Instrumenting gait with an accelerometer: a system and algorithm examination.
Gait is an important clinical assessment tool since changes in gait may reflect changes in general health. Measurement of gait is a complex process which has been restricted to the laboratory until relatively recently. The application of an inexpensive body worn sensor with appropriate gait algorithms (BWM) is an attractive alternative and offers the potential to assess gait in any setting. In this study we investigated the use of a low-cost BWM, compared to laboratory reference using a robust testing protocol in both younger and older adults. We observed that the BWM is a valid tool for estimating total step count and mean spatio-temporal gait characteristics however agreement for variability and asymmetry results was poor. We conducted a detailed investigation to explain the poor agreement between systems and determined it was due to inherent differences between the systems rather than inability of the sensor to measure the gait characteristics. The results highlight caution in the choice of reference system for validation studies. The BWM used in this study has the potential to gather longitudinal (real-world) spatio-temporal gait data that could be readily used in large lifestyle-based intervention studies, but further refinement of the algorithm(s) is required.
Institute of Neuroscience, Newcastle University, Campus for Ageing & Vitality, Newcastle upon Tyne, UK; Clinical Ageing Research Unit, Newcastle University, Campus for Ageing & Vitality, Newcastle upon Tyne, UK. Electronic address: alan.godfrey@ncl.ac.uk.
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Godfrey
Institute of Neuroscience, Newcastle University, Campus for Ageing & Vitality, Newcastle upon Tyne, UK; Clinical Ageing Research Unit, Newcastle University, Campus for Ageing & Vitality, Newcastle upon Tyne, UK.
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Del Din
Institute of Neuroscience, Newcastle University, Campus for Ageing & Vitality, Newcastle upon Tyne, UK; Clinical Ageing Research Unit, Newcastle University, Campus for Ageing & Vitality, Newcastle upon Tyne, UK; Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle upon Tyne, UK.
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Barry
Institute of Cellular Medicine, Newcastle University, Campus for Ageing & Vitality, Newcastle upon Tyne, UK; Human Nutrition Research Centre, Newcastle University, Campus for Ageing & Vitality, Newcastle upon Tyne, UK.
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Mathers
Institute of Neuroscience, Newcastle University, Campus for Ageing & Vitality, Newcastle upon Tyne, UK; Clinical Ageing Research Unit, Newcastle University, Campus for Ageing & Vitality, Newcastle upon Tyne, UK.
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Rochester
D061725:Accelerometry / Q000191:economics / Q000295:instrumentation / Q000379:methods*; D000328:Adult; D000368:Aged; D000465:Algorithms; D001696:Biomechanical Phenomena; D005684:Gait / Q000502:physiology; D006801:Humans; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000295:instrumentation / Q000379:methods; D016138:Walking / Q000502:physiology; D055815:Young Adult
Accelerometer; Algorithm; Gait; Healthy ageing; Validation