What this workup supports and what it does not

No universal numeric cutoff applies across light-transmission aggregometry, impedance aggregometry, lumiaggregometry, or flow cytometry. A normal PFA result does not exclude every mild platelet disorder, and one trace, cartridge pair, or agonist panel does not diagnose an inherited platelet-function defect. Those patterns require the method limits, specimen, medication history, and qualified review to be considered together.

Every method-specific detail above, including analyzer models, reagent lots, exact agonist concentrations, reportable ranges, and the reference intervals a laboratory actually reports, depends on the current local validated procedure and the manufacturer's current instructions for use. Before releasing results from an unmodified FDA-cleared platform, the laboratory verifies accuracy, precision, reportable range, and the appropriateness of the manufacturer's reference intervals for its own population; a modified or non-cleared system requires the laboratory to establish its own full performance specifications first.

A platelet-function result tells you what the method measured, and a pattern across a panel is what you weigh against the clinical question, the specimen, and the medication history before anyone writes a diagnosis on the chart.