title: First results on mortality reduction in the UK Trial of Early Detection of Breast Cancer. UK Trial of Early Detection of Breast Cancer Group.
abstract: Between 1979 and 1981 the UK Trial of Early Detection of Breast Cancer enrolled women aged 45-64 living in eight locations in the United Kingdom. Annual screening by clinical examination of the breast, with mammography in alternate years, was provided over 7 years for 45,841 women; 63,636 were offered teaching in breast self-examination and were provided with a self-referral clinic; and 127,117, for whom no extra services were provided, form a comparison population. Over the 7 years from the start of the trial a reduction in the risk of dying from breast cancer in women offered screening relative to that in the comparison population was observed. The reduction was 14% (RR 0.86, 95% CI 0.69-1.08) when no allowance was made for underlying differences in breast cancer mortality between the populations, but rose to 20% (RR 0.80, 95% CI 0.64-1.01) when adjusted for differences in pretrial mortality rates. These differences fall short of statistical significance. No reduction in mortality was observed during the first 5 years but thereafter the gap widens. These results, though in themselves inconclusive, are consistent with the hypothesis that screening can achieve a worthwhile mortality reduction. No difference in mortality has so far been observed between women offered teaching in breast self-examination and the comparison population.
mesh_terms: D001943:Breast Neoplasms / Q000175:diagnosis / Q000401:mortality / Q000517:prevention & control*; D002986:Clinical Trials as Topic; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008327:Mammography; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D010173:Palpation; D012648:Self Care; D006113:United Kingdom