Two trials were conducted with proficiency tests for complete blood cell count (CBC) and blood cell morphology as part of the 2018 Routine Hematology Program of the Korean Association of External Quality Assessment Service. Three different control samples were sent for CBC testing and two blood cell morphology pictures were posted on the laboratory website during each trial. The mean response rates of the 1,719 participating laboratories were 97.4% and 37.2% for CBC and blood cell morphology, respectively. The distribution of equipment for CBC testing was comparable to that of the previous year. The coefficient of variation (CV) ranges were determined as 3.5%–4.1%, 1.9%–2.7%, 1.4%–2.8%, 4.5%–5.3%, and 5.4%–6.9% for white blood cell counts, red blood cell counts, hemoglobin, hematocrit, and platelet counts, respectively. The concordance rate ranged from 83.0% to 97.5% in blood cell morphology tests. We observed a continuous increase in the number of participating laboratories and a trend towards a decrease in the CVs of platelet counts compared to those in 2016. Values of the other assessed parameters were similar to those of the previous year.

Keywords: Laboratory proficiency testing, Blood cell count, Blood cell morphology