Ah, true! According to the documentation, function pvalstest_logrank takes as a parameter "The number of the column containing survival time". But instead of a number I had been supplying the column name, which seemed to work fine. When I noticed it didn't when the column name has spaces, I replaced it with `which(colnames(phenodata) == survival)` to have it as a number. But when that didn't do the trick, I realized it was the check.names=FALSE for the read.table that was needed. Still, didn't change the first thing back as now it matches what's said in the documentation.