First, there must be evidence, from a qualified expert, that the care provided by the health care provider, was negligent or "below the standard of care." Standard of care is basically defined as what a reasonably prudent health care provider would do in the same or similar circumstances.
Second, it must be shown, with a qualified expert, that the negligent care by the doctor, nurse or whatever type of health care provider is involved, was the cause of the injury. For example, in a case involving a newborn with a brain injury where the allegation is failure to deliver the baby in a timely manner, it must be shown that the delay in the delivery was the cause of the brain injury, rather than some other explanation.
In evaluating a potential medical case, the records are accumulated and then provided to an expert who has expertise in the field of medicine involved to determine whether there is sufficient evidence to prove the negligence and the link to the injury. Often, multiple experts with different specialties must be involved to prove the different aspects of the case.
Experience in identifying the key medical issues present in a case and experience in consulting with the appropriate medical experts are important to the evaluation and successful pursuit of medical negligence cases.