Developing a Protocol for Observational Comparative
Total Page:16
File Type:pdf, Size:1020Kb
Developing a Protocol for Observational Comparative Effectiveness Research A User’s Guide The Agency for Healthcare Research and Quality’s (AHRQ) Effective Health Care Program conducts and supports research focused on the outcomes, effectiveness, comparative clinical effectiveness, and appropriateness of pharmaceuticals, devices, and health care services. More information on the Effective Health Care Program and electronic copies of this report can be found at www.effectivehealthcare.ahrq. gov. This report was produced under contract to AHRQ by the Brigham and Women’s Hospital DEcIDE (Developing Evidence to Inform Decisions about Effectiveness) Methods Center and Quintiles Outcomes under Contract No. 290-2005-0016-I and 290-2005-0035-1. The AHRQ Task Order Officer for this project was Parivash Nourjah, Ph.D. The findings and conclusions in this document are those of the authors, who are responsible for its contents; the findings and conclusions do not necessarily represent the views of AHRQ or the U.S. Department of Health and Human Services. Therefore, no statement in this report should be construed as an official position of AHRQ or the U.S. Department of Health and Human Services. Persons using assistive technology may not be able to fully access information in this report. For assistance contact [email protected]. None of the investigators have any affiliations or financial involvement that conflicts with the material presented in this report. Copyright Information: Developing a Protocol for Observational Comparative Effectiveness Research: A User’s Guide is copyrighted by the Agency for Healthcare Research and Quality (AHRQ). The product and its contents may be used and incorporated into other materials on the following three conditions: (1) the contents are not changed in any way (including covers and front matter), (2) no fee is charged by the reproducer of the product or its contents for its use, and (3) the user obtains permission from the copyright holders identified therein for materials noted as copyrighted by others. The product may not be sold for profit or incorporated into any profitmaking venture without the expressed written permission of AHRQ. Specifically: 1. When the document is reprinted, it must be reprinted in its entirety without any changes. 2. When parts of the document are used or quoted, the following citation should be used. Suggested Citation: Velentgas P, Dreyer NA, Nourjah P, Smith SR, Torchia MM, eds. Developing a Protocol for Observational Comparative Effectiveness Research: A User’s Guide. AHRQ Publication No. 12(13)-EHC099. Rockville, MD: Agency for Healthcare Research and Quality; January 2013. www.effectivehealthcare.ahrq.gov/ Methods-OCER.cfm. Suggested citations for individual chapters are provided after the lists of authors and reviewers. Developing a Protocol for Observational Comparative Effectiveness Research: A User’s Guide Prepared for: Agency for Healthcare Research and Quality U.S. Department of Health and Human Services 540 Gaither Road Rockville, MD 20850 www.ahrq.gov Prepared by: Quintiles Outcome Cambridge, MA Contract No. 290-2005-0016-I and 290-2005-0035-I Editors: Priscilla Velentgas, Ph.D. Nancy A. Dreyer, M.P.H., Ph.D. Parivash Nourjah, Ph.D. Scott R. Smith, Ph.D. Marion M. Torchia, Ph.D. AHRQ Publication No. 12(13)-EHC099 January 2013 Acknowledgments The editors would like to acknowledge the efforts of the following individuals who contributed to this User’s Guide: Sebastian Schneeweiss, John D. Seeger, and Elizabeth Robinson of the Brigham and Women’s Hospital DEcIDE Methods Center; and Michelle Leavy, Anna Estrella, Aaron Mendelsohn, and Allison Bryant of Quintiles Outcome. We would especially like to thank April Duddy of Quintiles Outcome, who served as the managing editor for this guide. We also would like to thank the staff of AHRQ’s Office of Communications and Knowledge Transfer, who guided the User’s Guide through the editorial process, starting with the overall guidance provided by Sandy Cummings, the editorial skills provided by Marion Torchia and Chris Heidenrich, and the design and layout provided by Frances Eisel. And finally, we want to express our appreciation for the multiple contributions of Dr. Patrick Arbogast, author of Chapter 10. We were privileged to work with Patrick, who died before this project was completed. His positive, collegial spirit is very much missed. ii Contents Introduction to Developing a Protocol for Observational Comparative Effectiveness Research: A User’s Guide ............................................................................................................................................. 1 Background ........................................................................................................................................... 1 Aims of the User’s Guide Related to the Design of Observational CER Protocols .............................. 2 Summary and Conclusion ..................................................................................................................... 4 References............................................................................................................................................. 5 Chapter 1. Study Objectives and Questions .......................................................................................... 7 Abstract ................................................................................................................................................. 7 Overview ............................................................................................................................................... 7 Identifying Decisions, Decisionmakers, Actions, and Context ............................................................ 9 Synthesizing the Current Knowledge Base .......................................................................................... 9 Conceptualizing the Research Problem .............................................................................................. 10 Determining the Stage of Knowledge Development for the Study Design ........................................ 11 Defining and Refining Study Questions Using PICOTS Framework ................................................. 12 Endpoints .................................................................................................................................... 13 Discussing Evidentiary Need and Uncertainty ................................................................................... 13 Additional Considerations When Considering Evidentiary Needs ............................................. 15 Specifying Magnitude of Effect .......................................................................................................... 16 iii Challenges to Developing Study Questions and Initial Solutions ...................................................... 17 Summary and Conclusion ................................................................................................................... 17 Checklist: Guidance and Key Considerations for Developing Study Objectives and Questions for Observational CER Protocols ............................................................................................................. 18 References........................................................................................................................................... 19 Chapter 2. Study Design Considerations ............................................................................................. 21 Abstract ............................................................................................................................................... 21 Introduction......................................................................................................................................... 21 Issues of Bias in Observational CER .................................................................................................. 22 Basic Epidemiologic Study Designs ................................................................................................... 22 Cohort Study Design ................................................................................................................... 24 Case-Control Study Design ........................................................................................................ 25 Case-Cohort Study Design ......................................................................................................... 26 Other Epidemiological Study Designs Relevant to CER .................................................................... 26 Case-Crossover Design ............................................................................................................... 26 Case–Time Controlled Design .................................................................................................... 27 Self-Controlled Case-Series Design ........................................................................................... 27 Study Design Features ........................................................................................................................ 28 Study Setting ............................................................................................................................... 28 Inclusion and Exclusion Criteria ................................................................................................. 28 Developing an Observational