Comparison of SITA-Standard Compared to SITA-Fast Visual Fields.

Study Overview
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Brief Summary
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This study will compare SITA-Standard and SITA-Fast tests in patients newly referred to the glaucoma screening clinic at the RD&E hospital.

Detailed Description
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This study will compare SITA-Standard and SITA-Fast tests in patients newly referred to the glaucoma screening clinic at the RD&E hospital. In addition to standard care (SITA-Fast) each person who agrees to take part in the trial will undertake one extra visual field test (SITA-Standard). By comparing the results of the two types of visual field test the investigators aim to provide information on which of the two tests is more specific for glaucoma and which test is better tolerated by patients. The investigators anticipate that this study will generate sufficient data to support a grant application for a longitudinal study to examine the relative merits of different visual field tests in patients with glaucoma and those suspected of developing the disease.

Official Title
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Specificity and Patient Perception of SITA-Standard Compared to SITA-Fast Visual Fields in Patients Suspected of Having Glaucoma

Conditions
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Glaucoma

Intervention / Treatment
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* Diagnostic Test: SITA FAST VISUAL FIELD TEST
* Diagnostic Test: SITA STANDARD VISUAL FIELD TEST


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients over 18 years old attending the West of England Eye Unit Glaucoma Service who have been newly referred for suspected glaucoma. Exclusion Criteria: 1. Patients who are unable to perform visual field tests. 2. Patients who are unable to have a full glaucoma assessment. 3. Patients who have undertaken visual field tests in hospital eye departments in the last 2 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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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Randomised crossover trial of diagnostic test with assessment of comparative accuracy - feasibility study.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: SITA FAST then SITA STANDARD<br>SITA FAST and SITA STANDARD | Diagnostic Test: SITA FAST VISUAL FIELD TEST<br>* Diagnostic test for glaucoma<br>Diagnostic Test: SITA STANDARD VISUAL FIELD TEST<br>* Diagnostic test for glaucoma<br>|
| Active Comparator: SITA STANDARD then SITA FAST<br>SITA FAST and SITA STANDARD | Diagnostic Test: SITA FAST VISUAL FIELD TEST<br>* Diagnostic test for glaucoma<br>Diagnostic Test: SITA STANDARD VISUAL FIELD TEST<br>* Diagnostic test for glaucoma<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| specificity of the visual field tests | specificity | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patients' rating of test difficulty | number | 1 year | 
| The number of questions asked (number of presented stimuli). | number | 1 year |