I have a quick (and I'm sorry if silly) question.
I am using the metafor package and this function:
data<-escalc(measure = "RR", ai=1, bi=0, ci=43, di=443, append=TRUE)
to calculate the relative risk.
While my manual calculations say its 11.30 (log(RR)=2.425), the escalc function throws a 8.40 (log(RR)=2.13).
I actually took this values from a research paper, and know for a fact that 11.30 is the correct result, but I have no clue on why this calculation gives 8.40.
Any help is very welcome
When one of the cells is a 0, escalc applies the +1/2 continuity correction by default. If you don't want that, use add=0. See help(escalc).