Student Theses, Dissertations and Capstones

Document Type

Thesis - NSU Access Only

Degree Name

Master of Science (M.S.) in Clinical Vision Research

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College of Optometry

First Advisor

Chris Woodruff

Publication Date / Copyright Date



Nova Southeastern University. College of Optometry.


Background: The World Health Organization estimates that there are 517 million people in the world who are visually impaired due to uncorrected presbyopia. Equal sphere ready-made bifocal and single vision reading spectacles are an inexpensive alternative to custom made spectacles. Methods: A visual satisfaction questionnaire was administered before patients were examined at an outreach clinic and again after ready-made bifocals or reading spectacles were dispensed. The results of both sets of questions along with presenting acuities, corrected acuities, refractive data, and willingness to pay were analyzed. Results: There was an unmet need of 38% (of the 338 subjects that needed glasses only 208 had them). There was no gender bias; the unmet need was higher in the rural areas (47% rural, 36% urban). Those who could not read were 3.4 times less likely to have the glasses they needed than the literate. Unmet need decreased with every level of education. Those without any schooling showed 77% prevalence of unmet need and those with university education had an unmet need rate of 32%. Ready-made spectacles were dispensed to 89.5% of those examined. The ready-made bifocals were very well accepted, with the percentage of subjects giving the highest satisfaction rating improving from a presenting value of 11% to 89.4% with the bifocals at distance and from 6.6% to 89.4% at near. Distance visual acuity of 20/40 or better improved from the presenting value of 60% to 84.5% and near vision of 20/40 or better improved from the presenting value of 44% to 97%. With ready-made single vision readers, functionally good near vision (20/40 or better) improved from a presenting value of 38% to 97%. The highest ranking for near satisfaction improved from 6.3% to 86.6%. The subjects indicted that they would be willing to pay US$18.39 to replace the bifocals and US$16.67 to replace the readers. Conclusion: There is a high unmet need for vision correction in the population over age 35 in Nicaragua. Dissatisfaction with distance and near vision is very high. Although custom made glasses are ideal, ready-made bifocals and ready-made single vision readers are an acceptable and affordable alternative.




Health and environmental sciences, Presbyopia, Ready-made spectacles, Refractive error, Spectacles, Vision 2020, Visual acuity



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