Cited by 28Physical Activity and HealthContext-Aware Activity Recognition SystemsSleep and related disorders

Validity of Two Awake Wear-Time Classification Algorithms for activPAL in Youth, Adults, and Older Adults

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Carlson, Jordan A., Tuz-Zahra, Fatima, Bellettiere, John, Ridgers, Nicola D., Steel, Chelsea, Bejarano, Carolina, LaCroix, Andrea Z., Rosenberg, Dori E. +3 more·2021·Journal for the Measurement of Physical Behaviour

Abstract

Background: The authors assessed agreement between participant diaries and two automated algorithms applied to activPAL (PAL Technologies Ltd, Glasgow, United Kingdom) data for classifying awake wear time in three age groups. Methods: Study 1 involved 20 youth and 23 adults who, by protocol, removed the activPAL occasionally to create nonwear periods. Study 2 involved 744 older adults who wore the activPAL continuously. Both studies involved multiple assessment days. In-bed, out-of-bed, and nonwear times were recorded in the participant diaries. The CREA (in PAL processing suite) and ProcessingPAL (secondary application) algorithms estimated out-of-bed wear time. Second- and day-level agreement between the algorithms and diary was investigated, as were associations of sedentary variables with self-rated health. Results: The overall accuracy for classifying out-of-bed wear time as compared with the diary was 89.7% (Study 1) to 95% (Study 2) for CREA and 89.4% (Study 1) to 93% (Study 2) for ProcessingPAL. Over 90% of the nonwear time occurring in nonwear periods >165 min was detected by both algorithms, while <11% occurring in periods ≤165 min was detected. For the daily variables, the mean absolute errors for each algorithm were generally within 0–15% of the diary mean. Most Spearman correlations were very large (≥.81). The mean absolute errors and correlations were less favorable for days on which any nonwear time had occurred. The associations between sedentary variables and self-rated health were similar across processing methods. Conclusion: The automated awake wear-time classification algorithms performed similarly to the diary information on days without short (≤2.5–2.75 hr) nonwear periods. Because both diary and algorithm data can have inaccuracies, best practices likely involve integrating diary and algorithm output.

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Authors
Carlson, J. A., Tuz-Zahra, F., Bellettiere, J., Ridgers, N. D., Steel, C., Bejarano, C., LaCroix, A. Z., Rosenberg, D. E., Greenwood-Hickman, M. A., Jankowska, M. M., & Natarajan, L.
Affiliations
  • University of Missouri–Kansas City (US)
  • 3University of California, San Diego
  • University of California San Diego (US)
  • Deakin University (AU)
  • 1Children’s Mercy
  • University of Kansas (US)
  • Kaiser Permanente Washington Health Research Institute (US)
Venue
Journal for the Measurement of Physical Behaviour
Published
2021-06-01
Volume
4
Issue
2
Pages
151-162
ISSN
  • 2575-6605 (ISSN-L)
  • 2575-6613
OpenAlex
W3157716729
Cited by
28
References
19
Citations by year
2026: 4 · 2025: 3 · 2024: 4 · 2023: 8 · 2022: 9
FWCI
3.29
Type
journal article
Language
en
Open access
Locations
  • Journal for the Measurement of Physical Behaviour (publishedVersion)
  • PubMed (publishedVersion)
  • PubMed Central (acceptedVersion)
  • UniSA Research Outputs Repository (University of South Australia) (submittedVersion)
  • Adelaide Research & Scholarship (AR&S) (University of Adelaide) (submittedVersion)
  • Figshare (submittedVersion, cc-by)
Funders
  • National Institute on Aging (U01AG006781)
  • National Heart, Lung, and Blood Institute (R01HL148463)
  • National Institute of Diabetes and Digestive and Kidney Diseases (R01DK114945)
Topics
  • Health Sciences › Medicine › Physiology › Physical Activity and Health
  • Physical Sciences › Computer Science › Computer Vision and Pattern Recognition › Context-Aware Activity Recognition Systems
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and related disorders
Keywords
activPAL, accelerometry, algorithm validation, sedentary behavior, self-rated health, older adults, youth, age differences

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