Journal article

The influence of incomplete case ascertainment on measures of vaccine efficacy

Yue Wu, Julie A Marsh, Emma S McBryde, Thomas L Snelling

VACCINE | ELSEVIER SCI LTD | Published : 2018

Abstract

BACKGROUND: Motivated by the unexplained variation in the performance of some vaccines across different settings, we extend previous theoretical work to consider the potential impact of incomplete case ascertainment on measures of vaccine efficacy (VE), which is more likely in subclinical or clinically unimportant infections, such as rotavirus gastroenteritis. METHODS: By simulating the measurement of VE under outbreak conditions using a discrete time stochastic SIR model, we compare three commonly used measures, VERisk, VERate, and VEHazard, calculated respectively based on risk ratio, rate ratio and hazard ratio of disease. We investigate how these measures are influenced by factors such a..

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