To succeed with a claim for compensation for medical negligence, it will be necessary to prove both that the care and treatment given were negligent and that your injury has been suffered as a result of that negligence.
A doctor or nurse is negligent if their care, management or treatment of a patient fell below an acceptable level that no responsible body of medical or nursing opinion, as the case may be, would condone. If there is a responsible body of professional opinion that would support the conduct of the doctors or nurses involved, then there was no negligence, even if most doctors or nurses would have acted differently and with a better outcome.
Even if it is proved that the treatment was negligent, this alone would not be enough to win a case. A claim can only succeed if it can be proven that it is more likely than not that the negligence caused the patient to suffer injury.
The usual test is whether “but for” the negligence, the injury would not have occurred. This involves a comparison of the likely outcome without negligence, and the actual outcome after negligence has occurred. The difference between the two outcomes is “the injury”. If without the negligence, there would have been the same outcome from the treatment then the claim will fail.