Bioequivalence and Bioavailability Forum

Dear all,

sitting here and wondering once again about an old and often pondered problem:

One of the things to be prepared in BE studies is the synoptic plot of mean concentrations versus time for the formulations under study.

I pondering especially about dealing with entries <LLOQ (or whatever your entry for values below lower limit of quantitation is).

So my question is to you:

• Do you treat them as missing?
  
• Do you assign a special value to it (f.i. zero, LLOQ/2 or what else)?

Second part:

• Which mean function do you use? Arithmetic, geometric, median? And why?

To expose my method:
I use the common arithmetic mean and consider entries <LLOQ as zero.
But I have no rationale for that other than simplicity.

Thus looking forward to your reasoning.