Personal assessment of intimacy in relationships: Validity and measurement invariance across gender

Introduction. - Intimacy is central in close relationships and a variety of definitions and instruments exist in scientific literature, making this concept complex to investigate. Furthermore, gender differences were identified in the definition and experience of intimacy. Objectives. - This study aims to confirm the three-factor structure of the personal assessment of intimacy in relationships (PAIR, Schaefer & Olson, 1981), commonly used in research and marital therapy, developed by Moore et al. (1998) and to examine the measurement equivalence of the scale across gender. Method. - A confirmatory factor analysis (CFA) was performed on the responses of 313 women and 251 men in committed relationships in a French population. Measurement equivalence of the scale across gender was then conducted with the best-fitting model. Results. - The results of CFA and post-hoc analyses revealed that the three-factor model revised with 18 items was the best fit to the data: (1) engagement (10 items), (2) communication (5 items), (3) shared friends (3 items). PAIR-18 displayed a lack of metric and scalar invariance across gender but estimated means of latent variables is not very different between the full invariant model and the unconstraint models. Conclusion. - Nevertheless, consideration of gender differences in the construct of intimacy is very important for theoretical research on intimacy in romantic relationships and for the interventions of marital therapists based on intimacy. (C) 2016 Published by Elsevier Masson SAS.