Try our beta test site
IMPORTANT: Listing of a study on this site does not reflect endorsement by the National Institutes of Health. Talk with a trusted healthcare professional before volunteering for a study. Read more...
Trial record 1 of 5 for:    Open Studies | "Color Vision Defects"
Previous Study | Return to List | Next Study

Evaluating Color Perception Under LED Red/Green and Green Dominant Light

This study is currently recruiting participants. (see Contacts and Locations)
Verified October 2016 by University of Colorado, Denver
Information provided by (Responsible Party):
University of Colorado, Denver Identifier:
First received: August 2, 2013
Last updated: October 19, 2016
Last verified: October 2016
The investigators are testing a Light-emiting Diode (LED) flashlight from First-Light™ USA called the Tomahawk MC Tactical Light to determine the range of colors people are able to see with these flashlights at night. The flashlight has been designed to reduce visibility of the user and uses a combination of green and red LED lamps to achieve this. In this study investigators wish to determine how well a subject can differentiate colors at night in a quantifiable manner. Investigators will use the Farnsworth Munsell 100 hue test which requires the user to put shades of red, green, blue and yellow into progressive color order which is scored according to the manufactures specifications.

Condition Intervention
Color Blindness, Acquired
Device: White LED Flashlight
Device: Red/Green Green Dominant LED Flashlight

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Evaluating Color Perception Under LED Red/Green and Green Dominant Light

Resource links provided by NLM:

Further study details as provided by University of Colorado, Denver:

Primary Outcome Measures:
  • Change in Normal Color vision [ Time Frame: 1 hr ]
    The Farnsworth Munsell 100 Hue Test is used to determine normal color vision and vision using the red green Tomahawk LED flashlight.

Estimated Enrollment: 200
Study Start Date: July 2013
Estimated Study Completion Date: April 2017
Estimated Primary Completion Date: April 2017 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
Night Vision
White LED Flashlight, Red/Green Green Dominant LED Flashlight
Device: White LED Flashlight
white light setting
Other Name: Tomahawk serial number TMC12420
Device: Red/Green Green Dominant LED Flashlight
Green LED light dominant setting
Other Name: Tomahawk serial number TMC12420, green dominant setting


Ages Eligible for Study:   18 Years to 66 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
Normal color vision status

Inclusion Criteria:

  • normal vision
  • 18-65 years

Exclusion Criteria:

  • blindness
  • colorblind
  • pregnant women
  • prisoners
  • decisionally challenged
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01927536

Contact: Mark Petrash, PhD 303/724-0681

United States, Colorado
University of Colorado Dept of Opthalmology Recruiting
Aurora, Colorado, United States, 80045
Contact: Michelle G Pedler, BSc Hons    303-724-3013   
Contact: Mark Petrash, PhD    303 724 0681   
Principal Investigator: Mark Petrash, PhD         
Sponsors and Collaborators
University of Colorado, Denver
Principal Investigator: Mark Petrash, PhD University of Colorado, Denver
  More Information

Responsible Party: University of Colorado, Denver Identifier: NCT01927536     History of Changes
Other Study ID Numbers: 13-0387
Study First Received: August 2, 2013
Last Updated: October 19, 2016

Additional relevant MeSH terms:
Color Vision Defects
Vision Disorders
Sensation Disorders
Neurologic Manifestations
Nervous System Diseases
Eye Diseases
Signs and Symptoms processed this record on May 24, 2017