<unk>  or<unk>  is a test performed before a blood transfusion as part of blood compatibility testing. Normally, this involves adding the recipient's blood plasma to a sample of the donor's red blood cells. If the blood is incompatible, the antibodies in the recipient's plasma will bind to antigens on the donor red blood cells. This antibody-antigen reaction can be detected through visible clumping or destruction of the red blood cells, or by reaction with anti-human globulin. Along with blood typing of the donor and recipient and screening for unexpected blood group antibodies,<unk>  is one of a series of steps in pre-transfusion testing. In some circumstances, an electronic<unk> -match can be performed by comparing records of the recipient's ABO and Rh blood type against that of the donor sample. In emergencies, blood may be issued before<unk>  is complete.<unk>  is also used to determine compatibility between a donor and recipient in organ transplantation.
Cross-matching
Chemosensitivity assay
Seroprevalence
Transmission disequilibrium test
Genetic linkage
Flow cytometry
Genetic discrimination
Allergy test