Brad Sokal1, Gitendra Uswatte2, Joydip Barman1, Michael Brewer1, Ezekiel Byrom1, Jessica Latten1, Jeethu Joseph1, Camila Serafim1, Touraj Ghaffari3, Nilanjan Sarkar4. 1. Department of Psychology, University of Alabama at Birmingham, Birmingham, AL. 2. Department of Psychology, University of Alabama at Birmingham, Birmingham, AL; Department of Physical Therapy, University of Alabama at Birmingham, Birmingham, AL. Electronic address: guswatte@uab.edu. 3. ActiveWave Inc, Boca Raton, FL. 4. Department of Mechanical and Computer Engineering, Vanderbilt University, Nashville, TN.
Abstract
OBJECTIVE: To test the convergent validity of an objective method, Sensor-Enabled Radio-frequency Identification System for Monitoring Arm Activity (SERSMAA), that distinguishes between functional and nonfunctional activity. DESIGN: Cross-sectional study. SETTING: Laboratory. PARTICIPANTS: Participants (N=25) were ≥0.2 years poststroke (median, 9) with a wide range of severity of upper-extremity hemiparesis. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: After stroke, laboratory tests of the motor capacity of the more-affected arm poorly predict spontaneous use of that arm in daily life. However, available subjective methods for measuring everyday arm use are vulnerable to self-report biases, whereas available objective methods only provide information on the amount of activity without regard to its relation with function. The SERSMAA consists of a proximity-sensor receiver on the more-affected arm and multiple units placed on objects. Functional activity is signaled when the more-affected arm is close to an object that is moved. Participants were videotaped during a laboratory simulation of an everyday activity, that is, setting a table with cups, bowls, and plates instrumented with transmitters. Observers independently coded the videos in 2-second blocks with a validated system for classifying more-affected arm activity. RESULTS: There was a strong correlation (r=.87, P<.001) between time that the more-affected arm was used for handling objects according to the SERSMAA and functional activity according to the observers. CONCLUSIONS: The convergent validity of SERSMAA for measuring more-affected arm functional activity after stroke was supported in a simulation of everyday activity.
OBJECTIVE: To test the convergent validity of an objective method, Sensor-Enabled Radio-frequency Identification System for Monitoring Arm Activity (SERSMAA), that distinguishes between functional and nonfunctional activity. DESIGN: Cross-sectional study. SETTING: Laboratory. PARTICIPANTS: Participants (N=25) were ≥0.2 years poststroke (median, 9) with a wide range of severity of upper-extremity hemiparesis. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: After stroke, laboratory tests of the motor capacity of the more-affected arm poorly predict spontaneous use of that arm in daily life. However, available subjective methods for measuring everyday arm use are vulnerable to self-report biases, whereas available objective methods only provide information on the amount of activity without regard to its relation with function. The SERSMAA consists of a proximity-sensor receiver on the more-affected arm and multiple units placed on objects. Functional activity is signaled when the more-affected arm is close to an object that is moved. Participants were videotaped during a laboratory simulation of an everyday activity, that is, setting a table with cups, bowls, and plates instrumented with transmitters. Observers independently coded the videos in 2-second blocks with a validated system for classifying more-affected arm activity. RESULTS: There was a strong correlation (r=.87, P<.001) between time that the more-affected arm was used for handling objects according to the SERSMAA and functional activity according to the observers. CONCLUSIONS: The convergent validity of SERSMAA for measuring more-affected arm functional activity after stroke was supported in a simulation of everyday activity.
Authors: Ryanne J M Lemmens; Yvonne J M Janssen-Potten; Annick A A Timmermans; Rob J E M Smeets; Henk A M Seelen Journal: PLoS One Date: 2015-03-03 Impact factor: 3.240