Outgoing HSE chief Brendan Drumm has said changes which are underway in the health system would deliver improved, but not perfect, child protection services.
Professor Drumm's comments came after child-protection charity Barnardos declared yesterday that the HSE was not fit to protect children.
He said international research showed that only 10% of serious abuse of children was reported to authorities.
In his last public appearance before leaving the HSE, Professor Drumm said major changes to the system were underway, although they would not make the system perfect.
"We found in child protection that there were huge differences in terms of how one part of the service performed on one part of the country to another part of the country with the same resource," he said.
He said practices were now being standardised across the country in a process that would take one and a half years to implement, which he said was a "massive change".
"Will the system then be perfect? I don’t think it will…but it can be a lot better," he said.