A method of determining patient-specific calibration values (pwv 0, a) for use in a continuous blood pressure measurement based on pulse wave velocity, the method comprising: positioning (i) a sensor device on a patient, the sensor device configured to measure sensor data indicative of pulse arrival time at a first point on an extremity of the patient, the PAT defined as a time difference between ventricular depolarization occurring in a cardiac cycle, and arrival of a pressure wave at the first point resulting from blood flow caused by the ventricular depolarization through a vascular path of length Lt, wherein the sensor device is operably connected to a processing component, and (ii) an inflatable cuff device on the patient's extremity at a second point on the extremity of the patient at a position on the vascular path between the heart and the first point, the inflatable cuff device comprising an inflatable cuff which is configured to cover a portion of the vascular path of length Lc and an inflation pump, the inflatable cuff device configured to measure a waveform indicative of cuff pressure on the patient's extremity during inflation, wherein the inflatable cuff device is operably connected to the processing component; receiving at the processing component the sensor data and the waveform indicative of cuff pressure, and causing the processing component to calculate therefrom a series of pulse arrival times ("PATs") as a function of cuff pressure during inflation of the inflatable cuff to above the patient's systolic blood pressure, wherein the inflation causes a compliance change in the vascular path of length Lc, thereby causing the PAT measured by the sensor device to lengthen as cuff pressure is increased; and determining using the processing component one or more coefficients (pwv 0, a) which relate PWV to mean arterial pressure by modeling the series of PATs measured as a function of cuff pressure as a nonlinear relationship; the method being characterized in that the nonlinear relationship is expressed as PAT t = L t − L c aMAP cal + pwv 0 + L c a MAP cal − P cuff t + pwv 0 wherein pwv 0 is the PWV through the portion of the vascular path covered by the inflatable cuff, and a is a constant. positioning (i) a sensor device on a patient, the sensor device configured to measure sensor data indicative of pulse arrival time at a first point on an extremity of the patient, the PAT defined as a time difference between ventricular depolarization occurring in a cardiac cycle, and arrival of a pressure wave at the first point resulting from blood flow caused by the ventricular depolarization through a vascular path of length Lt, wherein the sensor device is operably connected to a processing component, and (ii) an inflatable cuff device on the patient's extremity at a second point on the extremity of the patient at a position on the vascular path between the heart and the first point, the inflatable cuff device comprising an inflatable cuff which is configured to cover a portion of the vascular path of length Lc and an inflation pump, the inflatable cuff device configured to measure a waveform indicative of cuff pressure on the patient's extremity during inflation, wherein the inflatable cuff device is operably connected to the processing component; (i) a sensor device on a patient, the sensor device configured to measure sensor data indicative of pulse arrival time at a first point on an extremity of the patient, the PAT defined as a time difference between ventricular depolarization occurring in a cardiac cycle, and arrival of a pressure wave at the first point resulting from blood flow caused by the ventricular depolarization through a vascular path of length Lt, wherein the sensor device is operably connected to a processing component, and (ii) an inflatable cuff device on the patient's extremity at a second point on the extremity of the patient at a position on the vascular path between the heart and the first point, the inflatable cuff device comprising an inflatable cuff which is configured to cover a portion of the vascular path of length Lc and an inflation pump, the inflatable cuff device configured to measure a waveform indicative of cuff pressure on the patient's extremity during inflation, wherein the inflatable cuff device is operably connected to the processing component; receiving at the processing component the sensor data and the waveform indicative of cuff pressure, and causing the processing component to calculate therefrom a series of pulse arrival times ("PATs") as a function of cuff pressure during inflation of the inflatable cuff to above the patient's systolic blood pressure, wherein the inflation causes a compliance change in the vascular path of length Lc, thereby causing the PAT measured by the sensor device to lengthen as cuff pressure is increased; and determining using the processing component one or more coefficients (pwv 0, a) which relate PWV to mean arterial pressure by modeling the series of PATs measured as a function of cuff pressure as a nonlinear relationship; the method being characterized in that the nonlinear relationship is expressed as PAT t = L t − L c aMAP cal + pwv 0 + L c a MAP cal − P cuff t + pwv 0 wherein pwv 0 is the PWV through the portion of the vascular path covered by the inflatable cuff, and a is a constant.