Intolerance of uncertainty and smartphone addiction: mediating effects of reappraisal, suppression and rumination

The I-PACE (Interaction of Person–Affect–Cognition–Execution) model explains how behavioral addictions develop and persist through the interaction of individual predispositions with emotional and cognitive processes. In this context, examining how traits like intolerance of uncertainty (IU) may contribute to smartphone addiction (SPA) via emotion regulation processes is important. Although theoretically significant, empirical research on the mediating roles of specific emotion regulation strategies in this link remains limited. This study investigates whether cognitive reappraisal, suppression, and rumination mediate the relationship between IU and SPA. A total of 389 participants completed the Intolerance of Uncertainty Scale, the Emotion Regulation Questionnaire, the Ruminative Responses Scale – Short Form, and the Smartphone Addiction Scale. Correlational analyses showed positive associations between IU, suppression, rumination, and SPA. Mediation analyses, with age and gender included as covariates, revealed that among the examined emotion regulation strategies, only rumination significantly mediated the relationship between IU and SPA, whereas cognitive reappraisal and suppression did not exhibit significant indirect effects. These findings align with the assumptions of the I-PACE model by highlighting the differential impacts of emotion regulation strategies in behavioral addictions and underscoring rumination as a key psychological pathway linking IU to problematic smartphone use.