Abstract
The limited value of the antiglobulin phase of the crossmatch when a careful antibody screening was performed was demonstrated by analyzing 73,407 compatibility tests for 23,857 patients. By the blood grouping and screening of these patients, 178 cases were detected with unexpected blood group antibodies that were not previously observed. Unexpected antibodies were detected in an additional 13 patients by the saline phase of the crossmatch. The antiglobulin phase disclosed only 1 patient with a very weak anti-Lea and 2 patients whose sera gave doubtful reactions, possibly representing antibodies, but too weak to be identified.