Contrast sensitivity measurement validation testing program
| ISRCTN | ISRCTN15565274 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN15565274 |
| IRAS number | 359150 |
- Submission date
- 29/07/2025
- Registration date
- 29/07/2025
- Last edited
- 29/07/2025
- Recruitment status
- Recruiting
- Overall study status
- Ongoing
- Condition category
- Eye Diseases
Plain English summary of protocol
Background and study aims
Presbyopia is the gradual loss of the eye's ability to focus on nearby objects due to natural aging.
Visual performance measurement is traditionally based upon visual acuity measurement and occasionally on the measurement of contrast sensitivity. The latter method, considered to be more sensitive at detecting differences in performance between different optical designs than visual acuity, uses linear or circular sinusoidal contrast target.
The study aim is to determine the sensitivity of two contrast sensitivity tests in detecting changes in contrast sensitivity associated with refractive defocus.
Who can participate?
Presbyopes aged between 40 to 50 years old.
What does the study involve?
Part 1 involves attending the clinic for nine study visits.
Part 2 involves attending the clinic for five study visits
What are the possible benefits and risks?
The study results will contribute to collect additional information about visual performance variability under different contrast conditions.
Where is the study running from?
Ocular Technology Group - International (OTG-i) (UK)
When is the study starting and how long is it expected to run for?
July 2025 to October 2025
Who is funding the study?
Alcon Research, LLC (Switzerland)
Who is the main contact?
Deborah Moore, dmoore@otg.co.uk
Contact information
Public
66 Buckingham Gate
London
SW1E 6AU
United Kingdom
| Phone | +44 2072224224 |
|---|---|
| dmoore@otg.co.uk |
Scientific, Principal Investigator
66 Buckingham Gate
London
SW1E 6AU
United Kingdom
| Phone | +44 2072224224 |
|---|---|
| mguillon@otg.co.uk |
Study information
| Study design | Part 1: Exploratory part following a clinic based prospective randomized cross-over study design Part 2: Clinic based prospective single group study design |
|---|---|
| Primary study design | Interventional |
| Secondary study design | Part 1: Prospective randomized cross over; Part 2: Prospective single group |
| Study setting(s) | Other |
| Study type | Efficacy |
| Participant information sheet | Not available in web format, please use contact details to request a participant information sheet |
| Scientific title | Contrast sensitivity measurement validation testing program - phase 1 - test resolution determination |
| Study objectives | Part 1: determination of the sensitivity of the test in detecting change in contrast sensitivity associated with refractive defocus. Part 2: determination of the test ability to measure binocular summation via the measurement of contrast sensitivity through focus curve. |
| Ethics approval(s) |
Approved 10/07/2025, North of Scotland Research Ethics Committee (Summerfield House, 2 Eday Road, Aberdeen, AB15 6RE, United Kingdom; +44 1224558458; gram.nosres@nhs.scot), ref: 25/NS/0063 |
| Health condition(s) or problem(s) studied | Presbyopia |
| Intervention | Part 1 will be an exploratory part following a clinic based, prospective, randomized cross-over study design testing the sensitivity to defocus of both linear sinusoidal contrast sensitivity and letter contrast sensitivity. Part 1 will involve 9 study visits. The rationale for including sinusoidal contrast sensitivity measurements only in this part is that the repeatability of the technique has been shown to be poorer than the repeatability of letter contrast sensitivity , therefore it is not anticipated that sensitivity to refractive blur will be as good which trend should be demonstrated with only a small study population. The objective of the two part approach is minimizing participants burden due to the large different in the repeatability of the two methods. Part 2 will follow a clinic based, prospective single group study design testing only letter contrast sensitivity. Part 2 will involve 5 visits. |
| Intervention type | Other |
| Primary outcome measure | Measurement of Contrast sensitivity at photopic (85cd/m²) and mesopic (3cd/m²) luminance using timed controlled contrast sensitivity visual acuity with the OTGi vision suite and M&S Technology between four and nine times during the study visit |
| Secondary outcome measures | Measurement of high contrast timed logMAR visual acuity at photopic (85 cd/m²) luminance using timed controlled visual acuity using OTGi vision suite 9 times during the first study visit |
| Overall study start date | 01/05/2025 |
| Completion date | 30/10/2025 |
Eligibility
| Participant type(s) | Healthy volunteer |
|---|---|
| Age group | Adult |
| Lower age limit | 40 Years |
| Upper age limit | 50 Years |
| Sex | Both |
| Target number of participants | Part 1: 10 & Part 2: 25 |
| Key inclusion criteria | 1. Age 40 to 50 years 2. Spectacle refraction: Distance: Sphere: -6.00D to + 2.00D Astigmatism: 0.00D to -0.75D Near Add +0.50 to +2.50D 3. Spectacles or soft contact lenses habitual vision correction 4. Best corrected visual acuity of at least 20/25 in each eye |
| Key exclusion criteria | 1. Any history of eye disease, injury or abnormality that affects any part of the eye that affects vision 2. Any active eye disease that affects any part of the eye that affects vision 3. Corneal hypoesthesia (reduced corneal sensitivity), if not aphakic 4. Newly prescribed (within the past 30 days) use of some systemic medications (such as antihistamines, decongestants, diuretics, muscle relaxants, tranquilizers, stimulants, anti-depressants, anti-psychotics, oral contraceptives) or ocular medication that may affect vision and its stability as determined by the investigator 5. Enrolment of the family members of the investigator, family members of the investigator’s staff, or individuals living in the households of these individuals |
| Date of first enrolment | 17/05/2025 |
| Date of final enrolment | 30/10/2025 |
Locations
Countries of recruitment
- England
- United Kingdom
Study participating centre
London
SW1E 6AU
United Kingdom
Sponsor information
Research organisation
66 Buckingham Gate
London
SW1E 6AU
United Kingdom
| Phone | +44 2072224224 |
|---|---|
| dmoore@otg.co.uk |
Funders
Funder type
Industry
No information available
Results and Publications
| Intention to publish date | |
|---|---|
| Individual participant data (IPD) Intention to share | No |
| IPD sharing plan summary | Not expected to be made available |
| Publication and dissemination plan | There are no plans at this stage for publication or dissemination. |
| IPD sharing plan | Not expected to be made available |
Editorial Notes
29/07/2025: Trial's existence confirmed by NHS Grampian.
