Abstract: A system including two or more wearable devices includes at least one sensor in each device to detect signals related to the body of a wearer. User inputs, sensor outputs, or other information are used to determine an activity being performed or otherwise engaged in by the wearer and footsteps, heartbeats, discrete turns of the torso, or other events can be detected, from one or more of the sensor outputs, during a period of time that the user is engaged in the activity. A duration, amplitude, timing, mean value, or other characteristic of each such detected event can be determined, based on the sensor outputs, and used to generate a sample of clinically relevant information about the wearer. This information can then be used to determine the presence, stage, degree, progression, or other information about a disease state of the wearer or some other information about the wearer's body.