Quantitation of hemoglobin F. An interlaboratory study.

Area of Science:

• Hematology
• Clinical Chemistry

Background:

• Accurate quantitation of fetal hemoglobin (Hb F) is crucial for diagnosing and managing hemoglobinopathies.
• Previous assessments of Hb F measurement accuracy and variability were limited.

Purpose of the Study:

• To evaluate the interlaboratory variability and accuracy of methods used for quantitating hemoglobin F (Hb F).
• To assess the performance of laboratories in the 1976 and 1977 Center for Disease Control (CDC) hemoglobinopathy proficiency testing surveys.

Main Methods:

• Whole blood samples from normal adults and individuals with elevated Hb F were distributed to over 100 participating laboratories.
• Results were compared against those from 21 designated reference laboratories.
• Data from the 1976 and 1977 CDC hemoglobinopathy proficiency testing surveys were analyzed.

Main Results:

• Significant interlaboratory variability was observed in Hb F quantitation across different methods.
• Most participating laboratories reported results outside two standard deviations of the reference laboratory mean.
• The accuracy of the methods was insufficient to reliably differentiate between normal and elevated Hb F levels.

Conclusions:

• Current methods for Hb F quantitation demonstrated poor accuracy and high variability among laboratories.
• Proficiency testing revealed a critical need for standardization and improvement in Hb F measurement techniques.
• The observed inaccuracies could lead to misdiagnosis or inadequate management of hemoglobinopathies.