Abstract
The repeatability (precision) of clinical pathology results is vital for confidence in the measured values. Comparison to biological variation is an accepted standard for instrument/method performance in human clinical pathology. This study aims to assess precision of biochemistry results from three in-house analyzers and one commercial laboratory analyzer in relation to biological variation and to compare precision between the in-house analyzers and the commercial laboratory analyzer. Two commercially available quality control materials (QCMs) were repeatedly tested on the same and different days. Coefficients of variation were calculated and assessed in relation to published biological variation data for cats and dogs. In-house analyzer results were compared to results from the commercial laboratory. Seven of 13 analytes assessed met desirable quality precision standards for one QCM and minimum quality standards for the other QCM on all analyzers for both cats and dogs. For more than half of all determinations across all in-house analyzers, precision was as good as or better than the commercial laboratory analyzer. The precision of results from the analyzers assessed for most of the analytes tested is generally high, so large differences between repeated results from the same patient are probably due to biological changes rather than analyzer variation.
Similar content being viewed by others
References
Amiri S, Zwanzig S (2011) Assessing the coefficient of variations of chemical data using bootstrap method. J Chemometr 25:295–300. doi:10.1002/cem.1350
Baral RM, Dhand NK, Freeman KP, Krockenberger MB, Govendir M (2014a) Biological variation and reference change values of feline plasma biochemistry analytes. J Feline Med Surg 16:317–325. doi:10.1177/1098612X13508770
Baral RM, Morton JM, Dhand NK, Krockenberger MB, Govendir M (2014b) Bias of feline plasma biochemistry results between three in-house analyzers and a commercial laboratory analyzer: results cannot be directly compared. J Feline Med Surg, in press
Cotlove E, Harris EK, Williams GZ (1970) Biological and analytic components of variation in long-term studies of serum constituents in normal subjects. 3. Physiol Med Implic Clin Chem 16:1028–1032
Doumas BT, Ard Watson W, Biggs HG (1971) Albumin standards and the measurement of serum albumin with bromcresol green. Clin Chim Acta 31:87–96. doi:10.1016/0009-8981(71)90365-2
Flatland B, Freeman KP, Friedrichs KR, Vap LM, Getzy KM, Evans EW, Harr KE (2010) ASVCP quality assurance guidelines: control of general analytical factors in veterinary laboratories. Vet Clin Pathol 39:264–277. doi:10.1111/j.1939-165X.2010.00251.x
Fraser CG (2001) Biological variation: from principles to practice. Amer Assn for Clinical Chemistry, Washington
Fraser CG, Petersen PH (1993) Desirable standards for laboratory tests if they are to fulfill medical needs. Clin Chem 39:1447–1453
Fraser CG, Peake MJ, Cresswell MA (1980) Problems associated with clinical chemistry quality control materials. Crit Rev Clin Lab Sci 12:59–86. doi:10.3109/10408368009108726
Fraser CG, Hyltoft PP, Libeer JC, Ricos C (1997) Proposals for setting generally applicable quality goals solely based on biology. Ann Clin Biochem 34:8–12. doi:10.1177/000456329703400103
Gupta RC, Ma S (1996) Testing the equality of coefficients of variation in k normal populations. Commun Stat-Theor M 25:115–132. doi:10.1080/03610929608831683
Harr KE, Flatland B, Nabity M, Freeman KP (2013) ASVCP guidelines: allowable total error guidelines for biochemistry. Vet Clin Pathol 42:424–436. doi:10.1111/vcp.12101
Harris E (1979) Statistical principles underlying analytic goal-setting in clinical chemistry. Am J Clin Pathol 72:374–382
Jensen AL, Kjelgaard-Hansen M (2006) Method comparison in the clinical laboratory. Vet Clin Pathol 35:276–286. doi:10.1111/j.1939-165X.2006.tb00131.x
Jensen AL, Pedersen HD, Koch J, Aaes H, Flagstad A (1993) Applicability of the critical difference. J Vet Med A 40:624–630. doi:10.1111/j.1439-0442.1993.tb00676.x
Kjelgaard‐Hansen M, Jensen AL, Kristensen AT (2004) Internal quality control of a turbidimetric immunoassay for canine serum C‐reactive protein based on pooled patient samples. Vet Clin Pathol 33:139–144
Klein A, Mischke R (1998) Klinische Prufung des naßchemischen Analysegerätes VetScan beim Hund [Clinical evaluation of the wet chemical analyser, VetScan, in dogs]. Prakt Tierarzt 79:1100–1111
Little C, Gettinby G, Downs J, Marshall C (1992) Consistency of results from the Vettest 8008 clinical biochemistry analyser. Vet Rec 130:419–424. doi:10.1136/vr.130.19.419
Miller WG (2003) Specimen materials, target values and commutability for external quality assessment (proficiency testing) schemes. Clin Chim Acta 327:25–37. doi:10.1016/s0009-8981(02)00370-4
Mischke R, Schossier N, Wirth W (1992) Trockenchemische Blutanalysen bei Hund und Katze mit dem VETTEST 8008 im statistischen Vergleich mit naßchemischen Methoden [Blood testing with dry reagents (VetTest 8008) in dogs and cats in comparison with standard methods]. Kleintierpraxis 37:183–199
Nairy KS, Rao KA (2003) Tests of coefficients of variation of normal population. Commun Stat-Simul C 32:641–661. doi:10.1081/SAC-120017854
Pang WK, Leung PK, Huang WK, Liu W (2005) On interval estimation of the coefficient of variation for the three-parameter Weibull, Lognormal and Gamma distribution: a simulation-based approach. Eur J Oper Res 164:367–377. doi:10.1016/j.ejor.2003.04.005
Petersen PH, Fraser CG, Jorgensen L, Brandslund I, Stahl M, Gowans EM, Libeer J-C, Ricos C (2002) Combination of analytical quality specifications based on biological within- and between-subject variation. Ann Clin Biochem 39:543–550. doi:10.1177/000456320203900601
Rishniw M, Pion PD, Maher T (2012) The quality of veterinary in-clinic and reference laboratory biochemistry testing. Vet Clin Pathol 41:92–109. doi:10.1111/j.1939-165x.2011.00386.x
Ross J, Fraser M (1977) Analytical clinical chemistry precision. State of the art for fourteen analytes. Am J Clin Pathol 68:130–141
Ross JW, Lawson NS (1995) Analytic goals, concentration relationships, and the state of the art for clinical laboratory precision. Arch Pathol Lab Med 119:495–513
Ross J, Fraser M, Moore T (1980) Analytic clinical laboratory precision—state of the art for thirty-one analysis. Am J Clin Pathol 74:521–530
Ruaux CG, Carney PC, Suchodolski JS, Steiner JM (2012) Estimates of biological variation in routinely measured biochemical analytes in clinically healthy dogs. Vet Clin Pathol 41:541–547. doi:10.1111/j.1939-165x.2012.00473.x
Schwendenwein I, Hooijberg E, Hanus B, Frommlet F, Pagitz M (2012) Variance components and critical differences in dogs and cats. In: 14th Conference of the European Society of Veterinary Clinical Pathology, Ljubljana, Slovenia. European Society of Veterinary Clinical Pathology
Sutton A, Dawson H, Hoff B, Grift E, Shoukri M (1999) Analyte comparisons between 2 clinical chemistry analyzers. Can Vet J 40:255–260
Trumel C, Diquélou A, Germain C, Palanché F, Braun JP (2005) Comparison of measurements of canine plasma creatinine, glucose, proteins, urea, alanine aminotransferase, and alkaline phosphatase obtained with Spotchem SP 4430 and Vitros 250 analyzers. Res Vet Sci 79:183–189. doi:10.1016/j.rvsc.2004.12.001
Tschudi PR (1995) Evaluation des Trockenchemie-Analysengerätes VetTest 8008 [Evaluation of the dry chemical analysis system VetTest 8008]. Schweiz Arch Tierheilkd 137:381–385
Vesper HW, Miller WG, Myers GL (2007) Reference materials and commutability. Clin Biochem Rev 28:139
Williams GZ, Young DS, Stein MR, Cotlove E (1970) Biological and analytic components of variation in long-term studies of serum constituents in normal subjects. I. Objectives, subject selection, laboratory procedures, and estimation of analytic deviation. Clin Chem 16:1016–1021
Acknowledgments
The authors would like to thank Dr. Kathleen Freeman for her expertise, guidance, and support as well as Gribbles Pathology (Heska Dri-chem and commercial laboratory), IDEXX Pathology, REM Systems (Vetscan) for providing analyzers and analytes and allowing independent scrutiny of their products.
Funding
This research received no grant from any funding agency in the public, commercial or not-for-profit sectors.
Human and Animal Rights
This article does not contain any studies with human or animal subjects.
Conflict of interest
The authors have no interest or association with any of the companies represented in this study and declare that there is no conflict of interest.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Baral, R.M., Morton, J.M., Dhand, N.K. et al. Repeatability of results from three in-house biochemistry analyzers and a commercial laboratory analyzer used in small animal practice. Comp Clin Pathol 24, 755–765 (2015). https://doi.org/10.1007/s00580-014-1977-8
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00580-014-1977-8