Does Cognitive Fusion show up similarly across two behavioral health samples? Psychometric properties and invariance of the Greek–Cognitive Fusion Questionnaire (G-CFQ)

The Cognitive Fusion Questionnaire (CFQ) is a measure of cognitive fusion, a fundamental component of the psychological flexibility model, underlying Acceptance and Commitment Therapy (ACT). Numerous studies present cognitive fusion as a core pathological process contributing to psychological suffering, but none to date have examined phenomenological differences of this construct or assessed the CFQs' measuring performance across a clinical chronic pain sample vs. a sample of daily smoker university students. The purpose of this study was to examine the CFQ's psychometric properties in two Greek-speaking behavioral health samples (Sample 1: university student daily smokers, Sample 2: chronic pain patients) and assess its measurement model. Consistent with previous studies and the original English version, Exploratory and Confirmatory Factor Analysis, conducted separately per group, showed a unitary-factor solution for the Greek CFQ (G-CFQ). G-CFQ exhibited high internal reliability (Sample 1: Cronbach's α = 0.96, Sample 2: Cronbach's α = 0.95), good convergent validity with a theoretically related construct (Child and Adolescent Mindfulness Measure), good concurrent validity with the depression subscale of the Hospital Anxiety and Depression Scale and the Smoking Self-Efficacy Questionnaire and good discriminant validity with the Fagerström Test of Nicotine Dependence. Overall, the construct of cognitive fusion consists of items which are interpreted similarly across young adult smokers and chronic pain patients. The two groups differed in terms of the loadings on item 1, suggesting that they seem to understand this item differently. Also, these two populations were not significantly different in terms of their levels of cognitive fusion. Practical usability of the CFQ and future directions are discussed.