Dame Jo Williams has denied that she decided to resign as CQC chair as a result of difficulties in her relationship with a board member.

The former Mencap chief executive had faced calls for her resignation since she unsuccessfully tried to have non-executive director Kay Sheldon sacked after she gave evidence critical of the CQC’s leadership to the Mid Staffordshire Foundation Trust public inquiry. Then health secretary Andrew Lansley declined Dame Jo’s request.

On Friday Dame Jo announced she would stand down when a replacement was found.

During her appearance at the CQC’s annual accountability hearing with the Commons health committee this week, four days after she announced her resignation, Dame Jo was asked if the issues with Ms Sheldon had been a factor in her resignation.

She admitted it had been “extraordinarily complex and difficult” to make sure the board was working effectively over the past 12 months but said that was not the reason.

“What I said when I told the secretary of state I was standing down [is] I was pleased David [Behan] had moved into the job, I was confident that with the new strategy there was an opportunity to really move forward, to go from strength to strength, and after four years [it was time for me] to step back,” Dame Jo added.

Andrew Dilnot, chair of the commission on funding of care and support; Sir Christopher Kelly, former permanent secretary of the Department of Health; and current permanent secretary Una O’Brien all paid tribute to her leadership.

Ms O’Brien said: “Jo has shown sustained loyalty and commitment to the organisation, and to the patients and the public its serves. She is leaving the CQC well prepared for the next phase of its development.”

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