PowerTOST sample size EMA full replicate [🇷 for BE/BA]
Dear all!
I've noted that sample size, estimated with the help of PowerTOST's scABEL, depends on the difference between CV_T and CV_R.
Suppose we have a HVD with unknown CV (or CV is known in literature but it ranges widely through the studies). There could be a situation when CV_T and CV_R do not coincides. For example, CV_R=0.3 and CV_T=0.4. Then basing on the sampleN.scABEL for theta0=0.9 we need 48 subjects. But if we plan replicate study on the basis of CV=0.3 we get only 34 subjects. Moreover planing replicate study without scaling (sampleN.TOST) we get only 40 subjects. Here I post the graph for illustration purposes (scABEL2 denotes sampleN.scABEL(CV=c(CV_T, 0.3), theta0=0.9, design="2x2x4"))
Do I undestand correctly? If it so then there are always exist a miserable possibility that calculated by scABEL with CV_T=CV_R sample size would be insufficient?
I've noted that sample size, estimated with the help of PowerTOST's scABEL, depends on the difference between CV_T and CV_R.
Suppose we have a HVD with unknown CV (or CV is known in literature but it ranges widely through the studies). There could be a situation when CV_T and CV_R do not coincides. For example, CV_R=0.3 and CV_T=0.4. Then basing on the sampleN.scABEL for theta0=0.9 we need 48 subjects. But if we plan replicate study on the basis of CV=0.3 we get only 34 subjects. Moreover planing replicate study without scaling (sampleN.TOST) we get only 40 subjects. Here I post the graph for illustration purposes (scABEL2 denotes sampleN.scABEL(CV=c(CV_T, 0.3), theta0=0.9, design="2x2x4"))
Do I undestand correctly? If it so then there are always exist a miserable possibility that calculated by scABEL with CV_T=CV_R sample size would be insufficient?
—
"Being in minority, even a minority of one, did not make you mad"
"Being in minority, even a minority of one, did not make you mad"
Complete thread:
- PowerTOST sample size EMA full replicate Shuanghe 2016-03-07 18:04 [🇷 for BE/BA]
- merciless tester! Helmut 2016-03-07 18:56
- PowerTOST sample size EMA full replicate yjlee168 2016-03-07 20:15
- Merciless peer reviewers d_labes 2016-03-08 08:50
- PowerTOST V1.3-4 d_labes 2016-03-09 18:43
- PowerTOST sample size EMA full replicateAstea 2016-03-24 19:34
- RSABE is not bijective (lengthy answer) Helmut 2016-03-25 14:23
- RSABE is not bijective (lengthy answer) Astea 2016-03-27 21:07
- ABEL sample size examples Helmut 2016-03-28 00:42
- ABEL sample size: more power! (joke) mittyri 2016-03-28 21:54
- ABEL sample size examples Helmut 2016-03-28 00:42
- RSABE is not bijective (lengthy answer) Astea 2016-03-27 21:07
- RSABE is not bijective (lengthy answer) Helmut 2016-03-25 14:23