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Prevalence of refractive errors among school students in Iraq - A systematic review and meta-analysis
Hassan A Aljaberi1, I R Ali1, Zaydoon Tariq M Noori2
1Optics Techniques Department, College of Health and Medical Techniques, Al-Mustaqbal University, Hillah 51001, Iraq.
Purpose:
This research aimed to thoroughly examine and meta-analyse statistical information about the prevalence of refractive error in Iraq.
Methods:
To discover every pertinent Iraqi epidemiological study from March 2014 to March 2024, Scopus, Science Direct, Google Scholar, Embase, PubMed, and the Cochrane Library were searched and reviewed. The Iraqi refractive error rate was interesting. The Comprehensive Meta-Analysis Software received unprocessed events and sample sizes for effect size calculations.
Results:
A meta-analysis was undertaken by pooling data from 10 studies. The fixed effects model indicates an estimated effect size of 29.8% (95% CI: 28.6-30.9%). However, the statistical measures of heterogeneity (Q-value p < 0.001; I2 = 98.707) showed significant heterogeneity among the studies, which indicates that a random-effects model should be used. The random effects model suggests that the prevalence of refractive error in the Iraqi population is predicted to be 27.6% (95% CI: 18.9-38.5%). The most common refractive defect was myopia, found in 35.1% of cases (95% CI: 24.9-46.8%). Astigmatism was the second most prevalent, affecting 32.2% (95% CI: 19.1-49.0%), followed by hyperopia in 23.9% (95% CI: 16.0-34.2%).
Conclusions:
Current estimate of refractive error prevalence in Iraq may be conservative of this condition's burden. Nevertheless, this corresponds to a minimum of 8 to 18 million individuals in Iraq who have a refractive error. Due to study variability, wide estimate ranges, and random effects, more research and reliable sources are needed to obtain more accurate results.
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