CHICAGO (AP) — Physicians may choose riskier treatment for themselves than they'd recommend for their patients, according to a study that highlights a need for candid discussions about patients' preferences.

The findings are important because patients faced with difficult medical decisions often ask their doctors, "What would you do?" The answer reflects the doctors' values — not necessarily those of the patient. Doctors should know what their patients value most before giving advice, and patients should ask doctors the reasons behind their answers, said study author Dr. Peter Ubel, an internist and behavioral scientist at Duke University.

For example, not all cancer patients would want life-prolonging treatment if it means suffering through horrible complications — and their doctors should know that, Ubel said.