Linking Expectancies and Interpretations: A Transdiagnostic Mediation Model of Intolerance of Uncertainty

Expectancy and interpretation biases are widely considered transdiagnostic markers of psychopathology, yet the nature of their relationship remains understudied. If these processes are causally related, modifying one may influence the other and reduce associated symptoms. Intolerance of uncertainty (IU) is a transdiagnostic trait linked to biased interpretations and their modification. The present study tested a mediation model in which interpretations were hypothesized to mediate the relationship between expectancies and IU. According to this account, expectancy-related ratings were expected to predict interpretation-related ratings, which in turn were expected to predict trait IU. In an online study, N = 263 unselected participants completed a novel task in which each trial paired an expectancy sentence and rating with a subsequent interpretation sentence and rating, jointly assessing both processes. Sentence valence (neutral/emotional) and expectancy-interpretation outcome pairings (e.g., positive-positive, positive-negative) varied randomly across trials. Results showed that more negative expectancy and interpretation ratings were associated with higher levels of trait IU, anxiety, and depression, whereas more positive ratings were associated with lower levels of each. In a cross-sectional mediation model, expectancies showed significant direct paths to both interpretations and IU, but interpretations did not mediate the expectancy-IU relationship. These findings point to a central transdiagnostic role for expectancies relative to interpretations. Interventions may therefore benefit from prioritizing expectancy biases; nonetheless, the observation that expectancy and interpretation biases were associated with symptom measures in opposing and complementary directions indicates that joint assessment of both cognitive processes remains more informative than assessing either alone.