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Trial registered on ANZCTR


Registration number
ACTRN12616001526460
Ethics application status
Approved
Date submitted
2/11/2016
Date registered
7/11/2016
Date last updated
1/03/2017
Type of registration
Prospectively registered

Titles & IDs
Public title
Investigation of vision and subjective changes when altering
cylindrical power and axis in healthy adults with normal vision
Scientific title
Investigation of vision and subjective changes when altering
cylindrical power and axis in healthy adults with normal vision
Secondary ID [1] 290454 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Astigmatism 300818 0
Condition category
Condition code
Eye 300642 300642 0 0
Normal eye development and function

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Participants will attend a baseline visit at the Brien Holden Vision Institute, where a qualified optometrist will measure their best-corrected subjective refraction (required sphere power and required cylinder power) using a phoropter.

Following the baseline, participants will attend 4 separate visits on different days at the Brien Holden Vision Institute. Each visit will take approximately 30 minutes.

At each of these visits, participants will undergo pre-determined changes to their cylindrical axis and power in a randomised fashion using a phoropter, by a qualified optometrist. Visual acuity (taken with an electronic letter chart at 6 metres) and subjective vision response (clarity, vision satisfaction using a 1-10 numeric scale) will be obtained for each change.

A different cylinder power is assessed at each visit: (1) the required cylinder power, (2) the required cylinder power minus 0.25 D, (3) the required cylinder power minus 0.50 D or (4) the required cylinder power minus 0.75 D. The order of these powers is randomised.

Within each visit, the following cylindrical axes will be tested in a randomised fashion: aligned, misaligned by +10 degrees, +20 degrees, +30 degrees, -10 degrees, -20 degrees, -30 degrees.

In summary, at each of the four visits, participants will be shown 7 different views of a letter chart, and vison and subjective response will be measured for each view.

The washout period between each cylindrical axis will be approximately 5 minutes. The washout period between each cylindrical power will be at least one night.
Intervention code [1] 296303 0
Treatment: Other
Comparator / control treatment
The comparator is when the participant's cylindrical power is the required cylinder power, and when the cylindrical axis is aligned.
Control group
Active

Outcomes
Primary outcome [1] 300049 0
Change in visual acuity using an electronic letter chart at 6 metres
Timepoint [1] 300049 0
Within 5 minutes of changing the cylinder axis
Secondary outcome [1] 328920 0
Change in subjective vision clarity using a 1-10 numeric scale
Timepoint [1] 328920 0
Within 5 minutes of changing the cylinder axis
Secondary outcome [2] 328943 0
Change in subjective vision satisfaction using a 1-10 numeric scale
Timepoint [2] 328943 0
Within 5 minutes of changing the cylinder axis

Eligibility
Key inclusion criteria
-Able to read and comprehend English and give informed consent as
demonstrated by signing a record of informed consent.
-Be at least 18 years old, male or female.
-Have at least 0.75D cylindrical power in at least one eye.
-Willing to comply with the clinical trial visit schedule as directed by the
Investigator.
-Have ocular health findings considered to be “normal” and which
would not prevent the participant from giving accurate visual acuity
data.
Minimum age
18 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
-Any pre-existing ocular irritation, injury or condition (including
infection or disease) of the cornea, conjunctiva or eyelids that would
affect visual acuity measurements.
-Any systemic disease that adversely affects ocular health e.g.
diabetes, Graves disease, and auto-immune diseases such as
ankylosing spondylitis, multiple sclerosis, Sjogrens syndrome and
systemic lupus erythematosus. Conditions such as systemic
hypertension and arthritis do not automatically exclude prospective
participants.
-Use of or a need for concurrent category S3 and above ocular
medication at enrolment and/or during the clinical trial.
-Use of or a need for any systemic medication or topical medications
which may alter normal ocular findings / are known to affect a
participant’s ocular health / physiology or visual acuity either in an
adverse or beneficial manner at enrolment and/or during the clinical
trial.
-Eye surgery within 12 weeks immediately prior to enrolment for this
trial.
-Rigid gas permeable (RGP) or Orthokeratology lens wear within
previous 12 months
-Previous corneal refractive surgery.
-Currently enrolled in another clinical trial.
-Pregnancy.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation not concealed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The randomisation will be generated from http://www.randomization.com. A randomisation list will be generated by the biostatistician and applied through the Clinic Data Management system.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s


Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
Visual acuity will be recorded on a LogMAR scale. Data will be summarised as means +/- standard deviations. No transformation is likely to be required. Visual acuity will be compared between cylindrical powers and axis using repeated measures ANOVA and/or linear mixed model. Interactions will be tested and, if present, the significance of a factor will be determined for each level of the other factor.

Subjective ratings will be recorded on a scale of 1 to 10 on steps of 1. Data will be summarised as means +/- standard deviations. No transformation is likely to be required. Subjective ratings will be compared between cylindrical powers and axis using repeated measures ANOVA and/or linear mixed model. Interactions will be tested and, if present, the significance of a factor will be determined for each level of the other factor.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
NSW

Funding & Sponsors
Funding source category [1] 294864 0
Commercial sector/Industry
Name [1] 294864 0
Brien Holden Vision Institute
Address [1] 294864 0
Level 5 North Wing, Rupert Myers Building, Gate 14 Barker Street, UNSW 2052
Country [1] 294864 0
Australia
Primary sponsor type
Commercial sector/Industry
Name
Brien Holden Vision Institute
Address
Level 5 North Wing, Rupert Myers Building, Gate 14 Barker Street, UNSW 2052
Country
Australia
Secondary sponsor category [1] 293704 0
None
Name [1] 293704 0
Address [1] 293704 0
Country [1] 293704 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 296247 0
Bellberry Human Research Ethics Committee
Ethics committee address [1] 296247 0
129 Glen Osmond Rd, Eastwood SA 5063
Ethics committee country [1] 296247 0
Australia
Date submitted for ethics approval [1] 296247 0
14/09/2016
Approval date [1] 296247 0
28/10/2016
Ethics approval number [1] 296247 0
2016-09-692

Summary
Brief summary
This study aims to find out how varying eye prescription impacts on vision and satisfaction of vision. To achieve this, we wish to monitor participants' eyes’ responses to the changes to their prescription we introduce. A minimum of 20 people will take part in this study.
At each visit, a pre-determined number of changes to their prescription will be shown to the participant through a phoropter (standard optometric equipment used to determine spectacle prescriptions), they will then be asked to read a letter chart and rate their vision clarity and satisfaction.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 70130 0
Ms Jennifer Sha
Address 70130 0
Brien Holden Vision Institute
Level 5, North Wing,
Rupert Myers Building
Gate 14, Barker Street
UNSW Sydney NSW 2052
Country 70130 0
Australia
Phone 70130 0
+61293859811
Fax 70130 0
Email 70130 0
j.sha@brienholdenvision.org
Contact person for public queries
Name 70131 0
Miss Kassandra Wagenfuehr
Address 70131 0
Brien Holden Vision Institute
Level 5, North Wing,
Rupert Myers Building
Gate 14, Barker Street
UNSW Sydney NSW 2052
Country 70131 0
Australia
Phone 70131 0
+61293855934
Fax 70131 0
Email 70131 0
k.wagenfuehr@brienholdenvision.org
Contact person for scientific queries
Name 70132 0
Dr Ravi Bakaraju
Address 70132 0
Brien Holden Vision Institute
Level 5, North Wing,
Rupert Myers Building
Gate 14, Barker Street
UNSW Sydney NSW 2052
Country 70132 0
Australia
Phone 70132 0
+61293857455
Fax 70132 0
Email 70132 0
r.bakaraju@brienholdenvision.org

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary