EyeOnVision June, 2021 - New Low Contrast Test!
Mayer-Kran™ Double-Happy™ Low Contrast Test
Standardizing Pediatric and Non-Verbal Contrast Sensitivity Assessment
Calibrated schematic face stimulus plates showing fading contrast boundaries
Overcoming Letter Test Limitations
The Mayer-Kran™ Double-Happy™ Low Contrast Test is explicitly intended for children and older individuals who are unable to name or match letters—meaning individuals who cannot be tested with standard, row-based letter contrast tests.
The test cards are printed with a smiling schematic face offset from the exact center of the card area. By design, the face layout remains completely identical when the card is rotated 180°, preserving forcing parameters while avoiding edge cues.
Read More Product SpecsPrecision Vision is humbled and honored to partner with Dr. D. Luisa Mayer, Associate Professor, and Dr. Barry S. Kran, Professor, of the New England College of Optometry. Through this collaboration, we are proud to introduce a brief overview of this design from the developers' perspective:
As clinicians, we realized that young patients had difficulties seeing low-contrast objects, yet there was no reliable, validated test appropriate for their cognitive stage.
2. Why did you take on this work?To provide a quick and useful test of contrast sensitivity (CS) for a diverse pediatric population and older compromised patients as well.
3. What was your development timeline?We started researching this test years ago with students from the New England College of Optometry, our parent institution. Learning from those pilot studies, the test framework transitioned to validation trials with young clinic patients in approximately 2014.
4. Any interesting lessons learned during development?We encountered patients with relatively good acuity scores and grossly full visual fields whose daily functional navigation matched severe visual impairment. Our test revealed they had profoundly degraded contrast processing. Identifying this allowed us to implement tailored compensatory learning strategies to improve daily activities.
Individuals who cannot perform letter contrast matrices like the Pelli-Robson and Mars tests. This covers young children, individuals with significant intellectual disabilities, and older adults who have lost letter literacy.
6. What makes this test unique to the eye care industry?- The highly recognizable, non-verbal schematic face stimulus.
- An architecture and method that matches the Teller Acuity Cards®* framework.
- Dual tracking formats: A Full set (for threshold definition) and a rapid Screening set.
It is a behavioral measure of contrast function rather than a standalone medical diagnosis. Conditions strongly associated with reduced scores include Cerebral Visual Impairment (CVI), various ocular pathologies, and developmental delay.
8. What is your favorite feature of this test?- Objective Administration: The examiner can track looking behavior blindly, without knowing which side features the active face.
- Geometric Calibration: The horizontal dimension of the test card matches the exact physical testing lane distance.
Q: Is there existing research on the Mayer-Kran™ Double-Happy™ Low Contrast Test?
A: Yes, absolutely. Dr. Mayer and Dr. Kran published a dedicated peer-reviewed study establishing the test-retest reliability parameters of this framework across pediatric patient samples. This research provides clinicians with a definitive index of what constitutes a statistically significant change in contrast sensitivity between alternative examiners or subsequent follow-up visits.
Crucially, the results demonstrated that contrast sensitivity in patients diagnosed with Cerebral Visual Impairment (CVI) was significantly reduced compared to patients presenting with purely peripheral ocular disorders, establishing strong differential tracking indicators.
Do you have questions about integrating forced-choice non-verbal looking metrics into your pediatric clinical lane, or do you need calibration coordinates for an active multi-site clinical trial protocol? Connect with our dedicated tracking support station.
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