I am not sure what more information you would need. Here is a brief synopsis of errors I have witnessed or been informed of:
We have had wrong types entered. On multiple occasions. We have a vision so we should have it interfaced, but we had enter. We have a large volume of T/S per day. Between 75-125 depending on the day.
We have had a Positive antibody screen entered as Negative and an IS XM performed when it was later found (on the same specimen, and totally by accident) that the patient had an anti-E. Luckily when checking the two units that were transfused were negative for E.
We have a specimens mislabeled. Which leads to WBIT (Wrong blood in tube) and without a typecheck these cannot be caught. And an serological (IS) will not pick these ups. This, to me, seems to be the biggest issue.
I was just curious. This is a fairly new hospital I am working at and everywhere else we had a Typecheck system and instrument interfacing to help prevent these very preventable errors.