Nj. Wald et al., UKCCCR MULTICENTER RANDOMIZED CONTROLLED TRIAL OF ONE AND 2 VIEW MAMMOGRAPHY IN BREAST-CANCER SCREENING, BMJ. British medical journal, 311(7014), 1995, pp. 1189-1193
Objective-To compare one view (oblique) and two view (oblique and cran
iocaudal) mammography in breast cancer screening. Design-Randomised co
ntrolled trial. Setting-Nine breast screening centres in England. Subj
ects-40 163 women aged 50-64 attending their first breast screening ex
amination. Interventions-Women were randomised to have one view mammog
raphy, two view mammography, or two view mammography in which one view
was read by one reader and both views were read by another. Main outc
ome measures-Prevalence of cancer detected, recall rates, cost per can
cer detected, and marginal cost per extra cancer detected. Results-Two
view mammography detected 24% more women with breast cancer (95% conf
idence interval 16% to 31%) than one view mammography. Prevalence of d
etected cancer was 6.84 with two view mammography and 5.52 per 1000 wo
men with one view. The proportion of women recalled for assessment was
15% lower (95% confidence interval 6% to 23%) with two view (6.97%) t
han with one view (8.16%) mammography. The cost of two view screening
was higher (pound 26.46 compared with pound 22.00 per examination) but
the average cost per cancer detected was similar (pound 5330 compared
with pound 5310) and the marginal cost per extra cancer detected with
two views was similar to the average cost (pound 5400). Conclusion-Tw
o view mammography is medically more effective than one view; it detec
ts more cancers and reduces recall rates; it is also similarly cost ef
fective financially.