Differentiating Walking from other Activities of Daily Living in Older Adults Using Wrist-based Accelerometers

Abstract

There is a significant body of literature demonstrating that accelerometers placed at various locations on the body can provide the data necessary to recognize walking. Most of the literature, however, either does not consider accelerometers placed at the wrist, or suggests that the wrist is not the ideal location. The wrist, however, is probably the most socially-acceptable location for a monitoring device. This study evaluates the possibility of using wrist accelerometers to recognize walking in the elderly during everyday life to evaluate the amount of time spent walking and, moreover, potentially recognize changes in stability that might lead to falls. Thirty elderly individuals aged 65 years and older were asked to wear a wrist accelerometer for four hours each while simultaneously being video recorded as they went about their normal daily activities. Accelerometer data were then analyzed using both frequency- and time-domain analyses. Particular attention was given to methods capable of being calculated on the wrist device so that future work will not require streaming large amounts of data from the device to the central server. Frequency based analysis to characterize walking in the test set yielded results of 98% area under the receiver operating characteristic curve (AUC). Using a time-series algorithm limited to features calculable on the wrist device, moreover, achieved an AUC of 90%. A small, socially-acceptable, wrist-based device, therefore, can successfully be used to differentiate walking from other activities of daily living in older adults. These findings may enable improved gait monitoring and efforts in falls prevention.

Measuring Physical Activity with Hip Accelerometry among U.S. Older Adults: How Many Days Are Enough?

“…They may be helpful to characterize overall physical activity level, monitor intervention program adherence, and/or identify fall risk or frailty behaviors. [4, 5]…”

The Use of Inertial Measurement Units for the Study of Free Living Environment Activity Assessment: A Literature Review

“…It appears that the sensor placements in FLEs are globally homogeneous, including both lower and upper body parts. A clear trend does not emerge even if the wrist position seems to be predominant (twenty-four percent of the studies use this location [ 64 , 69 , 79 , 83 , 87 , 88 , 89 , 90 ]). Several inertial sensors are sensors implanted on a watch (ActiWatch, GENEActiv, etc.…”

“…In studies including only healthy participants (the majority of studies in this review) age is a recurring inclusion or exclusion criteria. Some studies focused on elderly populations, aged 65 and over [ 15 , 18 , 41 , 67 , 77 , 87 , 98 , 104 ]. Others focused on younger cohorts, with participants between adolescence and under 30 years of age [ 38 , 43 , 73 , 74 , 78 , 80 , 93 , 100 ].…”

A Review of Activity Trackers for Senior Citizens: Research Perspectives, Commercial Landscape and the Role of the Insurance Industry

“…Even though results were not sufficiently accurate, a significant difference in system performance was observed when the algorithms were trained with free-living data rather than laboratory data. On the other hand, [113] has proven the feasibility to discriminate between walking and other daily activities with a wrist-based accelerometer. A schematic comparison between the mentioned papers is shown in Table 2.…”