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RegisterFieller’s (‘fiducial’) confidence interval [General Statistics]
Dear ElMaestro,
Correct in so far if we use the approximation that the estimate of µR is (statistically) greater than zero. A very reasonable assumption for the usual metrics AUC and Cmax IMHO.
But this has than nothing to do with Fieller’s (‘fiducial’) confidence interval, a more correct method for deriving a confidence interval for the ratio of untransformed PK metrics.
PowerTOST has for this case the functions
Have a look into the man pages of these functions and notice that these functions don't have a
may help.
Especially chapter 10 Equivalence assessment for clinical endpoints.
If you don't own this book, gimme a hint.
❝ For such cases we are setting logscale to False, right?
Correct in so far if we use the approximation that the estimate of µR is (statistically) greater than zero. A very reasonable assumption for the usual metrics AUC and Cmax IMHO.
But this has than nothing to do with Fieller’s (‘fiducial’) confidence interval, a more correct method for deriving a confidence interval for the ratio of untransformed PK metrics.
PowerTOST has for this case the functions
- CI.RatioF()
- power.RatioF()
- sampleN.RatioF()Have a look into the man pages of these functions and notice that these functions don't have a
logscale argument.❝ I will read up on the other stuff. Still not sure how to derive the CI. ...
Hauschke D, Steinijans VW, Pigeot I.
Bioequivalence Studies in Drug Development
Chichester: John Wiley; 2007
may help.
Especially chapter 10 Equivalence assessment for clinical endpoints.
If you don't own this book, gimme a hint.
—
Regards,
Detlew
Regards,
Detlew
Complete thread:
- On CI calculation, untransformed metrics ElMaestro 2019-11-29 03:40
![[Mix]](https://static.bebac.at/img/mix.png "open in Mix view")
- Fieller’s (‘fiducial’) confidence interval Helmut 2019-11-29 10:03
- Fieller’s (‘fiducial’) confidence interval ElMaestro 2019-11-29 15:53
- Fieller’s (‘fiducial’) confidence intervald_labes 2019-11-29 17:20
- Fieller’s (‘fiducial’) confidence interval ElMaestro 2019-11-30 05:11
- power.TOST with logscale=FALSE d_labes 2019-11-30 14:01
- Fieller’s (‘fiducial’) confidence interval apapanas 2026-03-12 10:54
- Fieller’s (‘fiducial’) confidence interval ElMaestro 2019-11-30 05:11
- Fieller’s (‘fiducial’) confidence intervald_labes 2019-11-29 17:20
- Fieller’s (‘fiducial’) confidence interval ElMaestro 2019-11-29 15:53
- On CI calculation, untransformed metrics PharmCat 2019-11-29 12:05
- Fieller’s (‘fiducial’) confidence interval Helmut 2019-11-29 10:03
Ing. Helmut Schütz