Re: Inclusion of covariates and model improvement

From: Leonid Gibiansky leonidg@metrumrg.com Subject: Re: [NMusers] Inclusion of covariates and model improvement Date: Thu, 20 Oct 2005 00:47:27 -0400 Hi Toufigh, This is the black magic that I practice when I have time :) Actually, this is the standard way to include weight into the model (with the exception of strict allometric scaling approach that assumes that THETA(2) should always be equal to 1). This model allows for not-so-steep increase of VC with weight. 70 is the mean-median value; normalization should not change the model but simplifies the interpretation (THETA(1) is the VC of a typical 70-kg patient). I am not 100% sure, but normalization may also influence the precision of estimation. Leonid