A patients' group has criticised the Healthcare Commission for not ordering an inquiry into poor standards of elderly care highlighted at a hospital.
The Panorama programme showed one patient being left to die
A three-month investigation by the BBC's Panorama programme uncovered a series of failings at the Royal Sussex County Hospital in Brighton.
A Healthcare Commission team concluded no formal investigation was needed after a visit in July.
A patients' forum linked to the NHS trust said it was "shocked".
Janice Kent is vice-chair of the Patient and Public Involvement Forum of the Brighton and Sussex University Hospitals NHS Trust.
She said: "There were an awful lot of findings about improper treatment of the elderly."
Ms Kent said there should be an inquiry into issues of "poorly-trained staff and inappropriate care".
"I have heard that relatives [of the elderly patients] are quite upset," she added.
The Healthcare Commission team said that good progress had been made in "improving the quality of patient care on medical wards".
Spokesman Jon Billings said: "There is some further progress needed and we will be working with the Surrey and Sussex Strategic Health Authority to follow up on action plans and monitor the trust's progress."
The NHS trust said: "We welcome the Healthcare Commission's decision not to launch a formal investigation.
"That does not detract from... ensuring [that] a good standard of care for our patients, whatever their age, is a priority for this organisation and our staff."