Screening and monitoring of diabetic retinopathy in community care: the effectiveness of single-field vs multi-field fundus photography

Purpose: This study aimed to evaluate the effectiveness of single-field fundus photography for diabetic retinopathy (DR) screening and monitoring versus six-field imaging in community settings. Methods: Adults aged ≥30 years with type 2 diabetes from 15 communities in Northeast China were recruited for this prospective cohort study (n=2006 at baseline and n=1456 at follow-up). Participants underwent both single-field and six-field digital fundus photography at baseline and follow-up visits (mean duration of 21.2±3.2 months). Photographs were graded using international standards. Agreement in DR severity grading, referral recommendations, and detection of DR progression were compared between single-field and six-field fundus photography. Results: Single-field grading showed substantial agreement with multi-field grading in classifying DR severity (81.9% identical at baseline, 80.6% at follow-up, Gwet's AC1 0.79 and 0.77). For referring eyes with moderate non-proliferative DR or worse, single-field grading had ∼70% sensitivity and 100% specificity compared to six-field grading. Single-field grading identified 74.9% or 79.7% of eyes progressing or regressing by six-field grading, respectively. Conclusions: Single-field fundus photography demonstrated reasonable effectiveness for DR screening and monitoring in a community setting, supporting its use for improving access to DR detection. However, reduced sensitivity compared to multi-field imaging should be acknowledged.