The post you are reporting:
Cross charging is a very complex part of the NHS structure , it sort of depends who is requesting the action , I will give you a ( very clumsy ) example
A person sees the local mental health team , the mental health team request blood tests , the person goes to get the test at a Hospital , the Mental Health service is charged for the test and processing rather than the hospital bearing the cost because the test is requested by a non Hospital team , who do not have a contract with the Hospital to carry out these tests .
A person goes to an Out Patient apt at the hospital , the consultant requests blood tests , the Hospital bears the cost of the test and uses part of the consultants budget to pay for it .
A person has a sore throat , they dont want to wait to see the GP , they go to Hospital A nd E thye are seen and medication issued , the GP practice may be charged as this is not the service the hospital is commisioned to do . ( I dont believe that this is a wide spread practice but it is possible )
All of the above are inelegant and rather symplistic examples of the joys and delights of the structure of the NHS as it stands