A method and a device are provided for examining the properties of the global, in particular the primary, hemostasis functions in whole blood or platelet-rich plasma. A volumetric blood flow is preferably adjusted, depending on the measured pressure of the volumetric flow, so that the shear rate or the shear force, whose action in the reaction opening causes blood components, in particular thrombocytes, to deposit, follows a predetermined characteristic curve and in particular is held constant.