Bioequivalence and Bioavailability Forum

Dear all,

As promised , below you'll find an SPSS code to analyze a standard 2x2x2 crossover BE study. In your data sheet, name your columns something like subject, period, sequence, treatment, Cmax, AUCt, AUCinf..., and fill in your data. In the treatment/formulation column test product should be coded 1 and reference 2; sequence 1=TR and 2=RT (as opposed to bear). ln Cmax can be automatically computed (if you'd like to do this in SPSS, column lnCmax will be added to your data sheet) by

COMPUTE lnCmax=LN(Cmax).
EXECUTE.

NCA is not included, so you have to compute your PK parameters first with e.g. bear, pksolver for M$ Excel, SAS or any other...

GLM
   lnCmax BY period sequence treatment subject
   /CONTRAST(treatment)=Simple
   /METHOD=SSTYPE(3)
   /INTERCEPT=INCLUDE
   /CRITERIA=ALPHA(.1)
   /PRINT=DESCRIPTIVE <--optional
   /DESIGN= subject within sequence period treatment sequence.

Include /RANDOM=subject to set subject as random factor (not recommended by the guideline). You may back-transform the results to obtain GMR PE and 90% CI. CVintra is obtained from the MSE, obviously. I have "validated" my SPSS results with SAS and bear.

Hope this may be useful to the very few that use SPSS in the BE/PK world