With modern instrumentation, analytical precision is very high when the result is within the reportable range and no delta checks have failed. Providing that sample integrity and performance validity has been confirmed, repeating critical values rarely changes the result. However, turnaround time is significantly increased. This can delay clinical action, negatively impact patient care, and increase the likelihood of unnecessary investigations. For more information:
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Motie PB, Zare-Mirzaie A, Kadivar M. Does routine repeat testing of critical laboratory values improve their accuracy? Med J Islam Repub Iran 2015;29:176 PMID: 26034729.
Onyenekwu CP, Hudson CL, Zemlin AE, Erasmus RT. The impact of repeat-testing of common chemistry analytes at critical concentrations. Clin Chem Lab Med 2014;52(12):1739-45. PMID: 24940715.
Sun SP, Garcia J, Hayden JA. Repeating critical hematology and coagulation values wastes resources, lengthens turnaround time, and delays clinical action. Am J Clin Path 2018:149;247-52. PMID: 29425259.