Usability of the Software MacuFix for the Categorization of Metamorphopsia

Study Overview
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Brief Summary
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The usability of a novel test to categorize a distorted visual impression (metamorphopsia) is examined with the questionnaire SUS

Detailed Description
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Introduction Diseases of the retinal centre (macula) can lead to a distorted visual impression (metamorphopsia). The usability of a novel on-screen test to categorize metamorphopsia is to be examined with the questionnaire SUS to determine how user-friendly the software is perceived. Purpose To examine the usability of the software for persons perceiving metamorphopsia employing the questionnaire SUS. Aim of the work Improvement of the software in terms of user-friendliness. Methods For this observational pilot study, 30 persons are to be recruited from the patient pool of a private practice. Primary endpoint: Score of the SUS questionnaire. Each participating person performs the test once with each eye wearing appropriate near correction. The test shows on a screen 4 square fields with a grid pattern of horizontal and vertical lines. All 4 fields have lines that are partially distorted. The task of the test person is to select the field with more distinctively distorted lines when viewed with one eye.This selection must be made at least 10 times per eye: an algorithm determines the smallest correctly named distortion difference. Afterwards each person answers the System Usability Scale (SUS) questionnaire, SUS contains five positive and five negative statements on the usability of the system being evaluated. For each statement, the study participant gives his or her approval or rejection in the form of a scale ranging from 1= strong approval to 5= strong rejection of the statement. The results of the SUS questionnaire are used to calculate a numerical value (SUS score).

Official Title
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Usability of the Software MacuFix for the Categorization of Metamorphopsia and Evaluation of Patient Adherence Compared to the Amsler Grid

Conditions
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Vision Disorders

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Distorted visual impression in at least one eye, detected with Amsler grid: Best-corrected visual acuity (BCVA): at least 20/200; age over 18 years; presence of a declaration of consent to participate in the study Exclusion Criteria: No distorted visual impression in both eyes; best corrected visual acuity under 0.1; age under 18 years

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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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Score of System Usability Scale (SUS) Questionnaire | Patients filled out the SUS questionnaire immediately after completing the MacuFix test. SUS consists of ten statements each with five possible answers ranging from complete rejection to complete agreement. For each statement, the participant gives his or her approval or rejection in the form of a scale ranging from 1=strong approval to 5=strong rejection. The results of the SUS questionnaire are used to calculate a numerical value (SUS score).The results can have a value between 0 (worst application imaginable) and 100 (best application imaginable) | 1 day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Median Time Interval (in Days) Between Two Self-test Measurements (MakuFix or Amsler Respectively) to Assess the Test Adherence | After a positive vote by the Ethics Committee of the North Rhine Medical Association (No. 2020057) 45 patients were included in the study from 4th May, 2020 - 30th June, 2020. Based on the amendment approval of the competent ethics committee (No. 600213225) participating persons were offered to use the App MacuFix® as a home test and to start a prospective, controlled study to examine the adherence using a self-test and evaluate the vison-related quality of life. On the study day and 3 months later each patient was asked about the frequency of use of the Amsler test. The time interval given by the patient between two Amsler Tests (Amsler group) or two MacuFix texts (MacuFix group) was assessed in days. | On the study day and 3 months after the study day, patients were asked how many days usually elapsed after a test with the method they chose until the next time they used this test method. | 
| Change of Vision-related Quality of Life (NEI VFQ-25, Subscale 7) After Use of the App MacuFix Versus Amsler Grid/no Test | The validated questionnaire National Eye Institute Visual Function Questionnaire-25 (NEI VFQ-25) was used to measure vision-related quality of life. The values in the questionnaire can take values from 0 to 100. High values in this questionnaire correspond to a better quality of life, low values to a poor quality of life. The 25 questions of this questionnaire can be assigned to 12 scales. | The validated questionnaire National Eye Institute Visual Function Questionnaire-25 (NEI VFQ-25) was used at baseline and after 3 months. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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metamorphopsia, age-related macular degeneration, diabetic macular edema, home test