Published online by Cambridge University Press: 06 October 2014
In this article we address the relationship between behavioural assessment and psychiatric diagnosis. We argue that a diagnostic formulation should be made prior to behavioural assessment but consider diagnosis as complementary to traditional behavioural assessment. Implicit in our proposal, is the notion that behavioural practitioners should be thoroughly conversant with the various forms of psychopathology, and be able to identify the signs and symptoms that cluster together to constitute a clinical syndrome or disorder. The same practitioners should be able to differentiate the signs and symptoms of one syndrome or disorder from another. It is further proposed that behavioural practitioners need to be aware of the limitations and boundaries of their particular approaches and concede the value of other treatment approaches (especially chemotherapy) derived from different theoretical perspectives (Hersen 1979, 1981; Kazdin and Hersen, 1980). Such approaches may assume priority in the treatment of certain disorders, e.g., the first-rank symptoms of schizophrenia.
The term diagnosis means “to know through” and is simply a hypothesis about the nature of a problem (Rush, 1982). Ideally, a diagnosis should simplify complex data; provide information about the likely outcome of a particular psychiatric disorder with and without treatment; allow improved prognostic judgements; assist in the selection of appropriate treatments; allow communication between professionals; and lead to improved clinical strategies (Kendell, 1974; Rush, 1982).