McQuarrie and Munson (1986) challenged the strictly unidimensional structure of Zaichkowsky's (1985) PII, demonstrating via PCA that involvement contains both rational/cognitive facets (relevance, importance, utility) and emotional/affective facets (excitement, pleasure, appeal). The RPII re-specifies the PII as two 10-item factors. The Optimised PII (OPII) is a six-item short form selecting the three highest-loading items from each factor, suitable for time-constrained research. The Emotional subscale is most sensitive to hedonic product categories; the Rational subscale is more sensitive to high-risk utilitarian categories. The OPII is widely used as a covariate in advertising experiments.
McQuarrie, E.F., & Munson, J.M. (1986). The Zaichkowsky personal involvement inventory: Modification and extension. Advances in Consumer Research, 14, 36–40.
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