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Statistical Analysis of 2 × 2 Tables

Published online by Cambridge University Press:  21 June 2016

Louise-Anne McNutt
Division of Biostatistics, College of Medicine, The University of Iowa, Iowa City, Iowa
Robert F. Woolson*
Division of Biostatistics, College of Medicine, The University of Iowa, Iowa City, Iowa
Division of Biostatistics, 2811 A Steindler Bldg, University of Iowa Hospitals and Clinics, Iowa City, IA 52242


Clinical epidemiologic studies often focus on the identification of risk factors associated with hospital-acquired infections and the subsequent effects of preventive measures. Two study designs commonly used are the prospective design and the retrospective design. Both of these designs and the associated data collection issues were defined and discussed in the first article of this series. This article reviews the statistical analysis for a dichotomous risk factor and the presence or absence of a given disease for unmatched data. We focus our attention primarily on the unmatched prospective study, although we present formulae for the retrospective study as well.

Special Sections
Copyright © The Society for Healthcare Epidemiology of America 1988

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