BACKGROUND: The purpose of this study was to develop a data-driven approach for analyzing incomplete accelerometer data from field-base studies. METHODS: Multiple days of accelerometer data from the Stanford Girls health Enrichment Multi-site Studies (N = 294 African American girls) were summed across each minute of each day to produce a composite weekday and weekend day. Composite method estimates of physical activity were compared with those derived from methods typically described in the literature (comparison methods). RESULTS: The composite method retained 99.7% and 100% of participants in weekday and weekend-day analysis, respectively, versus 84.7% to 94.2% and 28.6% to 99.0% for the comparison methods. Average wearing times for the composite method for weekday and weekend day were 99.6% and 98.6%, respectively, 91.7% to 93.9% and 82.3% to 95.4% for the comparison methods. Composite-method physical activity estimates were similar to comparison-methods estimates. CONCLUSION: The composite method used more available accelerometer data than standard approaches, reducing the need to exclude periods within a day, entire days, and participants from analysis.
BACKGROUND: The purpose of this study was to develop a data-driven approach for analyzing incomplete accelerometer data from field-base studies. METHODS: Multiple days of accelerometer data from the Stanford Girls health Enrichment Multi-site Studies (N = 294 African American girls) were summed across each minute of each day to produce a composite weekday and weekend day. Composite method estimates of physical activity were compared with those derived from methods typically described in the literature (comparison methods). RESULTS: The composite method retained 99.7% and 100% of participants in weekday and weekend-day analysis, respectively, versus 84.7% to 94.2% and 28.6% to 99.0% for the comparison methods. Average wearing times for the composite method for weekday and weekend day were 99.6% and 98.6%, respectively, 91.7% to 93.9% and 82.3% to 95.4% for the comparison methods. Composite-method physical activity estimates were similar to comparison-methods estimates. CONCLUSION: The composite method used more available accelerometer data than standard approaches, reducing the need to exclude periods within a day, entire days, and participants from analysis.
Authors: Thomas N Robinson; Donna M Matheson; Helena C Kraemer; Darrell M Wilson; Eva Obarzanek; Nikko S Thompson; Sofiya Alhassan; Tirzah R Spencer; K Farish Haydel; Michelle Fujimoto; Ann Varady; Joel D Killen Journal: Arch Pediatr Adolesc Med Date: 2010-11
Authors: Paul Hendrick; Stephan Milosavljevic; Melanie L Bell; Leigh Hale; Deirdre A Hurley; Suzanne M McDonough; Markus Melloh; David G Baxter Journal: BMC Musculoskelet Disord Date: 2009-11-06 Impact factor: 2.362