Scott W. Atlas

All Publications

• Fact-Based Health Care Reform Atlas, S. W. The American Interest. 2017
• Exposure to Ionizing Radiation and Estimate of Secondary Cancers in the Era of High-Speed CT Scanning: Projections From the Medicare Population JOURNAL OF THE AMERICAN COLLEGE OF RADIOLOGY Meer, A. B., Basu, P. A., Baker, L. C., Atlas, S. W. 2012; 9 (4): 245-250

  Abstract

  The aims of this study were to analyze the distribution and amount of ionizing radiation delivered by CT scans in the modern era of high-speed CT and to estimate cancer risk in the elderly, the patient group most frequently imaged using CT scanning.A retrospective cohort study was conducted using Medicare claims spanning 8 years (1998-2005) to assess CT use. The data were analyzed in two 4-year cohorts, 1998 to 2001 (n = 5,267,230) and 2002 to 2005 (n = 5,555,345). The number and types of CT scans each patient received over the 4-year periods were analyzed to determine the percentage of patients exposed to threshold radiation of 50 to 100 mSv (defined as low) and >100 mSv (defined as high). The National Research Council's Biological Effects of Ionizing Radiation VII models were used to estimate the number of radiation-induced cancers.CT scans of the head were the most common examinations in both Medicare cohorts, but abdominal imaging delivered the greatest proportion (43% in the first cohort and 40% in the second cohort) of radiation. In the 1998 to 2001 cohort, 42% of Medicare patients underwent CT scans, with 2.2% and 0.5% receiving radiation doses in the low and high ranges, respectively. In the 2002 to 2005 cohort, 50% of Medicare patients received CT scans, with 4.2% and 1.2% receiving doses in the low and high ranges. In the two populations, 1,659 (0.03%) and 2,185 (0.04%) cancers related to ionizing radiation were estimated, respectively.Although radiation doses have been increasing along with the increasing reliance on CT scans for diagnosis and therapy, using conservative estimates with worst-case scenario methodology, the authors found that the risk for secondary cancers is low in older adults, the group subjected to the most frequent CT scanning. Trends showing increasing use, however, underscore the importance of monitoring CT utilization and its consequences.

  View details for DOI 10.1016/j.jacr.2011.12.007

  View details for Web of Science ID 000305449600010

  View details for PubMedID 22469374

• The Worst Study Ever? COMMENTARY Atlas, S. W. 2011; 131 (4): 27-32

  View details for Web of Science ID 000288586600008

• Assessing Cost-Effectiveness And Value As Imaging Grows: The Case Of Carotid Artery CT HEALTH AFFAIRS Baker, L. C., Afendulis, C. C., Atlas, S. W. 2010; 29 (12): 2260-2267

  Abstract

  Computed tomographic (CT) angiography is an imaging test that is safer and less expensive than an older test in diagnosing narrowing of the carotid arteries-the most common cause of stroke in US adults. Our examination of Medicare data between 2001 and 2005 found that about 20 percent of the time this test was used, it substituted for the older test. The majority of new use, however, constituted "incremental" use, in cases where patients previously would not have received any test. We found no evidence that the growth in CT angiography led to more patients' being treated for carotid artery disease. The value of the test as a substitute for the older procedure may be enough to still justify expanding use. Tracking the uses of emerging technologies to encourage efficient use is essential, but it can be challenging in cases where new tools have multiple uses and information is incomplete.

  View details for DOI 10.1377/hlthaff.2010.0046

  View details for Web of Science ID 000285016000017

  View details for PubMedID 21134928

• HEALTH INSURANCE AND CATASTROPHIC ILLNESS: A REPORT ON THE NEW COOPERATIVE MEDICAL SYSTEM IN RURAL CHINA HEALTH ECONOMICS Yi, H., Zhang, L., Singer, K., Rozelle, S., Atlas, S. 2009; 18: S119-S127

  Abstract

  The overall goal of the paper is to understand the progress of the design and implementation of China's New Cooperative Medical System (NCMS) program between 2004 (the second year of the program) and 2007. In the paper we seek to assess some of the strengths and weaknesses of the program using a panel of national-representative, household survey data that were collected in 2005 and early 2008. According to our data, we confirm the recent reports by the Ministry of Health that there have been substantial improvements to the NCMS program in terms of coverage and participation. We also show that rural individuals also perceive an improvement in service by 2007. While the progress of the NCMS program is clear, there are still weaknesses. Most importantly, the program clearly does not meet one of its key goals of providing insurance against catastrophic illnesses. On average, individuals that required inpatient treatment in 2007 were reimbursed for 15% of their expenditures. Although this is higher than in 2004, on average, as the severity of the illness (in terms of expenditures on health care) rose, the real reimbursement rate (reimbursement amount/total expenditure on medical care) fell. The real reimbursement rate for illnesses that required expenditures between 4000 and 10,000 yuan (over 10,000 yuan) was only 11% (8%). Our analysis shows that one of the limiting factors is constrained funding.

  View details for DOI 10.1002/hec.1510

  View details for Web of Science ID 000267744300010

  View details for PubMedID 19551747

• Expanded Use Of Imaging Technology And The Challenge of Measuring Value HEALTH AFFAIRS Baker, L. C., Atlas, S. W., Afendulis, C. C. 2008; 27 (6): 1467-1478

  Abstract

  The availability of computed tomography (CT) and magnetic resonance imaging (MRI) scanning has grown rapidly, but the value of increased availability is not clear. We document the relationship between CT and MRI availability and use, and we consider potentially important sources of benefits. We discuss key questions that need to be addressed if value is to be well understood. In an example we study, expanded imaging may be valuable because it provides quicker access to more precise diagnostic information, although evidence for improved health outcomes is limited. This may be a common situation; thus, a particularly important question is how non-health-outcome benefits of imaging can be quantified.

  View details for DOI 10.1377/hlthaff.27.6.1467

  View details for Web of Science ID 000260769300003

  View details for PubMedID 18997202

• Embracing subspecialization: the key to the survival of radiology. Journal of the American College of Radiology Atlas, S. W. 2007; 4 (11): 752-753

  View details for PubMedID 17964496

• Advertising, patient decision making, and self-referral for computed tomographic and magnetic resonance imaging ARCHIVES OF INTERNAL MEDICINE Illes, J., Kann, D., Karetsky, K., Letourneau, P., Raffin, T. A., Schraedley-Desmond, P., Koenig, B. A., Atlas, S. W. 2004; 164 (22): 2415-2419

  Abstract

  Self-referred imaging is one of the latest health care services to be marketed directly to consumers. Most aspects of these services are unregulated, and little is known about the messages in advertising used to attract potential consumers. We conducted a detailed analysis of print advertisements and informational brochures for self-referred imaging with respect to themes, content, accuracy, and emotional valence.Forty print advertisements from US newspapers around the country and 20 informational brochures were analyzed by 2 independent raters according to 7 major themes: health care technology; emotion, empowerment, and assurance; incentives; limited supporting evidence; popular appeal; statistics; and images. The Fisher exact test was used to identify significant differences in information content.Both the advertisements and the brochures emphasized health care and technology information and provided assurances of good health and incentives to self-refer. These materials also encouraged consumers to seek further information from company resources; virtually none referred to noncomplying sources of information or to the risks of having a scan. Images of people commonly portrayed European Americans. We found statistical differences between newspaper advertisements and mailed brochures for references to "prevalence of disease" (P<.001), "death" (P<.003), and "radiation" (P<.001). Statements lacking clear scientific evidence were identified in 38% of the advertisements (n = 15) and 25% of the brochures (n = 5).Direct-to-consumer marketing of self-referred imaging services, in both print advertisements and informational brochures, fails to provide prospective consumers with comprehensive balanced information vital to informed autonomous decision making. Professional guidelines and oversight for advertising and promotion of these services are needed.

  View details for Web of Science ID 000225701900003

  View details for PubMedID 15596630

• Relationship between HMO market share and the diffusion and use of advanced MRI technologies. Journal of the American College of Radiology Baker, L. C., Atlas, S. W. 2004; 1 (7): 478-487

  Abstract

  Financial incentives associated with managed care may shift incentives associated with the adoption of new medical technologies. This study examined whether managed-care activity was associated with the adoption rate of magnetic resonance imaging (MRI) equipment during the 1990s.Data from three nationwide "censuses" of MRI sites conducted in 1993, 1997, and 1999 were used. The number of MRI sites and magnets; magnet field strength; MRI procedures; the use of contrast media; and the presence of power injectors, echoplanar imaging, cardiac MRI, and interventional MRI were measured in each of 322 metropolitan statistical areas each year. Regression analysis was used to assess the relationship between area MRI availability and overall area health maintenance organization (HMO) market share, controlling for potential confounders.Areas with higher HMO activity had markedly lower adoption and use of MRI. By 1999, high-HMO areas had about 40% fewer MRI scanners per 100,000 people than low-HMO areas (1.02 vs. 1.73, P < .01). High-HMO areas had fewer 1.5-T scanners than low areas in all 3 years and tended to use contrast media less often in 1993 and 1997 (all P < .01). There were statistically insignificant trends toward less availability of echoplanar imaging, cardiac MRI, and interventional MRI in high-HMO areas.The fact that managed care is associated with the slower adoption of MRI and less availability of some of the most advanced MRI equipment suggests the need for attention to the potential for managed care to have important effects on the quality of care and health care spending by influencing technology growth.

  View details for PubMedID 17411636

• Ethical consideration of incidental findings on adult brain MRI in research NEUROLOGY Illes, J., Rosen, A. C., Huang, L., Goldstein, R. A., Raffin, T. A., Swan, G., Atlas, S. W. 2004; 62 (6): 888-890

  Abstract

  To characterize the frequency and severity of incidental findings in brain MRIs of young and older adult research volunteers, and to provide an evaluation of the ethical challenges posed by the detection of such findings.The authors reviewed 151 research MRI scans obtained retrospectively from subjects recruited to studies as healthy volunteers. Incidental findings were classified into four categories: no referral, routine, urgent, or immediate referral. p Values for significance were computed from chi(2) tests of contingency.Of 151 studies, the authors found an overall occurrence of incidental findings having required referral of 6.6%. By age, there were more findings in the older cohort (aged >60 years) than in the younger cohort (p < 0.05) and in more men than women in the older cohort (p < 0.001). Three of four (75%) findings in the younger cohort were classified in the urgent referral category; 100% of the findings in the older cohort were classified as routine (p < 0.05).The significant presence but different characteristics of incidental findings in young and older subjects presumed to be neurologically healthy suggest that standards of practice are needed to guide investigators in managing and communicating their discovery.

  View details for Web of Science ID 000220365300010

  View details for PubMedID 15037687

  View details for PubMedCentralID PMC1506751

• Magnetic resonance image-guided proteomics of human glioblastoma multiforme JOURNAL OF MAGNETIC RESONANCE IMAGING Hobbs, S. K., Shi, G. Y., Homer, R., Harsh, G., Atlas, S. W., Bednarski, M. D. 2003; 18 (5): 530-536

  Abstract

  To investigate the correlation between gadolinium contrast-enhancement patterns on T1-weighted magnetic resonance (MR) images and spatial changes in protein expression profiles in human glioblastoma multiforme (GBM) and the use of imaging as a noninvasive technique to evaluate the heterogeneity of solid tumors prior to microarray analysis.Four patients with MR images and confirmed diagnosis of GBM were enrolled in the study. Intraoperative stereotaxy was used in conjunction with MR images to identify contrast-enhanced (CE) and nonenhanced (NE) regions of the tumor during surgical resection. Total protein was extracted from resected tumor samples using standard techniques and subjected to proteomic analysis using surface enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF-MS).We found that protein profiles from CE and NE regions within a given tumor have qualitative and semiquantitative proteomic pattern differences, suggesting an altered gene expression profile that correlates with detectable tissue imaging parameters. We also found that CE regions within the same tumor exhibited distinct differences in protein expression profiles, despite similar histological features. In addition, there were marked similarities in the proteomic patterns among the NE regions across all patients, while the CE regions were distinct, suggesting that the CE regions have complex protein profiles unique to individuals.The results demonstrate that major differences in protein expression patterns within a tumor can be correlated to radiographic findings. Image-guided proteomics holds promise for characterizing tissue prior to microarray analysis designed to identify specific diagnostic markers and therapeutic targets within solid tumors.

  View details for DOI 10.1002/jmri.10395

  View details for Web of Science ID 000186295300002

  View details for PubMedID 14579395

• Self-referred whole-body CT imaging: Current implications for health care consumers RADIOLOGY Illes, J., Fan, E., Koenig, B. A., Raffin, T. A., Kann, D., Atlas, S. W. 2003; 228 (2): 346-351

  Abstract

  To conduct an empirical analysis of self-referred whole-body computed tomography (CT) and develop a profile of the geographic and demographic distribution of centers, types of services and modalities, costs, and procedures for reporting results.An analysis was conducted of Web sites for imaging centers accepting self-referred patients identified by two widely used Internet search engines with large indexes. These Web sites were analyzed for geographic location, type of screening center, services, costs, and procedures for managing imaging results. Demographic data were extrapolated for analysis on the basis of center location. Descriptive statistics, such as frequencies, means, SDs, ranges, and CIs, were generated to describe the characteristics of the samples. Data were compared with national norms by using a distribution-free method for calculating a 95% CI (P <.05) for the median.Eighty-eight centers identified with the search methods were widely distributed across the United States, with a concentration on both coasts. Demographic analysis further situated them in areas of the country characterized by a population that consisted largely of European Americans (P <.05) and individuals of higher education (P <.05) and socioeconomic status (P <.05). Forty-seven centers offered whole-body screening; heart and lung examinations were most frequently offered. Procedures for reporting results were highly variable.The geographic distribution of the centers suggests target populations of educated health-conscious consumers who can assume high out-of-pocket costs. Guidelines developed from within the profession and further research are needed to ensure that benefits of these services outweigh risks to individuals and the health care system.

  View details for DOI 10.1148/radiol.2282021083

  View details for Web of Science ID 000184381100010

  View details for PubMedID 12893896