Bioequivalence and Bioavailability Forum • PTF is another story

PTF is another story [NCA / SHAM]

posted by d_labes – Berlin, Germany, 2009-12-03 17:17 (5631 d 09:22 ago) – Posting: # 4424
Views: 11,720

Dear Helmut!

Answered to hasty, so I got not your second point.

❝ So what was your primary target in that study? I would say that the high variability of %PTF in that study was bad luck. In my experience as an aggregate metric it 'behaves' quite nicely in most cases.

The study was long ago. So I don't remember exactly what was going on.
But I have occasionally found that the variability of PTF was high if PTF was low. In a additive model this makes immediately sense:
CV=sd/Mean
is increasing if the mean is decreasing.

BTW: For me it's questionable if a logarithmic transformation could and should be applied for this metric (also I do because of regulators).

—
Regards,

Detlew

Complete thread:

Statistics in multiple dose study ratnakar1811 2009-12-01 11:09
- Statistics in multiple dose study Helmut 2009-12-02 00:20
  - Statistics in multiple dose study ratnakar1811 2009-12-03 07:36
    - Statistics in multiple dose study Helmut 2009-12-03 14:53
      - Statistics in multiple dose study ratnakar1811 2009-12-04 08:21
  - Metrics for multiple profiles d_labes 2009-12-03 08:58
    - Metrics for multiple profiles Helmut 2009-12-03 15:50
      - Metrics for multiple profiles d_labes 2009-12-03 16:02
        
        Metrics for multiple profiles Helmut 2009-12-03 16:11
      - PTF is another storyd_labes 2009-12-03 16:17
        
        PTF is another story Helmut 2009-12-03 16:42
        
        the flatter is better? d_labes 2009-12-04 08:46
        
        Biopharmaceutical history Helmut 2009-12-04 12:35