The comprehensive blood bank survey program of the College of American Pathologists, 1974.

Results of the 1974 College of American Pathologists Comprehensive Blood Bank Survey Program show that ABO and Rh typing are still holding their percentage of excellent (99.48%) accuracy. At least some of the errors still occurring are due to clerical mistakes in filling out the forms and not to technical inaccuracy. Antibody detection shows good accuracy but varies, depending on the complexity of the problems--the easier the problem the higher the rate of concurrence, while the more complex the problem the more variance in results. Crossmatching accuracy is 99% correct or better on any but the most complex problems. Some of the problems involving interpretation of autoimmune hemolytic anemia are discussed.