INTRODUCTION

The diagnosis of MS has far-reaching consequences in the lives of those affected and their relatives. It should therefore be made on the basis of rational and sound consideration. The description of the diagnosis by a leading MS researcher may well be accurate: “Multiple sclerosis is what a good clinician would call multiple sclerosis” (Kurtzke 1974). However, the physician who is confronted with a patient and his or her symptoms needs diagnostic criteria based on numerous reliable principles in order to establish a diagnosis. Rationally proven clinical diagnosis facilitates the discussion with patients and their relatives and allows for a more clearcut differential diagnosis. Various clinical studies – be they concerned with the course of the disease, with epidemiological problems, or with the use of therapeutic interventions – may be more easily compared if they incorporate a unified diagnostic terminology. A correct diagnosis may be made earlier if strict diagnostic criteria are applied (Izquierdo et al. 1985).

DIAGNOSTIC CRITERIA

The diagnostic criteria of MS have been in use for decades (Schumacher et al. 1965; McDonald and Halliday 1977). The diagnosis was usually based almost exclusively on the clinical history and on neurological examinations made during the course of the disease. The lists of diagnostic criteria were constructed mainly in order to compare clinical therapeutic studies.