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Diagnostic CT Scans: Assessment of Patient, Physician, and Radiologist Awareness of Radiation Dose and Possible Risks¹

¹ From the Department of Diagnostic Radiology (C.I.L., A.H.H., J.A.B., H.P.F.), Section of Emergency Medicine, Department of Surgery (E.P.M.), Department of Economics (H.P.F.), and School of Management (H.P.F.), Yale University, 333 Cedar St, TE-2, New Haven, CT 06520. From the 2002 RSNA scientific assembly. Received May 15, 2003; revision requested June 20; final revision received October 20; accepted November 19. Address correspondence to H.P.F. (e-mail: howard.forman@yale.edu).

	ABSTRACT

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 
PURPOSE: To determine the awareness level concerning radiation dose and possible risks associated with computed tomographic (CT) scans among patients, emergency department (ED) physicians, and radiologists.

MATERIALS AND METHODS: Adult patients seen in the ED of a U.S. academic medical center during a 2-week period with mild to moderate abdominopelvic or flank pain and who underwent CT were surveyed after acquisition of the CT scan. Patients were asked whether or not they were informed about the risks, benefits, and radiation dose of the CT scan and if they believed that the scan increased their lifetime cancer risk. Patients were also asked to estimate the radiation dose for the CT scan compared with that for one chest radiograph. ED physicians who requested CT scans and radiologists who reviewed the CT scans were surveyed with similar questions and an additional question regarding the number of years in practice. The ² test of independence was used to compare the three respondent groups regarding perceived increased cancer risk from one abdominopelvic CT scan.

RESULTS: Seven percent (five of 76) of patients reported that they were told about risks and benefits of their CT scan, while 22% (10 of 45) of ED physicians reported that they had provided such information. Forty-seven percent (18 of 38) of radiologists believed that there was increased cancer risk, whereas only 9% (four of 45) of ED physicians and 3% (two of 76) of patients believed that there was increased risk (²₂ = 41.45, P < .001). All patients and most ED physicians and radiologists were unable to accurately estimate the dose for one CT scan compared with that for one chest radiograph.

CONCLUSION: Patients are not given information about the risks, benefits, and radiation dose for a CT scan. Patients, ED physicians, and radiologists alike are unable to provide accurate estimates of CT doses regardless of their experience level.

© RSNA, 2004

Index terms: Computed tomography (CT), radiation exposure • Radiations, exposure to patients and personnel

	INTRODUCTION

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 
In hospitals in the United States, computed tomography (CT) accounts for just 13% of all diagnostic radiology procedures but is estimated to be responsible for more than 70% of the collective radiation dose delivered to patients (1,2). Recent high-speed multi–detector row CT technology creates more defined images in shorter times and has led to increased use of CT. With the introduction of new applications, the overall use of CT continues to grow inside and outside the hospital despite the fact that absorbed doses can be as much as 40% more than those associated with previous technology (3,4).

With growing use comes growing concern about risks associated with diagnostic CT. Effective doses with diagnostic CT have been shown to be similar to those received by Japanese survivors of the atomic bomb, who had a small but statistically significant increased risk of developing cancer as a result of the radiation (5). Findings in one heavily debated study (6) showed that the approximate number of deaths attributable to CT during 1 year in the United States was 700 for head examinations and 1,800 for abdominal examinations. Of these deaths, approximately 170 and 310, respectively, are attributable to pediatric CT examinations.

To date, according to a Medline search from 1966 to the present conducted by the first author, no researchers have examined practice patterns in regard to the information provided about the radiation dose and possible risks associated with diagnostic CT in patients who undergo such examinations. While a small survey of physicians in the United Kingdom showed that physicians have no real knowledge of the radiation dose that their patients receive (7), no data are available about the current knowledge level of patients, radiologists, or requesting physicians in the United States. Given growing concerns in the radiology community, this study aimed to determine the awareness level concerning radiation dose and possible risks associated with CT scans among patients, emergency department (ED) physicians, and radiologists.

	MATERIALS AND METHODS

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 
Participants
We designed three similar surveys that were administered to patients, ED physicians, and radiologists at our tertiary care center. The institutional human investigation committee approved the study protocol and surveys prior to the start of the study. The ED was used for patient enrollment to collect data from patients who required acquisition of a CT scan as part of their care. This setting was chosen because of the ease of patient enrollment and because a large proportion of CT scans at our institution are ordered by the ED physicians. The first author obtained oral informed consent from each patient for participation in the survey study. All ED physicians (attending and resident) were surveyed, not only those who cared directly for the study patients. All radiologists (attending and resident) who were involved in the reading of body CT scans throughout our institution, not only those who were involved with the study patient CT scans during the 2-week study period, were also surveyed.

Since nearly one-half of all CT scans acquired in the United States are in the abdomen or pelvis (2), we chose patients who were seen in the ED with mild to moderate pain in the abdomen, pelvis, or flank that necessitated acquisition of a diagnostic CT scan. Inclusion criteria were treatment in the adult ED (not pediatric ED) and fluency in English, as well as alertness, responsiveness, and ability to verbally communicate. All CT scans were ordered for clinically accepted and appropriate reasons by the ED physician (attending or resident) who was directly in charge of caring for the patient.

The survey was administered to consecutive patients seen during a 2-week period (June 13 through June 26, 2002, between 8 AM and 9 PM). By excluding patients with head injuries or serious trauma or those in serious discomfort, we avoided putting patients at risk unnecessarily by delaying urgent medical care for the sake of completing our survey. Prospective patients who met the inclusion criteria were approached by the first author after acquisition of the CT scan and were asked if they would like to participate. Oral informed consent was administered by the first author, with the option that he could provide at the time of discharge a written informational form that stated that the patient had participated in a survey study regarding awareness of radiation dose and that included the contact information for the human investigation committee if the patient had any further questions.

The survey was administered to each patient by the first author. If patients were able to read and write, they were handed the survey on a clipboard with a pen for them to complete. If patients preferred that the first author administer the survey orally, he read the instructions, each question, and all answer choices word for word. Patient answers were then recorded word for word by the first author. Patients were encouraged to answer to the best of their abilities, and no additional clarification or information was provided to any patient. Patient age and sex were recorded for demographic data.

To prevent study bias and physician self-education about the survey questions, the contents of the patient survey and the actual topic of the study remained unknown to ED physicians and radiologists. After the patient enrollment period ended, all resident and attending ED physicians and all resident and attending radiologists were surveyed within 1 week. During the 2-week patient study period and the 1-week physician study period, all ED physicians and radiologists were told only that they would be receiving a survey to complete and that they were not to discuss the contents with each other for 1 week because of the on-going nature of the study. The institutional review board waived informed consent for the ED physicians and radiologists. All ED physicians and radiologists were asked to complete their survey without consultation or research and to submit their surveys to the first author. All information that identified patients, ED physicians, and radiologists was removed before analysis.

Estimated Dose
For each patient CT scan, the cumulative dose length product (milligray per centimeter) was recorded from the scanner console (LightSpeed; GE Medical Systems, Milwaukee, Wis). Abdominopelvic CT was performed with 5-mm-thick sections and 7-mm intervals from the dome of the diaphragm through the symphysis pubis with oral contrast material and injection of 150 mL of intravenous contrast material at a rate of 3 mL/sec for 50 seconds. Abdominopelvic CT was performed with the following parameters: 120 kV, 280 mA, 1:1 pitch, and 24-second scan time, with 62 images produced. CT to evaluate flank pain was performed with 5-mm-thick sections and 2.5-mm intervals from the top of the kidneys through the base of the bladder without use of intravenous or oral contrast material. CT to evaluate flank pain was performed with the following parameters: 120 kV, 300 mA, 1:1 pitch, and 20-second scan time, with 143 images produced. The first author estimated the effective doses by multiplying cumulative dose length product values recorded from the scanner console by multipliers specific to each body part according to the method outlined by Jessen et al (8).

Patient Survey
Patients were asked whether or not anyone had outlined the risks and benefits of the CT scan to them (ie, provided informed consent to the patient for the procedure) before the scan was acquired, if radiation dose was mentioned, and if they believed that their lifetime risk for cancer was increased as a result of the CT scan. For these three questions, patients were allowed to answer only "yes" or "no." In addition, patients were asked to estimate the radiation dose for their CT scan compared with that for one chest radiograph—a dose that is well established in the literature. The radiation dose for one abdominal CT scan has been reported to be equivalent to that for 100–250 chest radiographs (1,2,9,10). To give respondents the ability to estimate a higher or lower dose, the comparison dose for a single chest radiograph was given a value of 100 arbitrary units.

ED Physician Survey
Requesting ED physicians (resident and attending) were asked whether or not they had outlined the risks and benefits of the CT scan for their patients, if they had mentioned radiation dose to them, and if they believed that their lifetime risk for cancer was increased as a result of the CT scan. ED physicians were asked the same question that the patients were asked about dose estimates for one abdominopelvic CT scan compared with one chest radiograph. Finally, the ED physician survey included an additional question about the number of years the respondent (attending physician or resident) had been in practice.

Radiologist Survey
While the ED physician survey included questions about whether "they" had outlined risks and mentioned dose, the resident and attending radiologists were asked if they believed that "someone" had outlined the risks and benefits of CT for patients before its performance, if "someone" had mentioned radiation dose to patients, and if they believed that a patient’s lifetime risk for cancer was increased as a result of the CT scan. The difference in wording between the radiologist and ED physician surveys is a result of the fact that ED physicians are in charge of direct patient care in our facility, while radiologists are not. Radiologists were asked the same question that the patients were asked about dose estimates for one abdominopelvic CT scan compared with one chest radiograph. Finally, the radiologist survey included a question about the number of years the respondent (radiologist or resident) had been in practice.

Statistical Analysis
The overall value for statistical significance was P < .05. For the patient data, the t test was used to determine if there was any statistically significant difference in the ages of male and female patients. The ² test of significance with exact tests of significance was used to determine differences in whether risk and benefits were outlined to patients on the basis of age and sex. The same test was used to examine differences in patient-perceived increased cancer risk as a result of the CT scan on the basis of age and sex. The Spearman correlation coefficient was used to examine the relationship between CT dose and patient age. To further explore possible differences on the basis of age and sex, the Mann-Whitney test was used to compare groups of patients on ordinal levels.

For both the ED physicians and radiologists, possible correlations between whether or not risks and benefits of the CT scan were explained to patients on the basis of years in practice and type of physician (ED physician or radiologist, attending or resident) were examined with the ² test of significance with exact tests of significance. The same analysis was used to determine if any significant difference existed between the number of years in practice and whether dose was mentioned to patients or whether there was a physician-perceived increased cancer risk from an abdominopelvic CT scan. The ² test of independence with exact tests of significance was used to examine the relationship between groups and whether or not they believed that there was increased cancer risk.

The Kruskal-Wallis test and ² test of independence with exact tests of significance were used to examine dose estimates for one CT scan compared with one chest radiograph in the three respondent groups. The deviations were examined on the basis of the adjusted standardized residuals. Possible correlations between years in practice and estimates of CT radiation dose were examined with the Spearman correlation coefficient. Any significant correlations were further examined with the Mann-Whitney test to compare two groups on ordinal levels.

	RESULTS

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 
Estimated Dose
The mean equipment-estimated CT doses were 13.1 mSv for an abdominopelvic CT scan and 9.6 mSv for a CT scan to evaluate flank pain. Since these doses were comparable to those for an abdominopelvic CT scan in the literature, we treated patients who underwent CT to evaluate flank pain and those who underwent abdominopelvic CT as the same for analytic purposes.

Patient Survey Results
Eighty-three patients who met the inclusion criteria were invited to participate in the study. Seven patients chose not to participate in the study because of either discomfort or inaccessibility to the investigator (eg, patient was sleeping). Seventy-six patients (49 female and 27 male patients; age range, 17–81 years; mean age, 43 years [mean age for female patients, 41 years; mean age for male patients, 45 years]) participated in the survey study. There was no statistically significant difference between the ages of male and female patients (t = –0.79, P = .43). All 76 patients completed the questions regarding whether or not anyone had outlined the risks and benefits of the CT scan for them before its acquisition, if radiation dose was mentioned and if they believed that their lifetime risk for cancer was increased as a result of the CT scan (Tables 1, 2).

There was a marginally significant difference between the type of physician and whether they outlined risks and benefits of a CT scan to their patients (²₁ = 4.11; Fisher exact significance, 0.062). Forty percent (six of 15) of ED attending physicians outlined risks and benefits to patients, whereas only 13% (four of 30) of residents did. The difference was not significant between resident and attending physicians and whether or not they mentioned radiation dose (²₁ = 0.00; Fisher exact significance, 1.00). There was also no significant difference between resident and attending physicians and whether they believed that there was increased cancer risk from one abdominopelvic CT scan (²₁ = 0.14; Fisher exact significance, 1.00).

All 45 ED physicians provided estimates of the radiation dose for one CT scan compared with one chest radiograph (Table 3). ED attending physicians were divided into two groups based on years in practice: less than 10 years versus 10 or more years. This cutoff was used since results with a cutoff of 5 years in practice would overlap substantially with the resident results. There was no significant relationship between ED physician years in practice and CT dose estimates (Spearman = 0.01, P = .94). With the Mann-Whitney comparison, there was also no statistically significant relationship between ED physician status as an attending or resident physician with CT dose estimates (Z = –0.04, P = .97).

Radiologist Survey Results
Forty-one radiologists (19 attending physicians, 22 residents) completed the survey. Their years in practice ranged from less than 1 to more than 31 years, with attending physicians averaging 12 and residents averaging 2 years. Results regarding whether or not they believed that someone outlined the risks and benefits of the abdominopelvic CT scan for patients before its acquisition, if they believed that somebody discussed radiation dose, and whether or not they believed that a patient’s lifetime risk for cancer was increased as a result of the CT scan can be found in Tables 1 and 2.

Radiologists were divided into two groups on the basis of years in practice: less than 10 years versus 10 years or more. This cutoff was used since results with a cutoff of 5 years in practice would overlap substantially with the resident results. There was no significant relationship between radiologist years in practice (²₁ = 1.50; Fisher exact significance, 0.50) or status as an attending or resident physician (²₁ = 2.29; Fisher exact significance, 0.20) with whether or not they believed that risks and benefits were outlined to patients. Because of the small number of positive respondents, no statistical analyses were conducted between the years in practice or status as attending or resident physician with whether or not radiologists believed that dose was mentioned to patients. There was also no significant relationship between radiologist years in practice (²₁ = 1.22; Fisher exact significance, 0.41) or status as an attending or resident physician (²₁ = 0.47; Fisher exact significance, 0.50) and whether or not radiologists believed that there was increased cancer risk from the abdominopelvic CT scan.

Thirty-nine radiologists provided a dose estimate for one CT scan compared with that for a single chest radiograph (Table 3). There was no significant relationship between radiologist years in practice and dose estimates (Spearman = 0.06, P = .70). With the Mann-Whitney comparison, there was also no statistically significant relationship between radiologist status as an attending or resident physician and dose estimates (Z = 0.84, P = .87).

Comparison of Three Respondent Groups
In a comparison of the three respondent groups by means of the ² test of independence, there was a significant relationship between the groups and perceived increased cancer risk from an abdominopelvic CT scan (²₂ = 41.45, P < .001). In an examination of the adjusted standardized residuals, radiologists were shown to be more likely than expected to perceive that there was increased cancer risk (Z = 6.4), while patients were less likely than expected to perceive that risk was increased (Z = –4.2). Forty-seven percent (18 of 38) of radiologists believed that there was increased cancer risk, whereas only 9% (four of 45) of ED physicians and 3% (two of 76) of patients believed that risk was increased.

Results of the Kruskal-Wallis test showed that patient CT dose estimates for their CT scan compared with one chest radiograph were significantly different (²₂ = 67.04, P < .001) from estimates of ED physicians and radiologists. To further analyze this finding, we applied the ² test of independence with exact tests of significance on the basis of the categoric classifications shown in Table 3. We found a statistically significant relationship between the three respondent groups and CT dose estimates (²₈ = 43.42, P < .001). We then examined where the deviations were by looking at the adjusted standardized residuals between what was observed and what was expected.

Patients were significantly more likely than expected to estimate the dose for one CT scan as less than or equal to that for a chest radiograph (Z = 3.70, P < .05). Twenty-eight percent (19 of 67) of patients believed that the dose for their CT scan was less than or equal to that for a chest radiograph in comparison to only 7% (three of 45) of ED physicians and 5% (two of 39) of radiologists. Patients were also significantly more likely to greatly underestimate the dose for their CT scan (estimated dose, no more than 10 times the dose for a chest radiograph) (Z = 2.30, P < .05). Sixty-four percent (43 of 67) of patients greatly underestimated the dose for their CT scan in comparison to 44% (20 of 45) of ED physicians and 56% (22 of 39) of radiologists.

No statistically significant difference was found between the dose estimates of radiologists and ED physicians. However, ED physicians were shown to be less likely to greatly underestimate CT dose (estimated dose, no more than 10 times the dose for a chest radiograph) (Z = –2.2), more likely to slightly underestimate CT dose (estimated dose, greater than 10 times but less than 100 times the dose for a chest radiograph) (Z = 2.5), and more likely to accurately estimate CT dose (Z = 3.3) in comparison to the other two study groups.

	DISCUSSION

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 
Nearly all of our sample of patients seen at the ED with mild to moderate pain in the abdomen, pelvis, or flank were not provided information regarding the radiation dose and possible risks associated with diagnostic CT scans before their acquisition. Seventy-eight percent (35 of 45) of ED physicians stated that they did not outline the risks and benefits of the CT scan to patients, and 93% (71 of 76) of patients reported that they did not receive such information. ED attending physicians were only slightly more likely to outline the risks and benefits than were ED residents. Nearly all of the patients reported not being told about the radiation dose, and only 9% (four of 45) of ED physicians reported that they mentioned the dose to patients.

Just as participating patients were uninformed about radiation dose, surveyed ED physicians and radiologists were also largely uninformed about radiation dose. Patients, ED physicians, and radiologists were all, for the most part, unable to provide an accurate estimate of dose for one CT scan compared with that for a chest radiograph. Although a greater percentage of ED physicians (22%) were able to provide an accurate estimate of CT dose than were the radiologists (15%), the difference was not statistically significant.

Most of the patients and requesting ED physicians surveyed did not perceive a possible increased cancer risk associated with a diagnostic CT scan, while nearly half of the radiologists did. Analyses by means of linear extrapolation of atomic bomb data that show increased cancer risk from CT have been heavily debated (11). Whether or not increased cancer risk exists, the disproportion in opinions between radiologists and nonradiologists suggests that current information regarding possible radiation-related risks is not being disseminated from the radiology community to either requesting ED physicians or patients.

Although the results of this study show that the surveyed patients were poorly informed about radiation dose and possible risks attributed to their CT scans, it should be stressed that they were told of other risks, including possible adverse effects of intravenous contrast material. The survey questions were focused on issues surrounding radiation dose and should not be mistaken as indicating a complete lack of information regarding CT scans.

Patients were enrolled from the ED because the majority of imaging studies are ordered for patients admitted from there. Although enrollment of patients from an outpatient elective screening center would have been ideal, such a study design presented the ethical dilemma of exposing patients to unnecessary CT radiation. In order to not disturb the flow of patient care, patients in only mild to moderate discomfort were invited to participate while they were waiting for transportation back to the main ED floor from the radiology department. While the data can likely be generalized to include similar patient populations in similar ED settings across the country, they most likely cannot be generalized to outpatient settings such as elective screening centers.

Limitations of this study include the small sample size and the fact that all patients were enrolled from the ED of one medical center. A few ED physicians and radiologists did not like the affirmative "yes" or "no" responses without a "sometimes" option for the questions concerning the outlining of risks and benefits and the mentioning of dose. Thus, we investigators assumed that a yes response meant that ED physicians always informed patients about radiation risks. Another limitation was the use of open-ended rather than multiple-choice answers for the survey questions about radiation dose estimates. In addition, several respondents were confused about the comparison scenario and did not provide answers. Finally, the radiologist survey examined the belief that somebody else had outlined the risks and benefits to the patients, while the ED physician survey examined whether they had outlined the risks and benefits to patients. Thus, although the questions were similar, the radiologist and ED physician surveys were not identical, which led to imperfect statistical comparisons between the two groups.

Given the current debate about the possible increased cancer risk associated with diagnostic CT scans, we believe that it is important that the radiology community make current information regarding CT radiation dose more widely available. In particular, ED physicians, who order such studies, should be educated about the magnitude of diagnostic CT radiation dose and possible long-term consequences. While our medical center has not yet made amendments to our educational programs, the education of referring ED physicians and patients regarding CT dose was recommended at a recent national conference on CT dose reduction (12).

We also argue that current information regarding radiation dose and possible associated risks should be made available to the general public to help ensure that all parties, patients and healthcare providers, are aware of the information necessary to more accurately weigh the risks and benefits associated with diagnostic CT scans (13,14). While we believe that this information should be presented to all patients, it obviously cannot be communicated to the subsets of patients in need of emergent diagnostic CT and those who are unable to provide informed consent. Yet, this information should at least be distributed to patients who are able to take the time and consider the information in light of their healthcare needs. Dissemination of this material will be crucial to maintain the public trust in the radiology community as responsible caregivers (15).

In light of the media storm that befell the radiology community regarding pediatric CT scans and possible increased lifetime cancer risk, full disclosure of the current knowledge level about radiation dose and possible risks should be distributed in appropriate language and in a manner that does not cause public panic. Two possible methods include the posting of clear announcements with associated CT radiation doses and reference ranges in CT department waiting areas and the availability of informational pamphlets in outpatient waiting rooms. Large national radiology associations are probably best suited for assuming the leadership for production of such educational material without causing unnecessary public fear (16).

	ACKNOWLEDGMENTS

 
The authors thank Robert Lange, PhD (Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Conn), and Trace Kershaw, PhD (Division of Chronic Disease Epidemiology, Yale School of Public Health, New Haven, Conn), for lending their respective knowledge and expertise to this study.

	FOOTNOTES

 
Abbreviation: ED = emergency department

Author contributions: Guarantors of integrity of entire study, C.I.L., H.P.F.; study concepts and design, all authors; literature research, C.I.L.; clinical studies, C.I.L.; data acquisition, C.I.L., A.H.H., E.P.M.; data analysis/interpretation, all authors; manuscript preparation, definition of intellectual content, editing, revision/review, and final version approval, all authors

	REFERENCES

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION REFERENCES

 

1. Dixon AK, Goldstone KE. Abdominal CT and the Euratom Directive. Eur Radiol 2002; 12:1567-1570.[CrossRef][Medline]
2. Mettler FA, Jr, Wiest PW, Locken JA, Kelsey CA. CT scanning: patterns of use and dose. J Radiol Prot 2000; 20:353-359.[CrossRef][Medline]
3. Golding SJ, Shrimpton PC. Commentary. Radiation dose in CT: are we meeting the challenge? Br J Radiol 2002; 75:1-4.
4. Haaga JR. Radiation dose management: weighing risk versus benefit. AJR Am J Roentgenol 2001; 177:289-291.[Free Full Text]
5. Pierce DA, Preston DL. Radiation-related cancer risks at low doses among atomic bomb survivors. Radiat Res 2000; 154:178-186.[Medline]
6. Brenner D, Elliston C, Hall E, Berdon W. Estimated risks of radiation-induced fatal cancer from pediatric CT. AJR Am J Roentgenol 2001; 176:289-296.[Abstract/Free Full Text]
7. Gower-Thomas K, Lewis MH, Shiralkar S, Snow M, Galland RB, Rennie A. Doctors’ knowledge of radiation exposures is deficient (letter). BMJ 2002; 324:919.[Free Full Text]
8. Jessen KA, Shrimpton PC, Geleijns J, Panzer W, Tosi G. Dosimetry for optimisation of patient protection in computed tomography. Appl Radiat Isot 1999; 50:165-172.[CrossRef][Medline]
9. Dixon AK, Dendy P. Spiral CT: how much does radiation dose matter? Lancet 1998; 352:1082-1083.[CrossRef][Medline]
10. Trott KR. Radiation risks from imaging of intestinal and abdominal inflammation. Scand J Gastroenterol Suppl 1994; 203:43-47.[Medline]
11. Donnelly LF, Frush DP. Fallout from recent articles on radiation dose and pediatric CT. Pediatr Radiol 2001; 31:388; discussion 389-391.
12. Linton OW, Mettler FA, Jr. National conference on dose reduction in CT, with an emphasis on pediatric patients. AJR Am J Roentgenol 2003; 181:321-329.[Free Full Text]
13. Lewis C. Full-body CT scans: what you need to know. FDA Consum 2001; 35:10.
14. Thomas RH, Lindell B. In radiological protection, the protection quantities should be expressed in terms of measurable physical quantities. Radiat Prot Dosimetry 2001; 94:287-292.[Abstract]
15. Nickoloff E. Current adult and pediatric CT doses. Pediatr Radiol 2002; 32:250-260.[CrossRef][Medline]
16. Earnest F, Swensen SJ, Zink FE. Respecting patient autonomy: screening at CT and informed consent. Radiology 2003; 226:633-634.[Free Full Text]

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				D. Brenner and W. Huda EFFECTIVE DOSE: A USEFUL CONCEPT IN DIAGNOSTIC RADIOLOGY Radiat Prot Dosimetry, March 28, 2008; (2008) ncn056v1. [Full Text] [PDF]

				B. P. Wood CT Scans and Radiation Exposure AAP Grand Rounds, March 1, 2008; 19(3): 28 - 29. [Full Text] [PDF]

				T. Kubo, P.-J. P. Lin, W. Stiller, M. Takahashi, H.-U. Kauczor, Y. Ohno, and H. Hatabu Radiation Dose Reduction in Chest CT: A Review Am. J. Roentgenol., February 1, 2008; 190(2): 335 - 343. [Abstract] [Full Text] [PDF]

				D. J. Brenner and E. J. Hall Computed Tomography -- An Increasing Source of Radiation Exposure N. Engl. J. Med., November 29, 2007; 357(22): 2277 - 2284. [Full Text] [PDF]

				M. Voress The Increasing Use of CT and Its Risks Radiol. Technol., November 1, 2007; 79(2): 186 - 190. [Full Text] [PDF]

				S. Ulmer, E. Schulz, B. Moeller, U.R. Krause, A. Nabavi, H.M. Mehdorn, and O. Jansen Radiation Dose of the Lens in Trans-sphenoidal Pituitary Surgery: Pros and Cons of a Conventional Setup Using Fluoroscopic Guidance and CT-Based Neuronavigation AJNR Am. J. Neuroradiol., September 1, 2007; 28(8): 1559 - 1564. [Abstract] [Full Text] [PDF]

				J. E. COLANG, J. B. KILLION, and E. VANO Patient Dose From CT: A Literature Review Radiol. Technol., September 1, 2007; 79(1): 17 - 26. [Abstract] [Full Text] [PDF]

				A. S. Brody, D. P. Frush, W. Huda, R. L. Brent, and and the Section on Radiology Radiation Risk to Children From Computed Tomography Pediatrics, September 1, 2007; 120(3): 677 - 682. [Abstract] [Full Text] [PDF]

				D. B. Larson, S. B. Rader, H. P. Forman, and L. Z. Fenton Informing Parents About CT Radiation Exposure in Children: It's OK to Tell Them Am. J. Roentgenol., August 1, 2007; 189(2): 271 - 275. [Abstract] [Full Text] [PDF]

				E L Nickoloff and P O Alderson A comparative study of thoracic radiation doses from 64-slice cardiac CT Br. J. Radiol., July 1, 2007; 80(955): 537 - 544. [Abstract] [Full Text] [PDF]

				A. M. Groves, S. J. Yates, T. Win, I. Kayani, F. A. Gallagher, R. Syed, J. Bomanji, and P. J. Ell CT Pulmonary Angiography versus Ventilation-Perfusion Scintigraphy in Pregnancy: Implications from a UK Survey of Doctors' Knowledge of Radiation Exposure Radiology, September 1, 2006; 240(3): 765 - 770. [Abstract] [Full Text] [PDF]

				C. I. Lee, H. V. Flaster, A. H. Haims, E. P. Monico, and H. P. Forman Diagnostic CT scans: institutional informed consent guidelines and practices at academic medical centers. Am. J. Roentgenol., August 1, 2006; 187(2): 282 - 287. [Abstract] [Full Text] [PDF]

				D. K. Yousefzadeh, M. B. Ward, and C. Reft Internal Barium Shielding to Minimize Fetal Irradiation in Spiral Chest CT: A Phantom Simulation Experiment. Radiology, June 1, 2006; 239(3): 751 - 758. [Abstract] [Full Text] [PDF]

				L. M. Hurwitz, T. Yoshizumi, R. E. Reiman, P. C. Goodman, E. K. Paulson, D. P. Frush, G. Toncheva, G. Nguyen, and L. Barnes Radiation Dose to the Fetus from Body MDCT During Early Gestation. Am. J. Roentgenol., March 1, 2006; 186(3): 871 - 876. [Abstract] [Full Text] [PDF]

				C. M. Cavett Report of a Clinical Practice Guideline for Appendicitis AAP Grand Rounds, April 1, 2005; 13(4): 43 - 44. [Full Text] [PDF]

				B. P. Wood Lack of Awareness of CT Scan Radiation Dose AAP Grand Rounds, December 1, 2004; 12(6): 65 - 66. [Full Text] [PDF]

				E. N. C. Milne and D. J. Brenner Breast: The Forgotten Organ * Dr Brenner responds: Radiology, December 1, 2004; 233(3): 937 - 938. [Full Text] [PDF]

				D. S. Katz, M. Jain, M. J. Lane, E. M. Meiner, S. Bhalla, C. O. Menias, and C. M. Rucker Invited Commentary * Authors' Response RadioGraphics, October 1, 2004; 24(suppl_1): S28 - S33. [Full Text] [PDF]

				M. Edmonds Review: inflammatory response variables, descriptors of peritoneal irritation, and migration of pain are most discriminatory of appendicitis Evid. Based Med., July 1, 2004; 9(4): 120 - 120. [Full Text] [PDF]

				M. Edmonds Review: the use of computed tomographic scanning has high sensitivity, specificity, and accuracy for diagnosing acute appendicitis in adults Evid. Based Med., July 1, 2004; 9(4): 121 - 121. [Full Text] [PDF]

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