title: Internal consistency and test-retest reliability of an instrumented functional reaching task using wireless electromyographic sensors.
abstract: The purpose of this study was to establish the internal consistency and test-retest reliability of the electromyographic and accelerometric data sampled from the prime movers of the dominant arm during an antigravity, within-arm's length stand-reaching task without trunk restraint. Ten healthy young adults participated in two experimental sessions, approximately 7-10days apart. During each session, subjects performed 15 trials of both a flexion- and an abduction-reaching task. Surface EMG and acceleration using wireless sensors were sampled from the anterior and middle deltoid. Reliability was established using Cronbach's alpha, intraclass correlation coefficients (ICC 2, k) and standard error of measurements (SEM) for electromyographic reaction time, burst duration and normalized amplitude along with peak acceleration. Results indicated high degrees of inter-trial and test-retest reliability for flexion (Cronbach's α range=0.92-0.99; ICC range=0.82-0.92) as well as abduction (Cronbach's α range=0.94-0.99; ICC range=0.81-0.94) reaching. The SEM associated with response variables for flexion and abduction ranged from 1.55-3.26% and 3.33-3.95% of means, respectively. Findings from this study revealed that electromyographic and accelerometric data collected from prime movers of the arm during the relatively functional stand-reaching task were highly reproducible. Given its high reliability and portability, the proposed test could have applications in clinical and laboratory settings to quantify upper limb function.
authors.affiliation: Motor Behavior and Balance Rehabilitation Laboratory, Department of Physical Therapy, University of Illinois at Chicago, Chicago, USA.
authors.forename: Rini
authors.initials: R
authors.lastname: Varghese
authors.affiliation: Motor Behavior and Balance Rehabilitation Laboratory, Department of Physical Therapy, University of Illinois at Chicago, Chicago, USA.
authors.forename: Christina W Y
authors.initials: CW
authors.lastname: Hui-Chan
authors.affiliation: Motor Behavior and Balance Rehabilitation Laboratory, Department of Physical Therapy, University of Illinois at Chicago, Chicago, USA.
authors.forename: Edward
authors.initials: E
authors.lastname: Wang
authors.affiliation: Motor Behavior and Balance Rehabilitation Laboratory, Department of Physical Therapy, University of Illinois at Chicago, Chicago, USA. Electronic address: tbhatt6@uic.edu.
authors.forename: Tanvi
authors.initials: T
authors.lastname: Bhatt
mesh_terms: D000054:Acceleration; D000328:Adult; D001132:Arm / Q000502:physiology* / Q000503:physiopathology; D004576:Electromyography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D009068:Movement; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology*; D011930:Reaction Time; D015203:Reproducibility of Results; D055815:Young Adult
keywords: Abduction; Acceleration; Electromyography; Flexion; Reliability; Stand-arm reaching