1. Consultant radiologist, Breast Unit, Royal Bolton Hospital, Bolton, UK (Current address: The Nightingale Centre and Genesis Prevention Centre, University Hospital of South Manchester, Wythenshawe, Manchester, M23 9LT, UK)
2. Consultant radiologist, Breast Unit, Royal Liverpool University Hospital, Liverpool, UK
3. Consultant radiologist, Breast Screening Unit, Lancaster Royal Infirmary, Lancaster, UK
4. Consultant radiologist, Thirlestaine Breast Centre, Cheltenham, UK
5. Consultant radiologist, Cambridge Breast Unit, Addenbrooke's Hospital, Cambridge, UK
6. Screening lead, NHS North West, Manchester (Current address: NHS England, Lancashire Area Team, Preston Business Centre, Watling Street Rd, Preston)
7. Statistician, Biostatistics Group, University of Manchester, Manchester (Current address: MRC Centre for Paediatric Epidemiology and Biostatistics, UCL Institute of Child Health, 30 Guildford Street, London)