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A high-speed Cat Scan at the newly-opened Berenson Emergency Department at Beth Israel Deaconess Medical Center sits empty July 16, 2001 in Boston, Massachusetts.

Will a CT scan save your life—or kill you? Researchers say that the level of radiation patients receive from the diagnostic test, sometimes 440 times that of a typical chest X-ray, could cause tens of thousands of cancer cases a year. To what end? There is no evidence that the scans prevent deaths. Should we abandon CT scans altogether? What is an acceptable level of risk?

Guest:

Gardiner Harris, public health reporter and science correspondent for the NY Times