Can two labs get different results when testing the same blood? And if so: can these differences be large?

Answer

Dear Jean,

Blood tests by two different laboratories must give the same result in the sense that abnormal results in one lab must also be abnormal (that is, outside the ‘normal’ values) in the other lab.

However, when you look at absolute numbers, there can be differences between two different laboratories. This is because they may work with different equipment or reagents or because they will report the relevant parameter (eg protein or glucose) in a different unit. However, by working with the appropriate normal values ​​or reference values, the final decision must be the same, ie too high or too low compared to the standard.

If the requesting doctor has doubts about the correctness of one of the two results, he can always contact both laboratories to see if there has been an error somewhere.

Regards,

Dr. Glenn Van den Bosch