Many potential clients who contact us about a case emphasize that, in their case, the medical negligence was clear or egregious. Of course, proving that a medical provider was negligent is the first step in a case. But the second step – proving causation – is often the more difficult burden to meet. In every medical negligence case, the claimant has the burden of proving that a particular act or acts of negligence caused a specific harm. In many medical negligence cases, the initial condition or harm was present before the negligence, and the claim is that the provider failed to diagnose it, thus delaying treatment.

A common example is a delay in diagnosing cancer. The cancer was present before the provider missed signs and symptoms (such as by misreading a mammogram or overlooking a lump). When the cancer is finally diagnosed, it is claimed that the delay in diagnosis and treatment allowed the tumor to grow to a different size or stage and thus caused damage, i.e., required more extensive treatment and/or worsened the prognosis. The longer the delay, the better the chance or proving that it caused the damages. In many cases, however, the negligence becomes provable only as the signs and symptoms become more obvious, and by that time it may be that the delay is too short to allow proof of damages caused by the delay.

Proving causation is often more difficult because physicians are loath to testify about what might have happened with earlier diagnosis or treatment. To them, it is inherently speculative to express causation opinions in answer to a hypothetical question. In some cases, there is a body of statistics that can help in that process. For example, there are extensive breast cancer studies showing how the various stages of a tumor impact prognosis (usually expressed in terms of five-year survival). In many other instances, that body of statistics is absent. For example, there is less statistical evidence to support a claim that a four-hour delay in diagnosing an epidural spine infection resulted in the patient’s paralysis, or that initially missing an abdominal aortic aneurysm resulted in the patient’s death.

All medical negligence cases require that all three elements – negligence, causation, and damages – require expert medical testimony. The difficulties and cost of obtaining that expert testimony is one of the reasons why many attorneys do not take on medical/legal cases.