Bioequivalence and Bioavailability Forum • Sample size/power for PD BE study 3-way crossover

Sample size/power for PD BE study 3-way crossover [Power / Sample Size]

posted by jdetlor – 2011-04-01 23:51 (5563 d 15:33 ago) – Posting: # 6853
Views: 10,235

❝ Let's say your have an idea of variability within and between (i guess one could start out with gaussian variability but everything is possibly, especially since the FDA does not like parametrics for this analysis), and some guesses for ED50 and f etc. How do you incorporate the relevant variabilities to simulate the data?

The between and within variabilites are incorporated to the Emax model the same way they are to the linear model. The difference is instead of a response variable summing up effects linearly, the between and within subject variabilty are added to the non-linear Emax model. Categorical index variables for treatment and dose are also coded. It is assumed the errors are normal, which may not be a terrible assumption since they are modeled as such.

So for example, when creating the response variable for the test treatment at dose 0, you would sum your Eo parameter, your between-subject variability, and your within-subject variability (as the non-linear portion is 0). Continuing on at non-zero dose levels, the summation for the response variable would be the Eo parameter, your between-subject variability, your non-linear function (using Emax, 'f', ED50 parameters), and your within-subject variability.

Complete thread:

Sample size/power for PD BE study 3-way crossover Coja66 2011-03-28 14:22
- Sample size/power for PD BE study 3-way crossover Helmut 2011-03-29 14:34
  - Sample size/power for PD BE study 3-way crossover Coja66 2011-03-29 15:31
    - Sample size/power for PD BE study 3-way crossover Dr_Dan 2011-03-30 10:13
      - Sample size/power for PD BE study 3-way crossover Coja66 2011-03-30 11:36
        
        Sample size/power for PD BE study 3-way crossover ElMaestro 2011-03-30 13:48
        
        Off topic (W.H.) Helmut 2011-03-30 13:59
        
        Off topic (W.H.) ElMaestro 2011-03-30 14:54
        
        Off topic (W.H.) Helmut 2011-03-30 15:05
        
        Sample size/power for PD BE study 3-way crossover ElMaestro 2011-03-31 19:55
        
        Sample size/power for PD BE study 3-way crossover jdetlor 2011-04-01 15:52
        
        Sample size/power for PD BE study 3-way crossover ElMaestro 2011-04-01 16:19
        
        Sample size/power for PD BE study 3-way crossover jdetlor 2011-04-01 16:56
        
        Sample size/power for PD BE study 3-way crossover ElMaestro 2011-04-01 17:14
        
        Sample size/power for PD BE study 3-way crossoverjdetlor 2011-04-01 21:51