According to one embodiment of the present invention, the system for clinical assessment of movement disorders (iTUG) is comprised of a) a protocol to assess gait, balance, and mobility; b) a plurality of wearable sensors including accelerometers, gyroscopes, magnetometers, optical sensors, and goniometers to record kinematics data obtained from a patient during said protocol; c) means for wirelessly transmitting said kinematics data to a storage and data processing server; and d) a plurality of statistical and biomedical signal processing methods to analyze said kinematic data and derive a plurality of metrics (outcomes) to objectively quantify movement disorders. A specially important outcome for the assessment of movement disorders is described, namely, the quantification of the onset and offset parameters during turning. A method for quantification of said onset and offset turning parameters involves 1) collecting data to measure the angle of the trunk during turning, 2) modeling said angle using a mathematical model, and 3) using numerical optimization and estimation methods for fitting the model in the data to determine said onset and offset turning parameters.
System for clinical assessment of movement disorders