A monitor for determining a patient's physiological parameter includes a calibration device that provides a calibration signal indicative of an accurate measurement of the patient's physiological parameter. The monitor also includes a processor, which receives a noninvasive signal from a noninvasive...http://www.google.com.au/patents/US6852083?utm_source=gb-gplus-sharePatent US6852083 - System and method of determining whether to recalibrate a blood pressure monitor
