RT Journal
A1 Brenner DJ, Hricak H
T1 Radiation exposure from medical imaging: Time to regulate?
JF JAMA
JO JAMA
YR 2010
FD July 14
VO 304
IS 2
SP 208
OP 209
DO 10.1001/jama.2010.973
UL http://dx.doi.org/10.1001/jama.2010.973
AB 
The average radiation dose to which persons in the United States are exposed has doubled over the past 30 years.1- 2 Although the average dose from natural background sources has not changed, the average radiation dose from medical imaging has increased more than 6-fold.1- 2 Medical imaging now contributes about 50% of the overall radiation dose to the US population, compared with about 15% in 1980.2