Bioequivalence and Bioavailability Forum

replicateBE solution with interactions [General Sta­tis­tics]

posted by mittyri – Russia, 2019-12-23 13:30 (233 d 07:56 ago) – Posting: # 21020
Views: 2,989
(edited by mittyri on 2019-12-23 14:05)

Dear Nastya,

whenever possible use simple solutions, at least till the moment you must dive into mixed models galaxy

And more: interaction terms are not the same in SAS and R
take a look at method.B implementation inside replicateBE package
I just modified it a bit

library(replicateBE)
library(nlme)
alpha <- 0.05
options(contrasts=c("contr.treatment","contr.poly"))
Dataset <- rds01
Dataset$group<- factor(ifelse(as.numeric(levels(Dataset$subject))[Dataset$subject]<31, 1,2))
modB <- lme(log(PK) ~ sequence + group + sequence:group + period + period%in%group + treatment, random = ~1 | subject, na.action = na.omit, data = Dataset)

EMA.B <- summary(modB)
PE <- EMA.B$tTable["treatmentT", "Value"] # exp(PE) = 1.157275
CI <- exp(PE + c(-1, +1) * qt(1 - alpha, EMA.B$tTable["treatmentT", "DF"]) * EMA.B$tTable["treatmentT", "Std.Error"])
# CI = 1.071136 1.250340

Complete thread:

• Group by sequence interaction Mutasim 2019-08-07 13:16 
  • Group by sequence interaction, an urban myth? Helmut 2019-08-07 14:35
    • pristine, genuine, holy, magnificent, inexplicable beautiful variation ElMaestro 2019-08-08 10:06
      • I love your subject line! Helmut 2019-08-08 10:31
        • Group effect, did you miss it? Astea 2019-12-21 14:12
          • Group effect, did you miss it? PharmCat 2019-12-22 01:37
          • Group effect: the endless story Helmut 2019-12-22 10:30
            • Group effect: the endless river Astea 2019-12-22 21:23
              • Group effect: the endless river PharmCat 2019-12-22 22:52
              • replicateBE solution with interactionsmittyri 2019-12-23 14:30
                • replicateBE solution with interactions Astea 2019-12-23 17:26
                  • datasets issues mittyri 2019-12-24 10:53
                  • datasets Helmut 2019-12-24 11:03
                    • datasets Astea 2019-12-24 19:18
                      • lmer / lme Helmut 2019-12-25 19:12
          • What do you mean exactly? Beholder 2019-12-27 13:44
            • What do you mean exactly? Astea 2019-12-29 21:59
              • ANOVA acc. to GL Helmut 2019-12-30 12:32