Development and Psychometric Properties of the Sport Imagery PETTLEP Inventory (SIPI)

Abstract

PETTLEP is an evidence-based applied model of imagery thought to allow athletes to practice vivid images. The present article aims to develop and evaluate psychometric properties of a PETTLEP-based instrument that measures athletes’ ability to image according to this model. Study 1 had 2 specialists and 283 amateur athletes. Inter-rater reliability was moderate (? = .54), internal consistency was high (? = .92) and scale’s number of items were cut by half using asymmetry, item-to-total correlation and differential item functioning as criteria. Volunteers of Study 2 were 322 elite athletes. Exploratory factor analysis revealed a single factor, whereas confirmatory factor analysis confirmed a hierarchical first-order structure with one higher factor. Convergent validity was assessed showing moderate correlation between the proposed measure and another imagery instrument (r = .54). The new instrument showed good psychometric properties and it reveals to be a reliable measure to assess imagery under PETTLEP approach.