摘要: Early diagnosis of rheumatoid arthritis (RA) is an important challenge for clinical rheumatologists. This because there substantial evidence that early treatment with disease-modifying antirheumatic drugs leads to a better disease outcome. The 1987 American College Rheumatology classification criteria RA do not perform well as diagnostic tool in arthritis. Therefore, studies are needed develop or prediction models enable clinicians distinguish from other arthritides phase the disease. Diagnostic hampered by lack independent gold standard RA. Since most features persistence and development erosions, outcome clinically relevant standard. Diagnosis phased, multivariable process which probability presence updated continuously when new information added patient profile. besides univariate studies, evaluate value current practice procedure. chapter describes multivariate have been performed populations assess medical history, physical examination, laboratory tests imaging diagnosis.