title: Quality assurance in diabetic retinal screening in South Africa.
abstract: BACKGROUND
  Diabetic retinopathy (DR) is an important biomarker for microvascular disease and blindness. Digital fundus photography is a cost-effective way of screening for DR. Access to DR screening is difficult for many South Africans with diabetes.
  
  
  OBJECTIVE
  To perform external quality assurance (EQA) on graders registered in the Ophthalmological Society of South Africa DR screening programme.
  
  
  METHODS
  Graders registered on the South African (SA) Diabetic Register website were invited to participate in the study. The Scottish EQA software system was used to enable on-line grading of 100 retinal photographs. Expert National Health Service graders provided the consensus expert grading for the image set.
  
  
  RESULTS
  Two hundred and sixty-one participants completed the EQA process, including nine ophthalmologists, 243 optometrists, and nine other graders. A wide range of outcomes were demonstrated, with a mean sensitivity of 0.905 (range 0.286 - 1.000) and mean specificity of 0.507 (0.000 - 0.935). The mean diagnostic odds ratio was calculated to be 12.3 (range 0.147 - 148.2).
  
  
  CONCLUSIONS
  This is the first quality assurance study conducted with SA healthcare professionals. The outcomes are of interest to all stakeholders dealing with the diabetes epidemic. The disparity in grader performance indicates room for improvement. The results demonstrate a high referral rate to ophthalmology, suggesting that on average graders are performing safely, but with a high number of inappropriate referrals.
authors.affiliation: The Eye Centre, East London, Eastern Cape, South Africa; Department of Ophthalmology, Faculty of Health Sciences, Walter Sisulu University, Umtata, Eastern Cape, South Africa. dr@eyecentre.co.za.
authors.forename: Steve
authors.initials: S
authors.lastname: Cook
authors.forename: Roger T
authors.initials: RT
authors.lastname: Staff
authors.forename: Keith A
authors.initials: KA
authors.lastname: Goatman
authors.forename: John A
authors.initials: JA
authors.lastname: Olson
mesh_terms: D000328:Adult; D003930:Diabetic Retinopathy / Q000175:diagnosis*; D005104:Expert Testimony; D005260:Female; D005451:Fluorescein Angiography / Q000379:methods*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods / Q000592:standards; D008297:Male; D008403:Mass Screening / Q000379:methods / Q000592:standards; D020380:Needs Assessment; D011785:Quality Assurance, Health Care; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013019:South Africa