Re: Covariate Models Using Weight

Date: Mon, 22 Nov 1999 13:42:12 -0600 From: James Gallo <JM_Gallo@fccc.edu> Subject: Re: Covariate Models Using Weight Steve, I disagree. I don't see how one can consider "PRE-Defined" models as mechanistic and "context-sensitive" [rather poor terminology] as empirical. Either type of model makes use of the same type of data [concentration-time or urine data and a mix of covairates], and it is only in how the final model shakes-out that one could attribute it to be 'mechanistic' or not. My concern is that the PRE-DEFINED models may be a priori applied as a surrogate for drug clearance when such application is unnecessary given a unique dataset for the drug of interest. I'd also be cautious of characterizing PRE-DEFINED models as being of "proven generality". Also, who cares if the so-called "context-sensitive" model is of "unknown generality" as long as it can most accurately predict clearance [for instance] for Drug X. Your last point that ultimately how one proceeds is up to the modeler is a good one. jim gallo