Is a 500-Cell Count Necessary for Bone Marrow Differentials?: A Proposed Analytical Method for Validating a Lower...

Area of Science:

• Hematology
• Laboratory Medicine
• Diagnostic Pathology

Background:

• Bone marrow aspirate differentials traditionally involve counting 500 cells.
• The evidence supporting the 500-cell cutoff is not well-established.
• Alternative cell counting strategies may be more efficient.

Purpose of the Study:

• To investigate if a reduced cell count of 300 is sufficient for bone marrow aspirate differentials.
• To compare diagnostic classifications between 300-cell and 500-cell counts.
• To assess the clinical and statistical validity of a 300-cell differential count.

Main Methods:

• Analysis of cell count data from 165 cases comparing 300-cell and 500-cell counts.
• Statistical testing for differences in cell percentages and diagnostic classifications.
• Method comparison analysis, bias plots, and contingency table analysis were performed.

Main Results:

• A 300-cell count did not result in diagnostically different outcomes compared to a 500-cell count.
• No statistically significant differences were observed for any cell type between the two methods.
• Bias plots indicated a narrow spread, and contingency tables showed no significant diagnostic discrepancies.

Conclusions:

• Performing bone marrow differential counts on 300 cells provides clinically and statistically similar results to 500 cells.
• Reducing the cell count to 300 has the potential for significant cost and labor reductions.
• The quality of care is not affected by decreasing the cell count from 500 to 300.