Considerations When Determining Similarity Between Traits and Skills: Raters and Item Types.

Recent research has examined similarities and differences between traits and skills. It may be the case that traits and skills can be measured interchangeably with one providing little to no incremental validity over the other. However, methodological limitations constrain our ability to draw firm conclusions. Work in this area thus far has only examined self-reports and single-stimulus Likert items. We carried out two studies to try to determine the extent to which methodology influences observed trait-skill similarity. In Study 1, we collected both self- and observer-reports of traits and skills, and in Study 2, we used both Likert and forced choice items. We examined whether trait-skill similarity in scores and validity evidence varied according to rater and item type. Our findings suggest that trait-skill similarity is unaffected by rater but is affected by item type; forced choice items lend themselves to greater trait-skill similarity.