5 modern methods for quantifying the eye dominance
Traditional methods classify eye dominance as either left or right. But in clinical settings and sports vision, it's often important to quantify the relative strength of dominance.
To do this, several newer methods have been developed. These include: Guillon’s Pointing test, Domitest-M, Binocular Sighting test, Freiburg Ocular Prevalence test, 2Cameras Ocular Dominance.
All these techniques involve aligning two objects placed at different distances.
Guillon’s pointing test
- The test uses a chart marked with horizontal lines spaced one prism diopter apart. A red cross placed at the center (zero position) serves as the target.
- The person clasps their hands together and, with both eyes open, aligns their index fingers with the target.
- The examiner alternately covers one of the person's eyes and asks which number on the chart they appear to be pointing to.
- Eye dominance score is the sum of the two numbers obtained with right and left eye occluded.
Pros
- Quick and easy to administer
- Allows measurement of eye dominance at different distances
Cons
- Relies on self-report without external verification or objective record, making it vulnerable to subjectivity and consistency bias
- Perceived alignment can shift if the person moves their head during the test
- Difficult to standardize testing condition including posture and hand position.
The method is described in Ho et al. (Clin. Exp. Optom. 2018)
Domitest – M (Tetra platform)
- This is a modern adaptation of the hole-in-the-card method. The card is held halfway between the person and a screen displaying a horizontal graduated scale with a central target.
- The examiner alternately covers each eye; the eye that still sees the target through the hole when viewing monocularly is identified as the dominant eye.
- The number visible on the chart when viewing with the non-dominant eye provides a measure of the strength of eye dominance.
Pros
- Quick and easy to administer
Cons
- Does not take into account the monocular view of the dominant eye
- Relies on verbal self-report, which may introduce subjectivity and consistency bias
Binocular sighting test (BST)
- The test uses small bead (b) and a ring (c), each 15 mm in diameter, suspended from the ceiling at a distance of 45 cm apart.
- A camera (d) is positioned so that its visual axis is aligned with the center of the bead and the ring.
- The person sits 155 cm away from the ring, with a pointer (a) mounted above their head to indicate the direction of their line of sight.
- The person is asked to adjust their head position until the bead and the ring appear visually aligned.
- A photo is then taken, and the direction indicated by the pointer is used to calculate an eye dominance score.
The method is described in Johansson et al. (J.Vis. 2015)
Pros
- Not influenced by hand or arm dominance
- Provides an objective measure, independent of self-report
Cons
- Shows little correlation with the classic hole-in-the-card test
- Head posture can affect the outcome
- Setup impractical for routine clinical use
Freiburg Ocular Prevalance Test
- A pair of shutter goggles, synchronized with a display positioned 4.5 meters away, produces separate visual inputs to the right and left eyes.
- The stimulus is a stereogram presenting two triangles. The one pointing downward appears farther, and the one pointing upward that appears closer.
- The person adjusts the position of the triangles until they appear visually aligned.
- A virtual line connecting the two triangles intersects the interocular axis at a point between the eyes.
- The location of this intersection provides a measure of eye dominance.
This method is described by Kommerell et al. Vis. Res. 2003
Pros
- Not influenced by manual habits such as hand or arm dominance
- Provides an objective, non–self-reported measure
Cons
- Difficult to set for different distances
- Requires specialized hardware, including shutter goggles and synchronized display
Two cameras ocular dominance (2COD)
- A mechanical setup holds a circular transparent target positioned 10 cm in front of a display and 50 cm away from the person being tested
- The person uses a mouse to adjust the position and size of an alignment disc shown on the display.
- The person aligns the transparent target with the on-screen alignment disc under three viewing conditions: one binocular and two monocular.
- The person aligns the transparent target with the on-screen alignment disc under three viewing conditions: one binocular and two monocular.
- From the positions of the alignment circles across conditions, a precise, continuous eye dominance score is calculated, with positive values indicating right-eye dominance.
The method is described in Notaro et al. Behav Res 2025
Pros
- An objective, non–self-reported measure
- Easy to use with children
- Based on a computational model of visual processing
- Has a high precision and reliability
Cons