We doctors don't all approach sickness or dying the same way. Some of us are bound by simple statistics whereas others hold out for medical miracles.

But most of us have a more realistic notion of what to expect than the public we serve.

A study from the University of Pennsylvania in 2003 published in the Journal of the American Geriatrics Society surveyed 1000 elderly physicians and found that 64 percent had established advanced directives. This compared to only 20 percent of the general population.   

Doctors may be more savvy about what end of life care really entails, and when we have slim chances we may not be as willing to opt for aggressive care.

But a British study from 2010 published in the Journal of Medical Ethics showed that many doctors are influenced by their religious beliefs (as opposed to just health statistics) when giving advice on end of life care.

Meanwhile, our patients are constantly being misinformed by TV regarding what they can expect when they become seriously ill.  Another recent study revealed that CPR is portrayed on TV as being successful 75% of the time when in reality it is only 8 percent who survive more than a month. The public has a glorified view of what end of life care is really about until they are shocked to experience it in themselves or a loved one.

Since technology is ever changing, our chances for survival are often tied to the latest science. Doctors are more up on options and expectations than the public at large and may be more realistic based on actual knowledge of probabilities.

Whether your doctor is bound by his or her faith, science, or both, I think a good starting place for patients when considering end of life planning is to say to your doctor, "What would you do if you were me?"

Dr. Marc Siegel  is a professor of medicine and medical director of Doctor Radio at NYU Langone Medical Center. He is a member of the Fox News Medical A Team and author of "The Inner Pulse; Unlocking the Secret Code of Sickness and Health."

Dr. Marc Siegel, a practicing internist, joined FOX News Channel (FNC) as a contributor in 2008..