Ann Lab Med.  2017 May;37(3):213-222. 10.3343/alm.2017.37.3.213.

Effect of Accreditation on Accuracy of Diagnostic Tests in Medical Laboratories

• Jang MA
• Yoon YA
• Song J
• Kim JH
• Min WK
• Lee JS
• Lee YW
• Lee YK

• KMID: 2369746
• DOI: http://doi.org/10.3343/alm.2017.37.3.213

Abstract

BACKGROUND
Medical laboratories play a central role in health care. Many laboratories are taking a more focused and stringent approach to quality system management. In Korea, laboratory standardization efforts undertaken by the Korean Laboratory Accreditation Program (KLAP) and the Korean External Quality Assessment Scheme (KEQAS) may have facilitated an improvement in laboratory performance, but there are no fundamental studies demonstrating that laboratory standardization is effective. We analyzed the results of the KEQAS to identify significant differences between laboratories with or without KLAP and to determine the impact of laboratory standardization on the accuracy of diagnostic tests.
METHODS
We analyzed KEQAS participant data on clinical chemistry tests such as albumin, ALT, AST, and glucose from 2010 to 2013. As a statistical parameter to assess performance bias between laboratories, we compared 4-yr variance index score (VIS) between the two groups with or without KLAP.
RESULTS
Compared with the group without KLAP, the group with KLAP exhibited significantly lower geometric means of 4-yr VIS for all clinical chemistry tests (P<0.0001); this difference justified a high level of confidence in standardized services provided by accredited laboratories. Confidence intervals for the mean of each test in the two groups (accredited and non-accredited) did not overlap, suggesting that the means of the groups are significantly different.
CONCLUSIONS
These results confirmed that practice standardization is strongly associated with the accuracy of test results. Our study emphasizes the necessity of establishing a system for standardization of diagnostic testing.

Keyword

The Korean Association of External Quality Assessment Service; The Korean External Quality Assessment Scheme; Quality assurance; Quality system management; Standardization; Accuracy

MeSH Terms

Accreditation*
Bias (Epidemiology)
Clinical Chemistry Tests
Delivery of Health Care
Diagnostic Tests, Routine*
Glucose
Korea
Glucose

Figure

• 

  Fig. 1 Comparison of geometric means of the variance index score (VIS) for clinical chemistry tests between laboratories with or without KLAP in 2013. The 95% confidence intervals for the mean of each test in the two groups did not overlap. (A) VIS<50 and (B) VIS: 50–100. The graph shows the clinical chemistry tests on the X-axis and the geometric means of the VIS on the Y-axis.Abbreviations: BUN, blood urea nitrogen; KLAP, Korean Laboratory Accreditation Program; γ-GT, γ-glutamyl transferase; VIS, variance index score.

Reference

1. Forsman RW. Why is the laboratory an afterthought for managed care organizations? Clin Chem. 1996; 42:813–816. PMID: 8653920.

2. Burnett D. ISO 15189:2003--quality management, evaluation and continual improvement. Clin Chem Lab Med. 2006; 44:733–739. PMID: 16729862.

3. McPherson RA, Pincus MR, editors. Henry's clinical diagnosis and management by laboratory methods. 23th ed. St. Louis, MO: Elsevier;2017. p. 2–5.

4. Medicare, Medicaid and CLIA programs; regulations implementing the Clinical Laboratory Improvement Amendments of 1988 (CLIA)--HCFA. Final rule with comment period. Fed Regist. 1992; 57:7002–7186. PMID: 10170937.

5. Cho HI. Twenty-years of experiences in external quality assurance in Korea. Southeast Asian J Trop Med Public Health. 1999; 30(S3):32–38.

6. Shin BM, Chae SL, Min WK, Lee WG, Lim YA, Lee DH, et al. The implementation and effects of a clinical laboratory accreditation program in Korea from 1999 to 2006. Korean J Lab Med. 2009; 29:163–170. PMID: 19411785.

7. Jun SH, Song J. Annual Report on the External Quality Assessment Scheme in Clinical Chemistry in Korea (2013). J Lab Med Qual Assur. 2014; 36:113–121.

8. Whitehead TP, Woodford FP. External quality assessment of clinical laboratories in the United Kingdom. J Clin Pathol. 1981; 34:947–957. PMID: 7024326.

9. Huisman W, Horvath AR, Burnett D, Blaton V, Czikkely R, Jansen RT, et al. Accreditation of medical laboratories in the European Union. Clin Chem Lab Med. 2007; 45:268–275. PMID: 17311523.

10. Guzel O, Guner EI. ISO 15189 accreditation: Requirements for quality and competence of medical laboratories, experience of a laboratory I. Clin Biochem. 2009; 42:274–278. PMID: 19863920.

11. Kibet E, Moloo Z, Ojwang PJ, Sayed S, Mbuthia A, Adam RD. Measurement of improvement achieved by participation in international laboratory accreditation in sub-Saharan Africa: the Aga Khan University Hospital Nairobi experience. Am J Clin Pathol. 2014; 141:188–195. PMID: 24436265.

12. Gershy-Damet GM, Rotz P, Cross D, Belabbes el H, Cham F, Ndihokubwayo JB, et al. The World Health Organization African region laboratory accreditation process: improving the quality of laboratory systems in the African region. Am J Clin Pathol. 2010; 134:393–400. PMID: 20716795.

13. Sciacovelli L, Plebani M. The IFCC Working Group on laboratory errors and patient safety. Clin Chim Acta. 2009; 404:79–85. PMID: 19328194.

14. Jamtsho R, Nuchpramool W. Implementation of External Quality Assessment Scheme in clinical chemistry for district laboratories in Bhutan. Indian J Clin Biochem. 2012; 27:300–305. PMID: 26405392.