Results of the first round of a demonstration pilot of screening for colorectal cancer in the United Kingdom

Your recent publication1 highlighted the potential for screening for
colorectal cancer by testing for faecal occult blood. One important
factor not referred to, but previously described2 relates to the potential
importance of the presence of colour vision deficiency (“colour
blindness”), a disorder affecting around 8% of the male population. In
our study, some doctors, especially those with more severe colour vision
deficiencies, had difficulty in detecting blood in stool specimens. It
may be of importance that such doctors should be aware not simply of the
presence of colour vision deficiency, but of its severity. Furthermore,
the use of technologies such as faecal occult blood testing may be an
important technology by which the lack of confidence reported by doctors
with colour vision deficiency2 might be addressed, to the overall benefit
of patient care.

Yours sincerely,

1. UK Colorectal Cancer Screening Pilot Group
Results of the first round of a demonstration pilot of screening for
colorectal cancer in the United Kingdom
British Medical Journal 2004 329 133-138

2. Campbell JL, Spalding A, Mir F, Birch J
Doctors and the assessment of clinical photographs. Does colour blindness
matter?
British Journal of General Practice 1999 49 459-461

Competing interests:
None declared