RE: Significance?

From: "Wang, Bing" Subject: RE: [NMusers] Significance? Date: Mon, 15 Apr 2002 11:59:21 -0700 Chyi-Hung, Some questions/recommendations: 1. When you separate the two CL, (CL1 for Group A and CL2 for Group B), are these two CL estimates greatly different? (Although you mentioned OBJ did not change much, what about actual CL estimates?) 2. Try to separate the residual errors for Groups A and B in the $ERROR block. If you do so, how different are those ERR estimates? Is it possible that one group could be better described by a model other than the 3-c model...? Do you expect the PK in Groups A and B to be the same? 3. If PK is linear, the modeling shall give results fairly close to the NC analysis. Could the model be over parameterized somehow? 4. It may help to re-check the coding, and to confirm the comparison of OBJs is fair: FOCE vs FOCE, but not FO vs FOCE... 5. If overall goodness-of-fit graphs look OK and the OBJ change says nothing significant, and noncompartmental analysis (AUCs) did not show a trend between Groups A and B, continue your modeling without considering such group difference. Once you reach the final model, in your model validation step, separate the CLs to see if it makes any difference there... Regards. Bing Wang Amgen *******