simvee: Simulate data from a vaccine efficacy trial
In fluvee/wave: Waning Vaccine Effectiveness

View source: R/simvee.R

simvee

R Documentation

Simulate data from a vaccine efficacy trial

Description

This function simulates data from an ideal randomized placebo-controlled vaccine trial. Each study participant is randomly assigned a binary vaccination status V, where V=1 indicates a vaccine recipient and V=0 indicates a placebo recipient, i.e., an unvaccinated person. We assume that all study participants receive the vaccine or the placebo on the same calendar day, just prior to the onset of the study. The vaccine is assumed ‘leaky’, i.e., the hazard of infection of a vaccinated person is a fraction of the hazard of an unvaccinated. The parameters in the basic model are as follows: * lambda_dv= the probability that a participant of vaccination status V=v who was uninfected at the end of day d-1 becomes infected on day d. Then the daily hazards of infection for a vaccinee and a non-vaccinees are lambda_d1 and lambda_d0, respectively. * theta_d = lambda_d1/lambda_d0 is the ratio of the hazards of a vaccinee and a non-vaccinee on day d. Then the TVE on day d is 1- theta_d.

Usage

simvee(params, simNum)

Arguments

`params`	list of input parameters
`simNum`	number of simulations

Details

The simulation program iterates over days. On each day, each susceptible study participant may become infected, and the probability of this event equals to her/his hazard of infection on that day. The input parameters of the simulation program are the daily hazards of infection for unvaccinated persons lambda_d0 and the hazard ratios theta_d. The output is an ‘outcomes file’ with one record for each study participant. This record includes the binary vaccination status V, and a variable DINF which gives the day on which s/he became infected. For a participant who did not become infected during the study, DINF=0.