Effectiveness of Policies on Reducing Exposure to Ionizing Radiation From Medical Imaging: A Systematic Review.
OBJECTIVE
The use of medical imaging has expanded greatly in the past three decades, raising concern about potential unwanted carcinogenic harms associated with exposure to ionizing radiation among patients. This study summarizes evidence of efficacy of interventions that have prompted policies, and structural-level interventions aimed at reducing radiation dose and risk of cancer, especially among women.


METHODS
Using standard terms, we conducted searches in MEDLINE, Scopus, and Web of Science, and de-duplicated retrieved citations. We hand-searched the reference section of eligible studies and contacted radiology experts to identify studies missed from electronic searches. Two reviewers screened retrieved citations based on predefined eligibility criteria, to identify relevant studies, extract key information from each, rate the quality of evidence, and summarize data in tabular and graphical format.


RESULTS
From a total of 1,543 unique citations identified from all sources, 16 were included for data extraction. Half of the studies focused on reduction of ionizing exposure from CT, and half on x-ray or fluoroscopy. Identified interventions were broadly categorized as: policy or structural intervention (two; 13%); multipronged (four; 25%); dose-feedback system (five; 31%); provision of training (four; 25%); and quality-control audit (one; 6%). In general, multipronged programs had a higher range for dose reduction (22%-74%), followed by policy/structural interventions (37%-50%).


CONCLUSIONS
Existing evidence on the effectiveness of policies aimed at reducing patient radiation dose is disperse and low in quality. Compared with other approaches, multipronged efforts may offer more patient protection.
Department of Radiology, University of California, San Francisco, San Francisco, California.
Ashesh
A
Thaker
Global Health Sciences, University of California, San Francisco, San Francisco, California; Department of Epidemiology and Biostatistics, Tehran University of Medical Sciences, Tehran, Iran.
Soodabeh
S
Navadeh
Philip R. Lee Institute for Health Policy Studies, University of California, San Francisco, San Francisco, California.
Hugo
H
Gonzales
Global Health Sciences, University of California, San Francisco, San Francisco, California; Philip R. Lee Institute for Health Policy Studies, University of California, San Francisco, San Francisco, California. Electronic address: mmalekinejad@ucsf.edu.
Mohsen
M
Malekinejad
D003952:Diagnostic Imaging / Q000706:statistics & numerical data*; D006291:Health Policy / Q000639:trends*; D006801:Humans; D038622:Internationality; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data / Q000639:trends; D000069079:Radiation Exposure / Q000517:prevention & control* / Q000706:statistics & numerical data*; D011835:Radiation Protection / Q000706:statistics & numerical data*; D011839:Radiation, Ionizing; D014057:Tomography, X-Ray Computed / Q000706:statistics & numerical data* / Q000639:trends
Systematic review; health policy; ionizing radiation; medical diagnosis; medical imaging