What the evidence supports

A spurious CBC investigation begins with discordance, not a presumption that the specimen or method failed. Warming, plasma replacement, dilution, alternate anticoagulants, alternate counting channels, and manual estimates each have a defined target and local validation requirement.

ICGHR numerical and flag criteria can inform a locally adapted smear-review rule, but they are not universal release limits. CAP expects laboratories to define review criteria for flagged or discordant analyzer data, histograms, scattergrams, and blood films.

Document the observed evidence, intervention, verification, and endpoint. If a released result is erroneous, follow notification and corrected-report requirements; if the evidence does not resolve the discrepancy, suppress the result and pursue recollection, consultation, or escalation.