Accuracy of the Actigraph wGT3x-BT for step counting during inpatient spinal cord rehabilitation

Abstract

Study design Cross-sectional. Objectives (1) Assess the accuracy of the Actigraph wGT3x-BT accelerometer to count steps taken by inpatients with incomplete spinal cord injury (iSCI) in physical therapy (PT) sessions and self-directed activities, and (2) compare the number of steps/min taken in PT sessions to that in self-directed activities during inpatient rehabilitation. Setting Inpatient spinal cord injury rehabilitation. Methods Seventeen individuals with subacute motor iSCI were observed for up to 45-min of both PT and self-directed activities, during which steps were simultaneously tracked by the Actigraph wGT3x-BT and a researcher using a hand tally counter. Accuracy was evaluated with an intraclass correlation coefficient (ICC) for the entire PT session and self-directed activities, as well as for periods of walking. Results There was excellent agreement between the Actigraph wGT3x-BT and manually counted steps for entire PT sessions (ICC = 0.86) and walking periods (PT walking, ICC = 0.99; self-directed walking, ICC = 0.99). There was poor agreement for entire self-directed sessions (ICC = 0.15). Visual analysis of Bland-Altman plots supported these findings. Participants took more steps/min in PT sessions compared to self-directed activities (p = 0.023). Conclusion The Actigraph wGT3x-BT accurately counts steps during PT sessions and walking periods in individuals with subacute motor iSCI. Clinically, this may enable physical therapists to track walking repetitions during inpatient rehabilitation more effortlessly.

Estimating physical activity and sedentary behaviour in a free-living environment: A comparative study between Fitbit Charge 2 and Actigraph GT3X

“…The AG is not a true criterion measure on PA outputs in a free living context and varying results have been found when testing the validity of AG against e.g. manual counted steps [34,[59][60][61]. For EE, doubly labeled water is considered the gold standard [62] and for measuring steps, it has been suggested that the StepWatch [63,64] is the most accurate while some have attempted the use of video-recording [65].…”

Criterion validity of ActiGraph monitoring devices for step counting and distance measurement in adults and older adults: a systematic review

“…Among these devices, ActiGraph is one of the most commonly used activity monitors for research in various populations [ 12 , 13 ]. ActiGraph is used to quantify the volume of walking (e.g., step count and distance) in people with incomplete spinal cord injury [ 14 ], hospitalized elderly [ 15 , 16 ], stroke survivors [ 17 – 19 ], children aged 10–17 years [ 20 , 21 ], people with multiple sclerosis [ 22 , 23 ], or in healthy people [ 24 – 27 ]. There are several models of ActiGraph that, vary according to type of sensors (e.g., accelerometer, gyroscope) and data processing (e.g., filter).…”

Quantifying Step Count and Oxygen Consumption with Portable Technology during the 2-Min Walk Test in People with Lower Limb Amputation

“…Since it is designed to be worn on the wrist, error of the vivofit3 on the ankle (VA) can be explained by its placement and, therefore, not recommended; however, error of the Link on the wrist and ankle (LW and LA, respectively) is more difficult to interpret since previous studies have found it to be accurate [67,68], while others found it to have a greater degree of error at various speeds [66,69]. Differences in findings may be explained by the placement of the device, surface on which participants walk (over ground or treadmill), sampling rate used (for example, 100 Hz as opposed to 50 Hz), population used (healthy, neurological disorder, elderly, etc.…”