The DOI matches its Crossref record; 17 of the 17 references it cites were found in a registry or an index.
The validation of Fitbit Zip™ physical activity monitor as a measure of free-living physical activity
Open accessAbstract
BACKGROUND: The new generation of activity monitors allow users to upload their data to the internet and review progress. The aim of this study is to validate the Fitbit Zip as a measure of free-living physical activity. FINDINGS: Participants wore a Fitbit Zip, ActiGraph GT3X accelerometer and a Yamax CW700 pedometer for seven days. Participants were asked their opinion on the utility of the Fitbit Zip. Validity was assessed by comparing the output using Spearman's rank correlation coefficients, Wilcoxon signed rank tests and Bland-Altman plots. 59.5% (25/47) of the cohort were female. There was a high correlation in steps/day between the Fitbit Zip and the two reference devices (r = 0.91, p < 0.001). No statistically significant difference between the Fitbit and Yamax steps/day was observed (Median (IQR) 7477 (3597) vs 6774 (3851); p = 0.11). The Fitbit measured significantly more steps/day than the Actigraph (7477 (3597) vs 6774 (3851); p < 0.001). Bland-Altman plots revealed no systematic differences between the devices. CONCLUSIONS: Given the high level of correlation and no apparent systematic biases in the Bland Altman plots, the use of Fitbit Zip as a measure of physical activity. However the Fitbit Zip recorded a significantly higher number of steps per day than the Actigraph.
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“The Fitbit ZipTM has been found to be a valid measure of free-living physical activity in healthy adults [60].”
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Evenson, K. R., Goto, M. M., & Furberg, R. D. (2015) · International Journal of Behavioral Nutrition and Physical Activity · doi:10.1186/s12966-015-0314-1 · Cited by 1,232
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Accuracy of Fitbit Devices: Systematic Review and Narrative Syntheses of Quantitative Data
Feehan, L. M., Geldman, J., Sayre, E. C., Park, C., Ezzat, A. M., Yoo, J. Y., Hamilton, C. B., & Li, L. C. (2018) · JMIR mHealth and uHealth · doi:10.2196/10527 · Cited by 616
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Metadata
- Authors
- Tully, M. A., McBride, C., Heron, L., & Hunter, R. F.
- Affiliations
- Queen's University Belfast (GB)
- Corresponding author
- Tully, Mark A
- Venue
- BMC Research Notes
- Published
- 2014
- Volume
- 7
- Issue
- 1
- Pages
- 952
- ISSN
- 1756-0500 (ISSN-L)
- PMC
- PMC4307145
- OpenAlex
- W2102760209
- Cited by
- 172
- References
- 16
- Citations by year
- 2026: 2 · 2025: 6 · 2024: 9 · 2023: 6 · 2022: 8 · 2021: 16 · 2020: 25 · 2019: 19 · 2018: 19 · 2017: 26 · 2016: 24 · 2015: 11
- FWCI
- 13.56
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- cc-by
- Locations
- BMC Research Notes (publishedVersion, cc-by)
- Europe PMC (PubMed Central) (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- Research Portal (Queen's University Belfast) (acceptedVersion, other-oa)
- Funders
- Wellcome Trust
- United Kingdom Clinical Research Collaboration
- Alzheimer's Society
- Alzheimer's Research Trust
- Cancer Research UK
- National Institute for Health and Care Research
- British Heart Foundation
- Diabetes UK
- Stroke Association
- Public Health Agency
- Directorate for Biological Sciences
- Medical Research Council (MR/K023241/1)
- Engineering and Physical Sciences Research Council
- Economic and Social Research Council
- World Cancer Research Fund
- Health and Social Care Research and Development Division
- Topics
- Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Physical Activity and Health
- Physical Sciences › Computer Science › Computer Vision and Pattern Recognition › Context-Aware Activity Recognition Systems
- Health Sciences › Health Professions › General Health Professions › Mobile Health and mHealth Applications
- Keywords
- wearable activity trackers, accelerometer, pedometers, free-living physical activity, step count, device validation, ActiGraph GT3X+
- MeSH terms
- Adult, Female, Humans, Male, Physical Fitness, Telemetry, Reproducibility of Results, Cohort Studies, Walking, Monitoring, Ambulatory, Young Adult, Actigraphy, Independent Living, Accelerometry
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