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
The elderly woman's son complained to the council that his mother had been deprived of her liberty in an 'unprecedented' legal case.
A suspected drunk driver ploughed into a crowd during Mardi Gras celebrations in the southern US city.
The singer had been tweeting in support of migrants when she was bombarded with abusive messages.