I am doing meta-analysis between 2 arms using meta package and used subset if number of events are available in all comparison arms but I got weird results (NA in some cells) then I tried to investigate the cause using the following code
data$Studlab<- as.factor(data$Studlab)
show<- cbind(Studlab,IMA.number.of.grafts.TOTAL, IMA.MGF.overall,IMA.MGF.overall.SD, Venous.TOTAL.number.of.grafts, Venous.MGF.overall, Venous.MGF.overall.SD);show
It gave me numbers instead of authors in studlab column
Original column is as follow
My original dataset is gigantic. Any advice is greatly appreciated.