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Cup-to-disc ratios of Aboriginal and non-Aboriginal youths
1Patrick Gerry Optometrists, Brisbane, Queensland, Australia. pat@pgo.com.au
Background:
The determination of the cup-to-disc ratio (C/D) is a standard procedure in an eye examination and is pivotal in the diagnosis of glaucoma. Determining the size of the C/D ratios of different races of young people may be helpful in determining the genetically predetermined differences between Aboriginal and non-Aboriginal people. The aim of this study was to determine whether there is a statistically significant difference in the average C/D ratios of young Aboriginal and non-Aboriginal people.
Methods:
The overall average C/D ratios of 104 subjects aged between five and 23 years were compared for two age-matched groups by stereoscopic indirect ophthalmoscopy. Differences between the overall average C/D ratios of the two groups were assessed for significance using an unpaired Student's t test.
Results:
While the range of C/D ratios within each group was the same (zero to 0.7), there was a statistical difference (p < 0.001) between the overall average C/D ratios of the Aboriginal (C/D = 0.295) and non-Aboriginal (C/D = 0.159) groups.
Conclusions:
Results indicating a difference between the overall average C/D ratios between Aboriginal and non-Aboriginal young people may have implications for initial assessments of glaucoma in patients of any age.
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