The use of quantitative measures to analyse the long-term course of RA appears to have provided new insights into the severe morbidity and increased mortality rates of this disease. Quantitative assessment of RA may be viewed as an expression of clinical rheumatology as a quantitative science designed to assess accurately the long-term course of disease. The description of the joint count, radiographic scores, laboratory tests, questionnaire measures and physical measures of functional status, as well as the importance of socio-economic status, may provide new insights into the pathogenesis, prevalence, morbidity and mortality of RA.