Long-Term Outcomes and Predictors of Response to Anti-VEGF Therapy for Diabetic Macular Edema in Clinical Practice

This protocol provides a standardized methodology for evaluating the 24-month effectiveness and safety of anti-vascular endothelial growth factor (anti-VEGF) therapy in center-involved diabetic macular edema (DME) using real-world clinical data. The procedure involves a structured electronic medical record (EMR) screening algorithm based on ICD-10 codes, followed by manual clinical verification. Patients are categorized into a class-level anti-VEGF treatment group (receiving ranibizumab, aflibercept, or conbercept) or a non-biologic control group (focal/grid laser or observation). To mitigate non-random allocation bias inherent in retrospective data, inverse probability of treatment weighting (IPTW) is employed to balance baseline demographic and tomographic covariates across groups. The methodology specifies standardized visual acuity assessment using ETDRS charts and detailed OCT acquisition parameters to ensure longitudinal data consistency. By analyzing visual and anatomical trajectories alongside structural biomarkers, such as the disorganization of the retinal inner layers (DRIL), this approach provides a reproducible framework for assessing long-term outcomes in routine clinical settings. While acknowledging the limitations of a single-center retrospective design, these methods offer critical evidence to help characterize the efficacy-effectiveness gap and optimize personalized management strategies for DME.