Evidence given to the Mid Staffordshire Foundation Trust public inquiry by witnesses from the Care Quality Commission has been called into question after the inquiry team received an anonymous tip off.

The inquiry was alerted to the existence of an internal review comparing some of the evidence given by the CQC on how its processes and procedures work to how they work in practice.

An investigation was launched by the inquiry solicitors and as a result three new witnesses have been called. Meanwhile, CQC director of intelligence Richard Hamblin has been called back and will be given the opportunity to comment on their evidence.

The new witnesses are the CQC’s head of operational intelligence Sampana Banga, senior operations analyst Rona Bryce and south-east London regional intelligence officer Lauren Goodman. They will appear during the final week of inquiry hearings.

This afternoon inquiry counsel also confirmed that due to his ill health former trust chief executive Martin Yeates will not be appearing before the inquiry and will instead have his statement read to the inquiry on 3 October.

On the same day former chair of governors Toni Brisby will give evidence to the inquiry via a video link.

Chairman Robert Francis QC told the inquiry he had taken the decision to allow her to give evidence in this way after receiving representations that she was in poor health.

Mr Francis also granted an application from campaign group Cure the NHS that former trust head of governance Trudi Williams be called to appear before the inquiry. The inquiry heard Ms Williams, a registered nurse, is now in a similar position at the Dudley Group of Hospitals Foundation Trust.

Former trust nurse and whistleblower Helene Donnelley is also due to appear during the final week of hearings, as is trust board secretary Kate Levy and former trust solicitor Stuart Knowles, who is now assistant coroner for Staffordshire.

The hearings will be followed by a series of seven seminars beginning on 13 October and covering topics including regulation, nursing and leadership.

The seminars are invitation only but the public will be able to attend on request. They will be held at locations in Leeds, Manchester, London and Stafford and are designed to give the inquiry an opportunity to speak to a range of interested parties before drawing up its recommendations.