'Vutest' tests to a 6/9 (20/30) threshold. Scores below 75%
indicate that 3 or more 6/9 letters were incorrectly identified.
Right and left eyes are tested separately by manual occlusion
of the non-tested eye.
An Amsler grid is presented to each eye separately. Scores
below 75% indicate that there was some distortion or break
in the Amsler grid.
The two eyes are dissociated horizontally and then vertically,
perception of a double after-image indicating retinal slip
requiring binocular vision assessment. Phoria scores below
75%, indicate any reported degree of disassociation.
Letters are presented to the user in random order around
the screen. Failure to recognise the letters indicates
a difficulty which may be due to a field defect, binocular
vision imbalance, distressed scanning, and accommodational
Colour vision scores below 75% indicate a failure of at least
one colour confusion plate. The user does not fail 'Vutest'
if the score is below 75%. Failure of colour vision is
not in this case considered a definite reason for referral
to an optometrist.