Information diagnosticity and booking intention in online travel agencies: The sequential mediating roles of epistemic trust and booking attitude

Online travel agencies (OTAs) increasingly shape how travelers search for information, evaluate alternatives, and make booking decisions. Despite extensive research on information quality and trust, limited attention has been given to the sequential cognitive mechanisms linking information evaluation to booking intention. This study examined the sequential mediating roles of epistemic trust and booking attitude in the relationship between information diagnosticity and booking intention in OTAs. Grounded in accessibility–diagnosticity theory and the Theory of Planned Behavior, information diagnosticity was conceptualized through two distinct dimensions: information quality and task support. Data from 244 individuals with prior OTA experience were analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM) with bootstrapping. The model explained 31.1% of the variance in epistemic trust, 48.3% in booking attitude, and 55.9% in booking intention, with positive Q² values indicating strong predictive relevance. Information quality and task support significantly predicted epistemic trust and booking attitude. Booking attitude exerts the strongest direct effect on booking intention. Although epistemic trust significantly predicted booking intention, it does not significantly affect booking attitude. Mediation analysis further reveals that information quality and task support affect booking intention indirectly through booking attitude and sequentially through epistemic trust and booking attitude. These findings extend the application of the accessibility–diagnosticity framework by demonstrating that diagnostic information is first cognitively validated for credibility before shaping evaluative judgments and behavioral intentions in digital platform contexts. This highlights the distinct yet sequential roles of epistemic trust and booking attitude in OTA decision-making. Practically, the results suggest that digital travel platforms should enhance both informational quality and task-support features, as these elements jointly contribute to more favorable booking evaluations and stronger behavioral intention.