Presentation on theme: "RAPID ASSESSMENT OF REFRACTIVE ERROR (RARE). Uncorrected Refractive Error (URE) “The Crisis” URE is most common cause of Visual impairment (VI) worldwide."— Presentation transcript:
Uncorrected Refractive Error (URE) “The Crisis” URE is most common cause of Visual impairment (VI) worldwide and 2 nd most common cause of blindness 1,2 URE drives children and adults further into poverty: 3 −Limits opportunities to education −Employment −Seriously impacts quality of life and productivity Link between poverty and VI due to URE places heavy economic burden on individuals families affected nations
Historical Situation Paucity of Data Refractive data elicited through: −RESC studies From community to school Children only −Conventional Population based studies Prohibitively expensive High level of expertise Few and far between Lag between completion and Program implementation timelines
CONTEXT SETTING Why and where do we need data −National level Planning Evaluation Awareness Advocacy −Regional level Advocacy Establish priorities for investment in regions
Target Group RARE studies used to assess prevalence of URE, presbyopia, spectacle coverage, and barriers to uptake of services for refractive errors and presbyopia 5 Studies are focused on: Younger age groups more affected by RE Presbyopia 15-49 years
Definitions ConditionDefinition Visual Impairment Binocular Presenting VA<6/12 in the better eye Uncorrected Refractive Error (URE) Presenting VA<6/12 but improving ≥6/12 with pinhole Presbyopia Binocular near vision < N8 at 33-35cms
DefinitionDescription URE (Unmet need) Unaided VA <6/12 but improving to 6/12 or better with pinhole and no spectacles Uncorrected Presbyopia (Unmet need) Binocular Unaided near vision 35 years with no distance VI and no spectacles Corrected RE (Met need) Unaided VA<6/18 but improved to 6/18 or better with spectacles Corrected Presbyopia (Met need) Unaided near vision < N8, but improved to N8 or better with their spectacles Definitions
EquipmentPurpose Snellen chart (E, Alphabet optotypes) Distance Visual Acuity Measuring tape or String Measure testing distance: subject and chart Multiple pinhole occluder Presenting VA, if VA<6/12 N notation chartNear vision Torch lightExternal examination Ready made spectacles (+1.0 to +3.0 Ds) Best corrected near vision assessment in individuals with presbyopia RARE Toolkit
OUTPUTS OF RARE STUDIES What is the impact of gathering this information?....
References 1.Resnikoff S, Pascolini D, Mariotti S, Pokharel P. Global magnitude of visual impairment caused by uncorrected refractive errors in 2004. Bull World Health Organ 2008;86:63-70. 2.Holden BA, Fricke T, Ho S, Wong R, Schlenther G, Cronje S, et al. Global vision impairment due to uncorrected presbyopia. Arch Ophthalmol 2008;126:1731-9. 3.Fricke TR, Holden BA, Wilson DA, Schlenther G, Naidoo KS, Resnikoff S and Frick KD. Global cost of correcting vision impairment from uncorrected refractive error. 4.Naidoo KS, Wallace DB, Holden, BA, Minto H, Faal HB, Dube P. The challenge of uncorrected refractive error: driving the agenda of the Durban Declaration on refractive error and service development. Clin Exp Opt 2010: 93(3): 131-136. 5.Marmamula S, Keeffe JE, Rao GN. Uncorrected refractive errors, presbyopia and spectacle coverage: Results from a Rapid Assessment of Refractive Error survey. Ophthalmic Epidemiology 2009;16:269-74. 6.Marmamula et al. Population-based cross-sectional study of barriers to utilisation of refraction services in South India: Rapid Assessment of Refractive Errors (RARE) Study. British Medical Journal.
Acknowledgements Pirindha Govender Brien Holden Vision Institute (Public Health Division) – Research Department