Effectiveness of the International Consensus Group criteria for manual peripheral smear review

ABSTRACT

Context The International Consensus Group for Hematology Review (ICGHR) are essentially review criteria designed to reduce the number of manual smear reviews following analysis in automated hematology analyzers (AHAs). Although AHAs are an indispensable part of the present-day clinical laboratory, manual smear reviews still play an integral role in identifying morphological abnormalities and to confirm the results of the analyzers. Aims: The aim of this study is to evaluate the efficacy of the ICGHR criteria and our laboratory criteria using the Sysmex XN-1000 for manual peripheral smear review (MSR). Study Design: A prospective cross-sectional comparative study between the two sets of criteria for MSR was performed. Material and Methods: A total of 860 whole blood samples sent over a period of 19 months for complete blood count testing to our laboratory were collected using systematic random sampling. Truth tables were prepared for each set of criteria. Tests of proportion were used to compare performance specifications between both sets of criteria. Results: Using ICGHR criteria, sensitivity was 81.58%, specificity was 84.61%, 83.38% positive predictive value, and 82.92% negative predictive value. The microscopic smear review rate was 47.56% and efficiency was 83.14%. Using our laboratory criteria, sensitivity was 98.80%, specificity was 41.40%, positive predictive value of 61.46%, and negative predictive value of 97.34%. The microscopic smear review rate was 78.14% and efficiency 69.30%. Conclusions: There was a significant reduction in the microscopic smear review rates using the ICGHR criteria compared to our laboratory criteria. The ICGHR criteria can thus be adapted to daily laboratory practice provided they are first optimized and locally validated before use.