Does the Five Facet Mindfulness Questionnaire measure what we think it does? Construct validity evidence from an active controlled randomized clinical trial.

The current study attempted a rigorous test of the construct validity of a widely used self-report measure of dispositional mindfulness, the Five Facet Mindfulness Questionnaire (FFMQ), within the context of an active controlled randomized trial (n = 130). The trial included three arms: mindfulness-based stress reduction (MBSR), an active control condition that did not include instruction in mindfulness meditation (Health Enhancement Program [HEP]), and a waitlist control condition. Partial evidence for the convergent validity of the FFMQ was shown in correlations at baseline between FFMQ facets and measures of psychological symptoms and psychological well-being.