A follow‐up statistical analysis of the 1971 College of American Pathologists Comprehensive Blood Bank Survey was made to determine if the variability of blood bank reagents noted in the 1970 Survey had significantly changed between 1970 and 1971. These studies revealed discordant results only in sera used to detect B‐positive and A1‐negative red cells. No significant differences were found in any of the Rh typing sera. However, there was significant improvement from 1970 to 1971 in all manufacturers' sera as measured by this m