ve {VEwaningVariant}

Retrieve the Estimated Vaccine Efficacy

Description

Uses a prior veWaningVariant() analysis to estimate the vaccine efficacy at the provided times since full efficacy.

Usage

ve(x, times = NULL, nTimes = 20L)

Arguments

x

An object of class VEwaningVariant. The object returned by a call to veWaningVariant()

times

A numeric vector object or NULL. The times since full efficacy at which the vaccine efficacy is to be estimated. If NULL, the times will be generated internally as a vector of length nTimes spanning the range [0, maxTime], where maxTime is the maximum time since vaccination present in the original analysis. Values provided outside of [0, maxTime] are ignored.

nTimes

An integer object. The number of time values at which estimates are obtained. The default is 20. If input times is a vector object, this input is ignored.

Details

When the variant under analysis is present only in the unblinded phase, vaccine efficacy cannot be estimated. In this case, ve() returns the relative infection rate at times t since full efficacy reached, defined as infection rate at time t = time since full efficacy reached divided by the infection rate at the time full efficacy is reached (t=0).

Value

A matrix object. The first column contains the times since full efficacy at which the estimates are provided; the second column contains estimated vaccine efficacy or relative infection rate (see Details); and the third is the standard error.

Examples

data(variantData)

set.seed(1234)

ind <- sample(1:nrow(variantData), 2000)
# NOTE: This sample size is chosen for example only -- larger data sets
# should be used.

res <- veWaningVariant(data = variantData[ind,], 
                       L = 52,  
                       gFunc = 'piece', 
                       v = c(15,30))

ve(x = res, times = c(10,20,30,40,50))