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Abstract #15846 Published in IGR 2-3
Utility of predictive equations for estimating the prevalence and incidence of primary open-angle glaucoma in the UK
Minassian DC; Reidy A; Coffey M; Minassian ABritish Journal of Ophthalmology 2000; 84: 1159-1161
AIMS: To assess the Tuck-Crick and the Quigley-Vitale predictive regression equations against fresh independent real world data for estimating the prevalence of primary open-angle glaucoma (POAG) in the UK. To apply the equations to the elderly population of England and Wales, for which there is sample survey data on glaucoma, and demographic data. METHODS: Directly measured actual prevalence of POAG in a population sample of 1530 people was compared with the predicted prevalence derived by applying the Tuck-Crick and the Quigley-Vitale equations to the sample data. The two equations were applied to the demographic data of the population to project POAG prevalence and to derive five-year cumulative incidence for the elderly population. These were compared with estimates derived from the local survey data. RESULTS: The actual directly measured prevalence of POAG in the local sample was 3.01%. The Tuck-Crick estimate was 2.74% (difference 0.27%), and the Quigley-Vitale was 3.50% (difference -0.49%). The three methods-projection from local survey data, Tuck-Crick, and Quigley-Vitale-gave point estimates of 2.85% (228,526 cases), 2.71% (217,375 cases), and 3.50% (280,364 cases), respectively, for the prevalence of POAG in the elderly population of England and Wales (8,008,705 people aged 65 or older). Calculation of incidence from age specific prevalence gave the following results: the numbers of new cases of POAG expected (five-year cumulative incidence) in the elderly population were 71,146 and 94,485 for methods 2 and 3, respectively. CONCLUSIONS: The Tuck-Crick predictive equation performed well when applied to fresh (independent) actual data from a local sample survey using a particular definition for POAG, and its usefulness for estimation of prevalence of POAG in England and Wales has been demonstrated. The work on development of predictive equations has been very promising and further refinements could be made when more fresh survey data become available.
Dr. D.C. Minassian, Institute of Ophthalmology, UCL, Bath Street, London EC1V 9EL, UK
Classification:
1.1 Epidemiology (Part of: 1 General aspects)
