https://doi.org/10.1177/0734282918780565 Journal of Psychoeducational Assessment 1–13 © The Author(s) 2018 Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/0734282918780565 journals.sagepub.com/home/jpa Article The Reynolds Intellectual Assessment Scales: Measurement Invariance Across Four Language Groups Jasmin T. Gygi 1 , Thomas Ledermann 2 , Alexander Grob 1 , Myriam Rudaz 2 , and Priska Hagmann-von Arx 1 Abstract The Reynolds Intellectual Assessment Scales (RIAS) measures general intelligence and its two main components, verbal and nonverbal intelligence, each comprising of two subtests. The RIAS has been recently standardized in Denmark, Germany, Switzerland, and Spain. Using the standardization samples of the U.S. (n = 2,438), Danish (n = 983), German (n = 2,103), and Spanish (n = 1,933) versions of the RIAS, this study examined measurement invariance across these four language groups for a single-factor structure, an oblique two-factor structure with a verbal and nonverbal factor, and a bifactor structure with a general, a verbal, and a nonverbal factor. Single-group confirmatory factor analysis (CFA) supported the oblique two-factor and bifactor structure for each language group but not the single-factor structure. The bifactor analysis revealed that the general factor accounted for the largest proportion of common variance in each language group, while the amount of variance accounted for by the two specific factors was small and their reliabilities low. Multiple- group CFA supported scalar invariance in both, the oblique two-factor and bifactor structure. Keywords intelligence, Reynolds Intellectual Assessment Scales (RIAS), cross-cultural, measurement invariance Intelligence is one of the most frequently studied psychological constructs (e.g., Goldstein, Princiotta, & Naglieri, 2015). A more recently introduced intelligence test is the Reynolds Intellectual Assessment Scales (RIAS) developed in the United States by Reynolds and Kamphaus (2003) and normed for individuals between the ages of 3 and 90 years. Over the last decade, several studies have repeatedly demonstrated the convergent, discriminant, and predictive valid- ity of the RIAS version (Beaujean, Firmin, Michonski, Berry, & Johnson, 2010; Edwards & Paulin, 2007; Krach, Loe, Jones, & Farrally, 2009; Nelson & Canivez, 2012). Moreover, the RIAS has been evaluated to be independent of motor coordination, visual-motor speed, and 1 University of Basel, Switzerland 2 Florida State University, Tallahassee, FL, USA Corresponding Authors: Jasmin T. Gygi, Department of Psychology, University of Basel, Missionsstrasse 62, 4055 Basel, Switzerland. Email: jasmin.gygi@unibas.ch Thomas Ledermann, Department of Family and Child Sciences, Florida State University, 120 Convocation Way, Tallahassee, FL 32306. Email: tledermann@fsu.edu 780565JPA XX X 10.1177/0734282918780565Journal of Psychoeducational AssessmentGygi et al. research-article 2018