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RegisterMIXED up and lost in design [General Statistics]
Dear KVitamin,
The Proc MIXED named in the FDA guidance "Statistical approaches ..." is recommended for replicate cross-over studies.
Here we are talking about the classical 2x2 cross-over.
Traditionally this is evaluated with Proc GLM if you use SAS for evaluation.
There are no such subjects in group T or group R! In a cross-over study each subject gets both treatments.
I strongly suggest that you study some textbooks about design and evaluation of bioequivalence studies before fiddling with a complex piece of software such as Proc MIXED.
A good starting point are Helmut's lectures. For a collection of books see here.
❝ I apply the SAS proc mixed because this procedure is assessed in FDA's guidance and I want to learn how works it (it is not simple).
The Proc MIXED named in the FDA guidance "Statistical approaches ..." is recommended for replicate cross-over studies.
Here we are talking about the classical 2x2 cross-over.
Traditionally this is evaluated with Proc GLM if you use SAS for evaluation.
❝ If I have a study data set as Helmuts data with 52 subjects and I calculate intra-CV and inter-CV based on your help, I will get results for all the subjects not for subjects in group T or subjects in group R, separately.
There are no such subjects in group T or group R! In a cross-over study each subject gets both treatments.
I strongly suggest that you study some textbooks about design and evaluation of bioequivalence studies before fiddling with a complex piece of software such as Proc MIXED.
A good starting point are Helmut's lectures. For a collection of books see here.
—
Regards,
Detlew
Regards,
Detlew
Complete thread:
- Intra subject CV% and Inter subject CV% Ravi 2009-04-11 08:35 [General Statistics]
![[Mix]](https://static.bebac.at/img/mix.png "open in Mix view")
- CV%-intra > CV%-inter Helmut 2009-04-11 13:19
- CV%-intra > CV%-inter Ravi 2009-04-14 06:01
- CV%-intra > CV%-inter kvitamin 2009-10-07 11:40
- Proc MIXED CV%-intra, CV%-inter d_labes 2009-10-07 13:05
- Proc MIXED CV%-intra, CV%-inter kvitamin 2009-10-07 16:15
- MIXED up and lost in designd_labes 2009-10-07 16:48
- MIXED up and lost in design kvitamin 2009-10-08 10:50
- 2x2, inter, intra, total or what d_labes 2009-10-08 13:41
- 2x2, inter, intra, total or what kvitamin 2009-10-09 11:05
- 2x2, inter, intra, total or what d_labes 2009-10-08 13:41
- MIXED up and lost in design kvitamin 2009-10-08 10:50
- MIXED up and lost in designd_labes 2009-10-07 16:48
- Proc MIXED CV%-intra, CV%-inter kvitamin 2009-10-07 16:15
- Proc MIXED CV%-intra, CV%-inter d_labes 2009-10-07 13:05
- CV%-intra > CV%-inter Helmut 2009-04-11 13:19
Ing. Helmut Schütz