Speaking in Westminster following the Health Select Committee, Julie Bailey, who set up the Cure The NHS campaign group after her mother Bella died at Stafford Hospital in 2007, said Sir David's evidence was "shameful" and "embarrassing".
"That man is an absolute disgrace," she said.
Asked about suggestions that he would stay in post to lead reform of the NHS, she replied: "I think it's just laughable. He is desperate to carry on in his job."
She added: "We need to get rid of him. Nothing will change. He is part of the problem, not the solution."
More top news
Two students who wrote a sonnet to Tesco after their local store stopped selling their favourite popcorn have received a poetic reply.
Tina Drayson posted CCTV footage on her Facebook page on Friday. It shows two men leaving the property in Cranleigh in Surrey at 4:30pm.
Friends of a 15-year-old girl from Smethwick who died after losing her battle with cancer are paying tribute to her.