The hidden burden: Sub-threshold mental symptoms, abnormal illness behavior, and their association with quality of life among college students

Sub-threshold mental symptoms are highly prevalent among college students and are cross-sectionally associated with significant quality of life reduction. Specifically, our findings support a transdiagnostic intervention approach targeting stress load regulation-rather than symptom-specific interventions-as more clinically relevant for this population. Thus, colleges should prioritize stress-focused preventive strategies to mitigate symptom progression and functional impairment in sub-threshold students. Notably, abnormal illness behavior mediates the association between symptoms and quality of life only in the above-threshold group, indicating that colleges should tailor interventions differently for sub- versus above-threshold students.