title: Expert assessment of physical ergonomics at video-display unit workstations: repeatability, validity and responsiveness to changes.
abstract: OBJECTIVE
  Inter-observer repeatability, validity and responsiveness to change were determined for an expert assessment method for video-display unit (VDU) workstation ergonomics. The aim was to determine to what extent the expert assessment of ergonomics is related to the technical measurements, tidiness and space, work chair ergonomics and responds to changes in these characteristics.
  
  
  METHODS
  Technical measurements and video-recordings before and 2 months after an ergonomic intervention were made for 109 VDU office workstations. Two experts in ergonomics analysed and rated the ergonomics of the workstations. A researcher analysed tidiness and available space. A physiotherapist classified the work chairs used according to their ergonomic properties.
  
  
  RESULTS
  The intra-class correlation coefficient between the workstation ergonomic ratings of the two experts was 0.74 at the baseline and 0.81 at the follow-up. Workstation tidiness and space, and work chair ergonomics, had a strong effect on the assessments of both experts. For both experts a change in the locations of the mouse, the screen and the keyboard and values of tidiness and space and work chair ergonomics during the intervention showed a significant association with the ratings.
  
  
  CONCLUSIONS
  The assessment method studied can be utilized by an expert in a repeatable manner both in cross-sectional and in longitudinal settings.
authors.affiliation: Department of Physiology, Finnish Institute of Occupational Health, 00250 Helsinki, Finland. ritva.ketola@ttl.fi
authors.forename: Ritva
authors.initials: R
authors.lastname: Ketola
authors.forename: Risto
authors.initials: R
authors.lastname: Toivonen
authors.forename: Ritva
authors.initials: R
authors.lastname: Luukkonen
authors.forename: Esa-Pekka
authors.initials: EP
authors.lastname: Takala
authors.forename: Eira
authors.initials: E
authors.lastname: Viikari-Juntura
mesh_terms: D000886:Anthropometry; D016287:Computer Peripherals; D016288:Computer Terminals; D006804:Ergonomics / Q000379:methods*; D005500:Follow-Up Studies; D006801:Humans; D007374:Interior Design and Furnishings / Q000145:classification / Q000592:standards*; D016272:Occupational Health; D011187:Posture; D011361:Professional Competence; D014741:Video Recording; D014796:Visual Perception; D017132:Workplace / Q000145:classification / Q000592:standards*