On ratings of comfort and exertion by visual display unit users and ratings of workplace layout and working posture by expert ergonomists.

Data sets comparing ratings of comfort and perceived exertion by visual display unit (VDU) users with ratings of workplace layout and working posture by expert ergonomists were published by Lindegård et al. [2005. Concordance between VDU-users' ratings of comfort and perceived exertion with experts' observations of workplace layout and working postures. Appl. Ergon. 36, 319-325]. The present paper corrects the conclusions that were drawn. Users' and experts' ratings were very largely independent of each other. It is also noted that polychoric correlation is often an appropriate statistic for summarising the association in ordered tables of frequencies.