In Korea, external quality assessment trials for urinalysis and faecal occult blood (FOB) were performed for 1,250 participants. Urine chemistry and FOB tests were evaluated three times, whereas urine sediment by photography was evaluated twice. Urine chemistry tests consisted those for pH, protein, glucose, ketone, bilirubin, blood, urobilinogen, nitrite, leukocyte, and specific gravity. The results of the urine chemistry and specific gravity tests showed accuracy rates >95%. In the FOB quality test, all reagents showed false-positive results. These reagents showed positive results in stool specimens containing >11 ng/mL haemoglobin. In the FOB quantitative test, the results were significantly different, based on the instrument used for the measurements. The average accuracy rate of urine sediments was 90.8%, whereas those for renal epithelial cells and cholesterol crystals were 83%.

Keywords: Quality assessment, Urinalysis, Occult blood

1. Jeon CH, Lee AJ, Kim KD; The Urinalysis & Routine Microscopy Subcommittee, Korean Association of External Quality Assessment Service. Annual report on external quality assessment scheme for urinalysis and faecal occult blood testing in Korea (2014). J Lab Med Qual Assur 2015;37:179-89.
   
2. Guittet L, Bouvier V, Mariotte N, Vallee JP, Levillain R, Tichet J, et al. Performance of immunochemical faecal occult blood test in colorectal cancer screening in average-risk population according to positivity threshold and number of samples. Int J Cancer 2009;125:1127-33.
   
3. Levi Z, Rozen P, Hazazi R, Vilkin A, Waked A, Maoz E, et al. A quantitative immunochemical fecal occult blood test for colorectal neoplasia. Ann Intern Med 2007;146:244- 55.
   
4. Park DI, Ryu S, Kim YH, Lee SH, Lee CK, Eun CS, et al. Comparison of guaiac-based and quantitative immunochemical fecal occult blood testing in a population at average risk undergoing colorectal cancer screening. Am J Gastroenterol 2010;105:2017-25.
   
5. Brenner H, Tao S. Superior diagnostic performance of faecal immunochemical tests for haemoglobin in a headto-head comparison with guaiac based faecal occult blood test among 2235 participants of screening colonoscopy. Eur J Cancer 2013;49:3049-54.
   
6. Kim JH, Hwang SY, Kim YJ. Evaluation of Hemo Techt NS-plus C15 Automatic Analyzer for fecal occult blood test. J Lab Med Qual Assur 2010;32:237-41.
7. McPherson RA, Pincus MR. Henry’s clinical diagnosis and management by laboratory methods. 23rd ed. St. Louis (MO): Elsevier, 2017:461-71.