Bioequivalence and Bioavailability Forum • Deep shit

Deep shit [RSABE / ABEL]

posted by Mikalai – Belarus, 2020-01-31 16:07 – Posting: # 21121
Views: 8,166

Dear Helmut

» Duno what you mean. Are you considering the sample size of a 2×2×2 crossover? The sample size of the 2-period 4-sequence full replicate is ~½ though the number of treatments / biosamples (driving the study cost) are essentially the same.
» CV (%) ABE.2x2x2 ABE.2x2x4 n.ABEL n.ABEL.Bonf n.ABEL.adj n.Molins
» 20 20 10 18 24 18 22
» 30 40 20 34 44 42 42
» 40 66 34 30 38 32 36
» 50 98 50 28 34 28 32
» Try the functions pa.ABE() and pa.scABE() of PowerTOST.

» The plots in the slide are all for ABEL. A comparison of ABE and the EMA’s (unadjusted) ABEL:
»
» [image]

»
» At 30% sample sizes are 40 and 34, at 40% 68 and 30.
»
» Hhm, not sure what you mean.

I just would like to say that it has no sense to conduct ABEL/RABE trials if the CV is assumed around 30% because, in order to control TIE, we have to increase the sample size to around that of usual ABE trials. It violates GCP principles in this case and invalidates the ABEL/RABE approach (subjects are subjected to unnecessary risks in the ABEL/RABE trials). And it very complicates the matter. Basically, when should we consider an ABEL/RABE trial?

Best regards

It also seems that when we wish to control TIE the sample size will be around 50 (worst scenario + dropout rate) in almost every case (usually little known about reference withindividual variability) of the ABEL/RABE. But I have rarely seen such trials.

Regards

Edit: Merged with a later (now deleted) post. You can edit your posts for 24 hours. [Helmut]

Complete thread:

Statistical evaluation and BE hypotheses in full replicate design Elena777 2020-01-28 07:02 [RSABE / ABEL]
- Inflation of the TIE as well Helmut 2020-01-29 15:38
  - Inflation of the TIE as well Elena777 2020-01-29 20:01
    - Tricky… Helmut 2020-01-30 12:07
      - Tricky… Mikalai 2020-01-30 13:08
        
        Terrible… Helmut 2020-01-30 15:09
        
        Tricky… Mikalai 2020-01-30 16:02
        
        Deep shit Helmut 2020-01-30 16:59
        
        Deep shit Mikalai 2020-01-30 18:39
        
        Deep shit Mikalai 2020-01-30 19:31
        Deep shit Helmut 2020-01-30 20:07
        
        Deep shit Mikalai 2020-01-31 11:14
        
        Deep shit Helmut 2020-01-31 14:00
        
        Deep shitMikalai 2020-01-31 16:07
        
        Flawed evaluation accepted Helmut 2020-01-31 12:19
        
        Flawed evaluation accepted Mikalai 2020-01-31 12:40
        
        Flawed evaluation accepted Helmut 2020-01-31 14:17
        
        Flawed evaluation accepted Mikalai 2020-01-31 16:41
        
        Flawed approach even if accepted 😡 Helmut 2020-01-31 20:28
        
        Flawed approach even if accepted 😡 Mikalai 2020-02-01 16:18
        
        misunderstanding mittyri 2020-02-01 21:34
        
        misunderstanding Mikalai 2020-02-06 13:41
        
        misunderstanding mittyri 2020-02-06 16:23
        
        The globe is flat! d_labes 2020-02-05 19:16
      - Tricky… wienui 2020-01-30 18:53
        
        Tricky… Helmut 2020-01-30 19:18
        
        Tricky… wienui 2020-02-03 07:10
        
        ABE vs. ABEL Helmut 2020-02-03 12:25
        
        zigzag d_labes 2020-02-05 18:53
        
        zigzag Helmut 2020-02-05 19:46
        
        zigzag Mikalai 2020-02-06 11:38
        
        helter-skelter Helmut 2020-02-06 20:12
        
        helter-skelter Mikalai 2020-02-10 16:10
  - Inflation of the TIE as well zizou 2020-02-01 17:00
    - Inflation of the TIE as well nobody 2020-02-01 23:30
  - Inflation of the TIE as well Elena777 2020-03-10 19:28
    - Fishing in the dark Helmut 2020-03-10 21:06
- Statistical evaluation and BE hypotheses in full replicate design nobody 2020-02-03 15:07
  - TIE, repeat once more please... Astea 2020-04-02 12:41