The Personal Expansion Questionnaire: Measuring one’s tendency to expand through novelty and augmentation

Previous research indicates that self-expansion, or acquiring a partner’s resources by “including the other in the self”, benefits satisfaction in romantic relationships (Aron, Mashek, & Aron, 2004). The present investigation seeks to broaden traditional conceptualizations of self-expansion by integrating it with principles of social penetration theory (Taylor, 1968) and considering expansion not only as a dyadic process, but also an individual personality trait. We have termed the newly conceptualized construct “personal expansion”. Three separate studies (N = 172 married adults, 606 undergraduate students, and 129 additional undergraduates, respectively) are presented to validate the Personal Expansion Questionnaire; a 10-item self-report scale developed to measure this newly defined construct. Results indicate a two factor structure underlying personal expansion. Both convergent and discriminant validity are established in comparison to one’s individual needs, affective traits, and the Big Five personality factors. Finally, test–retest reliability for the PEQ is demonstrated across five weeks. Consideration is given to the unique ways that personal expansion may be particularly relevant to long-term relationship success at both the individual and dyadic level.