In 2021, external quality assessment trials for urinalysis and fecal occult blood (FOB) testing were conducted using data from 1,728 and 714 participants respectively. Urine chemistry tests were performed three times, and urine sediment and FOB tests were performed twice. Urine chemistry tests consisted of pH, protein, glucose, ketone bodies, bilirubin, blood, urobilinogen, nitrite, leukocyte, and specific gravity analyses. The results of urine chemistry and specific gravity tests showed acceptable rates of >95%, except for the pH, protein, bilirubin and urobilinogen tests. The instruments that showed <80% acceptable rates in pH, protein, or bilirubin tests were Simens (12 times), Beckman (7 times), and Eiken (4 times). Urine sediment test showed acceptable rates of <80% for uric acid crystals and waxy cast, but satisfactory results for transitional epithelial cells, ammonium magnesium phosphate, and calcium phosphate crystals. In the FOB qualitative test, four reagents showed acceptable rates of <90% for negative samples, indicating the possibility of false positives. In the FOB quantitative test, the results of positive samples differed from company to company, so standardization of the test method was required.

Keywords: Quality control, Urinalysis, Occult blood, Accuracy