ATLANTA (AP) -- New government statistics show the rate of high-tech diagnostic imaging has dramatically increased since the mid-1990s.

From 1996 to 2007, the frequency of MRI, CT or PET scans done in emergency rooms quadrupled. And the frequency nearly tripled for doctor offices and outpatient hospital visits.

The Centers for Disease Control and Prevention says there are many more scanning machines available today. But health officials and others worry about the safety and cost of all that scanning.

The CDC detailed the increases in a report released Wednesday.

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