Methodological issues in design and analysis of a matched case-control study of a vaccine's effectiveness.
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.


METHODS
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.


CONCLUSIONS
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.
Niccolai
Linda M
LM
Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, CT 06520-8064, USA.
Ogden
Lorraine G
LG
Muehlenbein
Catherine E
CE
Dziura
James D
JD
Vázquez
Marietta
M
Shapiro
Eugene D
ED
D000367:Age Factors; D016022:Case-Control Studies; D019433:Chickenpox Vaccine / Q000627:therapeutic use*; D015340:Epidemiologic Research Design; D006801:Humans; D016015:Logistic Models; D016017:Odds Ratio; D018579:Patient Selection; D018570:Risk Assessment; D013997:Time Factors; D016896:Treatment Outcome
D019433:Chickenpox Vaccine