An investigation into the deaths of five children in hospital has still not provided a full explanation, grieving relatives said.

Sir John O’Hara QC chaired the Hyponatraemia Inquiry and heavily criticised the medical profession after finding that failures in patient care had been covered up.

It probed issues arising from the treatment of 15-year-old Conor Mitchell in May 2003.

His family said: “Conor was a beautiful child who lived life to the full. His disability did not define him in life and will not define him in death.

“The decisions made in Craigavon Hospital leading to his death and the decisions not to treat his death properly until required to by this Inquiry are all matters that are still unexplained.”

The inquiry report said there should be a law forcing doctors who give evidence to be candid and urged medics to stop putting their own reputations first.

Conor’s parents praised the inquiry for conducting a compassionate and professional investigation.

They said: “Their approach and consideration stands in stark contrast to the manner and attitude displayed by the parties involved in the treatment of the children nor the management or advisers they turned to for protection afterwards.

“The report published yesterday severely undermines the health service which is meant to be there to protect and treat all of us when we are ill and in particular the weakest in our society who place their utmost trust in the medical staff.”

They added: “While there are many hard working and professional people in those positions the way in which those identified have acted, their history of failings and deliberate evasion of the truth, at best, demeans us all.”

They said they have still never received any explanation for many of the failings in Conor’s treatment, receiving a less than fulsome acknowledgement and limited apology at the very last minute which they still believe was intended to prevent a public examination of any issues.

“The findings in the report about the lack of training of staff, the inconsistent treatment of children, the deliberate mis-information provided and the lack of proper leadership are shocking.”

They said improvement at Craigavon Area Hospital in Co Armagh fell short of what was needed.

Sir John was looking into the deaths of youngsters who were being treated at the Royal Belfast Hospital for Sick Children but in some cases had been transferred from other hospitals.

He said some medics had behaved “evasively, dishonestly and ineptly”.