5 Different Observational Datasets: Pros & Cons Jay Giri, MD MPH Assistant Professor of Medicine Director, Peripheral Intervention Associate Director, Penn Cardiovascular Quality, Outcomes, & Evaluative Research Center Hospital of the University of Pennsylvania

Disclosure Statement of Financial Interest I, Jay Giri DO NOT have a financial interest/arrangement or affiliation with one or more organizations that could be perceived as a real or apparent conflict of interest in the context of the subject of this presentation.

Observational vs. RCT External validity vs. internal validity RCT – controls for treatment-selection bias

Therapies Do Not Benefit Everyone

An Example: Prasugrel vs. Clopidogrel Wiviott S, NEJM 2015

Why Outcomes? Direct relationship with quality assessment and continuous quality improvement Increasing interest in Big Data Close synergies with clinical care Possible (but not easy) to be an expert clinician and productive outcomes researcher

Datasets Administrative Database Registry Sub-Analysis of Randomized Trial DIY Meta-Analysis Cohort Level Patient-Level

Administrative Database Pros Very large numbers Unselected Populations Cons Covariates may not be rich for your question Innacurate Codes No outcome adjudication

Registries Pros Cons Large numbers, relatively unselected Well-designed clinical research forms for a given disease process, rich covariates Trained data abstractors Often, built-in statistical support Cons No endpoint adjudication Often Cross-Sectional

Sub-Analysis of RCT Pros Cons High quality data collection Often independent endpoint adjudication (including Core Labs) Cons Limited by primary experiment hypotheses Smaller total numbers Selected patient population Access to Data limited to trialists

DIY Pros Cons Ability to dive deeper into the data Investigator can select and assay covariates and outcomes with any degree of rigor Cons Small numbers Time

Meta-Analysis How heterogenous are the inclusion criteria and methods for your component studies?

Thank You! Peter Groeneveld, MD, MS Robert Yeh, MD, MS Penn Center for Cardiovascular Outcomes, Quality & Evaluative Research (CAVOQER)