Stanford OCT AMD classification shows excellent intergrader agreement in diagnostic development study

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medRxiv Published April 3, 2026 Medically reviewed April 26, 2026 Study authors: Yeh, T.-C.; Lin, J. B.; Mruthyunjaya, P.; Leng, T.; DeBoer, C.; Sepah, Y.; Almeida, D. R.; Mahajan, … DOI ↗ By Dr. Lars van Dijk, PhD · Surgical, Procedural & Diagnostic

Key Takeaway

Consider SOAC as a technically reliable OCT classification framework requiring further validation for clinical use.

This diagnostic classification development study evaluated the newly proposed Stanford OCT Based AMD Classification (SOAC) in 108 patients (109 eyes). Researchers applied SOAC to spectral domain optical coherence tomography scans to categorize AMD stages and assess intergrader agreement. The distribution of AMD staging based on SOAC was: normal aging in 9 patients (8.3%), early AMD in 16 (14.7%), intermediate AMD in 32 (29.4%), neovascular AMD in 18 (16.5%), geographic atrophy in 20 (18.3%), and combined neovascular AMD and geographic atrophy in 14 (12.8%).

The primary finding was excellent intergrader reliability for SOAC, with a weighted kappa value of 0.95 (95% CI: 0.92 to 0.98). This indicates strong agreement between graders when applying the new classification system to OCT scans. The study did not report safety or tolerability data, as it focused on classification reliability rather than therapeutic intervention.

Key limitations include the absence of diagnostic accuracy data compared to a reference standard, no reported clinical outcomes associated with the classification, and no longitudinal validation. The study setting and funding sources were not reported. In practice, SOAC provides a standardized, OCT-based framework for AMD grading that demonstrates high intergrader agreement, potentially supporting consistent disease staging and facilitating integration across clinical studies. However, clinicians should recognize this represents initial technical validation requiring further diagnostic accuracy and clinical utility assessment.

Study Details

Sample sizen = 108

EvidenceLevel 5

PublishedMar 2026

View Original Abstract ↓

Background and Objective As optical coherence tomography (OCT) has enabled the identification of an expanding set of age related macular degeneration (AMD) risk biomarkers and become central to routine clinical practice, there remains a need for a simplified grading scheme that allows physicians to communicate and synchronize AMD grading directly from standard OCT imaging rather than relying on traditional color fundus imaging. This study aims to establish a standardized OCT based AMD classification that balances diagnostic accuracy with practicality for use across clinical and research settings. Patients and Methods Spectral domain optical coherence tomography scans were independently graded by two retinal specialists following the newly proposed Stanford OCT Based AMD Classification (SOAC). Discrepancies were adjudicated by a third independent retinal specialist. Intergrader agreement was assessed using weighted kappa coefficients. Results Among the 109 eyes from 108 patients, AMD staging based on SOAC was distributed as follows: normal aging in 9 patients (8.3%), early AMD in 16 (14.7%), intermediate AMD in 32 (29.4%), neovascular AMD (nAMD) in 18 (16.5%), geographic atrophy (GA) in 20 (18.3%), and combined nAMD and GA in 14 (12.8%). The overall intergrader agreement demonstrated robust consistency, with a weighted kappa value of 0.95 (95% CI: 0.92 to 0.98), signifying excellent intergrader reliability and reinforcing the validity of SOAC. Conclusion SOAC provides a standardized, OCT based framework for AMD grading that demonstrates high intergrader agreement. By enabling consistent classification from commonly acquired OCT scans, SOAC supports reliable disease staging and facilitates integration across clinical studies and translational research. As imaging and molecular data continue to expand, SOAC can serve as a common OCT based reference for phenotype refinement and longitudinal AMD studies.