Origin of SAS code? [Software]
❝ in the following SAS code
where does this code come from? It’s not the standard one recommended by the FDA here and there.
model AUCT=sequence period treat/DDFM=kr;
I would suggest to use
DDFM=SATTER(as the FDA recommends). The default of
DDFM=KRuses the observed information matrix (
SCORING=0) as does jmp. You may run into troubles if your study is re-evaluated in other software which uses the expected information matrix (e.g., Stata, R-package
replicateBE). In SAS you can get the expected information matrix by setting
random treat/type=CSH subject=subject G;
❝ In the Random statement
TYPE=CSH could possibly be replaced by
Acc. to the FDA’s guidance, Appendix E:
In the Random statement,
TYPE=FA0(2) could possibly be replaced by
FA(1) is not the same as
FA(q) = factor analytic and
FA0(q)= no diagonal factor analytic.
If this is a full replicate design, I would follow the FDA’s recommendation and use
However, in the stupid partial replicate designs (TRR|RTR|RRT or TRR|RTR) the optimizer may fail to converge since the model is over-specified (T not repeated). Then you’ve performed a study and don’t get a result cause SAS shows you the finger.* I suggest to specify
FA0(1)instead. State that already in the SAP.
- If you are lucky SAS throws only a warning.
Convergence criteria met but final hessian is not positive definite.
But if Murphy’s law hits:
WARNING: Did not converge.
WARNING: Output 'Estimates' was not created.
Dif-tor heh smusma 🖖🏼 Довге життя Україна!
The quality of responses received is directly proportional to the quality of the question asked. 🚮
- SAS code for ABE Mahmoud 2020-07-03 14:09 [Software]