Table 1

Basic characteristics and interpretation of commonly used assays to assess platelet function

Light transmission aggregometryPlasmaIncreased light transmission α increased platelet functionDoes not account for effect of blood cells on clotting
Impedance aggregometryWhole bloodIncreased impedance α increased platelet function
PFA-100Whole bloodDecreased closure time α increased platelet functionNot approved for detection of clopidogrel
VerifyNowWhole bloodAkin to light transmission aggregometry
TEG platelet mapWhole bloodDirectly reports the percentage of inhibition in maximal platelet functionVariable and high degree of inhibition noted due to illness and injury
  • TEG, thrombelastography-platelet mapping.