The chief executive of the Belfast Health Trust has said he accepts the buck rests with him for the failings in patient care at Muckamore Abbey Hospital.
However, Martin Dillon said he would not resign.
In his first interview since news of the Muckamore scandal broke, Mr Dillon said he was determined to put things right.
He met with the families of 25 patients on Monday night.
Mr Dillon discussed giving them more of a say in the running of the County Antrim hospital, which treats people with severe learning disabilities, mental health needs or challenging behaviour.
"Some of the care failings in Muckamore are a source of shame, but my primary focus is on putting things right," he said.
"I'm the accounting officer, the buck rests with me, which is why I am resolved to make things right. We have let families down and we will put this right."
In December, BBC News NI revealed details of a confidential review about the protection of vulnerable patients.
The report concluded that patients' lives had been compromised and it charted a series of catastrophic failings and found there was a culture of tolerating harm.
CCTV footage revealed harrowing incidents of physical and mental abuse of some patients who were unable to speak out for themselves.
A police investigation continues into allegations of abuse at the hospital.
Nineteen health professionals including nurses remain suspended.
The BBC understands one senior manager is on long-term sick leave while another has retired.
"I have been very clear, any member of staff, whether a practitioner or a manager who is found responsible for wrongdoing will be held to account by my organisation," Mr Dillon said.
"Incidents witnessed on CCTV were not reported to management and site management - they were kept invisible from management."
'Huge learning points'
Mr Dillon said the report into Muckamore pointed to a subculture that had developed where unacceptable practice began to be tolerated.
"It may be that when you have an institution like Muckamore where staff have been there a long time a complacency sets in," he said.
"The report also highlights the fact that while patients make very many allegations of abuse, there probably was a tendency on the part of my organisation not to lend credibility to those.
"So those are all huge learning points for this organisation."
He said he accepted in hindsight that the trust should have informed the Department of Health sooner.
"I accept there was a delay in our reporting of some of these matters to the Department of Health," he said.
"But the reason for that was that there was a delay in these matters coming to the attention of very senior management."
Mr Dillon said Monday night's meeting with the families had been "very good" and "very constructive".
"Tonight was only the latest in a series of engagements with the families and carers," he said.
"Our full-time carer consultant has agreed on the back of tonight's meeting to now work up options with the families as to how they could have that more direct role in the governance and oversight of Muckamore Abbey Hospital."
Former health minister Edwin Poots told the BBC's Good Morning Ulster programme he would support a public inquiry into the alleged abuse of patients at Muckamore Abbey.
Mr Poots, whose brother was a patient at the hospital, says there needs to be better communication between the Belfast Trust and the Department of Health.
"We need to have more answers to questions," said the Democratic Unionist Party MLA.
"The families will want to know what really went on at Muckamore and having the investigation carried out in a public manner will allow them that knowledge and confidence.
"The trust needs to be honest when they have problems and let the department know straight away because teamwork will help overcome these issues."