posted on 2023-10-03, 12:06authored byBenjamin D Maylor, Charlotte L Edwardson, Paddy C Dempsey, Matthew R Patterson, Tatiana Plekhanova, Tom Yates, Alex V Rowlands
Stepping-based targets such as the number of steps per day provide an intuitive and commonly used method of prescribing and self-monitoring physical activity goals. Physical activity surveillance is increasingly being obtained from wrist-worn accelerometers. However, the ability to derive stepping-based metrics from this wear location still lacks validation and open-source methods. This study aimed to assess the concurrent validity of two versions (1. original and 2. optimized) of the Verisense step-count algorithm at estimating step-counts from wrist-worn accelerometry, compared with steps from the thigh-worn activPAL as the comparator. Participants (n = 713), across three datasets, had >24 h continuous concurrent accelerometry wear on the non-dominant wrist and thigh. Compared with activPAL, total daily steps were overestimated by 913 ± 141 (mean bias ± 95% limits of agreement) and 742 ± 150 steps/day with Verisense algorithms 1 and 2, respectively, but moderate-to-vigorous physical activity (MVPA) steps were underestimated by 2207 ± 145 and 1204 ± 103 steps/day in Verisense algorithms 1 and 2, respectively. In summary, the optimized Verisense algorithm was more accurate in detecting total and MVPA steps. Findings highlight the importance of assessing algorithm performance beyond total step count, as not all steps are equal. The optimized Verisense open-source algorithm presents acceptable accuracy for derivation of stepping-based metrics from wrist-worn accelerometry.
Funding
This study was funded by/supported by the NIHR Applied Research Collaboration East Midlands (ARC EM). The SMART Work and Life study was funded by the National Institute for Health Research Public Health Research programme (project number 16/41/04). STAND UP was funded by the UK Medical Research Council Lifelong Health and Wellbeing Initiative in partnership with the Department of Health (grant number MR/K025090/1).
History
Citation
Maylor, B.D.; Edwardson, C.L.; Dempsey, P.C.; Patterson, M.R.; Plekhanova, T.; Yates, T.; Rowlands, A.V. Stepping towards More Intuitive Physical Activity Metrics with Wrist-Worn Accelerometry: Validity of an Open-Source Step-Count Algorithm. Sensors 2022, 22, 9984