According to a recent study, 30%.
A telemedicine screening program was conducted between 2012-2016 to determine the usefulness in detecting diabetic retinopathy. Patients with type 2 diabetes were referred for fundus photos using the Optos. Of the almost 5,000 patients screened, the study found that nearly 30% of them had diabetic retinopathy. The majority of those patients had mild retinopathy but 30% were scheduled for an exam within 1 to 6 months due to the findings. (via)
