The adult self expression scale: Validation by the multitrait-multimethod procedure

The present studies were designed to provide further validation of the Adult Self Expression Scale as a measure of assertive behavior for adults in general. Validation was approached by the Campbell and Fiske multitrait‐multimethod procedure and was concerned with the convergent relationship of assertion as measured by the Scale with measures of dominance and abasement as well as the discriminant capability of the instrument in terms of its relationship to various types of aggression, both verbal and physical. A variety of self‐report, peer‐rating, and unobtrusive measures were obtained from four distinct samples: participants in avocational interest classes at a technical institute, adults enrolled in an evening course in counseling theories at a state university, psychiatric inpatients, and convicted male felons. The results indicated that the Adult Self Expression Scale exhibits moderately strong convergent validity and moderate discriminant validity. The utility of the scale as a measure of assertive behavior for use with adults in general was supported.