Bioequivalence and Bioavailability Forum • Sequential phenomena and some R code

Sequential phenomena and some R code [🇷 for BE/BA]

posted by yjlee168 – Kaohsiung, Taiwan, 2009-09-08 23:36 (5761 d 16:30 ago) – Posting: # 4173
Views: 8,846

Dear Elmaestro,

❝ [...]

❝ Given the nature of type I SS you will see that when Seq is included after Subj there is no (addition to) the SS, because of the good old "Subjects nested in Sequence". Thus the neglect. Hence you can try and include Seq before Subj - and then suddenly you have a Seq SS using type I SS. Think about it, it actually makes sense.

O.k., does this sequential phenomenon occur with SAS for type I SS calculation? The suggested SAS codes for 2x2x2 crossover is

PROC GLM DATA = KK;

CLASS SUBJ SEQ PER TRT;

MODEL LAUCT LAUCI LCMAX = SEQ SUBJ(SEQ) PER TRT; <--

TEST H = SEQ E=SUBJ(SEQ)/HTYPE=3 ETYPE=3;

ESTIMATE “A vs. B” TRT 1–1;

LSMEAN TRT;

RUN;

Looks like that we need to put seq before subj...

❝ The following elmaestrolophystic (probably bugged!) code illustrates it.

The codes works great and are quite illustrating. many thanks. :clap:

—
All the best,
-- Yung-jin Lee
bear v2.9.2:- created by Hsin-ya Lee & Yung-jin Lee
Kaohsiung, Taiwan https://www.pkpd168.com/bear
Download link (updated) -> here

Complete thread:

Imbalance + Type III SS = Tricky for the sequence evaluation ElMaestro 2009-09-07 21:16
- Imbalance + Type III SS = Tricky for the sequence evaluation yjlee168 2009-09-07 22:23
  - Imbalance + Type III SS = Tricky for the sequence evaluation ElMaestro 2009-09-08 16:49
    - Imbalance + Type III SS = Tricky for the sequence evaluation yjlee168 2009-09-08 20:02
      - Sequential phenomena and some R code ElMaestro 2009-09-08 20:28
        
        Sequential phenomena and some R codeyjlee168 2009-09-08 21:36
        
        Default in SAS ElMaestro 2009-09-08 21:43