Classification of mental disorder in primary care.

This monograph describes a study designed to test how far the two major international systems of disease classification, International Classification of Diseases (ICD) and International Classification of Health Problems in Primary Care (ICHPPC), can be consistently applied by General Practitioners (GPs) to mental disorder presenting in primary care, and to identify sources of observer variation occurring at different stages of clinical judgement. A group of 27 senior GPs was exposed to a series of real life general practice consultations, either in the form of videotape or written case-vignette material, chosen to reflect a wide range of minor psychiatric problems, differing not only in respect of phenomenology but also of their associations with social stresses and supports, physical illness and personality features. The findings clearly indicate that neither ICD nor ICHPPC can be applied consistently by GPs. However, while the overall diagnostic concordance using ICD and ICHPPC proved to be disappointingly low, agreement on individual observations relating to psychological, physical, personality and social features was moderately good. It was also noted that participants, when given the opportunity, tended to incorporate several domains into their diagnostic conclusions, aiming for a multidimensional formulation, to which neither ICD nor ICHPPC lend themselves. It is, therefore, not surprising that if the principal diagnostic schemata are neither adequate in themselves nor readily applicable to primary care, then GPs are more likely to resort to symptomatic treatment and evade diagnosis when confronted with minor psychiatric morbidity. The consequence of this approach for National Morbidity Surveys and drug trials are discussed. The historical development of multiaxial schemata of classification is briefly traced, the problems associated with DSM-III are discussed, and a comprehensive model of classification is proposed which incorporates the notions of severity and duration as well as of category on the four dimensions of psychological illness, social stresses and supports, personality and physical illness.