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Updated: Jun 24, 2026
A Method for Quantifying Upper Limb Performance in Daily Life Using Accelerometers
Published on: April 21, 2017
Exploring actical accelerometers as an objective measure of physical activity in people with multiple sclerosis
Nicola M Kayes1, Philip J Schluter, Kathryn M McPherson
1School of Rehabilitation and Occupation Studies, Health and Rehabilitation Research Centre, Auckland University of Technology, Auckland, New Zealand.
Objective:
To assess the feasibility, acceptability, and psychometric properties of Actical accelerometers in people with multiple sclerosis (MS).
Design:
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.
Setting:
University research center.
Participants:
People (N=31) with a definite diagnosis of MS were purposefully selected, aiming for diversity in level of reported disability, age, sex, and type of MS.
Interventions:
Not applicable.
Main Outcome Measures:
Actical accelerometer, Polar S810i and RS800sd heart rate monitors, Borg rating of perceived exertion, six-minute walk test (6MWT), 30-second chair stand test.
Results:
Accelerometers had good feasibility and acceptability in people with MS. Test-retest reliability was poor for sedentary and free-living activities, with low to moderate intraclass correlation coefficients (.00-.75), but was better for more vigorous or rhythmic activities (.85-.90). Bland-Altman 95% limits of agreement for average accelerometer counts were wide, ranging from +/-16 (newspaper reading) to +/-1330 (6MWT). Validity was not established with 95% prediction intervals showing high variability for all activities.
Conclusions:
The psychometric problems highlighted here suggest 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.
