Interventions to control nosocomial infections : study designs and statistical issues

Wolkewitz, M., Barnett, A.G., Palomar Martinez, M., Frank, U., & Schumacher, M. (2014) Interventions to control nosocomial infections : study designs and statistical issues. Journal of Hospital Infection, 86(2), pp. 77-82.

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There is a wide range of potential study designs for intervention studies to decrease nosocomial infections in hospitals. The analysis is complex due to competing events, clustering, multiple timescales and time-dependent period and intervention variables. This review considers the popular pre-post quasi-experimental design and compares it with randomized designs. Randomization can be done in several ways: randomization of the cluster [intensive care unit (ICU) or hospital] in a parallel design; randomization of the sequence in a cross-over design; and randomization of the time of intervention in a stepped-wedge design. We introduce each design in the context of nosocomial infections and discuss the designs with respect to the following key points: bias, control for nonintervention factors, and generalizability. Statistical issues are discussed. A pre-post-intervention design is often the only choice that will be informative for a retrospective analysis of an outbreak setting. It can be seen as a pilot study with further, more rigorous designs needed to establish causality. To yield internally valid results, randomization is needed. Generally, the first choice in terms of the internal validity should be a parallel cluster randomized trial. However, generalizability might be stronger in a stepped-wedge design because a wider range of ICU clinicians may be convinced to participate, especially if there are pilot studies with promising results. For analysis, the use of extended competing risk models is recommended.

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ID Code: 79717
Item Type: Journal Article
Refereed: Yes
Additional URLs:
Keywords: Cluster, competing risks, quasi-experiment, randomization, stepped-wedge design, study design, timescale, hospital acquired infection, statistics
DOI: 10.1016/j.jhin.2013.09.015
ISSN: 1532-2939
Divisions: Current > QUT Faculties and Divisions > Faculty of Health
Current > Institutes > Institute of Health and Biomedical Innovation
Current > Schools > School of Public Health & Social Work
Copyright Owner: Copyright 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved
Copyright Statement: NOTICE: this is the author’s version of a work that was accepted for publication in Journal of Hospital Infection. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Hospital Infection, [86, 2, (February 2014)] DOI: 10.1016/j.jhin.2013.09.015
Deposited On: 06 Jan 2015 01:45
Last Modified: 10 Mar 2015 05:22

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