The Performance of Red Tinted Contact Lenses of Various Tones on Colour Deficient Subjects: A Pilot Study
Phase: NA
Conditions: Color Vision Defects, Color Blindness
Sponsor: National University of Malaysia

Title: The Performance of Red Tinted Contact Lenses of Various Tones on Colour Deficient               
Subjects 
Date: 1/12/2022 
 
 

INFORMATION SHEET 
 
Research Title:  
 
Suitability of Red Tint Lens on Colour Deficient Subjects: A Pilot Study 
 
Introduction:  
 
You are invited to participate in a research study. Before participating in this study, it is 
important that you take time to read and understand the information in this Information Sheet. 
 
Purpose of Study: 
Colour vision deficiency is common disorder that happens when any type of cone 
photoreceptor (L-cone, M-cone or S-cone) is defective or missing, leading to limitation in 
colour discrimination. This condition makes life of colour deficient subject more challenging, 
especially in differentiating traffic light signals, identify ripeness of fruits, discriminating 
colour coding which is designed for safety purposes, limitation in career selection, etc. To date, 
there is no treatment to cure colour vision deficient problem. Many researchers use red filter to 
enhance colour perception. However, there is no guideline in fitting the suitable tone of red 
filter for different types of colour vision deficiency. They manage colour vision deficient 
subject by using “try and error” method without any effective fitting guide. Therefore, this 
study aims to identify the most suitable red tint contact lens for colour vision deficient subjects 
by determining the correlation between wavelength of red tint lens and the total error score 
(TES) value of colour vision deficient subjects from Farnsworth-Munsell 100 Hue test. 
 
What will the study involve? 
This study involves four red tint contact lens from different companies. The wavelength of the 
red tint lens will be measured using a spectrophotometer. Colour vision deficient subjects will 
go through Farnsworth-Munsell 100 Hue test to identify the type of colour vision deficiency 
and TES value. Next, the subjects will undergo Ishihara test with habitual vision. Then, the red 
tint lens will be worn on the non-dominant eye. An adaptation period of 15 minutes will be 
given. Ishihara test will be tested binocularly again. This procedure will be repeated by using 
the four red tint lenses. The amount of pass and fail plates will be recorded. After all the 
measurements have been taken, subjects will be discharged.  
 
Risks and Benefits:   

The colour vision deficient subjects could identify the most suitable red tint lens which helps 
in enhancing colour perception after participating in this study. Risk of each procedure will be 
unlikely as procedures that are chosen are minimally invasive and there will be no drug or 
topical drops involved in this study.  
 
Do you have to take part? 
Participation in this study is voluntary. If you agree to take part, then you will be asked to sign 
the “Informed Consent Form”. You will be given a copy of the form and this Information Sheet. 
Should you decide to participate, you can still withdraw from the study without penalty. 
However your data will be retained by us. The researcher may also remove you from the study 
for a variety of reasons. In this event, you will not be penalized or lose your rights as a patient.  
 
Data & Confidentiality: 
The data from this study will be made into a report which may be published.  Access to the 
data is only by the research team and the REC UKM. The data will be reported in a collective 
manner with no reference to an individual. Hence your identity will be kept private and 
confidential. 
 
Payment and compensation: 
You do not have to pay nor will you be paid to participate in this study. There will be no 
compensation or travel allowance given as the participant of this study. However, during the 
15 minutes time interval, light snacks will be provided by the research team.  
 
Who can I ask about the study? 
If you have any questions, you can direct them to the research team.  
 
Research Team 
 
Main Researcher: Associated Prof. Dr. Haliza Abdul Mutalib 
Student Researcher: Ong Yi Lin (A162789) 
Faculty of Health Sciences (UKM), Optometry Clinic 
Phone Number: 016-5157485 / 013-7877011 
Hotline: 03-9289-7499 (UKM Clinic) 

Appendix C. Informed Consent Form 
 
INFORMED CONSENT FORM 
 
Research Title: Suitability of Red Tint Contact Lens on Colour Vision Deficient Subject: A 
Pilot Study.  
Researcher’s Name: Ong Yi Lin 
I, ………………………………………………………………IC No :  …………………......  
• have read the information in the Patient Information Sheet including information 
regarding the risk in this study  
• have been given time to think about it and all of my questions have been answered to 
my satisfaction. 
• understand that I may freely choose to withdraw from this study at anytime without 
reason and without repercussion 
• understand that my anonymity will be ensured in the write-up. 
I voluntarily agree to be part of this research study, to follow the study procedures, and to 
provide necessary information to the doctor, nurses, or other staff members, as requested. 
 
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      (Date) 
 
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Witness (if any) 
 
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(Signature)           
 
………………………………. 
(IC Number) 
 
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(Date)                               
 
 
………………………………. 
Researcher 
 
………………………………. 
(Signature)           
 
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(IC Number) 
 
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(Date)