Validity of the Eysenck Extraversion Scale as Determined by Self-Ratings in Normals1

The E.P.I. was administered to 58 normal Ss who were students in three adult psychology classes. Immediately after responding to the E.P.I., Ss were asked to rate themselves on a seven-point introversion-extraversion scale. The Ss were divided into Introverts and Extraverts on the basis of their self-ratings. The Ss were also dichotomized into Introverts and Extraverts on the basis of E scores. Introvert and Extravert criterion groups were found to be significantly different from each other and from the total group. The results indicate that introverts as defined by self-ratings are somewhat more aware of their position on the Introversion-Extraversion continuum than are extraverts. Results support the validity of the E scale of the E.P.I. when using Introvert and Extravert criterion groups as defined above.