Optimal cutoff score for diagnosing generalized anxiety disorder with the Generalized Anxiety Disorder 7-item scale in people living with epilepsy: A systematic review with diagnostic test accuracy meta-analysis

Abstract

Background and Purpose The Generalized Anxiety Disorder 7-item (GAD-7) is a self-report questionnaire assessing anxiety-related symptoms experienced over the past two weeks. The GAD-7 is widely used to screen for generalized anxiety disorder (GAD), and reported optimal cutoff scores for detecting GAD in people living with epilepsy (PLWE) range between >6 and >9. This meta-analysis aims to determine the most appropriate GAD-7 cutoff score for PLWE. Methods We identified relevant studies through comprehensive searches in MEDLINE, Embase, Cochrane Library, Web of Science, and Scopus. Studies included original research examining GAD-7 accuracy for detecting GAD in adult PLWE, using structured diagnostic interviews including the Mini International Neuropsychiatric Interview as a reference standard. Only studies providing sufficient data for meta-analysis were included, including the number of PLWE with GAD, the total participant number, sensitivity, and specificity. We performed summary receiver operating characteristic curve analyses. Results Seven studies conducted in outpatient epilepsy clinics were included. The area under the curve (AUC) ranged between 0.91 and 0.96 across cutoff scores from >5 to >9. The cutoff score of >6 provided the best balance of diagnostic accuracy, with an AUC of 0.96, sensitivity of 0.95, and specificity of 0.83. Conclusions The GAD-7 cutoff score of >6 has optimal diagnostic performance for screening GAD in PLWE. These results offer valuable guidance for clinicians and researchers applying the GAD-7 questionnaire to detect GAD among PLWE, especially in geographic areas without previously validated language-specific versions.