THE SEMANTIC STATUS OF DIAGNOSTIC-CRITERIA FOR ORGANIC MENTAL SYNDROMES AND DISORDERS IN DSM-III AND DSM-III-R

After a general introduction referring to the contemporary debate abou t psychiatric classification, the nature of so-called ''diagnostic cri teria'' in psychiatry is discussed with special reference to DSM-III(- R) and to organic mental syndromes and disorders. A set of diagnostic criteria for a disease category can be intended alternatively (i) as s tating logically necessary and/or sufficient conditions for the diagno stic concept in question, or (ii) as providing contingent (probabilist ic) indicators of the discase. In one possible interpretation, a main aim of DSM-III and DSM-III-R has been to formulate type (i), logical c riteria, which amounts to an attempt to strictly identify syndromes or disorders with complex (polythetic) sets of easily observable symptom s and signs. It is shown that a logical interpretation would lead to s uch unwanted consequences for clinical and scientific practice that it could not possibly have been intended by the authors of DSM-III and D SM-III-R. But neither can the alternative interpretation in terms of t ype (ii), contingent or probabilistic indicators be consistently uphel d. The conclusion of the essay is that the semantic status of the diag nostic criteria in DSM-III and DSM-III-R is fundamentally blurred. Thi s unclarity may very well lead to divergent interpretations of the con cepts and to corresponding uncertainties in their clinical and scienti fic application.