Bioequivalence and Bioavailability Forum

Hi John!

❝ How does one back calculate the intrasubject CV (and MSE?) from the 90% confidence interval obtained for a three way partial replicate study? Can it be done using the same suggestion that you presented in your previous slides?

Essentially yes. You have to get the degrees of freedom right. See Detlew’s post. For your log AUCt data and my CI (ignoring the fact that you had 16, 17, and 18 subjects in the three sequences) I got:

require(PowerTOST)
CVfromCI(lower=0.874898, upper=1.02586, n=51, design="2x3x3", alpha=0.05)
[1] 0.2850511

…or better?*

require(PowerTOST)
CVfromCI(lower=0.874898, upper=1.02586, n=51, design="2x3x3", alpha=0.05, robust=TRUE)
[1] 0.2820788

But: According to this discussion I duno whether the CI is correct.

Maybe it’s better to go with the linearized CI from the RSABE-code instead (no mixed-effects limbo). With the 90% CI of 0.874723 – 1.02766 I got:

require(PowerTOST)
CVfromCI(lower=0.874723, upper=1.02766, n=51, design="2x3x3", alpha=0.05)
[1] 0.2886897

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• Documentation of PowerTOST/CVfromCI.

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P.S.: Any news from Donald Schuirmann?