Development of a Validated Chart for Intermediate Vision Assessment

Study Overview
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Brief Summary
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Development of a validated computer-based instrument (software program) for the assessment of intermediate visual acuity.

Detailed Description
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Development of a validated computer-based instrument (software program) for the assessment of intermediate visual acuity (IVA). It is known that no validated method for the evaluation of IVA exists. Primary objective of the study is to validate a specific computer-based chart (optotype) that will enable: a) comparative studies among different groups of presbyopic patients with refractive errors (ie. myopia, hyperopia, and/or astigmatism), and, b) assessment of the efficacy of surgical refractive procedures (ie. LASIK) on presbyopic patients. Intermediate Visual acuity chart is similar to the prevalent Jaeger chart. It consists of short blocks of text in various type sizes.The computer screen is set at a specific reading distance (1 meter) and the patient is asked to read the passage with the smallest type he/she can see. According to the smallest text he/she can read, IVA is classified from IVA1 (which is considered the equivalent of 20/20 distance visual acuity) to IVA5 Validation of the computer-based IVA chart will be done by correlating the results of the IVA chart to the corresponding ones from the validated 20/20 distant and Jaeger near visual acuity charts, in a random sample of study participants with different refractive errors and different near and distant visual acuities.

Official Title
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Development of a Validated Chart for Intermediate Vision Assessment

Conditions
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Myopia, Hyperopia, Presbyopia, Astigmatism

Intervention / Treatment
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* Other: Intermediate Visual acuity (IVA) assessment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: native Greek participants or foreigners with perfect knowledge (verbal and written) of Greek language Exclusion Criteria: glaucoma or suspicion for glaucoma, corneal disease or suspicion for corneal disease fundus disease or suspicion for fundus disease pregnancy or nursing, underlying autoimmune disease mental or neurologic disease

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 20/20ND group<br>This group will have 20/20 visual acuity both in distant and near. | Other: Intermediate Visual acuity (IVA) assessment<br>* Intermediate visual acuity (IVA) will be assessed with the Intermediate Visual acuity chart which is similar to the prevalent Jaeger chart. It consists of short blocks of text in various type sizes.The computer screen is set at a specific reading distance (1 meter) and the patient is asked to read the passage with the smallest type he/she can see. According to the smallest text he/she can read, IVA is classified from IVA1 (which is considered the equivalent of 20/20 distance visual acuity) to IVA5<br>|
| 20/20D group<br>This group will have 20/20 distant visual acuity and variable near visual acuity. | Other: Intermediate Visual acuity (IVA) assessment<br>* Intermediate visual acuity (IVA) will be assessed with the Intermediate Visual acuity chart which is similar to the prevalent Jaeger chart. It consists of short blocks of text in various type sizes.The computer screen is set at a specific reading distance (1 meter) and the patient is asked to read the passage with the smallest type he/she can see. According to the smallest text he/she can read, IVA is classified from IVA1 (which is considered the equivalent of 20/20 distance visual acuity) to IVA5<br>|
| 20/20N group<br>This group will have 20/20 near visual acuity and variable distant visual acuity. | Other: Intermediate Visual acuity (IVA) assessment<br>* Intermediate visual acuity (IVA) will be assessed with the Intermediate Visual acuity chart which is similar to the prevalent Jaeger chart. It consists of short blocks of text in various type sizes.The computer screen is set at a specific reading distance (1 meter) and the patient is asked to read the passage with the smallest type he/she can see. According to the smallest text he/she can read, IVA is classified from IVA1 (which is considered the equivalent of 20/20 distance visual acuity) to IVA5<br>|
| s20/20ND group<br>This group will have variable near and distant visual acuity (both less than 20/20) | Other: Intermediate Visual acuity (IVA) assessment<br>* Intermediate visual acuity (IVA) will be assessed with the Intermediate Visual acuity chart which is similar to the prevalent Jaeger chart. It consists of short blocks of text in various type sizes.The computer screen is set at a specific reading distance (1 meter) and the patient is asked to read the passage with the smallest type he/she can see. According to the smallest text he/she can read, IVA is classified from IVA1 (which is considered the equivalent of 20/20 distance visual acuity) to IVA5<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intermediate Visual Acuity (IVA) | Number of participants that their intermediate visual acuity measured with the intermediate visual acuity chart will be statistically correlated with distant visual acuity (measured by 20/20 chart) and near visual acuity (measured by Jaeger chart) | 6 months |