Validating an Activity Monitor for Acute Care Patients: The Patient/Resident Mobility Tracker (PREEMPT)

BACKGROUND AND PURPOSE: To validate an activity monitor, the Patient Resident Mobility Tracker (PREEMPT), appropriate for use with hospitalized individuals. METHODS AND MAIN OUTCOME MEASURES: Ten healthy older adults and 46 hospitalized patients wore the PREEMPT activity monitor while performing various physical activities. To determine accuracy and validity, the PREEMPT activity data were compared with video truth data. The five mobility metrics included stride length, number of steps, stepping time (total time spent walking), sedentary time and activity time. In addition to the objective data, participants answered 8 Likert scale usability questions about their experience wearing the PREEMPT device. RESULTS: The measurements taken by the PREEMPT device were statistically equivalent to criterion data for all five metrics with a geometric mean ratio ranging from 0.97 to 0.99. Statistical significance values (p) ranged from 0.043 to < 0.001 depending on the metric. The device received an average total score of 9.4 out of 10 on the Likert scale usability questions, indicating that the prototypical device was comfortable to wear and well received. DISCUSSION: These results demonstrate the initial validity and accuracy for the prototype PREEMPT device in healthy community-dwelling older adults as well as in hospitalized patients. The prototype PREEMPT device accurately measured physical activity in a relatively immobile population residing within a hospital setting. REPORTING METHOD: This paper adheres to STROBE guidelines. TRIAL REGISTRATION: This research was not a clinical trial and did not require registration.