Exploring Actical Accelerometers as an Objective Measure of Physical Activity in People With Multiple SclerosisBy Kayes, Nicola M.; Schluter, Philip J.; McPherson, Kathryn M.; Leete, Marta; Mawston, Grant; Taylor, Denise; Archives of Physical Medicine and Rehabilitation, Vol. 90, No. 4, pp. 594-601
Publication Date: April 2009
Study assessed the feasibility, acceptability, and test-retest reliability of the Actical accelerometer in people with multiple sclerosis (MS). The Actical accelerometer is described as an omnidirectional instrument which detects low-frequency gravitational forces common to human movement, then generates and digitizes a signal proportional to the magnitude and duration of the sensed acceleration, a value known as an activity count. Study participants were 31 individuals with MS who were purposely selected for diversity in age, sex, level of disability, and type of MS. Participants attended 2 testing sessions 7 days apart in which they completed 6 activities ranging in intensity while wearing an Actical accelerometer and Polar heart rate monitor. Perceived exertion was recorded after each activity. Accelerometers were found by the research team to be straightforward and easy to use, and acceptability of the devices was very high with participants. Test-retest reliability was poor for sedentary and free-living activities, with low to moderate intraclass correlation coefficients, but was better for more vigorous or rhythmic activities. Validity was not established, with 95 percent prediction intervals showing high variability for all activities. Based on these results, the authors conclude that Actical accelerometers should be used with caution in people with MS as a measure of physical activity, particularly when measuring comparatively sedentary or free-living activities.
Published by: W.B. Saunders Company, a division of Elsevier Health Sciences (Website:http://us.elsevierhealth.com)
American Academy of Physical Medicine and Rehabilitation (Web Site: http://www.aapmr.org/ )
American Congress of Rehabilitation Medicine (Web Site: http://www.acrm.org )
This publication is included in the library of the National Rehabilitation Information Center (NARIC), accession number J56600