hello there and welcome to the clinic
so today i have reintroduced the ishihara colour test
previously it created or induced some quality asmr for you but it also may have caused a
little bit of concern about what you could and couldn't see on the various plates so today
i'm going to explain what you should and shouldn't say depending on whether you have
a red green colour defect to help you relax and understand the test a little bit better
so as before we are using the 38 plate edition ishihara test here
there are various categories of plates to check for red green colour deficiencies
but it's important to remember that the ishihara
does not screen for tritan defects it doesn't screen for tritan defects okay
this is the most commonly used entry colour vision test for various worldwide industries such as the
aviation the railway or the armed forces so those industries will want to know if you have
passed the ishihara test okay and it's not ideal for grading the severity of your colour defect
this is where the city university test comes into play or the farnsworth d15
the farnsworth d15 test okay let's have a little look at the first plate
okay first up we have what's called the demonstration plate
a person with a total colour blindness will still see that on this plate
is the number 12. so it ensures that you are not malingering or giving me any grief
when we begin the colour vision assessment so everybody should say the number 12 there okay
so moving on to the next batch of plates these are what's known as the transformation plates
we have this one here
and this one here okay so somebody with a red green deficiency
may see a number three here instead of an eight a normal would see a six there
a red green defective may see the number five okay so that's the first batch of transformation plates
next up have a little look here do you see the number 29
or the number 70 29 is normal 70 is a red green defective potentially and for the next one
if you see 35 you may have a red green colour deficiency
a normal would see the number 57 there 57 57 okay
let's have a little look ah yes so we're still on the transformation plates
we have the number five for a normal and the number three for a normal layer
you may see a number two
or a number five there if you are a red green colour defective
now we have the last pair of transformation plates here
look what you see on this page and this page if you see 17 here
and the number 21 there you may potentially have a red green deficiency whereas a normal would see
15 and 74 74 okay
yeah that's the end of the transformation plates next up we have what looks like the
vanishing plates these are the vanishing plates so someone with normal colour vision would see
the number two
and the number six if you have a red green deficiency
there's a chance you may not see anything on those plates there
next set of vanishing plates
we have this one here
which is 97 and 45 you might not see either number there with a red green deficiency
do you see the number five and seven there with normal colour vision
excellent
this one here and this one here normal colour vision you should see 16
and there 73 73 okay
right things are going to be a little bit reversed now we are now on to the hidden plates
where somebody with normal colour visual system would see no number
this one here excellent so somebody with a red green deficiency may see the number five
and on here the number two
five and two
okay two more hidden plates
this one here this one here a defective may see the number 45 there
and the number 73 here so that is the final set of hidden plates there
okay now we are on to the diagnostic plates we have four numeral type diagnostic plates
we're trying to classify whether the defect is protan or deutan and the severity based
on whether you see one number both numbers or if one of the numbers is just partially seen
there we go so depending on what you say and how you see them
we can attempt to classify your red green colour deficiency
so i see this normally as 26 red and pink both equally bright
and here i see the number 42 equal and prominent
okay
two more diagnostic numeral plates here
that to me is the number 35 bright and equal each numeral and there 96. there's 96 bright and equal
so that is all five categoriesof the ishihara test
just continuing a little bit more we have the non-numeral plates
so we have another set of classification plates
using the tracing of the meandering lines there we can trace the meandering lines
based on whether you see one two or one of them partially we can then classify
as protan or deutan or strong or mild as the case may be
it
appears we have some more hidden ones there tracing which i see no meandering lines there
we have some we can see
non-numeral type
we have another two sets here
another two sets
there
we have some more here
and here
more here and here
and finally we have a non-numeral demonstration tracing plate which even with a total colour
blindness as we showed you on the very first plate we can do it in tracing form
right there on this final plate excellent
that is the end the ishihara test and the explanation
let's hope it has demystified some of your concerns and i'm sure you'll see it again used
in some more srp assessments okay so say goodbye to the ishihara test here in its protective casing
and you'll see it again next time