Validating a brief measure of the Zimbardo Time Perspective Inventory

Zimbardo and Boyd (1999) developed the 56-item Zimbardo Time Perspective Inventory (ZTPI). It has become the leading measure used in the study of subjective time. In this article, we report an abbreviated ZTPI that only includes 15 total items (SZTPI-15). We tested the psychometric characteristics of the SZTPI-15 by focusing on: (a) convergent and discriminant validity, (b) external validity, (c) test–retest reliability and (d) self-peer ratings. On the basis of these tests, the results demonstrated that the short version was less reliable than the standard ZTPI but showed impressive psychometric convergence with the standard ZTPI.