least square mean calculation [General Sta­tis­tics]

posted by bvoggu – 2010-08-19 11:24 (5372 d 20:41 ago) – Posting: # 5806
Views: 9,760

(edited on 2010-08-20 07:58)

Dear Helmut,
Thank you very much for immediate response
I did calculation for least square mean of test and reference product in a 2X2 cross over study (TR Vs RT), but i am getting correct values for Cmax and AUCt only, but not for AUCinf. Please check with the following data if possible...

SubID Period Treatment Sequence  AUCt     AUCinf
XR03    1       R         RT     7833     7926.2
XR04    1       R         RT     7622.2   7730.3
XR07    1       R         RT     6477.7   6546.2
XR10    1       R         RT    10528.1  10682.1
XR11    1       R         RT    10968.6  11269.8
XR14    1       R         RT     8472.2   8535.6
XR16    1       R         RT    11593.9  11786.0
XR18    1       R         RT     7353.6   7473.4
XR20    1       R         RT     6090.6   6137.7
XR03    2       T         RT     6484.3   6601.6
XR04    2       T         RT     8587.1   8739.8
XR07    2       T         RT     4201.9   4262.8
XR10    2       T         RT     9566.9   9741.1
XR11    2       T         RT    12203.3  12404.6
XR14    2       T         RT     8495.7   8575.0
XR16    2       T         RT    10392.5  10554.7
XR18    2       T         RT     7859.7   8021.7
XR20    2       T         RT     7463.3   7549.4
XR01    2       R         TR     9982.6  10101.9
XR02    2       R         TR     6774     6879.6
XR05    2       R         TR     6065.1   6247.4
XR09    2       R         TR     7789.5   7913.9
XR13    2       R         TR     6253.9   6390.1
XR15    2       R         TR     5965.3   6056.8
XR17    2       R         TR     5593.2   5682.8
XR01    1       T         TR     9902.2  10044.0
XR02    1       T         TR     6684     6906.9
XR05    1       T         TR     5813.7   5903.5
XR09    1       T         TR     7975     8116.1
XR13    1       T         TR     6925     7026.4
XR15    1       T         TR     5995.3   6075.5
XR17    1       T         TR     6094.7   6191.3


Calculation according to mine is AUCt-LSM 8.919 (T), 8.927 (R)
Calculation according to SAS default programme for AUCt-LSM 8.919 (T), 8.927(R)
But for AUCinf my results are-8.929 (R) and 8.974 (T)
But SAS programme results are-8.942 (R) and 8.936 (T)
I am not getting why these are different :confused:
excuse me for such a lengthy data....
Please clarify me that a balanced design is nothing but number of sub facing TR is equal to number of sub facing RT right?
what is the formula for calculation of standard error of difference?

I am getting these difference bcz of excel, Please clarify SAS and Excel results are different to some extent right? and please provide me calculation upto LSM with one of our's members formula
(mean_seq1+mean_seq2)/2 for balanced design or (mean_seq1*n1)+(mean_seq2*n2)}/(n1+n2) for unbalanced design (I thought that second formula is best because our data is unbalanced). But I am getting result only with first formula not with second. Please clarify this.

Regards,
Bharat

Complete thread:

UA Flag
Activity
 Admin contact
23,424 posts in 4,927 threads, 1,669 registered users;
70 visitors (0 registered, 70 guests [including 6 identified bots]).
Forum time: 08:05 CEST (Europe/Vienna)

My doctor gave me six months to live,
but when I couldn’t pay the bill
he gave me six months more.    Walter Matthau

The Bioequivalence and Bioavailability Forum is hosted by
BEBAC Ing. Helmut Schütz
HTML5