U.S. diagnostic reference levels parallel those of other countries

The diagnostic reference levels (DRLs) for the 10 most common adult CT exams performed in the U.S. match those of many other countries, according to an article published online January 19 in the Journal of the American College of Radiology.

In a follow-up study, first author Priscilla Butler and colleagues compared U.S. DRLs previously reported by Kanal et al with DRLs from different countries, including Japan, Australia, Canada, several individual countries in the European Union, and the European Union as a whole. The researchers found the DRLs to be similar among these nations.

The U.S. DRLs never ranked as the highest for any of the primary adult CT exams studied, and the country's average CT dose index volume (CTDI_vol) was lowest among all countries for noncontrast head CT exams.