Lab Med Online.  2018 Jan;8(1):19-23. 10.3343/lmo.2018.8.1.19.

Internal Quality Assurance Status of Stool Examination as Assessed by a Questionnaire in Korean Clinical Laboratories

  • 1Department of Laboratory Medicine, Chonnam National University Medical School, Gwangju, Korea.


This study aimed to survey the status of quality control (QC) assurance for stool examinations at clinical laboratories in Korea. We sent a questionnaire related to QC practices in stool examination by electronic mail to Korean clinical laboratories that performed stool examination. Overall, 20 of the 39 laboratories (51.3%) reported performing stool concentration methods, and 28 (71.8%) examined the slides using only saline. A large proportion (74.4%) of respondents did not check the internal QC because of the restriction of appropriate control materials. Only four laboratories (10.3%) checked the reactivity of the dye solution routinely. For appropriate external QC systems, QC slides (43.6%) were preferred, followed by QC materials (30.8%), virtual slides (17.9%), and a combination of the above options (7.7%). The most commonly observed parasites in stool samples at the clinical laboratories were Clonorchis sinensis (75%), followed by Endolimax nana, Enterobius vermicularis, and Entamoeba coli. The present study describes the difficulties in internal QC assessment due to the absence of standardized QC materials and systems. We hope the findings of this report will provide a foundation for a QC assessment program for stool examinations in the near future.


Stool examination; Quality control; Survey

MeSH Terms

Clonorchis sinensis
Electronic Mail
Quality Control
Surveys and Questionnaires


  • Fig. 1. The most commonly observed (A) and the second-most commonly observed (B) parasites during stool examinations in Korean clinical laboratories participating in this study.


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