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Theory A / Theory B

Human beings actively try to understand their world and what happens to them. However, these understanding can be inaccurate or unhelpful. Worse, unhelpful beliefs often drive unhelpful behaviors that can serve to inadvertently reinforce the original belief. Therapists can find it challenging working with client appraisals of a problem. One powerful way of working with problematic client appraisals is to frame their belief as a ‘theory’ or ‘hypothesis’ about how the world works. Theory A / Theory B, sometimes referred to as the “dual model strategy” is a powerful and flexible technique for introducing alternative accounts of a problem: it is a collaborative framework for formulating client problems; a method for assessing a client’s conviction in their ‘theory A’; a framework for generating alternative or more helpful ways of interpreting a problem (a cognitive restructuring tool); a way to guide or scaffold the process of data gathering (“how could we find out which theory is the best way of explaining the data?”) which can lead to behavioral experiments.

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Introduction & Theoretical Background

“The most effective way of changing a misinterpretation … is to help the person come up with an alternative, less threatening interpretation of his or her experience.” (Salkovskis, 1996) Human beings actively try to understand their world and what happens to them. The clients we see in therapy are no exception. Clients who are struggling with difficulties often hold on to beliefs which help them to explain what is happening. For example: One problem is that the beliefs clients hold can sometimes be inaccurate ways of understanding their experience. Worse, their unhelpful beliefs often drive unhelpful behaviors that can serve to inadvertently prolong or reinforce the original belief. For example:
  • The client with panic disorder believes that her racing heart means that she is likely to have a heart attack. She stops exercising, which reduces the opportunities she has to learn that her heart is healthy and can beat quickly without going into cardiac arrest.
  • The client with OCD believes that his intrusive thoughts of children means that he is a paedophile. He tries to suppress his thoughts which leads (via the rebound effect) to him experiencing more such thoughts. He tries to avoid children, which makes his encounters with them feel even more significant and emotionally charged.
  • The client with PTSD believes that her flashbacks mean that the perpetrator of her abuse is nearby and that she is in danger. She tries to avoid all reminders of her trauma, which means that her memories do not get ‘processed’, her flashbacks do not get better, and she continues to feel a heightened sense of threat.
Therapists can find it challenging working with client appraisals of a problem: even when alternative explanations are entertained clients may fail to experience a ‘felt sense’ of change. As Salkovskis and colleagues (1999) summarize: “Do not expect patients simply to change their views as a result of discussions and the construction of an alternative explanation. “Don’t trust me, test it out for yourself’’ is the explicit theme of therapy sessions subsequent to the therapist and patient agreeing on a possible, anxiety based alternative account of their problem.” One helpful way of working with problematic client appraisals is to frame their belief as a ‘theory’ or ‘hypothesis’ about how the world works. Just like a scientist, the client is using theory with which to explain the evidence.
  • “So, given the evidence that you are having headaches your theory is that you have brain cancer.”
  • “We can think about your symptoms as a kind of evidence. You’ve told me that one of your experiences is that you keep having intrusive images of harm coming to your loved ones. And you’ve formed a theory about why that might be – you told me that your theory is that you must be having these thoughts because you’re an evil person.”
Theory A / Theory B, sometimes referred to as the “dual model strategy” (Wells, 1997), is a powerful and flexible technique for introducing alternative accounts of a problem: it is a collaborative framework for formulating client problems; a method for assessing a client’s conviction in their ‘theory A’; a framework for generating alternative or more helpful ways of interpreting a problem (a cognitive restructuring tool); a way to guide or scaffold the process of data gathering (“how could we find out which theory is the best way of explaining the data?”) which can lead to behavioral experiments. This Theory A / Theory B worksheet includes three case examples illustrating a range of client experiences.

Therapist Guidance

This technique can be used when clients hold threatening beliefs about their experiences (theory A) – for example, that these experiences are dangerous to themselves, or to those around them. A helpful approach is to introduce the possibility of there being an alternative or competing hypothesis (Theory B). Helpful analogies include those of a scientist or police detective.
  • Scientist: When science works well, a scientist will start with some data – some facts or observations – and then they will try to develop a theory to explain the facts. Sometimes the theory will be wrong, but that’s OK because finding out that it’s wrong means that the scientist can come up with a better – more accurate – theory. As an example, an ancient belief was that tooth decay was caused by a ‘tooth worm’. In the 17th century a French physician came up with a new theory that tooth decay was caused by sugar. It wasn’t until the 1890’s that an American dentist carried out experiments to prove that bacteria in the mouth consumed sugar and produced acids which cause tooth decay.
  • Police detective: Bad practice in police work is to have a prejudice or hunch, and then look for evidence that fits your hunch. So when a crime is committed a bad police officer will assume that it was done by a particular person, and will then look for evidence to ‘prove’ that person did it. In essence, they will look where the light is shining. The danger is that there will be a miscarriage of justice. Best practice in police work is keep an open mind for as long as possible so that you don’t gather evidence that just proves your prejudices. The best detectives are the ones who ask “what do I notice?”, and “what are the facts here?”. Once they have all the evidence they might try to fit different theories to explain the facts. If they are really good, they might have multiple theories and compare them to see which ones fit the facts the best.
  1. Describe how the client sees the problem now (theory A). Elaborate your understanding of their belief. Ask the client to rate their conviction in their belief.
    • What’s your belief about your problem now?
    • How do you understand what’s going on for you?
    • How long have you believed this?
    • How much do you believe this now?
  2. Explore the reasons why the client has arrived at this belief.
    • Why do you believe this?
    • What makes you believe this?
    • What makes you so sure?
    • What has happened that has led you to think this way?
    • What is your evidence for this belief?
    • Are there any specific ‘lightbulb’ moments’ that are significant here? Has anything profound happened that has made you think this way?
  3. What does the client need to (continue to) do if theory A is true? This section reflects what the client is already doing to cope as a result of believing theory A. The therapist can explore what the client does in terms of avoidance or safety behaviors.
    • What would anyone do if they believed theory A with 100% conviction?
    • What are you doing because of this belief?
    • What do you have to pay attention to because of this belief?
    • What do you to prevent bad outcomes from happening?
    • Is there anything that you do to keep yourself or others safe?
  4. Encourage the client to think about the long-term consequences of living life according to theory A.
    • What would life look like in 1, 5, or 10 years if you continue to live life according to theory A?
    • Are there any things that it would stop you from doing?
    • What might you have to miss out on if theory A is true?
    • Consider effects upon different life domains such as work, relationships, recreation, emotional life, energy.
  5. The purpose of the Theory A / Theory B technique is to open a discussion about the possibility of alternative ways of thinking about the client’s problem, and then to explore how the current data fits with different theories, and to guide the gathering of new data that can test theories. When using the Theory A / Theory B technique the therapist’s aim is to help clients to develop a less threatening or more helpful / realistic way of appraising the problem. Sometimes this means:
    • Reframing the original belief about the problem in the light of new information, such as therapist psychoeducation, normalization, survey data, data gathered in session. (e.g. a client who believed he was a risk to other people because he had intrusive thoughts of harming others, and was able to contemplate other possibilities when his psychologist showed his a list of common intrusive thoughts)
    • Reframing the problem as one of worry (e.g. with a client who struggles with health anxiety “I have cancer” > “I’m struggling with health anxiety and I worry that I have cancer”).
    • Reframing the problem as one of caring too much (e.g. with clients with OCD who strongly hold beliefs about how much they are responsible).
    • Assessing the client’s readiness to engage in CBT by eliciting conviction ratings in the new belief.
    Questions you might ask:
    • What is another way of thinking about the problem?
    • Confronted with the same evidence, how would other people think about it?
    • Even if you don’t believe it, what might be another way of looking at it?
    • Has anyone else suggested other ways of making sense of what is happening for you?
    • You’ve believed for a long time that your symptoms mean theory a, what would you prefer to believe about them?
  6. The next step is to elicit any evidence that the client already has that is consistent with theory B.
    • Is there any reason to think theory B might be true?
    • What would a close friend say about theory B?
    • If you were defending theory B in court, what evidence would you use?
    • Are there any times when you don’t use your safety behaviors? What happens? What does that mean?
    • Is there any evidence that fits both theory A and theory B?
  7. Now that an alternative interpretation has been generated and elaborated, the role of the therapist is to encourage clients to explore ways to test which theory is true. This might consist of conducting an experiment to test theory A vs theory B, finding evidence to support theory B, or finding evidence to undermine theory A.
    • How could you test whether theory A or B is the best explanation?
    • What behavioral experiments could you do to test whether B is true?
    • If theory B were true, what would it be safe to do? What would you do?
    • What fears would I need to face to find out whether theory B is true?
    • What might I need to tolerate in order to find out whether theory B is true?
    • What kind of information would I need to know to find out whether theory B is true?
    • It looks like theory B could be true. How might we find out?
  8. Contemplating behavioral experiments can be a daunting experience for clients. Encouraging clients to imagine that theory B is true can help them to connect with their goals and values, and can increase their motivation to face their fears.
    • If theory B were true, how would you be living your life differently?
    • What effect would it have on your work / relationships / recreation / emotional life?
    • What would a typical day look like?
    • What would life look like in 1, 5, or 10 years ?

References And Further Reading

  • Wells, A. (1997). Cognitive therapy for anxiety disorders. John Wiley & Sons.
  • Salkovskis, P. M. (1997). Frontiers of cognitive therapy. Guilford.
  • Salkovskis, P. M., Bass, C. (1997). Hypochondriasis. In The Science and Practice of Cognitive Behaviour Therapy (eds Clark & Fairburn). Oxford: Oxford University Press.