Demonstrating Feasibility of Color Vision Deficient Provider Use of EnChroma Products in the Emergency Department
Phase: NA
Conditions: Color Vision Defects
Sponsor: Emory University

Demonstrating Feasibility of Color Vision Deficient 
Provider Use of EnChroma Products in the Emergency 
Department  
(Short title: EnChroma in the ED) 
 
NCT Number: NCT04021914 
 
Protocol Version 6 Date: April 15, 2020 
 

Emory IRB Biomedical Protocol
1. Title Page
Demonstrating Feasibility of Color Vision Deficient Provider Use of EnChroma Products in the Emergency 
Department
Short study title: EnChroma in the ED
Principal Investigator:
Department of Emergency Medicine
Emory University School of Medicine
Sponsor: EnChroma, Berkeley, California
Protocol version: 6
Date: 4/15/2020
2.  External Collaborators: None

3.  Abstract
Color vision deficiency is common among males and can impact medical care in a number of 
ways, including limiting a provider’s ability to note certain physical signs, interpret stool guaiac or urine 
dipstick tests, and to identify colors under a microscope.  While this deficiency does not preclude a 
career in medicine, many such providers will develop “work-arounds” such as involving colleagues with 
normal color vision to care for their patients.  This study seeks to understand whether products made by 
EnChroma to improve color vision will have a positive impact on patient care.  Color vision deficient 
(CVD) providers in the emergency department will be identified using a screening test and then formal 
vision testing.  These CVD providers will receive EnChroma products to utilize during patient care and 
will be surveyed on their experience. 
4.  Introduction and Background
Color discrimination is important in many careers but is particularly important in medical fields 
where decisions may be based on the ability to rapidly detect deviations in blood color, pallor or other 
important clinical signs. Color vision deficiency is the inability to distinguish certain shades of color and 
can range in severity from mild to severe. The most common form is red-green (representing both 
deutan and protan defects) which has an X-linked recessive inheritance pattern,1 thus affecting mostly 
males. Red-green color vision deficiency affects approximately 1 in 12 men and 1 in 200 women in the 
world.2 There are other more rare and more severe forms such as blue-yellow defects (also called tritan 
defects) and blue cone monochromacy which results in poor visual acuity and extremely reduced color 
vision.  As red-green CVD is by far the most common form, research has primarily focused on subjects 
with this form. 
Prior work has demonstrated that medical students and physicians are affected by CVD.  This 
has a number of effects on the practice of medicine by CVD individuals, including: impaired ability to 
recognize abnormalities in stool guaiac tests, blood tests, urine tests,3 histologic stains,4 and 
ophthalmoscope exams,5 as well as impaired ability to detect skin color changes due to cyanosis, 
jaundice or erythema, and rashes.  There have also been case reports of providers with CVD failing to 
identify rectal bleeding resulting in a delay in treatment.6 However, anecdotal reports demonstrate 
multiple “work-arounds” that CVD providers employ to minimize direct effects on patient care.7  The 
vast majority of “work-arounds” reported involve peer corroboration in areas where color 
differentiation is important.5  There is a lack of evidence regarding the effect of provider CVD on patient 
outcomes. 
In addition to impacting patient care, CVD can also impact medical students’ education by 
increasing difficulty with pathology and slide identification as well as anatomy as it impairs one’s ability 
to distinguish certain tissues during dissections.  Prior studies have also demonstrated that CVD impairs 
medical students’ ability to detect color differences in the fundus during retinal exams.  Standardized 
exams during medical school also include color identification on histological stains on pathology slides. 
These difficulties as well as others have led some students to avoid certain medical specialties.8  In 

addition to improving patient care, it may also be possible to reduce disparities in medical school 
performance and choice of specialty caused by CVD. 
EnChroma (Berkeley, CA) has developed multiple products which improve brightness and color 
purity of primary colors for CVD people.  While the manufacturer has reported the effectiveness of 
these products in aiding color vision, they have not yet been shown to cure color vision deficiency, and 
there is individual variation in the response to the glasses given varying degrees of severity and type of 
CVD.9  However, they have not been evaluated yet in a clinical setting to assess their impact on patient 
care by CVD healthcare providers.  Even an incremental increase in a physician’s ability to detect a 
subtle difference may improve that provider’s ability to identify a critical examination finding. Thus, the 
long term goal of the present study is to improve patient care by mitigating the deleterious effects of 
CVD in a clinical setting.  
5.  Study Aims and Outcomes: 
Aim: Evaluate the feasibility of using EnChroma glasses in a patient care environment, as well as 
subjective reflections on the effects of the product on patient care.  CVD providers will wear the 
glasses for 2 weeks. Providers and patients will be surveyed on the comfort of the product, any 
subjective influence on color vision overall, specific examples of improvements or hindrances to patient 
care, and overall impression providing evidence for safety and effectiveness of the product in the 
patient care setting. 
Hypothesis: CVD providers will consider EnChroma products to be unobstructive to their daily work and 
without adverse effect on patient care.
6.   Study Design and Methods
Study Population:
Study participants will be solicited by emails sent to faculty, residents, nurse practitioners, 
physician assistants, and registered nurses in Emory and CHOA’s Department of Emergency Medicine.  
Providers from other departments providing care in the emergency department may also be recruited. 
Students at Emory and Morehouse  will be recruited using electronic and paper flyers posted at 
pre-approved locations on campus as well as through email to the emergency medicine interest groups 
at both schools.  
In addition, members of the medical community outside of Emory will be recruited via the 
EnChroma website.  A link reading “Emory University Seeks Color Blind ER Health Care Providers for 
Research Study, READ ON” will be on the main company website taking users to a page with the 
language in the attached document (Recruitment Language – EnChroma). 
Volunteer subjects will first participate in the online screening test.  Subjects who test positive 
for CVD or who know themselves to have a prior diagnosis of CVD will then undergo confirmatory color 
vision testing with the Farnsworth D15 test and HRR, both with and without EnChroma glasses.  This will 
be performed by study personnel using personal equipment, not during or within Emory Clinic 

resources.  Visual acuity will also be obtained in addition to subject self-report of their ophthalmologic 
and medical history.  They may also supply previously obtained refraction prescription for use in making 
their EnChroma glasses.  
We will not be entering subjects’ medical records to obtain health information at any time.
We do not expect to recruit tritan deficiencies, both because they are rare and because the 
glasses are not expected to be of benefit to this population.  Of note, we expect a gender disparity in 
this study because CVD disproportionately affects males, though we will enroll both CVD males and 
females.  
Study Participant Risk
The devices proposed for testing from EnChroma meet the FDA criteria for non-significant risk 
devices.  The glasses pose no serious risk to the health, safety, or welfare of a subject, and they are not 
of substantial importance in diagnosing or treating disease. Healthcare providers are free to remove or 
discontinue use of these devices while performing patient care if they are hindering patient care in any 
way, reverting to their usual care.  Furthermore, the glasses are currently available to the public without 
prescription and providers are able to purchase and wear them during patient care without approval.  As 
such, we do not anticipate any substantive risk to patients while these are worn during patient care.  We 
will encourage participants to remove the glasses if they feel their medical care is being hindered in any 
way.  Of note, the indoor Enchroma glasses do diminish total light transmission somewhat (50% visible 
light transmission) and a key question in this study is whether that has a significant effect on providers’ 
comfort and ability to deliver care without removing the glasses. 
There is a risk of breach of confidentiality, albeit low.  No personal identifying information will 
be collected about the patients examined as part of this study.  Data will be aggregated before analysis. 
Records of any ophthalmologic examinations performed on entry into the study will be 
maintained by study staff and destroyed at the end of data analysis.  Any new pathologic conditions 
discovered during that examination will be reported to the subjects so that they may seek medical care 
as needed. 
Consent:
CVD subjects will sign informed consent at the time of optometrist evaluation.  They may 
discontinue participation in the study at any time.  
METHODS
Each participant with CVD (other than medical students) will be provided EnChroma products to 
use indoors over the course of two weeks in the emergency department, educational settings, and in 
their personal life.  They will be encouraged to wear the glasses for at least 10 hours over 1-2 weeks 
prior to wearing them in a clinical setting to adjust to their use, and for 10 minutes before beginning 
patient care as per manufacturer instructions.  They will be encouraged to take specific note of clinical 
scenarios that require the use of color vision (e.g., - rashes, tympanic membrane erythema, stool guaiac 

testing, etc.).  Placebo glasses will not be provided given that subjects will not be able to be blinded to 
the difference, and subjects are unlikely to tolerate red tinted glasses which do not provide benefit.  The 
participant will then complete a survey regarding their baseline experience of having CVD, and the 
participant’s reflections on how CVD has affected his/her clinical practice and education in the past, 
including any “work-arounds” they have employed previously.   The survey will also ask them to reflect 
on the impact of the glasses on patient care as well as a 100mm scale in addition to open ended 
questions. 
                Data will be analyzed both quantitatively (improvement on 100mm visual analog scale and any 
change in patient survey responses) as well as qualitatively, using thematic analysis of open ended 
survey data within the grounded theory paradigm.  
In the event of substantial missing data, data will be imputed using a multiple imputation 
procedure. The type of procedure and the number of imputed data sets will be determined by the 
amount of missing data and the pattern of missingness.  However, we do not expect significant missing 
data in this study.  No data will be sent to the FDA.
7.  Participant Selection
-
Sample Size Calculation. Given the number of male providers in Emory’s department of 
Emergency Medicine, and the prevalence of CVD in the general populations, the maximum 
achievable sample size is expected to be approximately 50 participants. A sample size of 50 will 
provide sufficient power (80%) to detect a within-group standardized difference (Cohen’s d) of 
0.44 between the glasses-on and glasses-off conditions.
-
Inclusion/Exclusion Criteria
Inclusion Criteria:

Age 18-65

Red-Green color vision deficiency
Exclusion Criteria

Age>65

Chronic eye conditions limiting color vision including:
o
Achromatopsia
o
Cataracts
o
Glaucoma
o
Legal Blindness
o
Macular Degeneration
o
Retinitis Pigmentosa
-
Subject Recruitment Plan
o
Faculty, Residents, and Nurses in the Department of Emergency Medicine will be 
recruited using email to listserves as well as announcements at department and faculty 
meetings.  
o
Students will be recruited through flyers posted on campus and through emails to the 
EM Interest Group. 

o
CVD subjects will receive EnChroma products to use for the duration of the study and 
may keep them at the end.  EnChroma will be providing all products necessary for the 
purposes of the study. 
-
Screening for eligibility
o
Screening will be self-guided by subjects taking an online color vision test at home on 
the internet (publicly accessible site).  They will share those results with the study 
investigators prior to enrollment.  
-
Subject withdrawal
o
Subjects who choose to withdraw will be permitted to keep any EnChroma products 
which have been provided to them.  
8.  Informed Consent Process
The optometrist co-I will obtain written informed consent at the time of optometrist evaluation.  
Given that all subjects will be local healthcare providers, we expect all will be proficient in English and 
able to consent for themselves.  
We recognize that residents can be considered vulnerable groups in this study.  All participation 
will be voluntary and consent will be obtained by the co-I from Ophthalmology instead of the PI (who is 
faculty in the School of Medicine, and an Associate Residency Program Director).  Permission has already 
been requested and granted to recruit medical students at Emory from Dr. 
, Associate 
Dean for Medical Education and Dr. 
, Assistant Dean for Medical Education Research.  
Permission to recruit Morehouse students is pending from that school, awaiting Emory IRB approval of 
Morehouse as a research site.
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Dadlani NI. Exploring practitioner colour blindness in everyday practice. In: Med J Aust. Vol 197. 
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Spalding JA, Cole BL, Mir FA. Advice for medical students and practitioners with colour vision 
deficiency: a website resource. Clinical & experimental optometry. 2010;93(1):39-41.

9.
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