[Classical special investigations in hospital neurology. Evaluation of their diagnostic contribution (author's transl)].

A quantitative analysis of the diagnostic contribution of the classical special investigation normally used in hospital neurology. Six examinations were studied: laboratory blood investigations, electroencephalogramm, lumbar puncture, optic fundus, standard skull X-ray, standard spine X-ray. The analysis involved 548 patients in whom 2219 examinations were performed with a yield of 26 "corrected" diagnosis (a diagnosis in which there was a clinical error corrected in the light of the results of these examinations).