Bash, K. (Berne). ‘Ein Vergleich dreierlei Messmethoden für die Extraversion/Introversion’ (A comparison of three methods for measuring extraversion/introversion).  Schweizerische Zeitschrift für Psychologie,  40, no. 2, pp.  91-107 (1981).

In this paper the author compares three tests that claim to measure extraversion and introversion (El). The preponderance of E or I in a person is used by some diagnosticians, for instance to differentiate reactive (E) from endogenous (I) depression. Bash examines three kinds of tests which were carried out on 31 male and female students aged 20 to 27 years at Berne University: 1. Colour tests (Lücher and Pfister-Heiss). 2. Rorschach test, 3. Questionnaires designed by Eysenck.

Bash questions whether these three tests measure the same phenomenon or rather different dimensions of experience. Moreover, Bash reminds us that Jung, who coined the concepts of extraversion and introversion, changed their meaning from indicating the direction of the libido to describing an attitude. The Lüscher test claims that more men than women are extravert whereas Eysenck sees no gender difference.

Bash uses well-established statistical methods. He finds that the three different tests show no agreement because, in his opinion, they measure different dimensions of experience. Hence the author doubts whether tests are of any use in diagnosing personality problems. However, Bash arrives at a significant by-product of the test results. He uses the chi-squared test which measures theoretical against observed results. This shows that his theory of bimodal distribution of experience values (published in Rorschachiana 1953) is borne out by observation.

This is a valuable paper, and the reviewer joins the author in the hope that it will stimulate further research.