This information is not collected centrally.
Strict quality assurance is operated across the national health service breast screening programme at a cost of £4 million a year and the performance of local screening services is kept under close review.
Following concerns in relation to the North London Breast Screening Service, it was temporarily suspended on 29 December 2006.
In April 2007, a report by NHS cancer screening programmes into services in North London was passed to Enfield primary care trust, and it, together with other stakeholders, reviewed the report's findings and recommendations and developed an action plan for improvement. As a result, the screening service resumed on 14 May 2007 and is being closely monitored to ensure quality and safety.