Max Paul Rosen MD, MPH, Presenter: Consultant, Perceptive Informatics, Inc Stockholder, Anvita Inc

Ahmed Ghouri MD, Abstract Co-Author: Founder, Anvita, Inc Officer, Anvita, Inc

Lawrence Markson MD, Abstract Co-Author: Nothing to Disclose

Katherine Dallow MD, Abstract Co-Author: Nothing to Disclose

Richard Parker MD, Abstract Co-Author: Nothing to Disclose

John D Halamka, Abstract Co-Author: Board of Directors, Anvita, Inc

Expansion of high-tech outpatient imaging over the past decade has contributed to rising health care costs. Many strategies (pre-authorization, computer decision support (CDS), high co-pays or deductibles) have been employed to slow or reduce the growth of outpatient imaging. However, none of these strategies actually measure the impact of outpatient imaging on clinical decision making. The purpose of our study was to assess the impact of high-tech imaging on the ordering physician’s level of certainty in his/her pre-test diagnosis.

Between July 14, 2010 and February 28, 2011, 1,950 CT/MRI scans were ordered via on-line CDS. At the time of order entry, physicians were asked to record their pre-test level of diagnostic certainty (on a scale of 0 to 100) and most likely diagnosis (Dx) . After viewing the final report, physicians were asked to record their post-test level of diagnostic certainty and leading post-test Dx.

Participation was declined in 998/1950 (51.2%) orders. Post-test data was not provided for 717/1950 (36.8%). Post-test data was provided for 234/1950 (12%). In 44/234 (18.8%) cases initial Dx certainty was low (<25%) and increased in 27/44 (61.4%). Initial Dx certainty was intermediate (25% to 74%) in 104/234 (44.4%) cases and decreased in 38/104 (36.5%), remained intermediate in 27/104 (26.0%) and increased in 39/104 (37.8%). Initial Dx certainty was high (>75%) in 86/234 (36.8%) cases and decreased in 30/86 (34.9%) and remained high in 56/86 (65.1%). Overall Dx certainty increased more than 50 points in 42/234 (18%), decreased by more than 50 points in 29/234 (12.4%), and was relatively unchanged in 163/234 (69.7%). In 41/234 (17.5%) level of Dx certainty remained intermediate following high-tech imaging.  

The impact of high-tech outpatient imaging on level of Dx certainty is varied. In many cases the use of CT or MRI either did not lead to increased Dx certainty or actually lead to decreased Dx certainty. The advent of data bases generated by CDS offers the opportunity for sophisticated data mining to help develop rules which may enhance the impact of high-tech imaging on physician’s level of Dx certainty.

CDS offers the ability to perform sophisticated data analysis which may guide MDs to tests which are quantitatively associated with the largest increase in Dx certainty for specific clinical scenarios

Rosen, M, Ghouri, A, Markson, L, Dallow, K, Parker, R, Halamka, J, Impact of High-Tech Outpatient Imaging on Physician's Level of Diagnostic Certainty.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11034239.html