Accuracy of StepWatch™ and ActiGraph Accelerometers for Measuring Steps Taken among Persons with Multiple Sclerosis

Abstract

IntroductionThere has been increased interest in the objective monitoring of free-living walking behavior using accelerometers in clinical research involving persons with multiple sclerosis (MS). The current investigation examined and compared the accuracy of the StepWatch activity monitor and ActiGraph model GT3X+ accelerometer for capturing steps taken during various speeds of prolonged, over-ground ambulation in persons with MS who had mild, moderate, and severe disability.MethodsSixty-three persons with MS underwent a neurological examination for generation of an EDSS score and undertook two trials of walking on the GAITRite electronic walkway. Participants were fitted with accelerometers, and undertook three modified six-minute walk (6MW) tests that were interspersed with 10–15 minutes of rest. The first 6MW was undertaken at a comfortable walking speed (CWS), and the two remaining 6MW tests were undertaken above (faster walking speed; FWS) or below (slower walking speed; SWS) the participant's CWS. The actual number of steps taken was counted through direct observation using hand-tally counters.ResultsThe StepWatch activity monitor (99.8%–99.9%) and ActiGraph model GT3X+ accelerometer (95.6%–97.4%) both demonstrated highly accurate measurement of steps taken under CWS and FWS conditions. The StepWatch had better accuracy (99.0%) than the ActiGraph (95.5%) in the overall sample under the SWS condition, and this was particularly apparent in those with severe disability (StepWatch: 95.7%; ActiGraph: 87.3%). The inaccuracy in measurement for the ActiGraph was associated with alterations of gait (e.g., slower gait velocity, shorter step length, wider base of support).ConclusionsThis research will help inform the choice of accelerometer to be adopted in clinical trials of MS wherein the monitoring of free-living walking behavior is of particular value.

Physical Activity Monitoring in Patients with Neurological Disorders: A Review of Novel Body-Worn Devices

“…Of the assessed studies, 10 included participants with multiple sclerosis [32][33][34][35][36][37][38][39][40][41], 7 included participants after stroke [32,33,[42][43][44][45][46], 4 included participants with PD [27,33,47,48], 3 included participants with a spinal cord injury [32,49,50], 2 included participants with cerebral palsy [51,52], 2 included participants with a traumatic brain injury [32,42], and participants with Rett syndrome [53] and muscular dystrophy [32] were included in 1 study each. The most frequently used monitors included the StepWatch activity monitor (a biaxial accelerometer) [39,41,42,44,53], the ActiGraph GT3X (a triaxial accelerometer) [35,39,40,50], the SWA (a multisensor device) [46,49,52], and the Digi-Walker pedometer [27,32,34,…”

A Randomized Crossover Trial of Dalfampridine Extended Release for Effect on Ambulatory Activity in People with Multiple Sclerosis

“…[15][16][17][18][19] We chose the PAI, an accelerometer-based outcome measure that reflected peak walking intensity (strides per minute), as the primary outcome. The secondary outcomes included steps per day and total percentage of the day spent in ambulation.…”

Impact of Activity Monitors on Quantification of Physical Activity - A Systematic Review & Meta-Analysis (Preprint)

“…Majority of studies used mixed gender population (n=14), 1 study targeted only males and 1 of females. Most of the studies included participants aged between 18-60 years (n=10) [16], [17], [21], [23], [26], [31], [32], [33], [25], [28] while five studies included participants older than 60 years of age [22], [23], [24], [27], [30] For both qualitative and quantitative analysis seven studies usedactivPAL [9], [17], [22], [24], [25], [29], [33] as an assessment measure of PA whereas eight studies used actigraph [9], [16], [17], [21], [22], [25], [27], [29]. Studies also used step watch [21], AMP 331 [30], mobile phone technology [32] CosMed Kb42 [29], IPAQ [23] and LAPAQ [24] respectively Figure 2 shows the risk of bias in terms of percentages in the studies…”