Three versions of the Interpersonal Adjective Scales and their fit to the circumplex model

The Interpersonal Adjective Scales (IAS) is a well-supported instrument that is designed to map interpersonal traits onto the interpersonal circumplex. However, three versions of the IAS exist and these vary with respect to the degree to which they included item definitions (i.e., glossary added at the end, definitions attached to each item, and no definitions). The focus of this study was on comparing the structural similarity of each version. Each of the versions was given to different samples (N = 920) of college students. Results of multidimensional scaling (MDS) and randomized tests of order relations demonstrated that all versions were well and equally described by the circular model. There were no structural differences in the different IAS versions and thus each can be used with this population.