Validation of the Moral Foundations Questionnaire-2 (MFQ-2) in Germany: Psychometric properties and associations with political ideology, religiosity, and personality

Cross-cultural moral psychology requires robust, validated measures. The Moral Foundations Questionnaire-2 (MFQ-2) is a recent revision of the original MFQ that offers improved assessment of moral intuitions; however, a validated German version is unavailable, limiting moral psychology research in German-speaking populations. This Stage 1 Registered Report Protocol describes the methodology for developing and psychometrically validating a German version of the MFQ-2, with a target sample size of N ≈ 1,200. Its primary aim is to assess the instrument’s factor structure using Exploratory Structural Equation Modeling/Confirmatory Factor Analysis, reliability and measurement invariance. A secondary aim is to provide initial construct validity by examining associations with psycho-social correlates, including political ideology, religiosity, personality, and ethics positions. We will test whether theoretically predicted patterns emerge in the German context. By providing a methodologically validated tool, this research will enable investigation of moral belief structures in German-speaking countries and facilitate cross-cultural comparisons in moral psychological science. This is the Stage 1 Registered Report Protocol for: Musa NS, Müller SM, Hopp FR (2026) Validation of the moral foundations questionnaire-2 (MFQ-2) in Germany: Psychometric properties and associations with political ideology, religiosity, and personality. PLoS One 21(3): e0345599. https://doi.org/10.1371/journal.pone.0345599 unknown other