Letters2 January 2007
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    TO THE EDITOR:

    The recent article about estimated glomerular filtration rate (GFR) by Levey and colleagues (1) is remarkable. The authors suggest that the new equation may still have some bias and especially may have less precision in patients with GFRs greater than 60 mL/min per 1.73 m2. This is even more important if the GFR is greater than 90 mL/min per 1.73 m2. In the paper's Methods section, Levey and colleagues do not give the analytic coefficient of variation (CV) of their assays (Beckman Synchron CX3 [Global Medical Instrumentation, Inc., Ramsey, Minnesota] and Roche/Hitachi P module Creatinase Plus enzymatic ...

    References

    • 1. Levey ASCoresh JGreene TStevens LAZhang YLHendriksen Set alUsing standardized serum creatinine values in the Modification of Diet in Renal Disease Study equation for estimating glomerular filtration rate. Ann Intern Med2006;145:247-54. [PMID: 16908915] LinkGoogle Scholar
    • 2. Costongs GMJanson PCBas BMHermans Jvan Wersch JWBrombacher PJShort-term and long-term intra-individual variations and critical differences of clinical chemical laboratory parameters. J Clin Chem Clin Biochem1985;23:7-16. [PMID: 3981091] MedlineGoogle Scholar
    • 3. Ricós CAlvarez VCava FGarcía-Lario JVHernández AJiménez CVet alCurrent databases on biological variation: pros, cons and progress. Scand J Clin Lab Invest1999;59:491-500. [PMID: 10667686] CrossrefMedlineGoogle Scholar
    • 4. Froissart MRossert JJacquot CPaillard MHouillier PPredictive performance of the modification of diet in renal disease and Cockcroft-Gault equations for estimating renal function. J Am Soc Nephrol2005;16:763-73. [PMID: 15659562] CrossrefMedlineGoogle Scholar
    • 5. Delanaye PCavalier EKrzesinski JMChapelle JPWhy the MDRD equation should not be used in patients with normal renal function (and normal creatinine values)? [Letter]. Clin Nephrol2006;66:147-8. [PMID: 16939074] CrossrefMedlineGoogle Scholar