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Published on: November 16, 2016
The use and interpretation of quasi-experimental studies in infectious diseases
Anthony D Harris1, Douglas D Bradham, Mona Baumgarten
1Department of Epidemiology and Preventive Medicine, University of Maryland, Baltimore, Maryland 21201, USA. aharris@epi.umaryland.edu
Abstract:
Quasi-experimental study designs, sometimes called nonrandomized, pre-post-intervention study designs, are ubiquitous in the infectious diseases literature, particularly in the area of interventions aimed at decreasing the spread of antibiotic-resistant bacteria. Little has been written about the benefits and limitations of the quasi-experimental approach. This article outlines a hierarchy of quasi-experimental study design that is applicable to infectious diseases studies and that, if applied, may lead to sounder research and more-convincing causal links between infectious diseases interventions and outcomes.
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