I have the following data which show some values before and after a drug. I want to test whether the drug increased the mean. I think I should use Wilcoxon test, but I don't know what to do with missing values (NAs). Do I need to remove NAs and corresponding before values?
before after 2.2 NA 8.2 5.2 9.5 NA 10.5 4 12.5 6 10.5 3 9.7 10 11.5 NA