[Formal representation of the cognitive-behavioral assessment in obsessive-compulsive disorder]

Psychological assessment is a crucial and important part of psychologist's work. Despite this, tools utilized by clinicians are often inadequate and methods used to investigate and make decisions on the basis of collected data are even logically incorrect. In this paper two mathematical psychology theories (Knowledge Space Theory and Formal Concept Analysis) are employed to propose a method for collecting diagnostic information. The conjoint application of these two theories allows to build a hierarchical structure composed by diagnostic elements. This structure is very similar to the one determined by the clinical diagnostic process. Correct logical inferences on the patient's situation, and an exact depiction of those diagnostic elements presented or not by the patient, represent the potential advantages of such a methodology. An applicative example on Obsessive-Compulsive Disorder (using the background determined by two shared diagnostic tools i.e. DSM IV-TR and CBA 2.0) is presented. Finally, the opportunity to build an adaptive assessment procedure from the derived structure is investigated.