Self Description Questionnaire Iii: The Construct Validity of Multidimensional Self‐concept Ratings by Late Adolescents

This research examines the validity of self‐concept interpretations of scores from a new instrument for use with university‐aged respondents. The Self Description Questionnaire III (SDQ III) was designed to measure 13 factors of self‐concept, and these dimensions were identified with conventional and confirmatory factor analyses. In two different studies, the reliabilities of the 13 factors were high (median alpha = 0.89) and correlations among the factors were low (median r = 0.09). Correlations among a wide variety of validity criteria and the multiple dimensions of self‐concept measured by the SDQ III formed a logical and theoretically consistent pattern of relationships. Academic achievement measures in language and mathematics were substantially correlated with self‐concepts in the same areas but not with other self‐concept factors. Ratings by significant others for all 13 SDQ HI scales were substantially correlated with the measures of corresponding self‐concepts, but were not substantially correlated with the measures of noncorresponding self‐concepts. These findings offer strong support for the construct validity of both self‐concept and interpretations based upon the SDQ III.