External Quality Assurance

1 de Verdier C-H Aronsson T Nyberg A . Quality control in clinical chemistry—efforts to find an efficient strategy. Scand J Lab Clin Invest 1984; 44 (suppl 174).

2 Buttner J Borth R Boutwell JH Broughton PMG Bowyer RC Provisional recommendation on quality control in clinical chemistry. Part 5: External quality control. Clin Chem Acta 1979; 98: 129F–145F.

3 Westgard JO Simulation and modelling for optimising quality control and improving analytical quality assurance. Clin Chem 1992; 38: 175–8.

4 US Department of Health and Human Services. Medicare, Medicaid and CLIA Programs: Regulations implementing the clinical laboratory improvement amendments of 1988 (CLIA): Final rule. Fed Regist 1992; 57: 7002–186.

5 Foster HS Probable impact of the 1994 elections on laboratory medicine. Clin Chem 1995; 41: 1223–7.

6 Fraser CG Hyltoft PP Ricos C Haeckel R . Proposed quality specifications for the imprecision and inaccuracy of analytical systems for clinical chemistry. Eur J Clin Chem Clin Biochem 1992; 30: 311–7.

7 Accreditation Handbook, Version 6.4, Standard F1. London: Clinical Pathology Accreditation (UK) Ltd, 1996.

8 Tietz NW Accuracy in clinical chemistry—does anybody care? Clin Chem 1994; 40: 859–61.

9 Schoen J . Excelling in mediocrity. CAP Today 1992; 6: 80.

10 Westgard JO Groth T Aronsson T Falk H de Verdier C-H. Performance characteristics of Rules for Internal Quality Control: Probabilities for false rejection and error detection. Clin Chem 1977; 23: 1857–67.

11 Robert Jenny RW. How good are clinical laboratories? An assessment of current performance. Clin Chem 1992; 38: 1210–7.

12 Buttner J Borth R Boutwell JH Broughton PM Bowyer RC International Federation of Clinical Chemistry Committee on Standards Expert Panel on Nomenclature and Principles of Quality Control in Clinical Chemistry. Approved recommendations (1978) on quality control in clinical chemistry, 1. General principles and terminology. Clin Chem Acta 1979; 98: 129F–143F.

13 Rej R . Proficiency testing, matrix effects and method evaluation. Clin Chem 1994; 40: 345.

14 Westgard JO Barry PL Hunt MR Groth TG A multi-rule Shewhart chart for quality control in clinical chemistry. Clin Chem 1981; 27: 493–501.

15 Westgard JO Charts of operational process specifications (“OPspecs charts”) for assessing the precision, accuracy and quality control needed to satisfy proficiency testing criteria. Clin Chem 1992; 38: 1226–33.

16 Skendzel LP Barnett RN Platt R . Medically useful criteria for analytic performance of laboratory tests. Am J Clin Pathol 1985; 83: 200–5.

17 Fraser CG The application of theoretical goals based on biological variation data in clinical chemistry. Arch Pathol Lab Med 1988; 112: 404–15.

18 Peterson PH Fraser CG Setting quality standards in clinical chemistry: Can competing models based on analytical, biological and clinical outcomes be harmonised? Clin Chem 1994; 40: 1865–8.

19 Westgard JO Seehafer JJ Barry PL Allowable imprecision for laboratory tests based on clinical and analytical test outcome criteria. Clin Chem 1994; 40: 1909–16.

20 Taylor A Briggs RJ External schemes and improvements in the measurement of trace elements in biological fluids. J Analyt Atomic Spectrom 1995; 10: 1033–7.

21 Baldwin D Taylor A . Cross pollination among the EQAS; achieving a single performance index similar to UKEQAS MRVIS, Chap 26. Proceedings of the ACB National Meeting, 1994: London: ACB, 95.

22 Wilson JF Smith BL Toseland PA Williams J Hirst AD Watson ID Horn AN External quality assessment of techniques for the detection of drugs of abuse in urine. Ann Clin Biochem 1994; 31: 335–42.

23 Wilcox R Smith BL Hirst AD Data processing for an external quality assessment scheme for drugs of abuse in urine. Ann Clin Biochem 1988; 25(suppl): 204S.