Mental Health Screening Tools for Anxiety and Depression in Post-Secondary Students: A Literature Review to Inform Digital Intervention Development (Preprint)

BACKGROUND Post-secondary students experience increasingly high rates of mental health challenges. Evidence-supported digital mental health interventions (DMHIs) could form part of an integrated, sustainable prevention and early intervention approach suited for university students. Screening tools like the two- and nine-item Patient Health Questionnaire (PHQ-2, PHQ-9) and the two- and seven-item Generalized Anxiety Disorder questionnaire (GAD-2, GAD-7) could inform individualized signposting to appropriate support resources and services, yet their validation has been largely in general adult populations, raising concerns about their suitability in post-secondary student contexts. OBJECTIVE To bridge this gap, this literature review aims to summarize the psychometric properties of commonly used screening tools, particularly the PHQ-9, PHQ-2, GAD-7, and GAD-2, across student and general adult populations. Proper use and population specific screening thresholds are critical to develop evidence-based DMHIs that accurately assess, monitor, visualize, and respond to student mental health challenges. METHODS Following PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines, a search of peer-reviewed literature across PubMed, Web of Science, and PsychINFO yielded 82 studies, 49 of which were selected for data extraction and analysis. Studies were clustered into Group 1 (student populations) and Group 2 (general adult populations). This review extracted optimal screening thresholds along with sensitivity, specificity, area under the curve, and predictive values. RESULTS Psychometric properties varied between student and general adult samples. Among students, GAD-2 showed the highest sensitivity (94.2%) and highest specificity (85.2%), while PHQ-2 demonstrated weaker specificity (66.5%). Optimal screening thresholds for student populations were generally equal or lower than those used in general adult settings, especially for the GAD-7 (cut-off: 6 vs. 10). Missing and inconsistent reporting on ethnicity and gender differences limited equity-oriented analysis. CONCLUSIONS Applying general adult screening thresholds may compromise accuracy and care equity in student populations. Student-calibrated screening thresholds are important to improve screening precision for DMHI utility and effectiveness.