%0 Journal Article %A Rowlands, Alex V. %A Mirkes, Evgeny M. %A Yates, Thomas E. %A Clemes, Stacy %A Davies, Melanie J. %A Khunti, Kamlesh %A Edwardson, Charlotte L. %D 2017 %T Accelerometer-assessed physical activity in epidemiology: Are monitors equivalent? %U https://repository.lboro.ac.uk/articles/journal_contribution/Accelerometer-assessed_physical_activity_in_epidemiology_Are_monitors_equivalent_/9626903 %2 https://repository.lboro.ac.uk/ndownloader/files/17275640 %K untagged %K Medical and Health Sciences not elsewhere classified %X PURPOSE: Accelerometers are increasingly being used to assess physical activity in large-scale surveys. Establishing whether key physical activity outcomes can be considered equivalent between three widely-used accelerometer brands would be a significant step towards capitalising on the increasing availability of accelerometry data for epidemiological research. METHODS: Twenty participants wore a GENEActiv, Axivity AX3 and ActiGraph GT9X on their non-dominant wrist and were observed for two-hours in a simulated living space. Participants undertook a series of seated and upright light/active behaviours at their own pace. All accelerometer data were processed identically using open-source software (GGIR) to generate physical activity outcomes (including average dynamic acceleration (ACC) and time within intensity cut-points). Data were analysed using pairwise 95% equivalence tests (±10% equivalence zone), intra-class correlation coefficients (ICC) and limits of agreement. RESULTS: The GENEActiv and Axivity could be considered equivalent for ACC (ICC=0.95, 95% confidence interval (CI) 0.87 to 0.98), but ACC measured by the ActiGraph was approximately 10% lower (ICC: GENEActiv/ActiGraph 0.86, 95% CI 0.56 to 0.95; Axivity/ActiGraph 0.82, 95% CI 0.50 to 0.94). For time spent within intensity cut-points, all three accelerometers could be considered equivalent to each other for over 85% of outcomes (ICC≥0.69, lower 95% CI≥0.36), with the GENEActiv and Axivity equivalent for 100% of outcomes (ICC≥0.95, lower 95% CI≥0.86). CONCLUSIONS: GENEActiv and Axivity data processed in GGIR are largely equivalent. If comparing GENEActiv or Axivity to the ActiGraph, time spent within intensity cut-points has good agreement. These findings can be used to inform selection of appropriate outcomes if comparing outputs from these accelerometer brands. %I Loughborough University