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Clinical Chemistry and Laboratory Medicine (CCLM)

Published in Association with the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM)

Editor-in-Chief: Plebani, Mario

Ed. by Gillery, Philippe / Lackner, Karl J. / Lippi, Giuseppe / Melichar, Bohuslav / Payne, Deborah A. / Schlattmann, Peter / Tate, Jillian R.

12 Issues per year


IMPACT FACTOR 2016: 3.432

CiteScore 2016: 2.21

SCImago Journal Rank (SJR) 2016: 1.000
Source Normalized Impact per Paper (SNIP) 2016: 1.112

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1437-4331
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Volume 43, Issue 11 (Nov 2005)

Issues

Mean and variance quality control for multiple correlated levels of replicated control samples

John H. Livesey
  • Endolab, Christchurch Hospital, Christchurch, New Zealand
Published Online: 2011-09-21 | DOI: https://doi.org/10.1515/CCLM.2005.215

Abstract

Mean and variance rules for quality control are more powerful than rules based on individual values. An algorithm for applying such rules is described that controls type I errors (false alarms), while allowing for multiple levels of quality control samples, correlation between levels, small numbers of preliminary values, replication of samples and autocorrelation arising from random effects. Based on ANOVA and empirical approximations for small samples, the algorithm maintains a low per-batch probability of type I errors. Three statistics are computed, zm, zb and zw, which are shown by simulations to be primarily sensitive to a concordant shift in the quality control values, a discordant shift in the values, and an increase in random variability, respectively. Simulations also show that for a Gaussian distribution of analytical errors, the per-batch probability of a type I error is likely to be within the range 0.0045–0.0071 for two to four levels where there are 20–100 preliminary batches and the inter-level correlations are between zero and 0.8. This partial separation of out-of-control alarms into three components provides more assistance with trouble-shooting than do multivariate quality control schemes based on Hotelling's T2, while retaining comparable power.

Keywords: biometry; clinical chemistry; laboratory techniques and procedures; quality control

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About the article

Corresponding author: John H. Livesey, Endolab, Christchurch Hospital, Private Bag 4710, Christchurch, New Zealand Fax: +64-3-3640818,


Received: 2005-04-14

Accepted: 2005-08-18

Published Online: 2011-09-21

Published in Print: 2005-11-01


Citation Information: Clinical Chemistry and Laboratory Medicine (CCLM), ISSN (Online) 1437-4331, ISSN (Print) 1434-6621, DOI: https://doi.org/10.1515/CCLM.2005.215.

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©2005 by Walter de Gruyter Berlin New York. Copyright Clearance Center

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