Mental health articles

The Recent DSMs-III, III-R, AND IV

As already noted, there has been considerable activity in recent years in forming new psychiatric diagnostic systems. Three revised diagnostic manuals have been published in just 14 years. Furthermore, these manuals were considerably larger than their predecessors, and the approach and methods for producing them differed in important ways. These new diagnostic manuals manifest a definite sensitivity to the criticisms made of the older systems. The authors have been particularly sensitive to issues of definition and reliability, and the new diagnostic systems have stimulated a considerable amount of research .

Some of these studies are reviewed here briefly, mainly to illustrate methodological issues. In many respects, DSM-III was a radical departure from its predecessors. Its authors attempted to avoid any theoretical partisanship or controversies, and they also attempted to emphasize operational criteria and descriptive psychopathology. ‘‘These criteria are based, for the most part, on manifest descriptive psychopathology, rather than inferences or criteria from presumed causation or etiology, whether this causation be psychodynamic, social, or biological. The exception to this is the category of organic disorders whose etiology is established as caused by central nervous system pathology’’.

However, this distinction for organic disorders was omitted in DSM-IV. ‘‘The term ‘organic mental disorders’ has been eliminated from DSM-IV because it implies that the other disorders in the manual do not have an ‘organic’ component’’. This change appears to reflect political-guild issues more than diagnostic ones, and I will say no more about it here. Although some have criticized the deliberate avoidance of a theoretical approach to diagnosis (Follette & Houts, 1996; Skinner, 1986), the authors of DSM-III, as well as DSM-III-R and IV, emphasized the need for accurate description and reliability of diagnosis and even carried out reliability studies, particularly for DSM-IV. Let us now turn to some studies of reliability and related issues. In one study, twenty psychiatrists made independent diagnoses on twenty-four actual case histories of childhood psychiatric disorders. The average agreement of these clinicians with the authors’ consensus on the expected DSM-III diagnosis was just less than 50%. In another report on this study, the average agreement between the psychiatrists on their most common diagnosis (they were allowed more than one) was 57% for DSM-II and 54% for DSM-III. Interrater agreement for DSM-III reached 80% for only four of the twenty-four cases; the best results were obtained for diagnoses of mental retardation. Noteworthy disagreement was noted in both systems for anxiety disorders, complex cases, and in the subtypes of depression. The lack of agreement among the different diagnostic systems and the fact that they tend to select different samples of subjects for the same diagnostic category has also been noted by others. In the study by Endicott et al. of diagnostic criteria for schizophrenia, six well-known systems were used to evaluate newly admitted patients including the Research Diagnostic Criteria (RDC), the Feighner Criteria, and DSM-III. ‘‘The most salient finding of the study is that the systems vary greatly in the rates at which they make the diagnosis of schizophrenia’’. The percentage of cases diagnosed as cases with schizophrenia ranged from 3.6 to 26%, a sevenfold difference, although most systems showed acceptable rater reliability. ‘‘The disparity illustrates the degree of difficulty associated with the diagnosis of schizophrenia and in the concept of schizophrenia …’’. A somewhat similar study of forty-six cases of schizophrenia was reported by Klein who compared seven diagnostic systems including most of those evaluated by Endicott et al.. These patients had to have a hospital diagnosis of schizophrenia based on DSM-II, a score of four or more on the New Haven Schizophrenic Index, and be under age 56 with no evidence of organic brain damage, toxic psychosis, drug abuse, and the like. The DSM-III correlated .89 with the Feighner Criteria and .84 with the RDC, diagnostic systems which were models for it. However, its correlations with the remaining four scales were considerably lower. Use of the DSM-III led to diagnosis of 28% of the sample as cases of schizophrenia; the range was 24 to 63% for the other diagnostic systems. Furthermore, only nine of the forty-four patients were diagnosed by all seven systems as either cases of schizophrenia (N = 3) or as not such cases (N = 6). Somewhat comparable findings were reported in a more recent study. ‘‘The aim of this study was to determine the extent to which diagnoses of schizophrenia from forensic sources can be seen to meet formal diagnostic criteria through use of both a structured undiagnostic approach and a multidiagnostic chart review based on case histories’’. Each of the eightythree subjects had a recorded diagnosis of schizophrenia at coronal autopsy. Thirty one percent did not meet the criteria for any of the five diagnostic systems, 68.7% met criteria for at least one system, and 20.5% met the criteria for all five diagnostic systems. Agreement ranged from 42.2% for the Feighner criteria to 63.9% for DSM-III-R. Although it seems reasonably clear that DSMIII, DSM-III-R, and DSM-IV are more precise in their delineation of many mental disorders than was true of DSM-II and that the reliability of diagnosis has been enhanced in many instances, some important problems remain. The lack of comparability of diagnostic systems has already been noted, and this clearly presents problems for both research and practice. If everyone adhered to one diagnostic system exclusively, then perhaps this problem would be less serious. However, when new official systems are introduced within a period as brief as seven years, the comparability and meaningfulness of clinical diagnosis becomes more problematic. DSM-IV, for example, was being prepared while research studies on DSM-III-R were still underway. Thus, although the DSM-IV Task Force profited from the research and data sets resulting from DSM-III, it could have learned more by awaiting additional research based on DSM-III-R.

In the introductory section of the DSM-III-R manual, it is stated that the American Psychiatric Association decided in 1983 to work on a revision of DSM-III for several reasons. Data from new studies were inconsistent with some of the diagnostic criteria. ‘‘In addition, despite extensive f ield testing of the DSM-III diagnostic criteria before their official adoption, experience with them since their publication had revealed, as expected, many instances in which the criteria were not entirely clear, were inconsistent across categories, or were even contradictory’’. Therefore, a thorough review was instituted, and the required modifications were made. Although the revised DSM-III essentially follows the same overall scheme and rationale as the original, some modifications were made and comparisons of the two diagnostic systems have been reported. Some examples of the problems encountered follow. One study attempted to evaluate the reliability, sensitivity, and specificity of DSM-III and DSMIII-R criteria for the category of autism in relation to each other and to the clinical diagnoses made. The subjects were fifty-two individuals diagnosed as autistic and sixty-two considered developmentally disordered but not autistic. The reliability of the specific criteria tended to be high. The DSMIII criteria were judged more specific but less sensitive than the DSM-III-R criteria. As a result, the investigators concluded that the diagnostic concept of autism has been greatly broadened in the revised system. In the light of the preceding paragraph, it is of interest to list the changes made for autistic disorder in DSM-IV: Autistic Disorder.

Tags: diagnosis, DSM-IV, Health, mental, Mental health