By Nick Triggle
Health reporter, BBC News
There are nearly 30,000 children subject to child protection orders
Two thirds of hospitals do not routinely check if children are subject to child protection orders when they arrive injured in A&E, figures suggest.
Research by the Conservatives revealed confusion in the NHS in England about who could access such data and how.
The Tories described the findings as "deeply worrying".
NHS trusts said there needed to be more consistency and clarity. However, ministers said hospitals were not obliged to check up on every child.
Information on children deemed at risk and placed on a child protection plan is held by councils.
Designated people at hospital, usually senior managers and doctors, can request this information if they have concerns.
But the data obtained by the Conservatives, compiled from answers given by 104 hospital trusts to a freedom of information request, showed the systems in place varied from area to area.
Only one in seven hospitals was able to access child protection information online.
The rest had to rely on getting through to council officials on the phone or paper lists, which critics say becomes quickly out-dated.
Of those that did not carry out routine checks, some said they did not have access to child protection plans, while others said data protection laws did not allow staff to carry out checks.
The findings come just months after the Baby P case came to light.
The boy, who was on the "at-risk" register, died aged 17 months in 2007 with major injuries, including a broken back.
He had come into contact with health, social care and police professionals 60 times.
The inquiry into Baby P's death, which was published in December, highlighted the confusion among A&E professionals about access to data.
The issue of information sharing was also brought up during the investigation into Victoria Climbie, the eight-year-old who died in 2000 from abuse and neglect, despite coming into contact with a number of agencies.
Shadow health secretary Andrew Lansley said: "It is deeply worrying that some very basic checks to protect our most vulnerable children are not in place in A&E.
"Many hospitals are getting incoherent messages about what to do to prevent tragedies like the Baby P case from happening again."
Jo Webber, of the NHS Confederation, which represents hospitals, agreed there was confusion.
"The problem is that there are different systems in place and I think there does need to be more clarity.
"However, child protection does require staff to use their professional judgement and where they do have concerns they should be seeking the information."
She said the development of a central database for children in contact with social services, which is being rolled out later this year, would help.
However, it could be another five years before it is fully up-and-running.
Councillor John Merry, of the Local Government Association, said councils and emergency services would "continue to work hard" to improve the ways they worked together "to ensure children are protected as much as is humanly possible".
Health Minister Ben Bradshaw said: "There is no national requirement, and it would be unnecessary to routinely check every child admitted to A&E against the child protection register."
But he added that if staff suspected there was a child protection issue, there were "clear rules" that were "binding on all trusts".
"They include arrangements for checking if a child is subject to a child protection plan and mandatory training for staff," he said.