Fig. 2.

(a) Example of a CBM-pa intervention item: an intervention item presents an ambiguous situation in the trial format shown. In this example a common interpretation is that the cut was accidental, but many patients with paranoid symptoms would interpret the cut as deliberate. Each intervention trial uses a word task and question to guide patients into making helpful, rather than paranoid, interpretations. In this example, if participants enter the wrong letter they are given a ‘clue’ (more letters appear) and if still wrong, the correct completed word is shown. Likewise, the question is carefully constructed such that it always reinforces the non-paranoid interpretation of the preceding passage (the cut is the result of inexperience). To answer the question ‘correctly’ participants must endorse the non-paranoid meaning and cannot continue until they do so. If the ‘wrong’ answer is given a feedback message indicates ‘that is one answer, is there another possibility?’ (b) Example of an active control (neutral text-reading) item: a control item is identical in format and manner of delivery to an intervention item, the only difference is the textual content and its meaning. Control items relay factual information which is unambiguous and emotionally neutral. The word completion and question remains neutral and factual.