Determining platelet aggregation values

An embodiment system includes a chamber containing a mixture comprising a whole blood sample from a patient, a light source to illuminate the mixture in the chamber, a detector to detect light transmitted through the mixture in the chamber from the light source, and one or more processing devices, and a processor to determine a platelet aggregation value of the whole blood sample based on the light detected by the detector, the value being substantially independent of the hematocrit of the whole blood sample. 实施例系统包括容纳混合物的腔室，该混合物包括来自患者的全血样品，用于照亮腔室中的混合物的光源，检测来自光源的、通过腔室中的混合物传输的光的检测器，以及一个或多个处理装置，以基于检测器检测到的光确定全血样品的血小板聚集值，该值基本上独立于全血样品的红细胞压积。