Methodological issues in design and analysis of a matched case–control study of a vaccine's effectiveness
Accepted 16 February 2007. published online 11 June 2007.
Abstract
Objective
Case–control studies of the effectiveness of a vaccine are useful to answer important questions, such as the effectiveness of a vaccine over time, that usually are not addressed by prelicensure clinical trials of the vaccine's efficacy. This report describes methodological issues related to design and analysis that were used to determine the effects of time since vaccination and age at the time of vaccination.
Study Design and Setting
A matched case–control study of the effectiveness of varicella vaccine was conducted.
Results
Sampling procedures and conditional logistic regression models including interaction terms are described.
Conclusion
Use of these methods will allow investigators to assess the effects of a wide range of variables, such as time since vaccination and age at the time of vaccination, on the effectiveness of a vaccine.
aDepartment of Epidemiology and Public Health, Yale University School of Medicine, New Haven, CT, USA
bDepartment of Preventive Medicine and Biometrics, University of Colorado School of Medicine and Health Sciences Center, Denver, CO, USA
cDepartment of Pediatrics, Yale University School of Medicine, 333 Cedar Street, P.O. Box 208064, New Haven, CT 06520-8064, USA
dDepartment of General Clinical Research Center, Yale University School of Medicine, New Haven, CT, USA
Corresponding author. Department of Pediatrics, Yale University School of Medicine, 333 Cedar Street, P.O. Box 208064, New Haven, CT 06520-8064, USA. Tel.: 203-688-4555; fax: 203-785-3932.