Bioequivalence and Bioavailability Forum

The mysterious ρ -between or within studies [General Statistics]

posted by Astea – Russia, 2018-02-11 18:34 (2264 d 08:05 ago) – Posting: # 18397
Views: 15,472

Dear Detlew!

Thank you very much for the explanation! Now I've got it! (Yes, multitasks harm..)

So, for ρ=0.8 I get now

type1error.2TOST(CV=c(0.3, 0.25), n=122, theta1=c(0.8, 0.9),

                 theta2=c(1.25, 1/0.9), rho=0.8, details=TRUE)

1e+06 simulations. Time consumed (secs)

   user  system elapsed 

 979.75   95.18 1115.72 

  Intersection null P(Type I Error) theta0 #1 theta0 #2

1      H_A01 n H_Ca        0.048904 0.8000000  0.953047

2      H_A02 n H_Ca        0.049193 1.2500000  1.056122

3      H_Aa n H_C01        0.049620 0.9709781  0.900000

4      H_Aa n H_C02        0.050024 1.0000000  1.111111

5     H_A01 n H_C01        0.024479 0.8000000  0.900000

6     H_A01 n H_C02        0.000000 0.8000000  1.111111

7     H_A02 n H_C01        0.000000 1.2500000  0.900000

8     H_A02 n H_C02        0.024451 1.2500000  1.111111

and inflation at 0.050024

As I understand estimated from several datasets ρ is "between studies" ρ while in Power2TOST we need to use "within studies ρ". But it may be interesting while discussing multicomponent drugs. Especially question may arise for two components, when one of them is HVD while other is not and different approaches or CI limits involved (like telmisartan+amlodipine).
The intermediate question is mentioned situation about parent drug and its metabolite - logically, the correlation for the parameters of parent drug and its metabolite should be stronger than for two different drugs tested on the same population?

Dear Helmut!
Do I understand correctly that in your latest code you exployed all AUC and Cmax individual data for each study in order to estimate "within rho"?

—
"Being in minority, even a minority of one, did not make you mad"

Complete thread:

Power and type I adjustment for 222BE when several PK prams considered Louis52 2018-02-07 21:04
- Power and type I adjustment for 222BE when several PK prams considered ElMaestro 2018-02-07 22:37
- Power of two combined TOST d_labes 2018-02-08 14:12
  - The mysterious ρ Helmut 2018-02-08 21:40
    - ρ ρ ρ your boat ElMaestro 2018-02-09 09:58
      - ρ ρ ρ your boat Helmut 2018-02-09 19:20
    - ...and a bonus question ElMaestro 2018-02-09 11:32
      - ...and a bonus question Helmut 2018-02-09 19:43
        
        If u see a BEar don't forget to R oaρ Astea 2018-02-09 20:47
        
        package install failed d_labes 2018-02-11 13:23
    - The mysterious ρ -between or within studies d_labes 2018-02-11 15:57
      - The mysterious ρ -between or within studies Helmut 2018-02-11 17:31
        
        The mysterious ρ -between or within studies d_labes 2018-02-11 19:21
        
        The mysterious ρ within studies Helmut 2018-02-11 22:44
        
        The mysterious ρ within studies nobody 2018-02-12 09:08
      - The mysterious ρ -between or within studiesAstea 2018-02-11 17:34
        
        The mysterious ρ -between or within studies d_labes 2018-02-11 19:36
        The mysterious ρ within studies Helmut 2018-02-11 22:48
- Power and type I adjustment for 222BE when several PK prams considered ElMaestro 2018-02-11 18:43
  - Power and type I adjustment for 222BE when several PK prams considered nobody 2018-02-12 09:10
    - reminds me of something ElMaestro 2018-02-12 09:18
      - reminds me of something nobody 2018-02-12 09:38
        
        Hammer to fall Astea 2018-02-12 18:37
        
        Put the sickle to the corn Helmut 2018-02-13 01:37
        
        Put the sickle to the corn Astea 2018-02-13 08:27
        
        Put the sickle to the corn Helmut 2018-02-13 12:45
        
        Put the sickle to the corn Relaxation 2018-02-13 10:37
        
        multiple units, lag-times Helmut 2018-02-13 13:31

The mysterious ρ -between or within studies [General Sta­tis­tics]

Complete thread:

The mysterious ρ -between or within studies [General Statistics]