(PS4-D84) The Impact of Intolerance of Uncertainty on Psychopathology: The Mediating Role of Experiential Avoidance

Introduction: Intolerance of uncertainty involves an inability to tolerate ambiguity in a variety of situations. Intolerance of uncertainty is positively correlated with depression, worry, and eating disorder severity. Emerging research on the mechanisms that link intolerance of uncertainty to maladaptive outcomes points to positive associations between intolerance of uncertainty and the overuse of experiential avoidance in stressful situations. This study evaluated experiential avoidance as a hypothesized mediator in the relationship between intolerance of uncertainty and general and eating-specific psychopathology in a non-clinical sample.

Method: Participants were recruited via Amazon’s MTurk to complete a battery of self-report measures, including the Eating Disorder Examination Questionnaire (EDE-Q), a measure of restraint and eating-, shape, and weight concern (Cronbach’s α in this sample = .93), Depression Anxiety Stress Scales (DASS-21), a measure of general psychopathology (α = .96), the Intolerance of Uncertainty Scale (IUS-27; α = .97), and the Brief Experiential Avoidance Questionnaire (BEAQ; α = .86). 270 participants started the survey; responses from 117 (60.9% female, mean age = 37.53 years, SD = 11.73) were deemed valid based on various attention checks and included in the analyses presented here. Preliminary analyses were conducted in RStudio; the hypothesized mediation model was tested in IBM SPPS AMOS v. 28. We assessed the indirect effect by examining the product of the A path and the B path while controlling for the direct effect of the C path. Significance was determined via bootstrapping with 500 resamples.

Results: Participants reported overall low levels of psychopathology as indicated by the Global EDE-Q score (M = 1.91, SD = 1.43), and DASS-21 depression, anxiety, and stress subscale scores (M = 5.05, SD =5.29; M = 3.50, SD = 4.69; M = 5.25, SD = 5.55, respectively). Intolerance of uncertainty was significantly and positively correlated with experiential avoidance; experiential avoidance, in turn, was significantly and positively correlated with DASS-21 subscales quantifying depression, anxiety, and stress and EDE-Q subscales measuring eating, shape, and weight concern (all p< .01). Analyses revealed a significant indirect effect of intolerance of uncertainty on EDE-Q scores [b= .02 (95% C.I.: .004, .03) p = .01]. The direct effect of intolerance of uncertainty on combined EDE-Q scores in presence of the mediator was not significant [b = .01 (95% C.I.: -.01, .04), p = 0.44], suggesting full mediation. Similarly, the indirect effect of intolerance of uncertainty on combined DASS-21 scores was significant [b= .06 (95% C.I.: .02, .12) p = .004], while the direct effect of intolerance of uncertainty on DASS-21 scores in the presence of the mediator was not significant [b = .02 (95% C.I.: -.03, .13), p = 0.43], suggesting full mediation.  

Conclusion: Results support the hypothesized role of experiential avoidance as a mediator in the relationship between intolerance of uncertainty and symptoms of diverse psychopathologies in a non-clinical sample. Future research should seek to replicate these findings in clinical populations and explore implications for treatment interventions.