After obtaining written informed consent and Protected Health Information (PHI) consent, CAM-ICU (Confusion Assessment Method for the ICU) will be measured routinely by unit nurses each shift. Results will be available in the medical record. We will then measure physical activity and physiological measures (e.g. ECG, heart rate, respiration rate, and body temperature) using an unobtrusive body worn sensor. This sensor will be attached to the 5th intercostal space using a specifically designed patch (BioPatchTM) to allow quantification of physical activity such as walking, standing, sitting, lying, as well as measurement of other physiological parameters. These measurements will only be available to the research team and will not be available to the nurses on the inpatient study unit. Medical history (from clinic chart) and demographic information will be obtained, such as age, gender, weight, and height as well as details (e.g. injuries, fall score and number of falls) which happened during hospital stay. The research tests consist of one core measurements and one ancillary measurements (as required) as listed below (Note - ancillary measurement may not be required for everyone).