COMMENTS ON "COMMENTS ON THE RELIABILITY OF A PERSONALITY QUESTIONNAIRE USED IN PHYSICAL EDUCATION AND SPORT RESEARCH

Summary.-The issue addressed concerns critical statements about the reliability of the Sixteen Personality Factor Questionnaire and related instruments made without benefit of appropriate statistical significance tests. The position argued is that such concltlsions are unwarranted. In a recent article Gruber (.1978) questioned the usefulness of the reliability data provided in the manuals for four personality questionnaires published by the Institute for Personality and Ability Testing (IPAT) of Champaign, Illinois. The four instruments, the Early School Personality Questionnaire, the Children's Personality Quesrionnaire, the High School Personality Questionnaire, and the Sixteen Personality Factor Questionnaire, each purport to measure between 14 and 16 dimensions of the normally functioning personality. They are, in fact, fairly popular research instruments, e.g., the 16 PF ranked second among all conlmercial personality inventories in number of published references during the 1969-1971 triennium (Buros, 1975, p. xxvii). Gruber (1978) compared reliability data collected in conjunction with three unpublished studies in physical education at the University of Kentucky with reliability data published in the manuals for the various IPAT personality questionnaires and reached the general conclusion that "much fluctuation exists between the reliabilities presented in the test manuals and those obtained in actual research studies" (p. 111). Gruber also concluded that reliabilities for the sexes are different, that reliabilities improve on retest, and that reliabilities are lower for emotionally disturbed children. These conclusions are not warranted by the evidence that Gruber presented in his article. The most flagrant violation of accepted scientific procedures was Gruber's failure to report appropriate tests of statistical significance. For example, Forms A and B of the 16 PF were administered to 22 college males and 30 college females. Equivalent form reliability coefficients (Form A with Form B) were calculated separately for the male and female samples. Gruber presented the coefficients in parallel columns in Table 1 (p. 116) and concluded that "Inspection of the data in Table 1 clearly reveals that there are distinct sex differences in trait reliabilities" (p. 115). From these data I calculated the appropriate statistical tests (Sokal & Rohlf, 1969, pp. 515-523) and found no significant differences between males and females. In other words, the observed differences between the male and female samples simply reflect random variability. I did not calculate statiscical tests for the remaining data which Gruber presented in Table 1 but, based on a careful examination of the coefficients, I doubt that any of the observed differences that Gruber "interpreted" are sta:istically significant. The responsibility for the statistical evaluation of the data is, of course, Gruber's. In two of the three unpublished studies that Gruber used to support his conclusions equivalent-form reliabilities were calculated and compared with similar data published in the IPAT manuals. However, for the types of research to which Gruber referred in his discussion, that is, studies in which the influence of exercise or sports activities on the personality characteristics of the participants is examined, whether using pre/post 'Reprints are available from the author at 346 N. West Avenue, Fayetteville, AR 72701.