1. Research Design: The Progression of Study Designs that Address a Clinical Question

2. Edward P. Sloan, MD, MPH Associate Professor Dept of Emergency Medicine University of Illinois College of Medicine Chicago, IL

3. Attending Physician Emergency Medicine University of Illinois Hospital Our Lady of the Resurrection Medical Center

4. Overview Global Objectives Answer clinical questions Minimize work Get it done

5. Overview Session Objectives Know what options exist Examine the progression of designs Understand the linkage and rationale

6. Study Types Case report Case series Case-control study Prospective observational Prospective randomized

7. Case Report That was an interesting case… Why did that happen? That’s unusual. I’ll never do that again!

8. Case Report One patient An important observation A unique teaching point

9. Case Series Is this really unusual? Are there similar patients? Is there a trend? Should we look further?

10. Case Series Strengthens observation Identifies trends Suggests relationships Supports case-control study Supports prospective work

11. Case-Control Study Are the unusual pts different? What risk factors differ? Is it something we can change? Should we look further?

12. Case-Control Study Tests associations Utilizes diseased, OK patients May be last necessary step Supports prospective work

13. Prospective Observational What data was missing? Do we need consistent data? What do we wish to know? What about missing pts?

14. Prospective Observational Consistent data No missing patients Details future interventions Supports clinical changes

15. Prospective Interventional Now let’s compare 2 groups… Who will do better? Which way should we do it? Can we improve outcomes, reduce costs, enhance access?

16. Prospective Interventional Best research Costly, but complete Answers the questions Always causes new questions to be asked

17. A Real Life Example Abdominal trauma Peritoneal blood Is there an injury? Is an operation needed? Is there a better way?