Computed Tomography for Diagnosing Pulmonary Embolism A Health Technology Assessment The Health Technology Assessment Unit, University of Calgary March 21, 2017 1 Acknowledgements This report is authored by Laura E. Dowsett, Fiona Clement, Vishva Danthurebandara, Diane Lorenzetti, Kelsey Brooks, Dolly Han, Gail MacKean, Fartoon Siad, Tom Noseworthy and Eldon Spackman on behalf of the HTA Unit at the University of Calgary. Dr. Eldon Spackman has received personal non-specific financial compensation from Roboleo & Co and Astellas Pharma. The remaining authors declare no conflict of interests. This research was supported by the Health Technology Review (HTR), Province of BC. The views expressed herein do not necessarily represent those of the Government of British Columbia, the British Columbia Health Authorities, or any other agency. We gratefully acknowledge the valuable contributions of the key informants and thank them for their support. We also acknowledge the collaboration with CADTH to complete the cost- effectiveness model. 2 Contents Abbreviations .................................................................................................................................. 7 Executive Summary ........................................................................................................................ 8 1 Purpose of this Health Technology Assessment ................................................................... 12 2 Research Question and Research Objectives ........................................................................ 12 3 Background ........................................................................................................................... 13 3.1 Pulmonary Embolism Overview .................................................................................... 13 3.2 Prevalence and Incidence ............................................................................................... 13 3.3 Disease Progression and Severity .................................................................................. 14 3.4 Risk Factors .................................................................................................................... 15 3.5 Diagnosis ........................................................................................................................ 16 3.6 Risk Stratification ........................................................................................................... 18 3.7 Diagnostic Tests for PE .................................................................................................. 21 3.8 Computed tomography (CT) Overview ......................................................................... 27 3.9 Treatment ....................................................................................................................... 32 3.10 Clinical Practice Guidelines ....................................................................................... 34 3.11 Ongoing Research....................................................................................................... 38 4 Diagnostic Accuracy ............................................................................................................. 39 4.1 Objective ........................................................................................................................ 39 4.2 Methods .......................................................................................................................... 39 4.3 Results ............................................................................................................................ 42 4.4 Conclusions .................................................................................................................... 50 5 British Columbia Context and Physician Perspectives ......................................................... 52 5.1 Purpose ........................................................................................................................... 52 5.2 Methods .......................................................................................................................... 52 5.3 Findings .......................................................................................................................... 52 5.4 Conclusion ...................................................................................................................... 59 6 Patient Perspective Systematic Review ................................................................................ 61 6.1 Objective ........................................................................................................................ 61 6.2 Methods .......................................................................................................................... 61 6.3 Results ............................................................................................................................ 62 3 6.4 Discussion ...................................................................................................................... 65 7 Appropriate Use of CT.......................................................................................................... 66 7.1 Objective ........................................................................................................................ 66 7.2 Methods .......................................................................................................................... 66 7.3 Results ............................................................................................................................ 68 7.4 Discussion ...................................................................................................................... 75 8 Cost-effectiveness and Economic Impact ............................................................................. 76 8.1 Objective ........................................................................................................................ 77 8.2 Overview of Previous Studies ........................................................................................ 77 8.3 Methods .......................................................................................................................... 84 8.4 Results .......................................................................................................................... 101 8.5 Budget Impact Analysis ............................................................................................... 113 8.6 Discussion .................................................................................................................... 118 8.7 Conclusion .................................................................................................................... 119 9 Overall Conclusions ............................................................................................................ 119 10 References ........................................................................................................................... 121 Appendix A: Diagnostic Accuracy ............................................................................................. 133 Appendix B: Patient Perspective ................................................................................................ 156 Appendix C: Appropriate Use of CT .......................................................................................... 158 Search Strategy ....................................................................................................................... 158 Appendix D: Cost-Effectiveness and Budget Impact Analysis .............................................. 175 Search Strategy ....................................................................................................................... 175 4 Tables Table 1: Inherited or acquired Predisposing factors for PE 9........................................................ 16 Table 2: Wells Criteria Tool31 ....................................................................................................... 19 Table 3: Revised Geneva Score Tool 34 ........................................................................................ 20 Table 4: CT Scan Parameters ........................................................................................................ 30 Table 5: Thrombosis Canada, Recommendations for Duration of Treatment of PE or DVT ...... 33 Table 6. Inclusion and Exclusion Criteria for Clinical Systematic Review ................................. 40 Table 7: Synthesis of Characteristics of Included Studies ............................................................ 44 Table 8: Between study variability of CT scan parameters .......................................................... 46 Table 9. Quality Assessment of Included Randomized Controlled Trial ..................................... 47 Table 10. Inclusion and Exclusion Criteria for Systematic Review ............................................. 62 Table 11: Summary of Included Study ......................................................................................... 64 Table 12. Inclusion and Exclusion Criteria for Systematic Review ............................................. 67 Table 13: Synthesis of Interventions ............................................................................................. 70 Table 14. Outcomes of Included Studies .....................................................................................