Benefit? Sounds more like a risk…..
In July 1985 a working group under Sir Patrick Forrest was invited by Ken Clarke (yes him, the same Ken Clarke as our current Ken Clarke) to look at the evidence on breast screening and decide what to do about it. It made its report - Breast Cancer Screening - in November 1986. The Government accepted it in full for implementation in early 1987.
Hence our current breast screening programme.