look different. [synthesis]

4.5 Re-evaluating the usefulness of worry (Module 2)

• Purpose: weaken positive beliefs about worry that keep the client from wanting to let it go. Use it early, in session 2 in the version followed. [source: Bouchard et al. 2022; Dunkley & Robichaud 2022]
• Steps:
  1. Identify the client's positive beliefs about worry. The Dugas group's questionnaire tradition groups them roughly as follows: worry helps solve problems, worry motivates, worry protects against negative emotion by preparing for the worst, worry itself can prevent bad outcomes, and worry shows one is a caring or responsible person. [uncertain: categories from the wider literature]
  2. Take one belief at a time. Rate conviction from 0 to 100.
  3. Examine it with Socratic questions. What is the evidence that worry did this? Did the bad events that happened come with less distress because of prior worry? Could the same benefit come from something other than worry? [uncertain: specific questions]
  4. Where possible, turn it into a test, for example comparing a day of planned problem-solving with a day of worrying about the same issue. [synthesis]
  5. Re-rate conviction and write down a balanced alternative belief.
• Example language (illustrative): "You've said worrying keeps your kids safe. Let's look at that. On the days you worried less, did anything happen to them?"
• Watch for: a debate. Stay curious and let the client weigh the evidence. A client who says worry is "just who I am" may hold the caring-person belief, so address it directly. It is working when conviction ratings drop and the client becomes willing to try reducing worry. [synthesis]

4.6 Identifying negative beliefs about uncertainty (Module 3)

• Purpose: find the specific beliefs that experiments will test. [source: Dunkley & Robichaud 2022; Psychology Tools article]
• Steps:
  1. Explain that a preference for certainty is normal, while beliefs that uncertainty is catastrophic are the target. [source: Psychology Tools article]
  2. Elicit beliefs from diary examples. Hebert & Dugas group them into two families: (a) uncertainty has negative implications for oneself and one's behaviour, for example that one cannot function or will make mistakes when unsure; and (b) uncertainty is unfair and spoils everything. [source: Psychology Tools article]
  3. Use IUS items the client endorsed strongly as prompts, without handing them the scale wording as a belief to adopt. [source: Psychology Tools article notes the IUS can be used this way]
  4. Write each belief in the client's own words and rate conviction from 0 to 100.
• Example language (illustrative): "When you don't know how the meeting will go, what do you believe that says about you or about what will happen?"
• Watch for: beliefs stated as feared outcomes ("the meeting will go badly"). Reframe them as beliefs about uncertainty ("if I'm not sure, I'll fail"). [synthesis]

4.7 Identifying safety behaviours (Module 3)

• Purpose: list the behaviours the client uses to reduce or escape uncertainty, because these are what experiments will drop. [source: Dunkley & Robichaud 2022; Psychology Tools article]
• Steps:
  1. Explain that these behaviours bring short-term relief and long-term maintenance of the problem.
  2. Build a list from the diary. The named examples are avoidance, information-gathering and reassurance-seeking. [source: Psychology Tools article] Common further forms include repeated checking, over-preparing, procrastinating, refusing to delegate and distracting oneself. [uncertain: these extra examples are from the wider literature]
  3. For each behaviour, note what the client believes would happen without it.
• Example language (illustrative): "What do you do to get rid of not knowing? Some people check, some ask others, some avoid deciding at all."
• Watch for: hidden or mental safety behaviours such as reviewing a conversation in one's head or silently reassuring oneself. Ask about these specifically. [synthesis]

4.8 Behavioural experiments targeting beliefs about uncertainty (Module 3; the whole treatment in the single-component variant)

• Purpose: test negative beliefs about uncertainty by acting under uncertainty, usually without the usual safety behaviour, and seeing what happens. This is the core intervention of the Hebert & Dugas (2019) approach and of Module 3 in the 2019 protocol. [source: Psychology Tools article; Dunkley & Robichaud 2022; Routledge book description]
• Steps: [source for steps 1–4: Psychology Tools article on Hebert & Dugas 2019]
  1. Name the belief and rate it. Choose one belief from 4.6 and record the conviction rating.
  2. Design the experiment together. Choose a specific situation and drop or reduce a safety behaviour from 4.7. Agree on when and how often, and write down what the client predicts will happen and how badly they expect to cope. [prediction and coping fields: uncertain, standard experiment format]
  3. Run it and record the result. Note what actually happened, whether it was positive, negative or neutral, and if negative, how well the client coped. [result categories: uncertain]
  4. Reflect and re-rate. Ask what the result says about the belief, re-rate conviction, and plan the next experiment.
• Worked example: for the belief that not knowing is unbearable and reassurance is necessary, compare three days of seeking reassurance as usual with three days of refraining, and compare anxiety and outcomes. [source: Psychology Tools article]
• Example experiments [synthesis, drawn from the safety-behaviour list]: order an unfamiliar dish without reading reviews; send an email without re-reading it more than once; let a colleague complete a task without checking it; book a film without researching it; make a small purchase without comparing prices.
• Example language (illustrative): "Your prediction is that if you send it without checking, you'll make a mistake and won't cope. Let's find out. What exactly will you do, and what would count as 'not coping'?"
• Watch for: experiments done with a hidden safety behaviour still in place, which leaves the belief untested. Also watch for experiments that are too big too soon. Start where the client is willing. It is working when outcomes are mostly neutral or manageable, conviction ratings fall, and the client starts suggesting experiments. [synthesis]

4.9 Ongoing and generalising experiments (Module 3 into Module 6)

• Purpose: move from set-piece experiments to a habit of choosing uncertainty in daily life. [source: Psychology Tools article, which describes planning ongoing experiments such as deliberately choosing uncertain paths]
• Steps:
  1. Review the experiments so far and compare old and new ways of behaving.
  2. Agree a standing practice: when a choice comes up between a certain and an uncertain option of similar cost, pick the uncertain one. [synthesis, built on the source's "choosing uncertain paths"]
  3. Extend experiments to new areas of life (work, relationships, health), not only the first area worked on. [synthesis]
• Example language (illustrative): "This week, any time you notice you're about to look something up just to feel sure, treat that as a chance to run a mini-experiment."
• Watch for: experiments that become a new ritual done to feel safe. It is working when the client acts under uncertainty without planning it as an exercise. [synthesis]

4.10 Setting and reviewing home exercises (every module)

• Purpose: make between-session practice the engine of change. In the version followed, written home exercises are provided in the manual for every session, and fidelity checks look at whether the therapist reviews the last exercise and plans the next one. [source: Bouchard et al. 2022]
• Steps:
  1. Open each session by reviewing the exercise: what was done, what happened, what was learned.
  2. Close each session by agreeing the next exercise, including when, where and how often, and naming likely obstacles.
• Example language (illustrative): "Before we start anything new, tell me how the experiments went. What surprised you?"
• Watch for: see non-adherence in Section 5. [synthesis]

4.11 Problem orientation training (Module 4)

• Purpose: change the client's attitude to problems before teaching skills. Clients high in IU tend to see problems as threats, doubt their ability and delay acting. The goal is to see problems as normal challenges to approach. [source: Routledge book description ("reframe worry-provoking problems as challenges rather than threats"); Dunkley & Robichaud 2022 list "reorienting how the client approaches problems"]
• Steps: [uncertain: specific exercises]
  1. Discuss how the client usually reacts to a problem, including avoidance, waiting for the perfect solution, or doubting their competence.
  2. Present problems as a normal, unavoidable part of life.
  3. Teach recognising problems early, using rising anxiety or worry as a cue that a problem needs attention. [uncertain]
  4. Practise reframing a current problem as a challenge, for example by naming something that could be gained or learned. [uncertain]
  5. Link to IU. Every real solution carries some uncertainty, so applying a promising solution rather than waiting for a perfect one is itself exposure to uncertainty. [source: Dugas CPA 2000]
• Example language (illustrative): "If you wait for a solution that's guaranteed to work, you'll wait forever. What's a good-enough option you could try this week?"
• Watch for: clients who have good skills but don't use them. That is an orientation problem, so stay on this step longer. [synthesis]

4.12 Problem-solving skills training (Module 4)

• Purpose: give a structured way to act on worries about current problems instead of mentally rehearsing them. [source: Dunkley & Robichaud 2022; Dugas CPA 2000] The skills follow the standard social problem-solving sequence (D'Zurilla & Nezu tradition). [uncertain]
• Steps: [uncertain for step detail]
  1. Define the problem. State it concretely, separate facts from assumptions, and set a realistic, specific goal.
  2. Generate alternatives. Brainstorm many options without judging them yet, including small partial solutions.
  3. Decide. Weigh the main options for short- and long-term pros and cons, and pick a promising one rather than a perfect one.
  4. Implement and check. Plan concrete steps, carry them out, then review the result and adjust if needed.
  5. Practise on a real current problem from the diary, first in session and then as homework.
• Example language (illustrative): "Let's write the problem as something you could hand to a friend: what exactly is happening, and what would 'better' look like by the end of the month?"
• Watch for: endless option generation or comparison as a disguised safety behaviour (seeking certainty about the best choice). Set a time limit and move on. It is working when the client acts on the chosen option and worry about that problem falls. [synthesis]

4.13 Written exposure to hypothetical worries and core fears (Module 5)

• Purpose: process worries about remote or hypothetical situations that cannot be solved. The client repeatedly confronts the feared scenario in writing instead of avoiding it through worry. [source: Dunkley & Robichaud 2022; Routledge book description ("use written exposure to address lingering worries and core fears")] In the first edition this component was cognitive or imaginal exposure to core fears. [source: Dugas CPA 2000; uncertain: details of first edition]
• Before starting (safety and consent) [synthesis]:
  • Explain the rationale and that anxiety will usually rise at first. Get explicit agreement and agree a stop signal.
  • Screen out or postpone for: current suicidal intent or a scenario centred on suicide; unprocessed trauma memories that need a trauma protocol; psychosis; severe dissociation; active substance misuse used to cope; or a current crisis.
  • Scenarios are about feared outcomes, not rehearsals of harming anyone.
• Steps: [uncertain: exact procedure from the 2019 book]
  1. Choose a recurrent hypothetical worry from the diary.
  2. Find the core fear with a downward-arrow sequence, repeatedly asking what would happen next and what would be the worst part of that.
  3. Have the client write the scenario in the first person and present tense, ending at the feared outcome. Include sensory details, thoughts and feelings, with no reassuring endings.
  4. The client re-writes or re-reads the scenario repeatedly over several days, for a set period each time (often about 20–30 minutes), and rates anxiety before, at peak and after. [uncertain: duration]
  5. Review the anxiety ratings in session. Vary or deepen the scenario as anxiety falls.
  6. First-edition variant: the scenario was recorded and listened to repeatedly instead of written. [uncertain]
• Example language (illustrative): "We're going to do the opposite of what worry does. Worry jumps from one 'what if' to the next. Here we stay with the one you fear most, all the way to the end, and let your mind get used to it."
• Watch for: neutralising during or after exposure, such as adding "but it probably won't happen", mentally undoing the scenario or seeking reassurance. Watch for vague scenarios that skip the worst part, and for distress that does not reduce at all across several sessions. It is working when peak and end anxiety fall across repetitions and the client reports the theme now feels less gripping. [synthesis]

4.14 Relapse prevention (Module 6)

• Purpose: consolidate gains and prepare for setbacks. It takes the last one or two sessions in the version followed. [source: Bouchard et al. 2022; Dunkley & Robichaud 2022]
• Steps:
  1. Review what was learned in each module and which tools helped most.
  2. Repeat the IUS and PSWQ and compare them with baseline. [source: Dugas CPA 2000]
  3. Distinguish normal, everyday worry from a return to GAD-level worry, and a single lapse from a relapse. [uncertain: framing as standard CBT practice]
  4. Identify high-risk periods such as life transitions, illness and major decisions, and write a plan for setbacks. [source: Psychology Tools article notes planning for setbacks]
  5. Keep running ongoing experiments (4.9). [source: Psychology Tools article]
  6. Offer booster sessions where the service allows. [synthesis]
• Example language (illustrative): "Worry will come back now and then. That's normal. What would tell you it's more than a normal bad week, and what will you do first?"
• Watch for: a client seeking certainty that the gains will last. Treat that as one more uncertainty to tolerate. [synthesis]

5. Handling problems

The sources say little about troubleshooting. Unless a source is tagged, the guidance below is my own synthesis from the CBT-IU model and general CBT practice. [synthesis]

• The client seeks reassurance from you ("Do you think it's serious?", "Will this work?"). This is the modality's signature difficulty. Name it gently as a safety behaviour, decline to give the certainty, and turn it into an experiment. Illustrative: "I notice part of you wants me to make this certain. What if we leave it open and see how you manage with not knowing?" Agree this with the client in advance so it does not feel like withholding. [synthesis]
• Stuck: belief ratings about uncertainty don't move.
  • Check for hidden safety behaviours, such as mental checking, self-reassurance, doing the experiment only when "safe", or asking a partner afterwards.
  • Check that the experiments test the belief rather than a feared outcome.
  • Make the next experiment slightly bigger or in a new life area. [synthesis]
  • If IU stays high after the full protocol, consider a course of the experiments-only approach. Hebert & Dugas proposed it for the roughly 20–30% of clients who don't remit with standard CBT-IU and whose IU remains elevated. [source: Psychology Tools article]
• "But worrying works for me" or "stopping would be irresponsible" (resistance from positive beliefs). Go back to Module 2 for that specific belief, test it with a small time-limited experiment, and frame letting go of worry as something to try out rather than a permanent commitment. [synthesis; Module 2 content from Dunkley & Robichaud 2022]
• Non-adherence with the diary or experiments.
  • Find out whether the client thinks writing worries down will make them worse, whether they were unsure how to do the task "correctly", or whether they were avoiding.
  • An imperfect, half-done diary is itself an uncertainty experiment, so say so.
  • Shrink the task, set a cue such as a phone alarm, and start the exercise in session.
  • Fidelity in the version followed checks that every exercise is reviewed, so review it every time even when it wasn't done. [source: Bouchard et al. 2022 for the review requirement; rest synthesis]
• Overwhelm during written exposure.
  • Slow down rather than abandon. Write a less central version of the scenario first, shorten the period, and do the first exposure in session.
  • Ground the client before they leave.
  • If distress stays very high with no reduction across several repetitions, or the scenario leads to a trauma memory, stop. Reassess and consider a trauma-focused protocol before going on.
  • Don't let the client end each exposure on a reassuring re-write. [synthesis]
• The client turns problem-solving into worry (endless options, searching for the perfect solution). Time-box each step, have the client choose the "good enough" option, and treat acting on an imperfect plan as an uncertainty experiment. Applying a promising solution rather than waiting for a perfect one is the founder's own framing. [source: Dugas CPA 2000; rest synthesis]
• The worry is about a real, ongoing danger (domestic violence, an undiagnosed symptom, a debt deadline). Don't use exposure or experiments to help someone tolerate a real threat. Use problem-solving, safety planning and appropriate referral (medical review, legal or housing support) first. [synthesis]
• Suicidal thoughts or significant depression.
  • Assess risk with your service's standard procedure at intake and whenever mood drops.
  • If there is risk, make a collaborative safety plan, including lethal-means counselling about safe storage or removal, and adjust the pace.
  • Don't build written-exposure scenarios around suicide or self-harm.
  • Treat significant depression first or alongside if it blocks engagement. [synthesis]
• Ruptures ("You're saying my worries don't matter" or "These experiments are pointless"). Acknowledge that the concerns behind the worries are real and important. Clarify that the target is how the client handles not knowing, not what they care about. Invite the client to redesign the next experiment. Collaboration in designing experiments is a core principle of the approach. [source: Psychology Tools article for collaboration; rest synthesis]
• Experiments that "go wrong" (the feared outcome happens). Use the review step. How bad was it really, and how well did the client cope? Hebert & Dugas' approach asks what the result means for the belief, and coping with a negative outcome is informative too. [source: Psychology Tools article for reflection step; uncertain: coping question as a formal step; rest synthesis]
• Medication and benzodiazepine use. Don't change medication yourself. Coordinate with the prescriber. Note that the Laval group has studied CBT alongside benzodiazepine tapering (Gosselin et al., 2006). [uncertain: study cited from reference list] Using a benzodiazepine "just in case" can work as a safety behaviour, so discuss it in the formulation. [synthesis]
• Group delivery. Group members may reassure each other, so agree a group rule that members don't reassure but ask "what did you learn from not knowing?" Use group members' experiments as shared examples. [synthesis; group variant per Dugas et al. 2003]
• Remote delivery. CBT-IU delivered by videoconference showed adherence ratings and outcomes comparable to face-to-face. In that trial, a dedicated room and system were used, with backup by telephone and email for sending documents. Keep a backup contact route and a way to share worksheets. [source: Bouchard et al. 2022]
• Temporary rise in anxiety. Experiments and written exposure are expected to raise anxiety briefly. Warn the client in advance so a rise isn't read as treatment failure. [synthesis; the job notes list temporary anxiety as a plausible risk]

Sources

Sources

• Intolerance Of Uncertainty: Help Your Clients To Embrace The Unknown Using Behavioral Experiments (Psychology Tools). Secondary summary of Hebert & Dugas (2019).
• Cognitive Behavioral Treatment for Generalized Anxiety Disorder, 2nd Edition (Routledge). Publisher description and table of contents.
• Cognitive Behavioral Therapy for Generalized Anxiety Disorder: Targeting Intolerance of Uncertainty, Dunkley & Robichaud (Cambridge). Chapter summary only.
• A Multisite Non-Inferiority RCT of CBT for GAD Delivered by Videoconference, Bouchard et al. 2022 (MDPI J Clin Med)
• Generalized anxiety disorder: Differential diagnosis and cognitive behavioral treatment, Dugas CPA 2000 workshop summary (Memorial University)
• Further development of the intolerance of uncertainty model of GAD: a case series, Chigwedere & Moran (The Cognitive Behaviour Therapist). An adaptation, used only for the diary format and the worry-as-safety-behaviour framing.
• A Single-Component CBT for GAD (ClinicalTrials.gov NCT02552108). Only the title is known; the record content is not drawn on. [uncertain]

Books and papers cited (not drawn on)

• Robichaud, M., Koerner, N., & Dugas, M. J. (2019). Cognitive Behavioral Treatment for Generalized Anxiety Disorder: From Science to Practice (2nd ed.). Routledge.
• Dugas, M. J., & Robichaud, M. (2007). Cognitive-Behavioral Treatment for Generalized Anxiety Disorder: From Science to Practice. Routledge.
• Hebert, E. A., & Dugas, M. J. (2019). Behavioral experiments for intolerance of uncertainty: Challenging the unknown in the treatment of generalized anxiety disorder. Cognitive and Behavioral Practice, 26(2), 421–436.
• Dunkley, C. R., & Robichaud, M. (2022). Cognitive behavioral therapy for generalized anxiety disorder: Targeting intolerance of uncertainty. In G. Todd & R. Branch (Eds.), Evidence-Based Treatment for Anxiety Disorders and Depression. Cambridge University Press.
• Ladouceur, R., Dugas, M. J., Freeston, M. H., et al. (2000). Efficacy of a cognitive-behavioral treatment for generalized anxiety disorder. Journal of Consulting and Clinical Psychology, 68(6), 957–964.
• Dugas, M. J., Ladouceur, R., Léger, E., et al. (2003). Group cognitive-behavioral therapy for generalized anxiety disorder. Journal of Consulting and Clinical Psychology, 71(4), 821–825.
• Gosselin, P., Ladouceur, R., Morin, C. M., Dugas, M. J., & Baillargeon, L. (2006). Benzodiazepine discontinuation among adults with GAD. Journal of Consulting and Clinical Psychology, 74(5), 908–919.
• D'Zurilla, T. J., & Nezu, A. M. (2007). Problem-Solving Therapy: A Positive Approach to Clinical Intervention (3rd ed.). Springer.

Further reading (not drawn on): the Europe PMC full texts of Trenoska Basile et al. (2022) and af Winklerfelt Hammarberg et al. (2023). Session-level manual content therefore rests on the summaries above, and gaps are marked [uncertain].