a blood test in which a sample of serum is exposed to a particular antigen and complement in order to determine whether or not antibodies to that particular antigen are present; used as a diagnostic test
The complement fixation test is an immunological medical test that can be used to detect the presence of either specific antibody or specific antigen in a patient's serum. It was widely used to diagnose infections, particularly with microbes that are not easily detected by culture methods, and in rheumatic diseases.