TRENTON, N.J. -- A significant number of doctors say they do not feel obligated to tell patients about medical options they oppose morally, such as abortion and teen birth control, and believe they have no duty to refer people elsewhere for such treatments, researchers say.

The survey of 1,144 doctors around the country is the first major look at how physicians' religious or moral beliefs might affect patient care.

The study, conducted by University of Chicago researchers, found that 86 percent of those responding believe doctors are obligated to present all treatment options, and 71 percent believe they must refer patients to another doctor for treatments they oppose. Slightly more than half the rest said they had no such obligation; the others were undecided.

"That means that there are a lot of physicians out there who are not, in fact, doing the right thing," said David Magnus, director of Stanford University's Center for Biomedical Ethics.

An American Medical Association policy statement says doctors can decline to give a treatment sought by an individual that is "incompatible with the physician's personal, religious, or moral beliefs." But the physician should try to ensure the patient has "access to adequate healthcare."

The survey did not examine whether these doctors act on their beliefs -- that is, whether they actually withhold information or refuse to refer patients. But the researchers calculated that tens of millions of Americans might be going to such doctors.

"Conscientious objection is fine . . . as long as it doesn't conflict with the rights of the patient," Magnus said. "You can't abandon the patient or essentially coerce the patient by saying you won't do the procedure or refer them to someone else."

The study, which was partially funded by the Robert Wood Johnson Foundation of Plainsboro, N.J., is published in today's New England Journal of Medicine. It was led by Dr. Farr Curlin, a University of Chicago ethicist and internist. The findings were based on a survey mailed to 1,820 practicing US family doctors and specialists, chosen randomly from a national database; 63 percent responded.

Doctors who described themselves as very religious, particularly Protestants and Catholics, were much less likely than others to feel obligated to tell patients about controversial treatments or refer them to other doctors, and were far more likely to tell patients if they had moral objections.

Overall, 52 percent of those responding said they oppose abortion, 42 percent opposed prescribing birth control to 14- to 16-year-olds without parental approval, and 17 percent objected to sedating patients near death.

Female doctors were much more likely than male ones to feel obligated to refer patients for treatments they personally oppose, far less likely to present their own objections to a patient, and slightly more likely to disclose all treatment options.

For more information, go to nejm.org or ama-assn.org.

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