| Abstract: | Experiential avoidance (also referred to as acceptance or psychological flexibility) is a core construct of third-wave behavior therapies. It is the tendency to avoid uncomfortable thoughts or feelings, even when doing so has negative long-term consequences. In order for developments in experiential avoidance and third-wave behavior therapies to continue, it is imperative to examine the construct validity of the most widely used measures of this construct, the Acceptance and Action Questionnaire–II (AAQ-II) and the Multidimensional Experiential Avoidance Questionnaire (MEAQ). In Amazon’s Mechanical Turk (N = 1,052) and college (N = 364) samples, we evaluated the construct validity of these measures. The AAQ-II demonstrated suboptimal patterns of convergent and discriminant validity with measures of neuroticism/negative affect (Big Five Inventory, Big Five Aspects Scale, Positive and Negative Affect Schedule), the MEAQ, and mindfulness (Five Factor Mindfulness Questionnaire). In contrast, the MEAQ demonstrated optimal convergent and discriminant validity. Factor analyses at the scale, subscale, and item levels demonstrated that the AAQ-II loads with indicators of neuroticism/negative affect and not with other constructs at the core of third-wave behavior therapies. In contrast, the MEAQ loads on factors with mindfulness or forms its own factors. These findings suggest the AAQ-II functions as a measure of neuroticism/negative affect, whereas the MEAQ functions as an indicator of experiential avoidance. These findings have substantial implications for research on experiential avoidance and third-wave behavior therapies. Therefore, in order to improve the theory, research, and practice of third-wave behavior therapies, we recommend using the MEAQ to assess experiential avoidance. |
