title: Evaluation of three methodologies for assessing work activity during computer use.
abstract: The overall goal of this study was to evaluate three separate methodologies for gathering work activity information among computer users. These methodologies included worker self-report, work sampling, and activity monitoring. A repeated measures design was employed whereby data were collected simultaneously on each subject (n = 51) across three consecutive workdays. Exposure information gathered included keying time, mouse usage, and time spent performing various work tasks (i.e., writing, proofreading, handling documents). Subjects were recruited to represent a wide range of keyboard activity and mouse usage. The study found that worker self-reports overestimated actual keyboard usage by a factor of approximately 1.5 for workers using the keyboard an average of 4 hours per day to a factor of 4 for workers using the keyboard an average of 30 min per day. On average, there was an approximate twofold difference between worker self-reported keying time and that obtained via activity monitoring and work sampling. This trend was similar with regard to time spent using the computer mouse. Worker self-reported mouse usage was approximately twofold higher than that obtained via activity monitoring or work sampling. Self-reported exposure information not only resulted in different estimates, but showed greater variance compared with the other methodologies. The results of this study suggest that the use of worker self-reported exposure information on keying time and mouse usage may not represent an accurate account of time spent performing these tasks. In the context of epidemiological studies work sampling and/or activity monitoring would be more suitable methodologies for obtaining such information.
authors.affiliation: Environmental Science and Engineering, Gannon University, 109 University Square, PMB 3663, Erie, PA 16541, USA. homan@gannon.edu
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Homan
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Armstrong
mesh_terms: D000328:Adult; D003201:Computers; D003625:Data Collection / Q000379:methods; D006804:Ergonomics; D005260:Female; D006801:Humans; D007587:Job Description; D008297:Male; D016273:Occupational Exposure; D015203:Reproducibility of Results; D013647:Task Performance and Analysis; D014342:Truth Disclosure; D014584:User-Computer Interface; D017132:Workplace