Validating the sedentary sphere method in children : does wrist or accelerometer brand matter?

Hurter, L; Rowlands, AV; Fairclough, SJ; Gibbon, KC; Knowles, ZR; Porcellato, LA; Cooper-Ryan, AM; Boddy, LM

Abstract

This study aimed to validate the Sedentary Sphere posture classification method from wrist-worn accelerometers in children. Twenty-seven 9–10-year-old children wore ActiGraph GT9X (AG) and GENEActiv (GA) accelerometers on both wrists, and activPAL on the thigh while completing prescribed activities: five sedentary activities, standing with a phone, walking (criterion for all 7: observation) and 10-min free-living play (criterion: activPAL). In an independent sample, 21 children wore AG and GA accelerometers on the non-dominant wrist and activPAL for two days of free-living. Per cent accuracy, pairwise 95% equivalence tests (±10% equivalence zone) and intra-class correlation coefficients (ICC) analyses were completed. Accuracy was similar, for prescribed activities irrespective of brand (non-dominant wrist: 77–78%; dominant wrist: 79%). Posture estimates were equivalent between wrists within brand (±6%, ICC > 0.81, lower 95% CI ≥ 0.75), between brands worn on the same wrist (±5%, ICC ≥ 0.84, lower 95% CI ≥ 0.80) and between brands worn on opposing wrists (±6%, ICC ≥ 0.78, lower 95% CI ≥ 0.72). Agreement with activPAL during free-living was 77%, but sedentary time was underestimated by 7% (GA) and 10% (AG). The Sedentary Sphere can be used to classify posture from wrist-worn AG and GA accelerometers for group-level estimates in children, but future work is needed to improve the algorithm for better individual-level results.

• Journal Article Type: Article
• Acceptance Date: Apr 5, 2019
• Online Publication Date: Apr 23, 2019
• Publication Date: Apr 23, 2019
• Deposit Date: May 2, 2019
• Publicly Available Date: Apr 23, 2020
• Journal: Journal of Sports Sciences
• Print ISSN: 0264-0414
• Electronic ISSN: 1466-447X
• Publisher: Taylor and Francis
• Volume: 37
• Issue: 16
• Pages: 1910-1918
• DOI: https://doi.org/10.1080/02640414.2019.1605647
• Keywords: Physical Therapy, Sports Therapy and Rehabilitation, Orthopedics and Sports Medicine
• Publisher URL: https://doi.org/10.1080/02640414.2019.1605647
• Related Public URLs: https://www.tandfonline.com/toc/rjsp20/current