Color Vision Testing in the Workplace: Pre-placement exams for healthcare workers

Background

Color vision screening for select healthcare workers plays an important role in the promotion of patient and community safety.  Color vision deficiency (CVD) is highly prevalent in the general population, yet a large proportion of CVD individuals are unaware of their condition¹.  CVD individuals aware of their deficiency may still not be aware of the severity of their deficiency or of its potential to affect their work performance. 

To ensure screening effectiveness and avoid potential for discrimination, medical centers should adopt standardized policies and procedures for determining whose essential job functions require color discrimination and protocol for in-office and remote testing.  There is limited utility in screening all applicants whose jobs may involve, but not require, color discrimination. Additionally, such screening increases exposure to potential liability when assessing for non-essential job tasks. Applicants for whom CVD would not pose significant safety concerns nor affect their ability to perform their essential job functions should be excluded from testing.  Accordingly, certain applicants (e.g. providers and nurses, drivers) who have traditionally been required to submit to color vision screening are should not continue to do so.

Regulations

Sound protocols should be developed in accordance with recommendations promulgated by a variety of professional and regulatory bodies.  The College of American Pathologists (CAP) accreditation program requires color vision testing for newly hired laboratory personnel.² Law enforcement agencies, including institutional Police Departments, routinely require color vision screening³, and the American College of Occupational and Environmental Medicine (ACOEM) has recommended screening for Law Enforcement Officers.⁴  Other organizations, such as the Joint Commission and the Food and Drug Administration, do not mandate color vision testing but have issued guidance to healthcare organizations recommending that mechanisms be in place to evaluate those employees whose jobs require color discrimination.^{5, 6} 

Testing

Ishihara plates have been the most widely used color vision screening test for decades, and remain an effective, user-friendly tool for detecting red-green CVD.^{7, 8}  However, Ishihara plate testing does not provide information on the severity of CVD, which in some cases may determine whether an applicant is qualified to perform his or her essential job functions.  The online Farnsworth D-15 Color Blindness test is used both to confirm the presence of CVD and to establish its severity.  Applicants with only mild CVD are frequently able to perform color discrimination tasks without significant safety concerns.  Those with “moderate” or “severe” deficiencies should be referred to an ophthalmologist for additional evaluation⁹.  Applicants with at least moderate CVD should undergo functional testing designed to assess their ability to perform the color vision-related essential job functions required by their position.  Those who fail functional testing should discuss potential work modifications with their hiring manager and/or pursue an accommodation under the Americans With Disabilities Act. 

References:

1. Cole, BL. Assessment of inherited colour vision deficiencies in clinical practice. Clin Exp Optom. 2007;90:(157-175).
2. College of American Pathologists. GEN.55400 Visual Color Discrimination. In: Laboratory General Checklist: CAP Accreditation Program. Northfield, IL; 2021:87-87.
3. North Carolina Criminal Justice Education and Training Standards Commission. Medical Screening Guidelines for the Certification of Criminal Justice Officers in the State of North Carolina. https://mitchellcc.edu/sites/default/files/BLET-Medical-Screening-Guidelines.pdf. Published November 2008.
4. Guidance for the Medical Evaluation of Law Enforcement Officers, provided by ACOEM. https://www.leoguidance.org/. Published 2021.
5. The Joint Commission. Is employee color-blind testing required? https://www.jointcommission.org/standards/standard-faqs/laboratory/waived-testing-wt/000001719/. Published October 26, 2021.
6. Food and Drug Administration. Recommendations for Clinical Laboratory Improvement Amendments of 1988 (CLIA) Waiver Applications for Manufacturers of In Vitro Diagnostic Devices. https://www.fda.gov/media/109582/download. Published February 26, 2020.
7. American Academy of Ophthalmology. How Color Blindness is Tested. https://www.aao.org/eye-health/diseases/how-color-blindness-is-tested/. Published August 25, 2017.
8. Birch J. Efficiency of the Ishihara test for identifying red-green colour deficiency. Ophthalmic Physiol Opt. 1997; 17: 403-8.
9. Melamud A, Hagstrom S, Traboulsi E. Color vision testing. Ophthalmic Genet. 2004;25(3):159-187. doi:10.1080/13816810490498341.