Viability of using digital signals from the keyboard to capture typing force exposures.
Kim JH; Johnson PW
Ergonomics 2012 Nov; 55(11):1395-1403
Although previous studies have shown that systematic temporal changes in keystroke durations may be used as surrogate measures of muscle fatigue, software-based keystroke duration may be adversely affected by different keyswitch force-displacement characteristics. Therefore, this study used a force platform to measure the keystroke durations and compared them to software-based measures in order to determine whether the software-based keystroke duration is a robust surrogate measure for the force-derived durations (independent of keyswitch designs). A total of 13 subjects typed for 15 minutes each on three keyboards with different force-displacement characteristics. The results showed that the software-based keystroke durations closely mirrored and approximated the true force-derived keystroke durations, regardless of the force-displacement characteristics. Furthermore, the subject-dependent correlations indicated that the software-based keystroke durations approximated the true force-derived keystroke durations. Therefore, the software-based keystroke durations could be used as a surrogate non-invasive, cost-effective measure to identify muscle fatigue during computer use for large-scale epidemiological studies. Practitioner Summary: Developing non-invasive, cost-effective computer exposure assessment tools can help researchers develop a better understanding on the underlying mechanisms of computer-related musculoskeletal disorders. This study demonstrates how software measured keystroke duration can be used as a non-invasive, cost-effective exposure assessment measure during computer use.
Keyboard-operators; Muscle-function; Muscles; Musculoskeletal-system; Musculoskeletal-system-disorders; Fatigue; Exposure-levels; Force; Humans; Men; Women; Measurement-equipment; Analytical-processes; Exposure-assessment;
Author Keywords: Computer use; musculoskeletal disorders; exposure assessment; keystroke duration; office ergonomics
Peter W. Johnson, Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
University of Washington