1. A method comprising: monitoring a plurality of signals, each of the signals generated by a respective one of a plurality of sensors as a function of posture of a patient; identifying a plurality of posture events based on the signals; associating each of the posture events with a therapy parameter set currently used by a medical device to deliver a therapy to the patient when the posture event is identified; and determining a value of a posture metric for each of a plurality of therapy parameter sets based posture events associated with the therapy parameter sets.