The effect of work-rest schedules and type of task on the discomfort and performance of VDT users

Ergonomics. 2003 Apr 15;46(5):455-65. doi: 10.1080/0014013021000047557.


Consideration of the literature survey indicates that video display terminal (VDT) operators tend to have a high incidence of musculoskeletal problems, visual fatigue, and job stress. Although a number of ergonomic improvements in workstation design and work environment can help to reduce these problems, a proper work-rest schedule deserves consideration since it is easily applicable and inexpensive. The objective of this study was to compare the work-rest schedules for VDT operators considering data entry and mental arithmetic tasks. An experiment was conducted with 10 male college students as participants. The methodology included a discomfort questionnaire and performance measures. The independent variables were the work-rest schedule (60-minute work/10-minute rest, 30-minute work/5-minute rest, and 15-minute work/micro breaks) and the type of task (data entry and a mental arithmetic task). The results were analysed using multiple analysis of variance followed by separate analyses. The 15/micro schedule resulted in significantly lower discomfort in the neck, lower back, and chest than the other schedules for data entry task. The 30/5 schedule followed by 15/micro schedule resulted in the lowest eyestrain and blurred vision. Discomfort in the elbow and arm was the lowest with the 15/micro schedule for the mental arithmetic task. The 15/micro schedule resulted in the highest speed, accuracy, and performance for both of the tasks, compared with the 60/10 and 30/5 schedules. The data entry task resulted in significantly increased speed, accuracy, and performance, and lower shoulder and chest discomfort than the mental arithmetic task.

MeSH terms

  • Adult
  • Computer Terminals*
  • Data Display
  • Ergonomics
  • Humans
  • Male
  • Multivariate Analysis
  • Musculoskeletal Diseases / physiopathology*
  • Musculoskeletal Diseases / prevention & control
  • Occupational Diseases / physiopathology*
  • Occupational Diseases / prevention & control
  • Posture / physiology
  • Students / psychology
  • Surveys and Questionnaires
  • Task Performance and Analysis*
  • User-Computer Interface
  • Work Schedule Tolerance*