Personality test item validity: insights from “self” and “other” research and theory

This research examined the effects of item-evoked cognitive response strategy and test-taking instructional set on the psychometric properties of personality scales. University undergraduate roommate pairs (N = 192) responded to subscales from typical personality inventories under either standard, trait-focused, or behaviour-focused instructions. Results indicated that behavioural-based instructions combined with behavioural-focused items significantly decreased indices of subscale reliability, validity, and a composite measure of goodness. Findings are interpreted with respect to social cognition theories concerning perception of the “self” and the “other”. Implications for personality test item writing and item pool selection are discussed.