Hi, a collegue has send me an excel sheet with some plasma values, and now he wants to know the AUC steady state. I took a look at the CRAN taskviews, and came up with PK, PKtools, ... The AUC calculation, no problem with that, but how do I calculate the steady state? One way of thinking was with the aid of multiple t-test, to find where we couldn't find difference between the different measuring points, and take this as steady state, but I'm not sure that this is the right way. As I'm not home in the pharmacokinetic world, I was hoping someone with some more experience can shed some light on this (altough for me) dark material. Kind Regards Bart PS: Here some example data: dat<- structure(list(Sample = c(1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L), tijd = c(12L, 36L, 60L, 84L, 108L, 132L, 12L, 36L, 60L, 84L, 108L, 132L), conc = c(0.621518061431366, 0.87531564366726, 0.916311538568891, 0.880947260781843, 0.852202744098934, 0.218909173985895, 1.22305496551836, 1.30075841227452, 0.995918019674464, 1.33214099618361, 1.42613784296527, 0.290928921761672)), .Names = c("Sample", "Time", "conc"), row.names = c(NA, -12L), class = "data.frame") [[alternative HTML version deleted]]