Agreement and Diagnostic Test Accuracy on Grading Diabetic Retinopathy Using Fundus Photographs by Allied Medical Personnel at a Community Diabetic Retinopathy Screening Program in Nepal

ABSTRACT

Purpose: Diabetic retinopathy (DR) is a leading cause of blindness in low- and middle-income countries. This study aims to assess the agreement and diagnostic test accuracy of DR grading using fundus photographs by the allied medical personnel (AMP) as compared to ophthalmologist at DR screening program.

Methods: Two 45 degree disc-centred and macula centred fundus photographs captured using digital fundus camera from 1344 eyes were graded by six AMP twice at three months and six months of training. DR grading was done using Early Treatment Diabetic Retinopathy Study criteria. Retina specialist grading was taken as the reference standard. Percentage agreement using kappa coefficient (k) and diagnostic test accuracy were assessed.

Results: Intra-rater agreement of most AMP was almost perfect for detection of any DR and vision-threatening diabetic retinopathy (VTDR) at three and six months. Inter-rater agreement at 3 months at second grading was substantial for any DR (k = 0.62; 95% confidence interval (CI): 0.67–0.68) and VTDR (k = 0.63; 95% CI: 0.47–0.75). Inter-rater agreement in 6 months at second grading was also substantial for any DR (k = 0.66; 95% CI: 0.61–0.71) and VTDR (k = 0.64; 95% CI: 0.52–0.75). The sensitivity and specificity for any DR at second grading in 3 months was 94.99% and 63.97% and at 6 months was 95.55% and 66.91%, respectively.

Conclusion: The inter-rater agreement of AMP as compared to ophthalmologists for any DR or VTDR was substantial at both 3 and 6 months. AMP can support as first-level DR graders for timely referral and treatment of VTDR.

KEYWORDS:

• Allied medical personnel
• intra-rater agreement
• inter-rater agreement
• ophthalmologist
• diabetic retinopathy
• vision-threatening diabetic retinopathy
• screening

Acknowledgments

The authors acknowledge “The Fred Hollows Foundation, Australia and World Diabetes Foundation” for financial support of this study. We would like to acknowledge collaborating public hospitals “Bir Hospital, Gangalal National Heart Center, and Patan Hospital” for all the support for this study, conducted as a part of a diabetic retinopathy project under the Tilganga Institute of Ophthalmology. Paul S. Bernstein, MD, PhD helped edit the manuscript.

Financial support

The Fred Hollows Foundation, Australia and World Diabetes Foundation

Conflicts of interest

None of the authors have any proprietary interests or conflicts of interest related to this submission.

Statement

This submission has not been published anywhere previously and that it is not simultaneously being considered for any other publication.