CLSI H44-A2

Methods for Reticulocyte Counting (Automated Blood Cell Counters, Flow Cytometry, and Supravital Dyes); Approved Guideline-Second Edit

NCCLS document H44-A2-Methods for Reticulocyte Counting (Automated Blood Cell Counters, Flow Cytometry, and Supravital Dyes); Approved Guideline-Second Edition provides guidance for the performance of reticulocyte counting by flow cytometry and automated hematology instruments. This guideline addresses methods for determining the precision and trueness of the flow cytometer and blood cell counters based upon principles of focused flow dynamics, along with recommendations for calibration and quality control. A description of the new methylene blue (NMB) method, a method against which the test instrument can be compared, is also included. Additional topics discussed include reference intervals and use of related reticulocyte parameters, i.e., the immature reticulocyte fraction (formerly termed "reticulocyte maturation index") and reticulocyte hemoglobin content (CHr).