Stability of DSM-III-R diagnoses: study of a case register

We studied the diagnostic stability and the factors associated with it in 1,443 psychiatric patients with multiple admissions for a period of 45 months. We successively considered the whole population, the psychotic and then the schizophrenic patients. Demographic and DSM-III-R diagnostic information was collected on a computerized database. During the observation period, 1,443 patients were hospitalized twice or more. Diagnostic stability ranged from 34 to 86%. Psychotic disorder was the most stable, whereas adjustment and anxiety disorders were the least stable. Among schizophrenic patients, higher stability appeared for residual and disorganized types (83 and 71%, respectively). Statistical analysis did not show any variable associated with change, apart from the diagnoses themselves. The reasons that could explain changes are discussed, as well as the clinical consequences of these shifts.     

A comparison of clinical and research DSM-III-R diagnoses of schizophrenia in a Finnish national birth cohort

As a prerequisite to the use of the Finnish National Hospital Discharge Register in psychiatric epidemiological research, we studied the diagnostic reliability of the register in terms of the psychiatric morbidity experienced by a national birth cohort. We investigated all entries to the register for a sample based upon the Northern Finland 1966 birth cohort at the age of 16 years (n=11017). Until the end of 1993 (age 27 years), a total of 563 subjects had a register diagnosis indicating a psychiatric illness, 37 of them being schizophrenia. When operational criteria (DSM-III-R) were applied to clinical information in the available original hospital records for cases of psychosis, personality disorder and substance abuse (n=249), 71 fulfilled criteria for schizophrenia, including all of the 37 cases in the register and an additional 34 (48% false-negatives), most frequently diagnosed in the register as schizophreniform or other psychosis. Despite the official use of DSM-III-R nomenclature, it appears that the clinical concept of schizophrenia in Finland, manifest within the register, remains very restrictive. The application of operational criteria is a necessary prerequisite for scientific research on schizophrenia.     

The antecedents of schizophrenia: a review of birth cohort studies

Background: Birth cohort (BC) studies demonstrate that individuals who develop schizophrenia differ from the general population on a range of developmental indices. The aims of this article were to summarize key findings from BC studies in order to identify areas of convergence and to outline areas requiring further research. Method: We define BC studies as studies based on general population BCs where data are collected prospectively from birth or childhood and which identify schizophrenia or related disorders as an outcome. To identify such studies, we searched various electronic databases using the search parameters (schizo* OR psych*) AND (birth cohort). We also checked the references of relevant articles and previous reviews. Results: We identified 11 BCs from 7 countries that have examined schizophrenia as an outcome in adulthood. There is relatively consistent evidence that, as a group, children who later develop schizophrenia have behavioral disturbances and psychopathology, intellectual and language deficits, and early motor delays. Evidence with respect to alterations in language, educational performance, and physical growth has also been identified in some studies. BC studies have also contributed evidence about a wide range of putative risk factors for schizophrenia. Conclusions: BC studies have provided important, convergent insights into how the developmental trajectory of individuals who develop schizophrenia differs from their peers. The combination of new paradigms and larger cohorts, with the tools of modern epidemiology and biomedical science, is advancing our understanding of the developmental pathways to schizophrenia.     

The course of mild dementia in a birth cohort

The mental health of a birth cohort has been followed until the age of 87 years. The cohort consists of all Icelanders born during a period of three years. Only three probands were lost in the follow up period from 61 to 87 years. The diagnoses were made by two methods: an indirect method based mainly on information provided by general practitioners, and the computerized diagnosis AGECAT. Many cases diagnosed as mild dementia by the indirect method had no or very few cognitive symptoms when the AGECAT was applied. The diagnosis of mild dementia is associated with high mortality. Almost 30% of cases of mild dementia diagnosed by the indirect method before the age of 75 years have no symptoms of dementia at the age of 81 years and more than 10% continue to have mild symptoms. Similar results are found at the age of 87 years. Atherosclerotic disorders are present in 48.6% of cases of mild dementia and 58.6% of severe dementia in contrast to only 25–30% of probands with a effective disorder or without psychiatric diagnosis.     

Concepts of psychiatric diagnoses: a further investigation of the reliability of psychiatric diagnoses (author's transl)]

A total of 128 physicians and psychologists, working in six psychiatric hospitals, were asked to allocate 10 psychiatric diagnoses on the basis of typical clinical criteria (symptoms, course of illness, etiological and anamnestic data), with which they were supplied. The correct diagnosis was made in 45.3%, while in 82% the broad diagnostic group was correctly ascribed. The respondents were divided into two groups, according to the amount of diagnostic data they had been given (though in fact the information necessary for differential diagnosis was given equally to both groups). The group which made diagnosis on the grounds of more comprehensive data (ten characteristic diagnostic items) did significantly worse them the group which had few data (six characteristic items). The stereotypes for mania, endogenous depression, obsessional-compulsive neurosis, and antisocial personality disorder were correctly defined by 75% of more of the respondents. The profiles of the remaining six diagnostic groups were associated with the corresponding diagnoses by 50% or fewer of the respondents.     

Diagnosis in a psychiatric case register

This study examines the stability of psychiatric diagnosis over a five-year period and its agreement with the diagnosis of a case register. The stability of diagnosis over a period of time has two component parts: the course of the morbid process and the reliability of the diagnostic technique. We studied the importance of these components as far as the cause of disends in diagnostic changes, the discrepancy of instability in different diagnostic categories and factors which may possibly indicate instability of psychiatric diagnosis.     

The reliability of the family history method for psychiatric diagnoses

We evaluated the test-retest interrater reliability of the Family History Research Diagnostic Criteria (FH-RDC) in 58 depressed patients who described 341 first-degree relatives. Reliability was examined as a function of the threshold to determine caseness. In general, diagnostic reliability was good-excellent for specific FH-RDC disorders, but not for the residual category of other psychiatric disorder. A higher diagnostic threshold was associated with greater reliability, especially for the diagnosis of depression. Patient variance accounted for a greater percentage of the disagreements between the interviewers than did rater variance.     

Interrater reliability of neuropsychological diagnoses: a Department of Veterans Affairs cooperative study.

This study examined the interrater reliability of neuropsychological diagnoses produced by clinical neuropsychologists across 4 medical centers. These diagnoses were based on evaluations using a comprehensive battery of commonly used neuropsychological test instruments, interview, history and medical chart review. The diagnoses of individual neuropsychologists were compared to those made by members of an external review panel for each patient evaluated. Patients were first diagnosed as showing cognitive impairment versus no cognitive impairment. If a patient was diagnosed as impaired, a specific neuropsychological diagnosis was assigned. The diagnostic classification for cognitive impairment was moderately reliable [kappa = .48 +/- s.e.(kappa) = .062]. The interrater reliability for specific diagnoses was in the fair to good range [kappa = .44 +/- s.e.(kappa) = .029]. These levels of reliability are comparable to those found for other psychiatric and neurologic specialties and for medical diagnoses made by other health care disciplines.     

Multiple sclerosis and birth order: a longitudinal cohort study

BACKGROUND: Genetic epidemiological studies suggest both genetic and environmental factors have a role in multiple sclerosis (MS). Environmental effects are strongly suggested from geographical gradients, migration data, and discordance rates in twins. In epidemiological studies, risk of MS in offspring of small families and in those with an early birth-order position has been reported and interpreted in the context of the hygiene hypothesis, which is that infections at an early age, introduced by older siblings, are protective. We aimed to study the effect of birth order on MS risk. METHODS: A longitudinal, population-based sample of individuals with MS and their healthy siblings were identified from the Canadian Collaborative Project on Genetic Susceptibility to MS. Data were grouped according to single (simplex) or multiple (multiplex) siblings with MS in a sibship. Separate analyses were done for each sibship size. FINDINGS: We studied 10 995 individuals with MS and 26 336 healthy siblings, and found no relation between MS risk and birth-order position. In simplex sibships of at least seven siblings, slightly more siblings who were born late in the birth order had MS; the same was found for the first-born sibling with MS in a multiplex sibship. Siblings with MS were slightly younger (p<0.0001) than those without MS, contrary to the expected age at onset bias. INTERPRETATION: These findings do not support the hygiene hypothesis and could be due to a cohort effect resulting from increasing MS incidence. Birth order has no effect on MS risk in most families, and there is no support for the hypothesis that having older siblings protects against MS.     

The psychiatrist factor in case register data interpretation

Summary Data in the Aberdeen Psychiatric Case Register on all consecutive new referrals to two selected psychiatrists during a two year period have been studied to provide an index of the influences of psychiatric orientation on diagnostic usage, patient disposal and treatment recommendations. The object of the study was to show that data subscribed by psychiatrists of different orientation differed because of their orientation and that interpretation of register reporting properly should take account of this.The psychiatrists were selected for their considerable similarities; they differed essentially only in orientation, one using the analytical model, the other using the eclectic model. The referrals who consulted each were randomly allocated from all new referrals to the regional psychiatric service. The two series were socially and demographically similar except in respect of marital status and social class distributions but these factors did not affect the differences in diagnostic usage, patient disposal and treatment choice recorded. The analytically-oriented psychiatrist favoured diagnoses of personality disorders, recommended the majority of his patients for outpatient treatment and prominently used intensive psychotherapeutic methods. The eclectic psychiatrist favoured diagnoses of neurotic illness, advised the referral agent on management of as many patients as were recommended for outpatient treatment and prominently used supportive regimes and physical methods.It is suggested that these variations reflect psychiatric orientation rather than differences in patient characteristics.The relevance of this to interpretation of case register data is discussed.

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Zusammenfassung Während einer zweijährigen Zeitstrecke wurden die Fall-Register-Daten zweier Psychiater aus Aberdeen miteinander verglichen; und zwar wurden alle Erstüberweisungen berücksichtigt. Man wollte auf diese Weise den Einfluß der allgemeinen Orientierung des Psychiaters auf die Diagnostik und Behandlungsempfehlungen kennenlernen. Es wurde die Annahme gemacht, daß die unterschiedliche Orientierung der Psychiater zu unterschiedlichen Ausgangsdaten ihrer Dokumentation führt und daß diese Unterschiede in der Bewertung der psychiatrischen Fall-Register berücksichtigt werden müssen.Die beiden ausgewählten Psychiater unterschieden sich bei Gleichartigkeit aller sonstigen Dimensionen in ihrer professionellen Orientierung darin, daß der eine das analytische Modell, der andere ein eklektisches Modell benutzte. Die bearbeiteten Erstüberweisungen wurden nach einer Zufallsverteilung aus allen Erstüberweisungen der regionalen psychiatrischen Dienste ausgewählt. Die beiden Patienten-Serien waren in sozialer und demographischer Hinsicht miteinander vergleichbar und unterschieden sich lediglich im Hinblick auf den Anteil Verheirateter und die Verteilung auf die Sozialklassen. Die letztgenannten Faktoren beeinflußten indessen die diagnostischen und therapeutischen Unterschiede beider Psychiater nicht. Der analytisch orientierte Psychiater bevorzugte die Diagnosen der Persönlichkeitsstörungen, empfahl die Mehrzahl seiner Patienten für eine ambulante Behandlung und benutzte vorwiegend die Methoden einer intensiven Psychotherapie. Der eklektisch orientierte Psychiater stellte häufiger Diagnosen aus dem neurotischen Formenkreis, und riet der Hälfte seiner Patienten, nach der ersten Konsultation die Arbeit wieder aufzunehmen, der anderen Hälfte zur ambulanten Weiterführung der Behandlung; therapeutisch bevorzugte er unterstützende Beratung und körperliche Behandlungsmethoden.Die Daten lassen den Schluß zu, daß solche Unterschiede mit der unterschiedlichen Orientierung der Psychiater zusammenhängen und nicht mit Eigentümlichkeiten der Patienten.

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Résumé Pendant deux ans, deux psychiatres choisis pour leur différence d'orientation inscrirent les données concernant tous les consultants dans le registre psychiatrique d'Aberdeen. Ces données servirent à établir un index de l'influence d'orientation psychiatrique sur le diagnostic, la façon d'agir envers le patient et le traitement recommandé. Le but de cette étude était de montrer que les différences existaient à cause de l'orientation différente et que, par conséquent, l'interprétation des notes enregistrées devait en tenir compte.Les psychiatres furent choisis pour leurs similitudes considérables; ils ne différaient essentiellement que dans leur orientation, l'un utilisant la méthode analytique, l'autre la méthode éclectique. Les patients qui les consultaient leur étaient adressés sans distinction depuis le service psychiatrique régional. Les deux séries étaient semblables socialement et démographiquement et ne pouvaient différer qu'en ce qui concerne l'état civil et l'appartenance à une classe sociale, facteurs n'infuençant pas les différences de diagnostic, de contact et de traitement. Le psychiatre d'orientation analytique choisissait des diagnostics touchant aux troubles de la personnalité, faisait suivre la majorité de ses patients ambulatoirement et utilisait des méthodes psychothérapeutiques de façon intensive. L'autre psychiatre préférait des diagnostics d'affections névrotiques, demandait que tous ses patients soient suivis ambulatoirement et préconisait des méthodes de soutien et des traitements biologiques.Il est suggéré que ces variations reflètent davantage l'orientation des psychiatres que des différences chez les patients.La pertinence de cette interprétation des données du registre est discutée.

     

Reported prevalence of alcohol dependence in South-Verona: a case register study

In this study all patients who received from 1979 to 1982 the diagnosis of “alcohol dependence” have been selected from the South-Verona Psychiatric Case Register. The register area coincides with the health care area of a well-integrated community psychiatric Service, set up in 1978 under the new Italian Mental Health Act. The reported prevalence rates of alcoholic patients decreased in this 4-year period, this decrease being due mainly to the diminuition of male patients contacting a psychiatric agency. Age- and sex-specific prevalence rates are reported, as are patterns of inpatient and out-patient care and 1-year inception rates. Within the overall reported prevalence the ratio between patients who received community care only and those who had also or only inpatient care shows that about half of alcoholic patients contacting a psychiatric agency receive out-patient care only.