OBJECTIVES: In order to conduct a multi-center retrospective chart review, with the purposes of assessing resource utilization and the multiple costs associated with disease progression, a glaucoma staging system (GSS) was developed. Since no universally accepted GSS exists, particularly one that takes into account economic considerations, we tested a modified system to allow for unambiguous stage assignment for all patients and to evaluate the economic impact of progressing disease severity. METHODS: A review of currently developed GSSs was conducted and the Bascom Palmer GSS was selected as most adaptable for economic analyses. A modified Delphi panel of physicians specializing in glaucoma treatment suggested modifications to the system. Consideration was given to practical use in retrospectively staging patients using clinical parameters available in glaucoma charts, with the end goal of assessing the economic impact of treating glaucoma. Modifications were made to ensure defined stages encompassed a complete severity range from pre-diagnosis to complete blindness. The revised GSS was pre-tested on 30 charts at one participating center in a retrospective chart review study and final modifications were made to assure certainty in patient classification. RESULTS: The final GSS comprises six stages based principally on visual field parameters. End-stage disease was defined based on poor visual acuity and inability to perform visual fields. The finalized GSS was successfully applied to a new group of randomly selected glaucoma charts. The instrument was able to classify all identified glaucoma patients from normal to end-stage disease, and facilitated resource utilization abstraction by individual stage. CONCLUSIONS: An improved GSS to track progression was designed which allows staging of patients from historical chart data. This GSS may be used to monitor long-term progression and is a useful tool for the purposes of assessing the economic impact of glaucoma progression in categorical stages. This GSS needs to be further tested prospectively to determine its ultimate utility in economic evaluations.