DDVIT: A Web-based Digital Distance Visual Acuity Test

Sponsor

Democritus University of Thrace (Other)

Overall Status

Recruiting

CT.gov ID

NCT04756596

Collaborator

University of Thessaly (Other)

300

Enrollment

Locations

16.9

Anticipated Duration (Months)

150

Patients Per Site

8.9

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Primary objective of this study is the development and validation of a web-based application for the examination of the distance visual acuity of normal- and low-vision patients.

Condition or Disease	Intervention/Treatment	Phase
Refractive Errors Low Vision Vision Disorders	Diagnostic Test: DDVIT testing Diagnostic Test: ETDRS testing

Detailed Description

Present study aims to develop and validate a web-based digital distance visual acuity test (Democritus Distance Vision Test - DDVIT). DDVIT is an application, which will be easily accessed through a simple internet connection. This application will provide the possibility of a simple but reliable examination of patients, establishing a commonly accepted way of measuring the distance visual acuity among rural doctors, general practitioners and ophthalmologists.

Specifically, present study aims to develop a new online distance visual acuity test (DDVIT) according to the standards of the Early Treatment Diabetic Retinopathy Study (ETDRS) test and to evaluate the level of agreement between the two visual acuity tests, as well as the test-retest reliability of the online DDVIT visual acuity test.

The first part of the study is the development of the online visual acuity test (letters, numbers, symbols) including the following smart features:

Adjustment of the font size according to the size of the computer screen used for the examination
Real time calculation of the patient-screen distance through a face detection system
Automatic calculation of the reading time of each line (each logMAR)
Entering the number of patient's reading errors for each line
Automatic calculation of the visual acuity in the following score units:

Number of Letters (max 85)
Visual Acuity Score (max 100)
logMAR
Decimal
Snellen Fraction

The calculation of various reading parameters resulting from the aforementioned features (visual acuity score in different units, reading duration (in sec) and number of errors for each slide (line), patient-screen distance for each slide) will be performed after the end of the examination. Except for the html format, a file in the format of Microsoft Excel and Pdf are also generated.

The second part of this study is the clinical validation of the DDVIT visual acuity test. In this part, the reading acuity measured with the DDVIT and ETDRS test are compared.

All the comparisons will take place in two groups: a) a Normal Vision Group (NVG), and b) a Low Vision Group (LVG) in order to estimate the visual acuity in a population with a wide range of vision.

Study Design

Study Type:

Observational [Patient Registry]

Anticipated Enrollment :

300 participants

Observational Model:

Cohort

Time Perspective:

Prospective

Official Title:

Development and Validation of a Web-based Digital Distance Visual Acuity Test

Actual Study Start Date :

Feb 1, 2021

Anticipated Primary Completion Date :

May 31, 2022

Anticipated Study Completion Date :

Jun 30, 2022

Arms and Interventions

Arm	Intervention/Treatment
Study group 70 patients with normal vision (NVG) 30 patients with low vision (LVG) These patients will be tested on the DDVIT	Diagnostic Test: DDVIT testing One randomly selected eye will be included for each study participant. Participants respond to the DDVIT test in standard environmental lighting conditions at 4 m viewing distance. Visual acuity will be evaluated. Diagnostic Test: ETDRS testing The same eye is included for each study participant. Participants respond to the standard ETDRS chart of our Ophthalmology Department in standard environmental lighting conditions at 4 m viewing distance. Visual acuity will be evaluated.

Arm

Intervention/Treatment

Study group

70 patients with normal vision (NVG) 30 patients with low vision (LVG) These patients will be tested on the DDVIT

Diagnostic Test: DDVIT testing

One randomly selected eye will be included for each study participant. Participants respond to the DDVIT test in standard environmental lighting conditions at 4 m viewing distance. Visual acuity will be evaluated.

Diagnostic Test: ETDRS testing

The same eye is included for each study participant. Participants respond to the standard ETDRS chart of our Ophthalmology Department in standard environmental lighting conditions at 4 m viewing distance. Visual acuity will be evaluated.

Outcome Measures

Primary Outcome Measures

Distance visual acuity using DDVIT vision test [4 months]
The distance visual acuity of the one randomly selected eye of each participant will be evaluated by the examiner using DDVIT vision test.
Distance visual acuity using ETDRS vision test [4 months]
The distance visual acuity of the same eye of each participant will be evaluated by the same examiner using the web-based ETDRS vision test under the same predetermined environmental lighting conditions.

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 75 Years

Sexes Eligible for Study:

All

Inclusion Criteria:

Patients of our outpatient ophthalmology clinic
Age between 18 to 75 years

Exclusion Criteria:

Dyslexia
Attention-deficiency
Former diagnosis of mental and/or psychiatric diseases
Inability to cooperate

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Department of Ophthalmology, University Hospital of Alexandroupolis	Alexandroupolis	Evros	Greece	68100
2	Department of Computer Science and Biomedical Informatics, University of Thessaly	Lamía	Thessaly	Greece	35100