Failures in elderly care at two Welsh hospitals highlighted in a damning report are "unacceptable", the older people's commissioner for Wales says.
Sarah Rochira said health boards across Wales must ensure they know what is going on in their wards and act quickly to put problems right.
The report was the result of a review prompted by the neglect of Lilian Williams, 82.
Unannounced spot checks will now be carried out at hospitals across Wales.
Ms Rochira told BBC Radio Wales the fact problems went undetected at the Princess of Wales Hospital in Bridgend and Neath Port Talbot Hospital for three years was "disturbing".
"It appeared the board didn't know what was going on in their beds, in their wards, and that must be unacceptable," she said.
"Across Wales [health] boards are trying very hard to better understand what is going on their wards, but trying very hard isn't good enough is it?
"Every health board must be asking themselves a simple question, 'could this be happening in my hospital?' and if they don't know the answer to that they need to go out and look for themselves."
Regulation and inspection
Her warning comes a day after the publication of the Trusted To Care report, which found several failings at the two hospitals run by Abertawe Bro Morgannwg University Health Board.
Among the issues highlighted were patients being told to soil themselves, an ignorance of dementia needs and poor professional behaviour.
Health Minister Mark Drakeford said he was "shocked" by its findings and apologised to the patients and families affected.
He has now ordered a further review of elderly care, including random spot checks at hospitals across Wales.
Ms Rochira said incidents of poor care could be more wide spread and said it was up to health boards to reassure patients that was not the case.
She also questioned why the failings were not picked up by the regulator Health Inspectorate Wales, which carried out an inspection during the period the poor practice was happening.
"Do we have strong enough regulation and inspections of health care in Wales?" she said.
"It has to be one of the questions we ask ourselves, not just in relation to these hospitals but across Wales."
Tina Donnelly, director of the Royal College of Nursing in Wales, told Radio Wales the organisation did not condone poor care and agreed those responsible must be held accountable.
But she said poor practice could be down to a lack of dedicated elderly care wards in Wales and a shortage of nurses who are trained specifically to care for those with complex needs.