Harvard Medical School's Dr. Jerome Groopman came up with the idea for his book "How Doctors Think" while watching medical students make snap judgments while diagnosing patients. Groopman talks about how doctors get diagnoses right and sometimes wrong.

Almost 18 months after Hurricane Katrina devastated the Gulf Coast, thousands of its victims are still without health care. In the first of a two-part report, NewsHour health correspondent Susan Dentzer looks at how doctors are providing some temporary relief.