Causes of DIsCrepant HemoglobIn results
At LifeLabs, we occasionally receive calls regarding discrepant hemoglobin results. The motivation for the call is often that our reported hemoglobin value is lower than that of another laboratory. Frequently the patient is transferred to a hospital setting for a red cell transfusion that is later cancelled because of a higher repeat hemoglobin result. This is understandably frustrating and inconvenient for the patient, their family, and medical staff.
We value this feedback and investigate these inquiries thoroughly. Often, after careful review of our laboratory performance, we are unable to find a root cause. While this could mean the other laboratory hemoglobin value is inaccurate, it is more likely that both laboratories are analytically correct and that the discordant values are the work of unavoidable factors causing variation in results.
Regarding laboratory values, a certain amount of variation is allowable and expected. Specifically with regard to hemoglobin values, there are several sources of variability that can account for discordant results: