Factors affecting decreasing radiation dose for mammography in North Carolina after 2002: an analysis of Food and Drug Administration annual surveys.
OBJECTIVE
We sought to determine which factors affected the decrease in average glandular dose recorded at the annual U.S. Food and Drug Administration Mammography Quality Standards Act inspections of mammography equipment in North Carolina from 2002 through 2005.


METHODS
Average glandular dose, half-value layer, kVp, equipment age, processing speed, and system speed for every mammography unit in the state were collected by Food and Drug Administration-trained state inspectors. A mixed-effect model was used to evaluate the changes of glandular dose over time and to identify the factors associated with these changes.


RESULTS
There was a statistically significant decrease in average glandular dose in North Carolina since 2002. Factors that were statistically significantly associated with this effect were changes in kVp, equipment age, processing speed, and system speed.


CONCLUSIONS
Average glandular dose for mammography has decreased in North Carolina after 2002. This change is probably at least partially due to the cumulative effect of direct intervention by mammography consultants and statewide educational seminars on mammography quality control.
Kuzmiak
Cherie M
CM
Department of Radiology, University of North Carolina Lineberger Comprehensive Cancer Center, Chapel Hill, NC 27599-7510, USA. cherie_kuzmiak@med.unc.edu
Pisano
Etta D
ED
Chung
Yeonseung
Y
Britt
Gerald G
GG
Burns
Barry
B
Cole
Elodia
E
D000847:Annual Reports as Topic; D004867:Equipment Design; D005260:Female; D019538:Health Care Surveys; D006801:Humans; D008327:Mammography / Q000295:instrumentation / Q000592:standards*; D009657:North Carolina; D011785:Quality Assurance, Health Care / Q000379:methods; D011829:Radiation Dosage; D014481:United States; D014486:United States Food and Drug Administration