Not many people are fully examined for colour blindness, so it’s not surprising that some people can be partially colour blind and not know it – remember that red and green lights in traffic signals are in different positions on the pole, so colour isn’t always as important as it seems.

The use of the term colour blindness is a bit misleading, since people who are colour blind can see things just as well as anybody else – they’re NOT blind – they just can’t differentiate between some colours. The colours that present most difficulty are reds and greens, and then to a lesser extent yellows and oranges.

Colour blindness is somewhat sexist in that males and females aren’t equal, with about 10% of boys and only 0.5% of girls having the condition. Notice that it wasn’t necessary to say “suffering” from the condition, as many people who have colour blindness are able to manage well without other people being aware of their condition (but understandably they do become a little frustrated now and then).

How is Colour Blindness Perceived by the Community?

Very often colour blindness is perceived as a disability, and this leads to those having the condition to hide the fact. The Community needs to change this awareness and instead appreciate what can be done to enhance the lives of those who are disadvantaged by the way colours are used in everyday life.

All that people who have a degree of colour blindness want – the term “Defective Colour Vision” is preferred by the way – is to have things designed and systems built in such a way that colour is not o crucial importance.

What can be Done to Improve Things for Those with Defective Colour Vision?

Why not limit the use of colour in websites – particularly red – which is one of the colours that produces major problems remember.

And what about the forms that you fill out on the internet that when you make a mistake or omission, pop up with “You have not completed all data” – IN RED!! (Blue would be a much better colour to use).

Where possible in graphs and diagrams use lines in bold or dotted rather than colour, and give some thought to background colour. By far THE best graphic presentation still is black or grey on white, with use of bold or capitals for emphasis.

Colour blindness is inherited in most cases, so if you do find you have it to some degree, it’s always comforting to be able to blame your parents, in particular, your mother. The genetic deficiency is called an X-linked chromosome deficiency.  The defective X chromosome is supplied by the mother in most cases, with the sons exhibiting the problem, while daughters can be carriers and most of the time do not exhibit the problem. How sexist is that!

There are no known cures, but those with colour deficiency do learn to compensate effectively.  Research into using some filters to help in distinguishing between colours has shown some interesting results, but we will have to be patient on that.

Do You Think You Might have Defective Colour Vision?

It used to be necessary to visit an Optometrist or Ophthalmologist for a complete appraisal, and that is still the best option, but by way of introduction there are tests reproduced on websites that will give an indication.

The usual disclaimers apply of course, remembering that colours uploaded on to the website as well as reproduced on the computer screen may not be truly accurate.