What is IBA?
How do IBA & CBT compare?

What is IBA?

Inference based therapy (IBT) is grounded in an inference based approach (IBA) to OCD which emphasizes the role of reasoning in the development and maintenance of OCD. The treatment is based on the central idea that obsessions are doubts that arise due to reasoning errors (e.g. “I might have left the stove on”; “I might be contaminated”; “I might be a deviant”). According to this approach, such doubts entirely rely on an imaginary narrative, making obsessional doubts feel very real, even though they have no basis in reality. However, because this is often not completely recognized by the person with OCD, due to a confusion between imagination and reality during reasoning, these doubts continue to persist and remain unresolved.

IBT aims to bring resolution to obsessional doubts by showing the client how obsessional doubts come about due to reasoning errors, and how these errors in reasoning completely invalidate the reality of obsessional doubts. The client is educated that obsessional doubts are not the same as normal doubts. Normal doubts come about for legitimate reasons, whereas obsessional doubts always come about without any basis in objective reality. Also, the client is shown how an underlying imaginary narrative gives credibility to the doubt, and is encouraged to explore alternative narratives that are more in line with reality and the senses. Throughout treatment, the client is taught to trust objective reality and their senses within OCD-triggering situations. Consequently, the client realizes that any compulsive acts are superfluous and able to no longer engage in compulsive behaviours.

Treatment outcome studies have shown IBT to be an effective treatment for OCD. It is also an effective treatment for the treatment of resistant cases of OCD, and those who have been unable to benefit from other treatments.

As of 2017, around forty empirical papers have been published on inference-based therapy. In particular, two randomized controlled trials showed that inference-based therapy was as efficacious as cognitive-behaviour therapy for obsessive-compulsive disorder. For further reading, please see published scientific articles by visiting our Tools and References page.

How do IBA and CBT compare?

Inference Based Treatment (IBT) is a cognitive-behavioral treatment (CBT), but is different from CBT from how it is usually applied in treating OCD. The main difference is that an Inference Based Approach (IBA) has a different explanation on the cause of OCD than most other cognitive models. And because of these different explanations, the cognitive and behavioral techniques IBT utilizes in treating OCD are not the same than those applied in standard CBT.

Standard CBT is based on the idea that intrusive cognitions and doubts are normal, but that these thoughts develop into obsessions depending on how the person interprets them. For example, according to this approach, a person with thoughts about harming someone will develop obsessions if these thoughts are given importance or negatively interpreted. If on the other hand, they are simply dismissed as insignificant thoughts by the person with OCD then they will no longer provoke distress and cause compulsions. For this reason, cognitive interventions in standard CBT are often focused on changing the appraisal of intrusive cognitions in OCD so that they no longer provoke distress and compulsions.

IBA views this explanation of OCD as incorrect. While it is true that intrusive thoughts are normal, and they occasionally occur to everyone, something very different is happening when a person has OCD. In fact, in IBA to OCD, there is no such thing as an “intrusion”. Instead, in IBA, obsessions are conceptualized as inferences or doubts (e.g. “I could be a child molester”; “I might be contaminated”) that do not arise in the same way as intrusions in the general population. Instead, they come about through reasoning, which occurs prior to any appraisal. Moreover, in the case of OCD, these inferences or doubts are the result of specific reasoning errors, which makes these thoughts feel very real, even though they are false and incorrect. Consequently, cognitive interventions in IBT focus on teaching people with OCD to identify the reasoning errors that lead to obsessions. And by realizing how obsessions are incorrect, negative appraisals and compulsions will naturally disappear.

So the treatment targets of IBA and CBT are very different. IBA focuses on how obsessions arise due to reasoning. CBT focuses on the consequences of the intrusion or obsession. We can schematically present this as follows:

Figure 1. Illustration of the principal cognitive treatment targets of the Inference Based Approach (IBA) and standard Cognitive-Behavioral Therapy (CBT) in the obsessional sequence.

Another important difference between IBT and standard CBT is that IBT does not include exposure in vivo and response prevention (ERP). This behavioral technique consists of exposing oneself to feared objects and situations without engaging in any rituals or compulsions to overcome OCD. However, while this can be an effective technique, not all OCD patients benefit from ERP and there are a lot of people with OCD who have difficulty completing the exercises needed for this approach to work. However, it is still an important part of standard CBT, often more so than cognitive interventions.

IBT is a far more cognitive approach. The reason is that when the cognitive interventions in IBT are successful, which aim to show the person with OCD that the obsession is false, then there is no reason to be distressed anymore, nor is there a need to engage in rituals or compulsions. IBT does involve doing certain things, but these focus on learning how to trust reality in OCD triggering situations, not by repeated exposure to feared objects to habituate to it.

In sum, standard CBT focuses primarily on behavioral techniques, as well as the appraisal of intrusive cognitions, by helping the person to no longer give these thoughts significance and importance to relieve distress and compulsions. IBT focuses on helping the person to achieve resolution of obsessional doubt by seeing how obsessions are false and incorrect, because once the obsession is no longer experienced as a credible doubt or idea, distress, negative appraisal and compulsions will naturally disappear.