An 18-Year Review of Hemoglobinopathy Proficiency Testing: Recommendations From the College of American Pathologists Hematology and Clinical Microscopy Committee.

Abstract

Context.—: The College of American Pathologists Hematology and Clinical Microscopy Committee implemented a hemoglobinopathy proficiency testing and education program to monitor and assess the performance of participating laboratories.

Objective.—: To evaluate the performance of clinical laboratories for hemoglobinopathy proficiency testing from 2005 to 2023.

Design.—: The hemoglobinopathy challenges are composed of clinical case summaries and electrophoretic and chromatographic gel and tracing images. The participants are asked to determine (1) what hemoglobin chain is affected and (2) the hemoglobinopathy diagnosis.

Results.—: A total of 365 to 676 laboratories were enrolled in the proficiency testing program each year. Overall, the error rates for determination of the affected globin chain and a hemoglobinopathy diagnosis ranged from 0.6% to 56.5% and 0.5% to 86.5%, respectively. Twenty-three of 66 surveyed hemoglobinopathies (34.8%) had an error rate exceeding the consensus threshold of 20%. The globin gene detection error rate of the compound hemoglobinopathies was significantly higher when compared with just the α (P = .01) and β (P = .003) gene disorders. However, the error rate for the overall compound α/β-globin interpretation, although high at 23%, was not statistically significant when compared with just the α- or β-globin chain disorders. In repeat testing of the variants, there was no consistent improvement in performance.

Conclusions.—: The program participants demonstrated variable performance with one-third of the surveys exceeding the 20% error rate. The error rate for compound hemoglobinopathies was even higher. Our data illustrate a critical need for continuing educational efforts with an algorithmic approach to hemoglobin disorders.