Dissociative Disorder Not Otherwise Specified: a Clinical Investigation of 50 Cases with Suggestions for Typology and Treatment

Although the DSM-III-R lists six examples ofsubcategories of dissociative disorder not otherwise specified (DDNOS), the literature contains little about DDNOS proper, and only one subcategory, Ganser syndrome, has been studied in any depth, all studies having been completed before its inclusion under DDNOS in 1987. This is a comprehensive study of 50 individuals with DDNOS. Data from clinical history, mental status examination, collateral interviews, neurological examination, electroencephalogram (EEG), intelligence testing Minnesota Multiphasic Personality Inventory (MMPI), and the Dissociative Experience Scale (DES), were analyzed on 50 consecutive individuals diagnosed with DDNOS by DSM-III-R criteria. The data suggest a number of different diagnostic subcategories including childhood dissociative disorder, ego-state disorder, dissociative psychosis, nocturnal dissociative disorder, gender identity disorder (dissociative type), and a truly not otherwise specified type. Each of these subcategories will be described including case vignettes and supportingdatafrom previous studies and papers. Nosological issues are discussed as well as treatment implications.