Hoffmann EM, et al. - In this investigation involving 31 patients (42 eyes) after trabeculectomy, researchers contrasted the MaBAGS (Mainz Bleb Appearance Grading System), a classification system for filtering blebs with other classification systems (MBGS/Moorfields Bleb Grading System, IBAGS/Indiana Bleb Appearance Grading Scale) in reference to reliability and usability and compare it to grading by bleb photographs. They performed statistical analysis to determine the agreement between the observers using intraclass correlation coefficients. According to results, regarding vascularity indices, Seidel test and transparency, excellent and good levels of agreement were found with MaBAGS. Findings revealed that MaBAGS exhibits good reproducibility. Using such a grading system enhances the accuracy of a highly variable clinical finding description. The authenticity of grading by slit-lamp examination exceeds that of grading on photographs.