The Cochran-Weiss-Shanteau performance index as an indicator of upper limb risk assessment expertise.

Ergonomists and many other professionals apply ergonomics principles to musculoskeletal health problems. This study examines whether there are differences when it comes to judgement expertise concerning upper limb disorders (ULDs) between ergonomists and those with less ergonomics training. The Cochran-Weiss-Shanteau (CWS) performance index combines judgement consistency with discrimination into one CWS index. Fifty-eight professionals working in the musculoskeletal health area, from four different professions, judged the likelihood of staff complaining of ULDs in a number of written work scenarios containing ULD risk factors. A student group (n = 148) taking an introductory ergonomics module was used as a reference. The ergonomists scored higher on the CWS index than all of the other groups, performing significantly better than all but the occupational health advisors. Performance improved with increased training level but not with experience. This study suggests that ergonomists are quantifiably different from other ergonomics advisors in their judgement performance in this context. Given the global cost of musculoskeletal disorders, assessing the expertise of those giving ergonomics advice for the management of musculoskeletal health is of great significance. This study presents a method for assessing judgement performance in ULD risk assessment, an important part of musculoskeletal health management.