Bioequivalence and Bioavailability Forum

CV(total) from CV(intra) and CV(inter) [Power / Sample Size]

posted by d_labes  – Berlin, Germany, 2015-08-27 10:48 (3946 d 13:30 ago) – Posting: # 15349
Views: 7,914

Dear BRN!

❝ I have intra and inter-cv, is there an easy way to calculate the total cv? An R code for example or any other suggestions are appreciated.

Have a look into Helmut's lectures, f.i. the Moscow lecture about sample size estimation, slide 18. If your design was 2x2x2 which gave you the intra and inter-CV, and if you obtained the CV's from log-transformed analysis.

Using the world-famous R package PowerTost you may use:

library(PowerTOST)
# Methylphenidate on slide 19, Helmut's Moscow lecture
# CV's as ratio
CVintra <- 0.070
CVinter <- 0.191
CVtotal <- mse2CV(CV2mse(CVintra)+CV2mse(CVinter))
print(CVtotal)

will give 0.2038621, i.e. 20.4%.

Complete thread:

• CV calculation avrahan 2014-09-17 21:40 
  • CV calculation Helmut 2014-09-18 01:21
    • CV calculation BRN 2015-08-26 16:52
      • CV(total) from CV(intra) and CV(inter)d_labes 2015-08-27 08:48