The Vancouver Index of Acculturation (VIA): New evidence on dimensionality and measurement invariance across two cultural settings.

The Vancouver Index of Acculturation (VIA) is a self-report bidimensional instrument that has been employed in several cultural contexts to assess migrants’ orientations toward mainstream and heritage traditions. Although it has shown good reliability and validity in the past, recent theoretical developments and empirical studies have suggested the VIA might assess more than two dimensions. Moreover, measurement invariance of this instrument across demographic subgroups has never been assessed before. With the aim of evaluating these psychometric issues, exploratory factor analysis and Rasch modeling were conducted on data from two samples of immigrants to Canada (N = 224) and to Italy (N = 266). Results supported the hypothesized two-factor structure, with Rasch modeling showing that items within a subscale differed in terms of “difficulty” in being endorsed, but still belonged to a single factor. Differential item functioning analysis results showed measurement invariance across gender, age and education subgroups. Most results converged across the two samples.