We often go to the doctor because of some joint pain, and after a positive rheumatoid factor test, some people will worry if they have rheumatoid arthritis, the answer is no. The answer is no. Rheumatoid factor is an antibody produced in the body due to infectious agents such as bacteria and viruses that use denatured IgG (an antibody) as the antigen, so it is also called anti-antibody. The common rheumatoid factors are IgM, IgG, IgA and IgE. The current clinical test is for IgM rheumatoid factor. Rheumatoid factors are commonly found in the human body and play certain physiological roles, such as mediating immunity, clearing infections, and removing circulating immune complexes in the body. When the amount of rheumatoid factor exceeds a certain titer, it is called rheumatoid factor positive. The normal range of rheumatoid factor is 0-20 IU/ml. even if the rheumatoid factor is positive, it is not certain to be rheumatoid arthritis. Especially if the rheumatoid factor titer is not high, it has no definite diagnostic value. Certain autoimmune diseases, such as cryoglobulinemia, progressive systemic sclerosis, dry syndrome, and systemic lupus erythematosus have a high positive rate in patients; some other diseases such as vasculitis, liver disease, and chronic infections can also have a positive RF. The diagnosis of rheumatoid arthritis should be combined with relevant clinical symptoms, laboratory tests and imaging examinations for comprehensive judgment. If there is symmetrical small joint pain, swelling with morning stiffness, significantly increased blood sedimentation, positive rheumatoid factor, and bone erosion on joint x-ray, one needs to be highly alert to rheumatoid arthritis and go to a specialist for consultation and treatment as early as possible. With early diagnosis, combined medication, and functional exercise, rheumatoid arthritis can be completely relieved.