New scale measures impact of colour blindness on quality of life

Dr John Barry, Honorary Lecturer at UCL Division of Psychology and Language Sciences, has developed the first ever scale to measure the impact of colour blindness on quality of life.

Working in collaboration with the University of Birmingham Academic Unit of Ophthalmology, Dr Barry conducted a survey of 419 people with congenital colour vision deficiency, more commonly known as colour blindness. His findings conclude that colour blindness can significantly impact quality of life (QoL) for health, emotions, and careers. The results have been published in the journal BMC Ophthalmology.

Colour blindness affects around 8% of men and 0.4% of women. Dr Barry explained that, although many aspects of health, healthcare and modern life depend upon colour coding – for example, coloured medication, maps and graphs – the impact of colour blindness on everyday life has not previously been investigated.

The study began with an expert panel designing and developing a QoL questionnaire, which was then piloted on a focus group. Next, a sample of 128 men and 291 women completed the questionnaire online. The psychometric properties of the questionnaire were analysed using principal components analysis. The scores of both colour blind and normal-sighted participants, controlling for age and sex, were compared using matched t-tests.

The principal components analysis resulted in a questionnaire with three domains: QoL for Health & Lifestyle, QoL for Work, and QoL for Emotions. There was a significantly greater negative impact on QoL for colour blind people than normal-sighted people in all three domains.

Dr Barry hopes that the questionnaire could be useful in future clinical studies to measure changes in colour blind QoL in response to therapy, in conditions where colour vision is affected. In the journal article, he also discusses ways in which everyday problems related to colour vision might be reduced: for example, workplaces could avoid colour coding in graphs where a non-colour alternative is possible.

Colour blindness has been in the news throughout 2017 due to its impact on sport: in March, Gary Ballance, Yorkshire cricket captain, admitted he struggled to see the pink cricket balls recently introduced to the game. In June, the Football Association published guidance notes to create awareness of the problems created by using certain colours in football strips for football fans and footballers.