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Enrolling by invitation NCT07208838

Validation of DDIVAT Digital Optotypes for Distance Visual Acuity Testing Among the Bulgarian Population

— Observational Vision Screening

For patients and families

In plain language

An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.

What is being studied
The protocol lists: To test visual acuity in 150 Bulgarian patients over 18 years of age using Snellens visual acuity chart and DDIVAT optotypes.
Who it may be relevant to
Registry conditions: Vision Screening. Basic parameters: from 18 years · All.
What needs checking
Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
Where it takes place
Bulgaria
Next step
Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →

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Overview

To compare distance visual acuity in Bulgarian patients over 18 years of age using two different methods - the Snellen method and the DIDIVAT digital online optotypes. For the purpose of this study, it is planned to examine native visual acuity (with and without prescribed optical correction), without additional mydriasis in both ways, of 150 Bulgarian patients (75 women and 75 men) over 18 years of age, hospitalized in a university eye clinic at St. George University Hospital and healthy volunteers willing to participate in the study. The statistical analysis that will be performed will aim to compare whether the two methods for determining distance visual acuity are identical in results, as well as to validate the application for the Bulgarian population.The study is expected to prove that the distance visual acuity of patients examined by both methods is identical.

Interventions

  • Diagnostic test To test visual acuity in 150 Bulgarian patients over 18 years of age using Snellens visual acuity chart and DDIVAT optotypes
    The study compares newly developed visual acuity test (DDIVAT) with standart method for visual acuity testing used worldwide

Primary outcome measures

  • The study is expected to prove that the distance visual acuity of patients examined by both methods is identical. [Time frame: 12 monts]

Eligibility criteria

Inclusion criteria

  • Bulgarian speaking patients (75 women and 75 men) over 18 years of age, hospitalized in a university eye clinic at St. George University Hospital and healthy volunteers willing to participate in the study.

Exclusion criteria

  • Patients of less than 18 years of age.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Observational model
Cohort

Study locations

Bulgaria · 1 center
  • Medical University Plovdiv — Plovdiv

Publications

  • Bakirtzis M, Michaleakou E, Martidou ME, Lahana E, Kostagiolas P, Niakas D, Labiris G. Visual Acuity Screening of Refugees and Immigrants with a Web-Based Digital Test: A Pilot Study. Acta Medica (Hradec Kralove). 2024;67(3):79-86. doi: 10.14712/18059694.2025.2. PMID 39963735
  • Labiris G, Panagiotopoulou EK, Duzha E, Tzinava M, Perente A, Konstantinidis A, Delibasis K. Development and Validation of a Web-Based Reading Test for Normal and Low Vision Patients. Clin Ophthalmol. 2021 Sep 22;15:3915-3929. doi: 10.2147/OPTH.S314943. eCollection 2021. PMID 34588763
  • Labiris G, Panagiotopoulou EK, Chatzimichael E, Tzinava M, Mataftsi A, Delibasis K. Introduction of a digital near-vision reading test for normal and low vision adults: development and validation. Eye Vis (Lond). 2020 Oct 22;7:51. doi: 10.1186/s40662-020-00216-0. eCollection 2020. PMID 33102611
  • Labiris G, Panagiotopoulou EK, Delibasis K, Duzha E, Bakirtzis M, Panagis C, Boboridis K, Mokka A, Balidis M, Damtsi C, Ntonti P. Validation of a web-based distance visual acuity test. J Cataract Refract Surg. 2023 Jul 1;49(7):666-671. doi: 10.1097/j.jcrs.0000000000001176. PMID 36853857

Identifiers

NCT: NCT07208838 · PlovdivMUDDIVAT

Primary sources (government registries)

View this study on ClinicalTrials.gov ↗