title: Improving the cost-effectiveness of photographic screening for diabetic macular oedema: a prospective, multi-centre, UK study.
abstract: OBJECTIVE
  Retinal screening programmes in England and Scotland have similar photographic grading schemes for background (non-proliferative) and proliferative diabetic retinopathy, but diverge over maculopathy. We looked for the most cost-effective method of identifying diabetic macular oedema from retinal photographs including the role of automated grading and optical coherence tomography, a technology that directly visualises oedema.
  
  
  METHODS
  Patients from seven UK centres were recruited. The following features in at least one eye were required for enrolment: microaneurysms/dot haemorrhages or blot haemorrhages within one disc diameter, or exudates within one or two disc diameters of the centre of the macula. Subjects had optical coherence tomography and digital photography. Manual and automated grading schemes were evaluated. Costs and QALYs were modelled using microsimulation techniques.
  
  
  RESULTS
  3540 patients were recruited, 3170 were analysed. For diabetic macular oedema, England's scheme had a sensitivity of 72.6% and specificity of 66.8%; Scotland's had a sensitivity of 59.5% and specificity of 79.0%. When applying a ceiling ratio of £30,000 per quality adjusted life years (QALY) gained, Scotland's scheme was preferred. Assuming automated grading could be implemented without increasing grading costs, automation produced a greater number of QALYS for a lower cost than England's scheme, but was not cost effective, at the study's operating point, compared with Scotland's. The addition of optical coherence tomography, to each scheme, resulted in cost savings without reducing health benefits.
  
  
  CONCLUSIONS
  Retinal screening programmes in the UK should reconsider the screening pathway to make best use of existing and new technologies.
authors.affiliation: Division of Applied Health Sciences, School of Medicine & Dentistry, University of Aberdeen, Aberdeen, UK.
authors.forename: Gordon
authors.initials: G
authors.lastname: Prescott
authors.affiliation: College of Life Sciences and Medicine, University of Aberdeen, Aberdeen, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Sharp
authors.affiliation: College of Life Sciences and Medicine, University of Aberdeen, Aberdeen, UK.
authors.forename: Keith
authors.initials: K
authors.lastname: Goatman
authors.affiliation: Division of Applied Health Sciences, School of Medicine & Dentistry, University of Aberdeen, Aberdeen, UK.
authors.forename: Graham
authors.initials: G
authors.lastname: Scotland
authors.affiliation: College of Life Sciences and Medicine, University of Aberdeen, Aberdeen, UK.
authors.forename: Alan
authors.initials: A
authors.lastname: Fleming
authors.affiliation: Grampian Diabetes Research Unit, Diabetes Centre, Aberdeen Royal Infirmary, Aberdeen, UK.
authors.forename: Sam
authors.initials: S
authors.lastname: Philip
authors.affiliation: Medical Physics, NHS Grampian, Aberdeen, UK.
authors.forename: Roger
authors.initials: R
authors.lastname: Staff
authors.affiliation: Eye Out-patient Department, Aberdeen Royal Infirmary, Aberdeen, UK.
authors.forename: Cynthia
authors.initials: C
authors.lastname: Santiago
authors.affiliation: Princess Alexandra Eye Pavilion, Edinburgh, UK.
authors.forename: Shyamanga
authors.initials: S
authors.lastname: Borooah
authors.affiliation: Liverpool Diabetes Eye Centre, St. Paul's Eye Unit, Royal Liverpool University Hospital, Liverpool, UK Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, UK.
authors.forename: Deborah
authors.initials: D
authors.lastname: Broadbent
authors.affiliation: Department of Ophthalmology, Oxford Eye Hospital, Oxford, UK.
authors.forename: Victor
authors.initials: V
authors.lastname: Chong
authors.affiliation: Heartlands Hospital & Aston University, Birmingham, UK.
authors.forename: Paul
authors.initials: P
authors.lastname: Dodson
authors.affiliation: Liverpool Diabetes Eye Centre, St. Paul's Eye Unit, Royal Liverpool University Hospital, Liverpool, UK Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, UK.
authors.forename: Simon
authors.initials: S
authors.lastname: Harding
authors.affiliation: Ninewells Hospital, Dundee, UK.
authors.forename: Graham
authors.initials: G
authors.lastname: Leese
authors.affiliation: Princess Alexandra Eye Pavilion, Edinburgh, UK.
authors.forename: Roly
authors.initials: R
authors.lastname: Megaw
authors.affiliation: Queen Margaret Hospital, Dunfermline, UK.
authors.forename: Caroline
authors.initials: C
authors.lastname: Styles
authors.affiliation: National Services Division, NHS National Services, Edinburgh, UK.
authors.forename: Ken
authors.initials: K
authors.lastname: Swa
authors.affiliation: Birmingham and Black Country Diabetic Eye Screening Programme, Diabetes and Endocrinology Unit, Heartlands Hospital, Birmingham, UK.
authors.forename: Helen
authors.initials: H
authors.lastname: Wharton
authors.affiliation: Grampian Retinal Screening Programme, Aberdeen, UK.
authors.forename: John
authors.initials: J
authors.lastname: Olson
mesh_terms: D000328:Adult; D000368:Aged; D001331:Automation; D003362:Cost-Benefit Analysis; D003930:Diabetic Retinopathy / Q000175:diagnosis* / Q000191:economics; D005260:Female; D006801:Humans; D008269:Macular Edema / Q000175:diagnosis* / Q000191:economics; D008297:Male; D008403:Mass Screening / Q000191:economics* / Q000379:methods; D008875:Middle Aged; D010781:Photography / Q000191:economics* / Q000379:methods; D011446:Prospective Studies; D058996:Quality Improvement / Q000191:economics; D019057:Quality-Adjusted Life Years; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence / Q000191:economics / Q000379:methods; D006113:United Kingdom
keywords: Diagnostic tests/Investigation; Macula; Retina