Annual proficiency surveys were conducted three times a year (2020–2021) by the Korean Association of External Quality Assessment Services. In addition to the image samples (MPI-20-01–MPI-20-04 and MPI-21-01–MPI-21-05), the pre-made slide samples (MPS-20-01–MPS-20-05 and MPS-21-01, MPS-21-02) and the formalin samples (MPF-21-01 and MPF-21-02) were included. Even though the image samples were not usually found recently, they were prepared to target parasites that were clinically or epidemiologically important in Korea. The overall agreement rates were 97.7% in 2020 (participant laboratories numbers 214–216) and 98.2% in 2021 (participant laboratories numbers 211–213). The agreement rates were significantly lower for the MPS samples than for the MPI samples (MPS 96.6% vs. MPI 99.1%, P=0.0002) in 2020. The agreement rates were significantly lower for the MPF samples than for the MPI or MPS samples (MPF 96.0% vs. MPI 98.9% or MPS 98.6%; P=0.0007 or P=0.0207, respectively) in 2021. Based on our in-depth survey of clinical parasitology, it should be accompanied by continuous education about different parasitic infections, which could aid in overcoming the lack of experience in clinical laboratory inspections.

Keywords: Quality control, Parasitology, Formalin-fixed specimen