Bioequivalence and Bioavailability Forum • R-Code for Power in 2×2 Cross-over

R-Code for Power in 2×2 Cross-over [🇷 for BE/BA]

posted by ElMaestro – Denmark, 2021-12-02 16:15 (1294 d 16:37 ago) – Posting: # 22684
Views: 12,455

Hello Brus,

❝ I am not an expert in R, and I am trying to adapt your example of power calculation with plot replesentation, but for the calculation of the sample size. My objetive is to plot a graphicala representation with ratio in X axis and sample size in Y axis and setting the CV and power as a fixed value.

Here's something basic to get you started. I assume you already have the PowerTOST package on your system.

Try.this=function(CV=0.2, tpow=0.8)

{

 library(PowerTOST)

 x=c(85:120)/100

 y=rep(NA, length(x))

 for (i in 1:length(x))

  y[i]= sampleN.TOST(CV=CV, targetpower=tpow, theta0=x[i])[1,7]


 plot(x,y, col="red", xlab ="GMR", ylab="Sample size")



 lines(x,y, col="red")

 return(0)

}



Try.this(CV=0.3, tpow=0.9)

Can be refined with designs and multipanel options and what not. :-)

PS: Correct, I am not entirely comfy with the tapply, sapply, apply family of functions.

—
Pass or fail!
ElMaestro

Complete thread:

R-Code for Power in 2×2 Cross-over Helmut 2006-12-28 21:33
- Power in Diletti's sample size table Helmut 2007-01-01 23:59
  - Approximate Power Helmut 2007-01-06 15:17
    - Power Calculation for replicate crossover design mathews 2008-04-03 13:19
      - Power Calculation for replicate crossover design Helmut 2008-04-03 13:49
        
        Power Calculation for replicate crossover design mathews 2008-04-04 13:21
    - Exact Power Helmut 2009-09-25 19:20
      - Exact Power ElMaestro 2009-09-27 23:27
        
        Software validation Helmut 2009-09-28 15:21
        
        All the important answers are here! ElMaestro 2009-09-28 19:12
        
        All the important answers are here! Helmut 2009-09-28 19:52
        
        All the important answers are here! ElMaestro 2009-09-28 20:18
        All the important answers are here! yjlee168 2009-09-28 21:30
        
        All the important answers are here! Helmut 2009-09-28 23:18
        
        42! SASophylistic power oracle d_labes 2009-09-29 13:37
        
        Al Gore Rhythms Helmut 2009-09-29 14:52
        
        Al Gore Rhythms ElMaestro 2009-09-29 18:14
        Al Gore Rhythms yjlee168 2009-09-29 23:55
        
        All the important answers are here! yjlee168 2009-09-29 23:49
- R-Code for Power in 2×2 Cross-over KDA 2019-01-23 04:24
  - R-Code for Power in 2×2 Cross-over Ohlbe 2019-01-27 18:24
- R-Code for Power in 2×2 Cross-over Brus 2021-12-02 15:00
  - R-Code for Power in 2×2 Cross-overElMaestro 2021-12-02 15:15
    - R-Code for Power in 2×2 Cross-over Helmut 2021-12-02 17:30
  - R-Code for Power in 2×2 Cross-over Helmut 2021-12-02 16:57