Counting Steps in Institutionalized Older Adults During Daily Life Activities: The Validation of Two Motion Sensors

The primary purpose of this study was to assess the validity of two motion sensors in measuring steps in institutionalized older adults during daily life activities. Sixty-eight nursing home residents (85.8 +/- 5.6 years) were equipped with a hip-worn and ankle-worn piezoelectric pedometer (New Lifestyles 2000) and with an arm-mounted multisensor (SenseWear Mini). An investigator with a hand counter tallied the actual steps. The results revealed that the multisensor and hip-and ankle-worn pedometer significantly underestimated step counts (89.6 +/- 17.2%, 72.9 +/- 25.8%, and 20.8 +/- 24.6%, respectively). Walking speed accounted for 41.6% of the variance in percent error of the ankle-worn pedometer. The threshold value for accurate step counting was set at 2.35 km/hr, providing percent error scores within +/- 5%. The ankle-worn piezoelectric pedometer can be useful for accurate quantification of walking steps in the old and old-old (>= 85 years) walking faster than 2.35 km/hr.