Background/Aims Ongoing and recent clinical trials for geographic atrophy (GA) have used different outcomes. The goal of this study was to identify a core outcome set (COS) important for patients, clinicians and researchers, and to propose the use of COS in the design of future GA trials.

Methods Five-component project including: Delphi method with patients and experts, focus groups and interviews with patients, relatives and workers supporting patients. Three hundred and one patients (301) with age-related macular degeneration participated in round 1 of a Delphi exercise. Most subjects had GA; 183 patients (61%) were females and the median (range) age was 77 (50–99) years. In round 2, of the 301 of the first round, 100 participants were randomly selected of whom 76 agreed to take part. In a parallel Delphi exercise, panellists comprised a mix of non-clinical scientists and clinicians (43 in the initial and 21 in the final round). In addition, interviews and focus groups consisting of patients (n=20), family members (n=4) and support workers (n=5) were undertaken.

Results Core outcomes identified as important for age-related macular degeneration trials were the health of the outer retina, multimodal estimation of lesion size, reading speed, best corrected distance and near acuity, low luminance visual acuity, patient reported visual performance and safety.

Conclusion This study identified a set of core outcomes that should be used in GA trials. The COS include patient-reported outcome measures, near visual acuity, reading speed and assessment of the outer retina.