More than a mirage: A large-scale assessment centre with more dimension variance than exercise variance

Assessment centres (ACs) are widely recognized to be among the best tools for assessing and developing management talent (Assessment Centres and Global Talent Management, 2011, Gower: London). Yet, the current consensus about the construct validity of ACs is that exercises rather than dimensions explain the majority of variance in ratings. Because much of the data on which these conclusions are based are now old, it is worthwhile to periodically re-examine this issue to see whether well-implemented designs produce better measurements of dimensions. We present results from 1,205 executive-level leaders from Fortune 500 firms across Europe and North America, who participated in developmental ACs that use modern design principles where assessors were formally examined to ensure they had a common frame or reference. Our results showed that while dimensions and exercises mutually determined ratings, more variation was owing to dimensions.