Design and Validation of a Radio-Frequency Identification-Based Device for Routinely Assessing Gait Speed in a Geriatrics Clinic

OBJECTIVES: To evaluate the feasibility, acceptability, and validity of a radio-frequency identification (RFID)-based system to measure gait speed in a clinical setting as a first step to using unobtrusive gait speed assessment in routine clinical care. DESIGN: Feasibility study comparing gait speed assessed using an RFID-based system with gait speed assessed using handheld stopwatch, the criterion standard. SETTING: Outpatient geriatrics clinic at a Connecticut-based academic medical center. PARTICIPANTS: Clinic attendees who could walk independently with or without an assistive device (N=50) and healthcare providers (N=9). MEASUREMENTS: Gait speed was measured in twice using 2 methods each time before participants entered an examination room. Participants walked at their usual pace while gait speed was recorded simultaneously using the RFID-based system and a handheld stopwatch operated by a trained study investigator. After 2 trials, participants completed a brief survey regarding their experience. At the end of the study period, clinic healthcare providers completed a separate survey. RESULTS: Test-retest reliability of the RFID-based system was high (intraclass correlation coefficient = 0.953). The mean difference +/- standard deviation in gait speed between the RFID-based system and the stopwatch was -0.003 +/- 0.035 m/s (p=.53) and did not differ significantly according to age, sex, or use of an assistive walking aid. Acceptability of the device was high, and 8 of 9 providers indicated that measuring gait speed using the RFID-based system should be a part of routine clinical care. CONCLUSION: RFID technology may offer a practical means of overcoming barriers to routine measurement of gait speed in real-world outpatient clinical settings.