Abstract: The invention includes an in vitro bleeding time device having an opening through a sheet of material across an outlet. At least a portion the sheet of material contains a coating which includes collagen type I, fibrinogen, fibronectin, and von Willebrand factor. The invention includes a blood coagulation analysis system which has a device with an internal chamber for receiving a blood sample through an inlet. A sheet of material spans a flowpath through a single device outlet. A controller regulates pressure and or flow rate within the device. The invention includes a method for analyzing blood coagulation. Blood provided into a device chamber flows out through an opening through a sheet of material which spans the device outlet. A controller is utilized to control pressure and/or flow rate within the device by controlling the flow rate into the device during formation of a clot blockage of the opening.