The Personal Orientation Inventory: Internal Consistency, Stability, and Sex Differences

Abstract

Shostrom's Personal Orientation Inventory was assessed using test-retest, internal consistency (K-R 20), split-half reliability coefficients, and Sex × Trials analyses of variance. 172 university students were administered the inventory twice with 2 weeks inbetween. For the scales, Time Competence and Inner Direction, test-retest coefficients were .75 and .88, respectively. K-R 20 coefficients were .52 and .83, for first administration and .66 and .86 for second administration; and split-half coefficients were .50 and .84, and .73 and .87 for the two administrations, respectively. Ss' second scores tended to be higher than their first ones, and on some scales women scored higher than men and showed a greater increase than men. ω² estimates showed that all significant effects accounted for only small proportions of over-all sample variances. Hence, it is suggested that mean scores and changes in scores be interpreted with caution; that along with the probability of occurrence, the magnitude of the change should also be considered.