Reproducibility of Accelerometer-Assessed Physical Activity and Sedentary Time - PubMed (original) (raw)

Reproducibility of Accelerometer-Assessed Physical Activity and Sedentary Time

Sarah Kozey Keadle et al. Am J Prev Med. 2017 Apr.

Abstract

Introduction: Accelerometers are used increasingly in large epidemiologic studies, but, given logistic and cost constraints, most studies are restricted to a single, 7-day accelerometer monitoring period. It is unknown how well a 7-day accelerometer monitoring period estimates longer-term patterns of behavior, which is critical for interpreting, and potentially improving, disease risk estimates in etiologic studies.

Methods: A subset of participants from the Women's Health Study (N=209; mean age, 70.6 [SD=5.7] years) completed at least two 7-day accelerometer administrations (ActiGraph GT3X+) within a period of 2-3 years. Monitor output was translated into total counts, steps, and time spent in sedentary, light-intensity, and moderate to vigorous-intensity activity (MVPA) and bouted-MVPA (i.e., 10-minute bouts). For each metric, intraclass correlations (ICCs) and 95% CIs were calculated using linear-mixed models and adjusted for wear time, age, BMI, and season. The data were collected in 2011-2015 and analyzed in 2015-2016.

Results: The ICCs ranged from 0.67 (95% CI=0.60, 0.73) for bouted-MVPA to 0.82 (95% CI=0.77, 0.85) for total daily counts and were similar across age, BMI, and for less and more active women. For all metrics, classification accuracy within 1 quartile was >90%.

Conclusions: These data provide reassurance that a 7-day accelerometer-assessment protocol provides a reproducible (and practical) measure of physical activity and sedentary time. However, ICCs varied by metric; therefore, future prospective studies of chronic diseases might benefit from existing methods to adjust risk estimates for within-person variability in activity to get a better estimate of the true strength of association.

Copyright © 2016 American Journal of Preventive Medicine. All rights reserved.

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Appendix Figure 1

Flow-chart of participant eligibility and enrollment.

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References

    1. Physical Activity Guidelines Committee Report. U.S. DHHS; Washington, DC: 2008. www.health.gov/paguidelines/report.
    1. Haskell WL. Physical Activity by Self-Report: A Brief History and Future Issues. J Phys Act Health. 2012;9:S5–S10. - PubMed
    1. Lee IM, Shiroma EJ. Using accelerometers to measure physical activity in large-scale epidemiological studies: issues and challenges. Br J Sports Med. 2014;48(3):197–201. http://dx.doi.org/10.1136/bjsports-2013-093154. - DOI - PMC - PubMed
    1. Fishman EI, Steeves JA, Zipunnikov V, et al. Association between Objectively Measured Physical Activity and Mortality in NHANES. Med Sci Sports Exerc. 2016;48(7):1303–1311. http://dx.doi.org/10.1249/MSS.0000000000000885. - DOI - PMC - PubMed
    1. Loprinzi PD. Light-Intensity Physical Activity and All-Cause Mortality. Am J Health Promot. In press. Online January 5, 2016. http://dx.doi.org/10.4278/ajhp.150515-ARB-882. - DOI - PubMed

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