The question I ask myself is WHY have Dr Foster and the Care Quality Commission (CQC) appear to have drawn rather different conclusions about the state of the NHS ?
The two organisation do different things.
The CQC is the government's NHS inspectorate, which carries out a comprehensive monitoring programme of all NHS trusts.
Its rating system is based on a wide range of criteria, which includes patient safety and mortality rates, but also factors such as patient experience, access to services, efforts to improve public health and financial management.
Dr Foster is a company which works with the NHS Information Centre in public-private joint venture to study the sole issue of patient safety.
Both use comparable data on death rates - a measure known as hospital standardised mortality ratios , based on whether the death rate at a trust is above what could reasonably be expected, taking into account the mix of patients' ages and severity of disease .
In truth, the NHS is such a vast and complex monolith that no single monitoring body could ever hope to get a completely accurate picture of everything that goes on.