Assessing the measurement invariance of Free Will and Determinism Plus scale across four languages: a registered report

Free will is assumed to be the core of an individual's self-concept. Belief in free will has been studied extensively and was found to be correlated with many behavioural and psychological outcomes. Although developed and validated in the West, the Free will and Determinism Plus (FAD-Plus) scale has been translated, used, and interpreted as a measurement of free will beliefs in multiple cultures. However, the cross-cultural measurement invariance of FAD-Plus has not been examined. Given the cultural differences in understanding the concept of 'free will', items of FAD-Plus may have different interpretations in different cultures, which may compromise its cross-cultural measurement invariance. To provide empirical evidence for the lack of cross-cultural measurement invariance, we collected data in China and analyzed these data together with open datasets of FAD-Plus in three other languages: Japanese, French and English. We only found partial measurement invariance between the Chinese and English datasets, as well as the Japanese and English datasets. These results provided the first assessment of cross-cultural measure invariance of FAD-Plus. We discussed the potential implications of the current study for future studies in the field.