Chapter V (F) of ICD-10: mental, behavioural and developmental disorders--introduction and overview.

The need for precise psychiatric diagnoses is indisputable, both for cooperation within the health service systems and for scientific purposes. Over the last few years there has been a revival of interest in psychiatric nosology. Despite new strategies and the results of numerous individual research efforts, no uniform and general satisfactory theory, and thus no classification of mental disorders, has been developed. After the Second World War, the WHO succeeded in introducing an internationally accepted diagnostic system, the ICD-classification. In 1980 the American Psychiatric Association (APA) introduced its DSM-III classification with explicit diagnostic criteria and rules. The ICD-10 has been in preparation since 1982, and will differ considerably from ICD-9: An alpha-numerical system of coding expands the possibilities for diagnoses. For the first time in the history of ICD operational diagnostic criteria and rules are being introduced. The new structure will permit adjustments without the need to completely change the entire classification. The WHO division of mental health is preparing a range of documents and instruments for various purposes; clinical descriptions and diagnostic guidelines for daily clinical use, a short version and the more detailed research criteria; a multiaxial coding is planned as well. The classification of the mental disorders is based on etiological considerations, as far as these are known, in particular in the case of organic disorders, disorders due to the use of psychoactive substances, and stress-related disorders. In other areas, a more non-theoretical and descriptive approach was chosen. As a major change the large "blocks" psychoses and neuroses have been abandoned.(ABSTRACT TRUNCATED AT 250 WORDS)