Department of Biostatistics Seminar/Workshop Series

Pragmatic Trials

James H. Ware, PhD

Frederick Mosteller Professor of Biostatistics, Associate Dean for Clinical and Translational Science, Department of Biostatistics, Harvard University School of Public Health

Tuesday, January 10, 3:00-4:00pm, 898-J PRB

The comparative effectiveness initiative included in the 2010 healthcare reform legislation, and calls from Congress for greater attention to the impact of biomedical research on human health, have prompted renewed interest in the pragmatic trial as a strategy for evaluating healthcare interventions. In 1967, Schwartz and Lellouch defined pragmatic trials as trials designed to compare healthcare interventions “under the conditions in which they would be applied in practice” and contrasted this approach with the explanatory trial, a trial designed to determine whether a treatment is effective under ideal, experimental conditions. Though most trials involve elements of both the pragmatic and explanatory approach, the distinction can help investigators define the purposes of their own trial and guide design decisions.

This talk will begin with a description of the defining characteristics of pragmatic trials and the strengths and limitations of the approach. A recent pragmatic trial of the treatment of first-line treatment of asthma will then be reviewed. This review will illustrate the principal that the pragmatic approach can require tradeoffs between generalizability (external validity) and strength of design (internal validity). We argue that pragmatic trials have an important role in support of evidence-based medicine when designed and interpreted appropriately.