serum immunoglobulin G-type rheumatoid factor level relative to an arbitrary reference serum 2014-01-27T13:21:41Z A calculated measurement of the amount in a specified sample of serum of rheumatoid factor that is expressed as an immunoglobulin G (IgG) molecule in which the level of antibody is normalized to an arbitrary reference value or reference standard. Rheumatoid factor (RF) is an autoantibody against the Fc portion of IgG found in rheumatoid arthritis and some other autoimmune diseases. RF and IgG join to form immune complexes that contribute to the disease process. CMO:0002112 JSmith clinical_measurement_ontology serum IgG-RF level normalized to an arbitrary reference level serum IgG-rheumatoid factor level normalized to an arbitrary reference level serum immunoglobulin G-type rheumatoid factor level