Re: How to calculate confidence interval (CI) and prediction interval (PI) of individual prediction (IPRED) in NONMEM
Hi,
I have a question on ADVAN5 and ADVAN7 related to dose event record. This is a general linear model.
Can these two models allow multiple doses in compartment 1 and 3, simultaneously?
Best regards,
Sam Liao
Pharmax Research, Inc.
Quoted reply history
On 7/19/2018 11:50 AM, Bauer, Robert wrote:
> NONMEM 7.4 provides a straight-forward means of evaluating the standard error of IPRED and other table outputted parameters, by use of the option $TABLE … VARCALC=1. Please see nm743.pdf for more information on this, located at
>
> https://nonmem.iconplc.com/nonmem743
>
> Robert J. Bauer, Ph.D.
>
> Senior Director
>
> Pharmacometrics R&D
>
> ICON Early Phase
>
> 820 W. Diamond Avenue
>
> Suite 100
>
> Gaithersburg, MD 20878
>
> Office: (215) 616-6428
>
> Mobile: (925) 286-0769
>
> [email protected] <mailto:[email protected]>
>
> www.iconplc.com http://www.iconplc.com/
>
> *From:* [email protected] [ mailto: [email protected] ] *On Behalf Of *Kyun-Seop Bae
>
> *Sent:* Wednesday, July 18, 2018 8:56 PM
> *To:* [email protected]
>
> *Subject:* [NMusers] How to calculate confidence interval (CI) and prediction interval (PI) of individual prediction (IPRED) in NONMEM
>
> Dear NMusers,
>
> Someone (several months ago via email) asked me how to calculate a confidence interval and prediction interval for individual prediction using R (might be with my “wnl" package”).
>
> At that time, I suggested the delta method for a confidence interval and simulation for prediction interval like visual predictive check (VPC).
>
> He/She then asked me how about using NONMEM script in p220 (for the prediction interval) and p221 (for the confidence interval) of Ette and William's ‘Pharmacometrics: The Science of Quantitative Pharmacology’(2007), when I could not answer about that and still recommended to use simulation technique.
>
> Now I can answer a little more about how to calculate those (although somewhat naïve way) in NONMEM (maybe in older versions only).
>
> NONMEM code in p220 should be corrected like the following;
>
> “VARCP = 2*G(1,1)*G(2,1)*OMEGAF(1,2) + VARCP
>
> “VARCP = 2*G(1,1)*G(3,1)*OMEGAF(1,3) + VARCP
>
> “VARCP = 2*G(2,1)*G(3,1)*OMEGAF(2,3) + VARCP
>
> “VARCP = VARCP + IPRED**2*SIGMAF(1,1) + VARCP*SIGMAF(1,1) + SIGMAF(2,2)
>
> And, NONMEM code in p221 should be corrected like the following;
>
> “VARCP = 2*G(1,1)*G(2,1)*OMEGAF(1,2) + VARCP
>
> “VARCP = 2*G(1,1)*G(3,1)*OMEGAF(1,3) + VARCP
>
> “VARCP = 2*G(1,1)*G(4,1)*OMEGAF(1,4) + VARCP
>
> “VARCP = 2*G(2,1)*G(3,1)*OMEGAF(2,3) + VARCP
>
> “VARCP = 2*G(2,1)*G(4,1)*OMEGAF(2,4) + VARCP
>
> “VARCP = 2*G(3,1)*G(4,1)*OMEGAF(3,4) + VARCP
>
> One of the references for the biggest different line is p180 of <Mood AM, Graybill F, Boes DC. Introduction to the theory of statistics. 3e. 1974>.
>
> Sincerely,
>
> Kyun-Seop Bae MD PhD
>
> Professor
>
> Department of Clinical Pharmacology and Therapeutics
>
> Asan Medical Center, University of Ulsan, Republic of Korea
>
>