You suspect a patient's speech shows a disturbance in the structure of their thinking. Before revealing the answer, decide how you would assess this.

Assess this best through spontaneous, relatively unstructured speech rather than simple yes/no questioning, since the disturbance shows itself most clearly when the patient has to organise their own ideas freely. Listen specifically for blended concepts, substituted ideas, overly literal use of language, or the intrusion of irrelevant material, since these are the characteristic ways the difficulty shows up. Consider whether a co-occurring cognitive deficit, particularly in chronic illness, might be contributing to or mimicking the presentation, since the two can be difficult to distinguish and often need careful assessment together, and note that formal thought disorder concerns how ideas are organised rather than what is believed, which points assessment away from the content of any beliefs expressed and toward the structure of the speech itself.