The Care Quality Commission is set to introduce radical changes to the way hospitals in England are inspected.
Following on from the review carried out by Sir Bruce Keogh, which found that 14 trusts had high mortality rates, the changes will be introduced by the end of the month.
As part of the changes the CQC introduced a new method to assess the level of risk of poor care at each trust, and four London NHS trusts are amongst the worst six in the country.
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