The financial and personal ramifications that come when a doctor apologizes to a patient.

When you're a doctor, you sometimes have to come to terms with making a mistake: giving a patient the wrong diagnosis or the wrong treatment, causing an injury, or perhaps something worse.

In one case I still think about, Andy (I've changed his name to protect his privacy) was a healthy teenager with migraines. "Take 600 milligrams of ibuprofen to start, and if that doesn't work, I'll prescribe something else," I told him. But in the month that followed, Andy's headaches grew worse.

I found nothing abnormal when I examined him. When I reviewed his records, I noted that he was taking anxiety medication prescribed by a psychiatrist. Perhaps that could be causing his symptoms, I thought, so I referred him back to psychiatry and to a neurologist before sending him home.

The next morning, I received a message from the emergency room. After his appointment, Andy had had a seizure in a store. In the emergency room, a doctor noticed something important when he looked at Andy's eyes with an ophthalmoscope: swelling of the optic disc, located in the back of the eye. Papilledema, as it is called, is a cardinal sign of increased pressure inside of the head. Had I seen it, I would have done exactly what the E.R. doctor did—ordered a stat CT scan, which revealed that Andy had deposits of fluid in his brain. Had it worsened, the pressure could have caused Andy's brain to herniate down into his spinal cord, which may have killed him. When I had examined Andy's eyes the same way, I missed the papilledema.

There are at least 25 definitions of the word error in medical literature. But the regret, fear, shame, and self-loathing I felt were all the definition I needed. How could I have done this?

Depending on what estimate you choose to go by, medical errors kill as many as 100,000 people each year. Doctors, nurses, and other health care providers make many more nonlethal mistakes. Studies tell us that patients—understandably—want to know when a mistake has been made with their health, and several professional organizations, including the American Medical Association, say doctors should disclose screw-ups. Nevertheless, there is a long-standing culture of concealment in medicine. While outside observers often attribute it to our fear of being sued, there's something more: Doctors don't like to admit they are fallible—it cracks our visage of authority.

In recent years, however, there has been a shift toward full disclosure—even toward apologizing for our mistakes. Despite physicians' resistance, this change has helped regain our patients' trust and prevented malpractice suits.

We didn't start disclosing and apologizing out of the goodness of our hearts. Like most changes in medicine, a series of events had to nudge us along. First came the Institute of Medicine's 1999 report "To Err Is Human," which contained that oft-cited statistic of 100,000 deaths and lifted the veil from our culture of concealment (although more than a few people dispute that number). In 2001, the Joint Commission, an organization that accredits hospitals—the medical equivalent of the Good Housekeeping seal for consumer products—mandated that hospitals disclose unanticipated medical outcomes. States entered the debate, too, when they began trying to encourage transparency by passing "apology laws," some of which make a statement admitting fault inadmissible in court, though these laws do not make a physician immune to a malpractice suit. Today, 35 states have laws protecting doctors' apologies and statements of regret.

Apologies have had a positive impact on doctors, patients, and hospitals. In 2001, the University of Michigan Health System adopted a policy for handling medical errors that centered on the principle of disclosure and apology. After one year, the hospital saved $2.2 million in malpractice claims, and the savings have continued. (The University of Michigan's emphasis on disclosure and apology is just one part of its policy. It also quickly compensates patients for any harm done, which has probably saved money by cutting legal expenses.)

Literature suggests that a simple apology won't keep a wronged patient from turning to a lawyer—just look at this study from September. Dr. Albert Wu of Johns Hopkins and his colleagues showed 200 volunteers randomly selected videos simulating doctors disclosing an error to a patient. Wu and his team varied the extent of the apology (full, nonspecific, none at all) and acceptance of responsibility (full, none). Patients responded more favorably to physicians who apologized and took responsibility for a mistake. But even subjects whose scenarios came with a full apology and disclosure didn't reconsider their desire to seek legal advice.