Cognitive Fusion Questionnaire: Exploring measurement invariance across three groups of Brazilian women and the role of cognitive fusion as a mediator in the relationship between rumination and depression

This study aimed to test the measurement invariance of the Brazilian version of the Cognitive Fusion Questionnaire (CFQ), to investigate its internal consistency, concurrent validity and to explore the role of cognitive fusion as a mediator of the effect of rumination on depression symptoms in women. The CFQ showed good model fit and its one-factor structure was confirmed. Strong measurement invariance was obtained (using three samples of women: general population, college students and a medical sample of women with overweight or obesity). The scale showed good internal consistency, CFQ's scores were positively associated with symptoms of depression, anxiety, stress, psychological inflexibility and rumination, and negatively associated with mindfulness and decentering. Also, cognitive fusion emerged as mediator of the effect of rumination on depression symptoms in a medical sample of women. In conclusion, this study provides data confirming the robust psychometric properties of the Brazilian version of the CFQ, allowing reliable comparatives studies between these three different populations of women.