Impact of coincidence on granulocyte-platelet complex determination by flow cytometry is evaluated by a novel computer simulation model of coincidence

An excellent fit was found between computer simulated and measured data pairs. Bead mixture in the flow cytometer and simulation of that resulted in 37.3 ± 1.3 and 35.7 ± 0.6% double positivity, respectively. 30.2 ± 4.3% double positivity was measured for EDTA-anticoagulated blood samples while simulation of that resulted in 28.3 ± 0.6%. Double positivity attributed to platelet-granulocyte complexes in slightly diluted blood samples might originate in coincidence and not from true complexes.