PharmPK Discussion - Intrasubject CVs

• On 20 Nov 2007 at 15:24:29, "Katie Cussen" (katie.cussen.-at-.shandonclinic.ie) sent the message
  

  
  I would like to know how to calculate the intrasubject CV's for a 4-
  period 2-treatment replicate bioequivalence trial which I intend to
  analysis using proc mixed (SAS). I have analysed crossover
  bioequivalence trials before and used the formula 100%(e^MSE-1)^0.5 to
  calculate itrasubject CV where MSE is the mean square error. I got MSE
  this using proc glm. How should I calculate it this time? Do I
  calculate two separate ANOVA models for each treatment and use the
  different MSE's from each analysis to give separate intra-subject CV's
  or do I take a completly different approach?
  
  

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• On 20 Nov 2007 at 12:24:53, "Peter Bonate" (peter.bonate.at.gmail.com) sent the message
  

  
  Katie
  
  It's the same approach as with GLM.  The model would look like
  
  proc mixed;
      class subject trt period sequence;
      model lny = trt period sequence / ddfm=sat;
      random intercept / subject=subject(sequence);
  run; quit;
  
  When using Proc Mixed, the variance components are separated into
  between, which is called the intercept, and residual.  Use the
  residual variance to calculate intrasubject CV.
  
  pete bonate
  
  

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