Plain English Summary
Background and study aims
The shape of the edge of the contact lens influences the way the lens fits on the eye and its comfort. Different contact lenses have got different edges. The aim of the study is to compare how the lens fits on the eye along with its comfort for different multifocal contact lenses with different edge designs.
Who can participate?
Adults who are least 40 years old, who have healthy eyes, who wear contact lenses and are starting to get longsightedness (near addition +0.75 to +1.25).
What does the study involve?
A single visit during which the participant will use the 3 study contact lenses each for 2 hours.
What are the possible benefits and risks of participating?
The participants are current contact lens wearers and they will use under the control of the investigator the 3 currently marketed contact lenses. The risks to the participant are no greater than wearing their own contact lenses. The risks will be further minimised by the fact that the contact lenses will only be worn in the clinic under the supervision of the investigators. The possible benefit to the participant will be to try different contact lenses with different levels of comfort that they could eventually purchase from their own practitioner.
Where is the study run from?
Ocular Technology Group International (UK)
When is the study starting and how long is it expected to run for?
May 2020 to December 2020
Who is funding the study?
Cooper Vision Inc (USA)
Whi is the main contact?
Mrs Deborah Moore
66 Buckingham Gate
+44 (0)207 222 4224
CV20-42 ID20-17, IRAS 281961
The effect of contact lens parameters and material on fitting characteristics - pilot study
Mechanical performance of contact lenses with a feather edge design is not inferior to that with a chisel edge design.
Approved 04/05/2020, North West - Preston Research Ethics Committee (Barlow House, 3rd Floor, 4 Minshull Street, Manchester, M1 3DZ, UK; +44 (0)207 104 8056; email@example.com), ref: 20/NW/020
Non dispensing prospective randomised (order of testing) cross over double-masked study
Primary study design
Secondary study design
Randomised cross over trial
Patient information sheet
Not available in web format, please use contact details to request a participant information sheet
Presbyopia multifocal contact lens fitting
Each participant uses all 3 contact lenses in a random order for a 2 hour period, after which the contact lens fitting measurement and comfort measurement are being carried out.
1. Measurement of contact lens decantation (horizontal and vertical) from the centre of the pull (mm). The measurement to be performed in primary gaze and reading gaze.
2. Lens centration and lens movement classification on 5 point scale.
3. Contact lens comfort rating on 100 point VAS scale.
Clariti 1 day single vision contact lens
Clariti 1 day multifocal low addition contact lens
MyDay multifocal low addition contact lens
Primary outcome measure
Contact lens decentration is measured from high speed video taken after 2 h of wear
Secondary outcome measures
Measured after 2 h of wear:
1. Lens centration rating on a 5 point scale by investigator using a slit lamp biomicroscope
2. Lens movement rating on a 5 point scale by investigator using a slit lamp biomicroscope
2. Comfort rating by participant using a computer based 100 point VAS scale
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
1. At least 40 years old
2. Have read and understood the Participant Information Sheet in English
3. Have read, signed and dated the Informed Consent
4. Best corrected visual acuity of at least 20/25 in each eye
5. Have normal eyes with the exception of the need for visual correction
6. Current contact lens wearer
7. Spectacle refraction:
Distance: Sphere: -6.00D to + 4.00D
Astigmatism: 0.00DC to -0.75DC
Near Addition: +0.75D to +1.25D
8. Be willing and able to adhere to the instructions set in the clinical protocol and maintain the appointment schedule
Target number of participants
Participant exclusion criteria
1. Ocular anterior segment infection, inflammation, abnormality, or active disease that would contraindicate contact lens wear
2. 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 new prescription eyedrops which is not rewetting/lubricating eyedrops for which contact lens wear could be contraindicated as determined by the investigator
3. Monocular participants (only one eye with functional vision) or participants fit with only one lens
4. Any moderate or severe ocular condition observed during the slit-lamp examination at the enrolment visit
5. History of herpetic keratitis, ocular surgery or irregular cornea
6. Known pregnancy or lactation during the study period
7. Enrolment of the investigator or his/her staff, family members of the investigator, family members of the investigator’s staff, or individuals living in the households of these individuals
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
Ocular Technology Group - International
66 Buckingham Gate
Cooper Vison Inc. (USA)
6150 Stoneridge Mall Road
United States of America
+1 925 251 6682
Cooper Vision (Inc) USA
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
There are no specific plans for publication or dissemination of the study results. However, an abstract for submission at an ophthalmic conference and/or a peer-reviewed publication may be generated.
IPD sharing statement:
The current data sharing plans for this study are unknown and will be available at a later date.
Intention to publish date
Participant level data
Not provided at time of registration
Basic results (scientific)