Background
Genotyping for red blood cell (RBC), platelet and granulocyte antigens is a new tool for clinical pathology, transfusion medicine services and blood banks. Proficiency in laboratory tests can be established by external quality assessments (EQAs), which are required for clinical application in many health care systems. There are few EQAs for molecular immunohematology.
Methods
We analyzed the participation and pass rates in an EQA for RBC, platelet and granulocyte antigens. This EQA was distributed by INSTAND, a large non-profit provider of proficiency tests, twice per year since fall 2006 as EQA no. 235 Immunohematology A (molecular diagnostic). The coordinators defined at the outset which alleles are mandatory for detection.
Results
The number of participants steadily increased from 51 to 73 per proficiency by fall 2012. More than 60 institutions utilized this EQA at least once a year. Approximately 80% of them participated in RBC, 68% in platelet and 22% in granulocyte systems. With the exceptions of RHD (82%) and granulocytes (85%), pass rates exceeded 93%. While the pass rate increased for granulocyte and decreased for the ABO system, the pass rates for the other systems changed little over 6 ½ years.
Conclusions
The INSTAND proficiency test program was regularly used for EQA by many institutions, particularly in Central Europe. While the technical standards and pass rates in the participating laboratories were high, there has been little improvement in pass rates since 2006.