Bioequivalence and Bioavailability Forum • Imbalance or incomplete data, SASophylistic view

Imbalance or incomplete data, SASophylistic view [🇷 for BE/BA]

posted by ElMaestro – Denmark, 2008-10-29 10:27 (6075 d 19:40 ago) – Posting: # 2596
Views: 33,771

Dear Dlabes,

excellent input. I learn a lot from these discussions.
Allow me a little digression here....
I have never seen a *AHEM COUGH*ier for a 2,2,2-BE study in which subjects with missing period data are included in the study. In fact, it is sort of standard to simply specify that the analysis will be based on data from subjects completing both periods (in some cases it is even written as 'the first 28 completers' etc etc).
I think this stems from the fact that the EMEA has been challenged on missing data (missing periods can be considered such a thing, I guess). For this reason they produced some documents with guidance. That guidance implicitly deals mainly with progression-types of data (i.e. intended measurements of the degree of syphilis/parkinsonism/crohn/hemorrhoids/tuberculosis/survival/whatever at week 4, 8, 12, 16 after treatment initiation but data from week 12 goes missing, and how do you then do the Kaplan-Meier etc), but equivalence/non-inf. studies are not excluded per se. Among realistic alternatives, EMEA says, is imputation. Who can imagine imputation for missing 2,2,2-BE period data*? I think it is wise to simply rule those subjects out.
In R this would correspond to "na.omit" if my memory serves me correct.

Please, please more discussions of this type.
EM.

*: For example "Analyses that investigate missing data imbalance in all relevant factors and whether patients with and without missing values have different characteristics at baseline might also be conducted" and that sort of thinking [http://www.emea.europa.eu/pdfs/human/ewp/177699EN.pdf, under revision]

Complete thread:

bear v2.0.1 (upwards) cont'd yjlee168 2008-10-26 20:46 [🇷 for BE/BA]
- bear v2.0.1 (upwards) cont'd ElMaestro 2008-10-27 20:36
  - bear v2.0.1 (upwards) cont'd yjlee168 2008-10-28 08:59
    - bear v2.0.1 (upwards) cont'd ElMaestro 2008-10-28 09:49
      - Imbalance or incomplete data, SASophylistic view d_labes 2008-10-28 17:14
        
        Imbalance or incomplete data, SASophylistic view yjlee168 2008-10-29 07:36
        
        Incomplete cases d_labes 2008-10-29 09:24
        
        Incomplete cases yjlee168 2008-10-30 07:12
        
        Imbalance or incomplete data, SASophylistic viewElMaestro 2008-10-29 09:27
        
        Gold in discussion d_labes 2008-10-29 09:56
        
        Gold? Helmut 2008-10-29 13:03
        
        Imbalance or incomplete data, WinNonlin5.2.1 Helmut 2008-10-29 12:12
        
        Incomplete data, SAS9.2 d_labes 2008-10-29 16:38
        
        Missing values, imputation; separate study ElMaestro 2008-10-30 08:57
        Incomplete data, SAS9.2, DDF option residual d_labes 2008-10-30 15:54
        
        Never belief in any software you haven't written yourself Helmut 2008-10-30 16:30
        
        Imbalance or incomplete data, SASophylistic view yjlee168 2008-11-07 05:12
        
        Imbalance or incomplete data, SASophylistic view d_labes 2008-11-11 08:35
        
        Imbalance or incomplete data, SASophylistic view yjlee168 2008-11-11 08:54
        
        Imbalance or incomplete data, SASophylistic view d_labes 2008-11-11 13:13
        
        Imbalance or incomplete data, SASophylistic view yjlee168 2008-11-11 13:35
        
        Imbalance or incomplete data, SASophylistic view d_labes 2008-11-11 14:02
        
        Notification about new posts Helmut 2008-11-11 12:24
        
        Notification about new posts d_labes 2008-11-11 13:24
        
        3 Prerequisites for biostatistics Helmut 2008-11-11 13:39
        
        3 Prerequisites for biostatistics d_labes 2008-11-11 14:09