A computerized diagnostic system for comparing alternative classification schemes of depression

Critères diagnostiques, échelles et questionnaires utilisés au cours des dépressions

Les principaux instruments standardisés d’évaluation clinique de la dépression et de l’anxiété comprennent les critères diagnostiques, des échelles d’appréciation et des tests mentaux, principalement des questionnaires. L’utilisation systématique de critères diagnostiques rigoureux se révèle utile pour pouvoir constituer des groupes de Patients suffisamment homogènes pour les recherches cliniques. L'approche polydiagnostique représente, dans cette optique, une voie intéressante de recherche, permettant de ne pas être limité par un système de référence nosographique unique. Les systèmes permettant à ce jour la meilleure homogénéité des groupes de malades sont les critères du DSM III d’un épisode dépressif majeur, les critères de St-Louis de dépression primaire (Feighner, 1972), et les critères de dépression endogène (échelles de Newcastle; Roth, 1983), utilisés conjointement.

Certaines échelles de dépression ont fait l’objet de développements récents en Europe comme la MADRS, l’échelle de ralentissement dépressif de Widlocher, l’échelle d évaluation de la dépression de Pichot et l’échelle manie-dépression du système AMDP. Il en est de même pour certains questionnaires ou check-lists comme le questionnaire HAD, la HSCL, les échelles visuelles analogiques de Norris ou la CHESS, check-list d’évaluation des symptômes somatiques. La sensibilité au changement de ces divers instruments en fait leur principal intérêt pratique.

Recognition and subtyping of atypical depression by French Practitioners

A two-part survey of French General practitioners was carried out to determine attitudes and diagnostic criteria for definition of atypical depression, major depressive episodes, and anxiety disorder. Following a preliminary phase in which 90 physicians were interviewed, 500 general practitioners received detailed questionnaires based upon DSM III-R criteria, as well as supplementary questions based upon the Leibowitz and Akiskal criteria. Principal criteria analysis and regression analysis were carried out on the 280 analyzable files received. Results showed that anxiety disorders were primarily defined in terms of somatic criteria, and that there were a number of factors common to anxiety and depression. Minor depression was also defined primarily on the basis of somatic complaints, together with loss of energy and fatigue. Major depression was defined primarily by asthenia, apragmatism and loss of drive, together with less strongly weighted cognitive factors (sadness, Pessimism, inhibition, etc). From a dimensional standpoint, depression is defined as a “vital deficit”, with a failure to cope with social and environmental demands. It is interesting to note that the duration criterion was not considered to be of nosological relevance by the physicians, and was generally ignored in the definition of mental pathologies. The international subtyping of depressive disorders does not form part of the Practice of French practitioners, who prefer to retain the older, psychosocial models.

A polydiagnostic study of depressive disorders according to DSM-IV and 23 classical diagnostic systems

The classification of mood disorders is one of the most highly debated topics in modern psychiatry. The introduction of DSM-III (and its followers) has set a new standard in this controversy but little empirical evidence is available as to how the various classical diagnostic categories of mood disorders by Kraepelin, Schneider, Leonhard, Hamilton, Kielholz, Winokur and others compare with this new standard. The Intensive Prospective Study arm of the Group for Longitudinal Affective Disorders Study has studied a broad spectrum of mood disorders in 23 participating centres from all over Japan with a polydiagnostic semistructured interview called Comprehensive Assessment List of Affective disorders. In this paper we examined how the various classical diagnostic systems of depressive disorders correspond to the DSM-IV diagnoses, and found the following: (1) The classical 'neurotic' or 'psychogenic' depressions are diagnosed as major depression and not as dysthymia in DSM-IV; although dysthymia was dubbed as 'depressive neurosis' in DSM-III, its criteria were not true to the traditional usage of the term. Viewed from the other side of the coin, DSM-IV can be said to stand in the unitary tradition. (2) Some of the classical diagnostic categories such as Schneider's depressive psychopathy and Klein's acute dysphoria as well as modern ones such as Akiskal's subaffective dysthymia and Angst's recurrent brief depression were rarely seen in traditional psychiatric treatment settings. (3) Comparisons of the unique diagnostic systems such as those by Leonhard, Winokur and Berner warrant further studies on their validity.

The validity of the assessment of psychopathology in the psychoses

This paper reviews recent progress in the assessment of the psychopathology of psychosis and focuses upon a number of persistent limitations. In particular the over-emphasis upon reliability at the expense of validity is highlighted and the relationship between reliability and validity is reconsidered. A number of strategies aimed at improving the validity of psychopathological measures are outlined. Proposals to deploy such variables differently in research strategies and analyses are endorsed.

Methuselah--an expert system for diagnosis in geriatric psychiatry

This report is based on the notion that criteria for "successful" diagnosis differ for different medical specialties. Diagnostic judgement in highly unstructured task domains is best characterized as clinical problem formulation with pragmatic implications for interventions. This concept is illustrated by the implementation of a computer-based diagnostic expert system for geriatric psychiatry. The program begins with guiding the patient's interview by the clinician. This is followed by the diagnostic process which is conducted in three steps. In the first step, candidate syndromes of disease states are identified by matching the presenting complaints with symptom lists of clinical syndromes. In the second step, the candidate syndromes serve as the organizers for gathering additional patient data (e.g., information from referral source and past illnesses) to seek constellations of findings which form a coherent clinical context. In this phase, the program can also prompt the clinician to obtain additional information from the patient or other available sources to resolve conflicts or, if necessary, invoke the concurrent presence of two independent syndromes to attain convergence (i.e., minimize the number of unexplained findings). In a final step, the syndromes with highest credence value, reflected by the number of linkages to patient data, are sharpened to specific diagnostic formulations. This is accomplished by frames of diagnoses which are associated with each syndrome. Once again, the patient data can be consulted to achieve optimal matches. A summary statement to the clinician lists the essential supporting evidence for the chosen diagnosis and can communicate alternatives or unresolved issues for clarifying interventions. Although no decisive evidence is available, informal observations of clinicians support the notion that clinical reasoning in highly unstructured domains is largely contextual and seeks apprehension of "gestalts" in successive steps. The diagnostic program of this report aims at simulating this process.

A polydiagnostic scale for dimensional classification of endogenous depression. Derivation and validation

Several operational diagnoses (OPD) for endogenous depression have been proposed. However--though aiming at similar clinical concepts--the amount of association and agreement between different OPD is rather low. In this study the relationship between eight OPD (Research Diagnostic Criteria, DSM-III, Michigan Discrimination Index, Newcastle Scale I, Newcastle Scale II, Taylor-Abrams Criteria, Vienna Research Criteria, Hamilton Endogenomorphy Index) was assessed by applying latent trait analyses to the classificatory data of these eight OPD which were rated simultaneously in a sample of 173 depressive inpatients. According to these analyses six OPD (RDC, DSM-III, NCS-I, NCS-II, TAC and VRC) are tapping the same phenomenon. This latent trait represents compatible concepts of endogenous depression; it is strongly associated with the independently assessed clinical ICD-9 diagnosis of endogenous depression. The six OPD can be considered as items of a scale (so-called OPD-scale). The total scores of the OPD-scale represent a dimensional assessment of the decisiveness of the diagnosis endogenous depression. Coefficients and parameters of this new scale are presented.