Comparison of automated platelet counts and potential effect on transfusion decisions in cancer patients.

Objectives: To evaluate the accuracy of platelet counts from various hematology analyzers using a reference immunologic method.

Methods: We tested 403 samples with platelet counts less than 50 × 10(9)/L with the Advia (Siemens, Tarrytown, NY), Sysmex (Mundelein, IL), and Abbott (Santa Clara, CA) analyzers.

Results: All methods showed a positive bias, especially at less than 20 × 10(9)/L and less than 10 × 10(9)/L.