10-30-2014 11:39 AM
I am having doubt in Estimate Statement in proc mixed procedure.
ESTIMATE 'TEST VS REFERENCE' TRT 1 -1;
When want to use 1 -1 or -1 1,
TRT (T- Test and R- Reference) code as
TRT -1 1 to compare test with reference. my results are matching, but for TRT (A- Test and B- Reference) I used same code but my results are not matching if we use 1 -1 then my answer is matching.
What logic is behind this?
10-30-2014 01:21 PM
SAS Proc mixed Code,
PROC MIXED DATA = PK;
CLASSES SEQUENCE SUBJECT PERIOD TRT;
MODEL LN_CMAX = SEQUENCE PERIOD TRT / ddfm = satterth;
RANDOM TRT / type = fa0(2) sub = SUBJECT G;
REPEATED/grp = TRT sub = SUBJECT;
LSMEANS TRT / cl alpha = 0.05 diff;
ESTIMATE 'T vs. R' TRT -1 1/cl alpha = 0.1;
ODS OUTPUT ESTIMATES = CMAXUNSCL ( keep = lower upper );
ODS OUTPUT LSMEANS = CMAXLSM
TESTS3 = CMAXTYPE3
COVPARMS = CMAXCPARMS
DIFFS = CMAXDIFF;
90 % CI is not matching CI=exp(lower);
10-30-2014 01:49 PM
That really doesn't help. We can't see what the results are, we don't see what doesn't match, you need to SHOW US the non-matching output. And you also need to show us the two versions of the code that gives the non-matching output.
10-30-2014 03:46 PM
So the 90% CI in the ESTIMATE block does not match 'lower' and 'upper' in the output dataset? That seems really unlikely, since it is an ODS dataset..
That particular piece of code has some interesting tricks going on, so it really makes a difference when you say things don't match that we be able to duplicate what you see.