As an individual difference variable assessing the extent to which attitudes towards past, present and future influence behavior, time perspective is a potentially useful construct. However, its development and utility has been compromised by measurement issues. Recently, a short form of the Zimbardo Time Perspective Inventory (ZTPI), the SZTPI-15 has been suggested to yield valid and reliable scores. Using three independent samples from America, Australia, and the United Kingdom, the present study tested the psychometric properties of SZPTI-15 scores. Confirmatory factor analyses did not support the 5-factor structure and internal consistency estimates for four of the subscales were low. Fit indices obtained from exploratory structural equation modeling were better, suggesting that permitting items to load on multiple factors improved model fit. Correlations with variables shown to be related to ZTPI factors broadly supported the concurrent validity of the SZTPI-15. Results suggest that further psychometric examination of SZTPI-15 scores is required.
The Zimbardo Time Perspective Inventory (ZTPI; Zimbardo & Boyd, 1999) assesses five time-related constructs - Past Negative (PN), Past Positive (PP), Present Fatalistic (PF), Present Hedonistic (PF), and Future (F) - and is one of the most frequently used time measures in the extant literature. Versions of the ZTPI have been translated into a variety of languages, but the psychometric support for ZTPI scores remains contested. We examined the internal consistency, structural validity, and convergent validity of scores on a version of the ZTPI that consisted only of items that specifically referenced time constructs, the ZTPI-TP. Participants consisted of five samples of adolescents and adults from four countries: Australia (653 adults), Slovenia (425 adolescents and adults), the United Kingdom (913 adolescents; 455 adults), and the United States (815 adolescents). Structural validity analyses provided stronger support for ZTPI-TP scores than for ZTPI scores, and convergent validity evidence also provided support for ZTPI-TP scores. However, analyses revealed that the PF and PH factors were still problematic, especially with regard to factor coefficients and internal consistency estimates. We concluded that the ZTPI-TP can form the basis for a more robust version of the ZTPI.