Nancy Obuchowski, PhD
Vice Chair
Joint Appointment, Diagnostic Radiology, Imaging Institute
Email: [email protected]
Location: Cleveland Clinic Main Campus
Research
Dr. Obuchowski works with radiologists to develop and test new ways to image patients or to find new features on images that predict patients’ well-being. Conventional imaging methods are sometimes not accurate enough, take too much time, are invasive, or too costly. Dr. Obuchowski plans research studies to test new imaging methods, then she analyzes the results and determines how the new methods performed. Dr. Obuchowski has developed methods for designing and testing imaging tests and biomarkers.
Biography
Nancy A. Obuchowski, PhD, is Vice Chair of the Department of Quantitative Health Sciences and Staff researcher in the Department of Diagnostic Radiology, located on the main campus of Cleveland Clinic. She was appointed in 1991 and previously served as an associate staff member in the Department of Biostatistics and Epidemiology and Radiology from 1997 – 2003. She is a fellow of the American Statistical Association, and was the Anne and Donald Herbert Distinguished Lecturer in Modern Statistical Modeling in 2021.
Dr. Obuchowski serves on the steering committee for the Quantitative Imaging Biomarker Alliance and the Clinical Imaging Steering Committee for the National Cancer Institute; she is chairman of the metrology committee for multi-parametric imaging.
She has authored or co-authored over 200 journal articles as well as various selected publications, books and book chapters, including "Statistical Methods in Diagnostic Medicine" (Zhou XH, Obuchowski NA, McClish DL.; Wiley and Sons, Inc., New York, 2002 and 2011) and “Handbook for Clinical Trials of Imaging and Image-Guided Interventions” (Obuchowski NA and Gazelle GS; Wiley and Sons, Inc, New York, 2016.
Education & Professional Highlights
Appointed
1991
Graduate School - University of Pittsburgh
Pittsburgh, PA USA
1991, PhD
Graduate School - University of Pittsburgh
Pittsburgh, PA USA
1987
Undergraduate - University of New Hampshire
1984
Research
Dr. Obuchowski’s primary focus is collaborative and methodologic research into the assessment of screening and diagnostic tests. She has been analyzing imaging data (diagnostic, screening, and quantitative biomarker data) and developing new study designs and methods of analysis for over 25 years. Dr. Obuchowski has authored or co-authored 200 journal papers in the imaging literature, as well as three books. She has served as co-director of metrology workshops on quantitative imaging biomarkers, editor of a special series on quantitative imaging for Statistical Methods in Medical Research, and co-director of RSNA’s clinical trials methodology workshops; she is on the steering committee of the NCI Clinical Imaging network and the Quantitative Imaging Biomarker Alliance, as well as numerous Data Safety and Monitoring Committees. Dr. Obuchowski is a fellow of the American Statistical Association.
Dr. Obuchowski’s PhD dissertation addressed the analysis of a common study design in radiology – a multi-reader Receiver Operating Characteristic (ROC) study- where the goal is to compare the accuracy of two or more diagnostic tests. The tests require interpretation by a trained reader, and, naturally, readers have different cognitive and visual abilities. She developed a method of comparing the accuracies of tests, while incorporating the variability of readers and the correlations in the data introduced by the study design; she also addressed how to compute sample size for these studies. These methods are used in many clinical trials for comparing imaging modalities, as well as assessing the effect of computer-aided detection and artificial intelligence (AI) algorithms in medical imaging.
At the Cleveland Clinic Dr. Obuchowski see lots of studies with clustered data - two breasts, four thyroid glands, multiple lesions in the same patient. Multiple observations from the same patient cannot be treated as independent because of the correlation that exists between the observations from the same patient. Dr. Obuchowski extended a simple idea for clustered binary data to single-reader and multi-reader ROC analysis. This method is used widely in radiology research.
New, less invasive or less expensive tests are constantly being developed to replace conventional imaging methods. For these situations, since the new test is less risky, it can have a little less accuracy than the old test and still be more efficacious. Dr. Obuchowski developed a statistical method to test for equivalence, using different criteria for equivalence. Similarly, she has developed new statistical methods that test for interchangeability of new tests with conventional tests
Sometimes the diagnostic test needs to do more than detect a disease - sometimes correctly locating the lesion(s) is critical to the management of the patient. Dr. Obuchowski developed a method for analyzing data that takes both detection and localization of multiple lesions into account. The new statistical method accounts for the correlations between multiple lesions and between multiple false detections, whereas other methods assumed independence. Dr. Obuchowski has worked on extending ROC analysis to the detection of multiple different diseases, as well as staging disease.
Most recently, Dr. Obuchowski has focused on statistical methods for assessing the technical performance of quantitative imaging biomarkers (QIBs). QIBs are disease characteristics that can be automatically derived from a patient’s medical image. These biomarkers are useful for assessing changes in patients’ disease, both in clinical practice and clinical trials. Dr. Obuchowski has worked with the Quantitative Imaging Biomarker Alliance to develop appropriate metrics and study designs to assess these powerful new endpoints.
Our Team
Selected Publications
View publications for Nancy Obuchowski, PhD
(Disclaimer: This search is powered by PubMed, a service of the U.S. National Library of Medicine. PubMed is a third-party website with no affiliation with Cleveland Clinic.)
Jones MH; MOON Knee Group, Spindler KP, Andrish JT, Cox CL, Dunn WR, Duryea J, Duong CL, Flanigan DC, Fleming BC, Huston LJ, Kaeding CC, Matava MJ, Obuchowski NA, Oksendahl HL, Parker RD, Scaramuzza EA, Smith MV, Winalski CS, Wright RW, Reinke EK. Differences in the lateral compartment joint space after anterior cruciate ligament reconstruction: data from the MOON onsite cohort. Am J Sports Med. 2018 Jan 1.
Alaia EF, Benedick A, Obuchowski NA, Polster JM, Beltran LS, Schils J, Garwood E, Burke CJ, Chang IJ, Gyftopoulos S, Subhas N. Comparison of a fast 5-min knee MRI protocol with a standard knee MRI protocol: a multi-institutional multi-reader study. Skeletal Radiol. 2018; 47:107-116.
Yokoo T, Serai SD, Pirasteh A, Bashir MR, Hamilton G, Hernando D, Hu HH, Hetterich H, Kühn JP, Kukuk GM, Loomba R, Middleton MS, Obuchowski NA, Song JS, Tang A, Wu X, Reeder SB, Sirlin CB; RSNA-QIBA PDFF Biomarker Committee. Linearity, bias, and precision of hepatic proton density fat fraction measurements by using MR imaging: a meta-analysis. Radiology. 2018; 286: 486-498.
Sheahan M, Ma X, Paik D, Obuchowski NA, St Pierre S, Newman WP 3rd, Rae G, Perlman ES, Rosol M, Keith JC Jr, Buckler AJ. Atherosclerotic plaque tissue: noninvasive quantitative assessment of characteristics with software-aided measurements from conventional CT angiography. Radiology 2018; 286: 622-631.
Obuchowski NA, Bullen JA. Receiver Operating Characteristic (ROC) curves: review of methods with applications in diagnostic medicine. Physics in Medicine and Biology 2018: 63:
Obuchowski NA, Mozley DP, Matthews D, Buckler A, Bullen J, and Jackson E. Statistical Considerations for Planning Clinical Trials with Quantitative Imaging Biomarkers. JNCI; 2018 Dec 31. Epub 2018.
Shukla-Dave A, Obuchowski NA, Chenevert TL, et al. Quantitative imaging biomarkers alliance (QIBA) recommendations for improved precision of DWI and DCE‐MRI derived biomarkers in multicenter oncology trials. J Magn Reson Imaging 2018 Nov 19. Epub 2018.
Kwon DH, Obuchowski NA, Marwick TH, Menon V, Griffin B, Flamm SD, Hachamovitch R. Jeopardized myocardium defined by late gadolinium enhancement magnetic resonance imaging predicts survival in patients with ischemic cardiomyopathy: impact of revascularization. J Magn Reson Imaging 2018 Nov 19. Epub 2018.
Wunderle KA, Chung MK, Rayadurgam S, Miller MA, Obuchowski NA, Lindsay BD. Occupational and patient radiation doses in a modern cardiac electrophysiology laboratory. J Interv Card Electrophysiol 2018 Oct 2. Epub 2018.
Robins M, Kalpathy-Cramer J, Obuchowski NA, Buckler A, Athelogou M, Jarecha R, Petrick N, Pezeshk A, Sahiner B, Samei E. Evaluation of Simulated Lesions as Surrogates to Clinical Lesions for Thoracic CT Volumetry: The Results of an International Challenge. Academic Radiology 2018 Sep 12. Epub 2018.
Alvin MD, Lubelski D, Alam R, Williams S, Obuchowski NA, Steinmetz MP, Wang JC, Melillo AJ, Pahwa A, Benzel EC, Modic MT, Quencer R, Mroz TE. Spine Surgeon Treatment Variability: The Impact on Costs. Global Spine J 2018 Aug 15; 8: 498-506.
Mantripragada VP, Bova WA, Boehm C, Piuzzi NS, Obuchowski NA, Midura RJ, Muschler GF. Progenitor cells from different zones of human cartilage and their correlation with histopathological osteoarthritis progression. J Orthop Res 2018; 36: 1728-1738.
Mantripragada VP, Piuzzi NS, Zachos T, Obuchowski NA, Muschler GF, Midura RJ. High occurrence of osteoarthritic histopathological features unaccounted for by traditional scoring systems in lateral femoral condyles from total knee arthroplasty patients with varus alignment. Acta Orthop 2018; 89: 197-203.
Bhatt KM, Tandon YK, Graham R, Lau CT, Lempel JK, Azok JT, Mazzone PJ, Schneider E, Obuchowski NA, Bolen MA. Electromagnetic navigational bronchoscopy versus CT-guided percutaneous sampling of peripheral indeterminate pulmonary nodules: a cohort study. Radiology 2018; 286: 1052-1061.
Obuchowski NA. Interpreting Change in Quantitative Imaging Biomarkers. Acad Radiol 2018; 25: 372-379.
SubhasN, PursykoCP, Polster JM, Obuchowski NA, Primak AN, Dong FF, and Herts BR. Dose Reduction With Dedicated CT Metal Artifact Reduction Algorithm: CT Phantom Study. Am J Roentgenol 2018; 210: 593-600.
Jones MH, Spindler KP, Andrish JT, Cox CL, Dunn WR, Duryea J, Duong CL, Flanigan DC, Fleming BC, Huston LJ, Kaeding CC, Matava MJ, Obuchowski NA, Oksendahl HJ, Parker RD, Scaramuzza EA, Smith MV, Winalski CS, Wright RW, Reinke EK. Differences in the Lateral Compartment Joint Space Width After Anterior Cruciate Ligament Reconstruction: Data From the MOON Onsite Cohort. Am J Sports Med 2018; 46: 876-882.
Mikkilineni H, Delzell PB, Andrish J, Bullen J, Obuchowski NA, Subhas N, Polster JM, Schils JP. Ultrasound evaluation of infrapatellar fat pad impingement: An exploratory prospective study. Knee 2018; 25: 279-285.
Sheahan M, Ma X, Paik D, Obuchowski NA, St. Pierre S, Newman WP, Rae G, Perlman ES,Rosol M, Keith JC, Buckler AJ. Atherosclerotic plaque tissue: noninvasive quantitative assessment of characteristics with software-aided measurements from conventional CT angiography. Radiology 2018; 286: 622-631.
Yokoo T, Serai SD, Pirasteh A, Bshir MR, Hamilton G, Hernando D, Hu HH, Hetterich H, Kuhn JP, Kukuk GM, Loomba R, Middleton MS, Obuchowski NA, Song JS, Tang A, Wu X, Reeder SB, Sirlin CB. Linearity, bias, and precision of hepatic proton density fat fraction measurements by using MR Imaging: a meta-analysis. Radiology 2018; 286: 486-498.
Bandos AI, Obuchowski NA. Evaluation of diagnostic accuracy in free-response detection-localization tasks using ROC tools. Stat Methods Med Res 2018 Jan 1. Epub 2018 Jan 1.