Forrest report

Last reviewed 06/2022

In 1985, Professor Sir Patrick Forrest was commissioned to evaluate the potential benefit of breast screening. His recommendations drew on studies undertaken in New York, Sweden, and the Netherlands.

In 1963, the USA health insurance plan study randomised 80,300 women aged 40-64 years between screened and control groups. Using two-view mammography with clinical examination, the screened group showed:

• 30% reduction in mortality after 10 years
• 23% reduction in mortality after 18 years

In 1977, the Swedish two-counties trial randomised 162,891 women aged over 40 years between screened and control groups. Using mammography initially, with clinical examination if the radiographs were suspicious, results for the screened group showed:

• 30% reduction in mortality after 8 years

The Forrest Committee concluded that high-quality mammographic screening had the potential for reducing the mortality from breast cancer in women over 50 years of age by 30%. Evidence for the effectiveness of clinical or self examination alone was not substantiated.