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RE: [NMusers] Lognormal survival in NONMEM?

From: Rik Schoemaker <rik.schoemaker_at_occams.com>
Date: Fri, 30 Aug 2019 09:04:31 +0000

Dear Siv, Jonathan, and Jakob,

Thank you all for your wonderful and insightful replies; great to see the NONMEM forum alive and kicking ūüėä. Now I will try and implement to see if this solves my issues!

Kind regards,

Rik



From: owner-nmusers_at_globomaxnm.com <owner-nmusers_at_globomaxnm.com> On Behalf Of Jakob Ribbing
Sent: 29 August 2019 16:18
To: nmusers_at_globomaxnm.com
Subject: Re: [NMusers] Lognormal survival in NONMEM?

Dear Rik,

There are very nice code examples (for NONMEM) in this poster-material from Nyberg et al.:
https://www.page-meeting.org/pdf_assets/404-Poster_PAGE%20_2014_tte_sim_joakim_nyberg_with_code.pdf

These include the log-normal distribution, as well as Gompertz and Weibull.

Best regards

Jakob



Jakob Ribbing, Ph.D.

Senior Consultant, Pharmetheus AB



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On 29 Aug 2019, at 15:33, Rik Schoemaker <rik.schoemaker_at_occams.com<mailto:rik.schoemaker_at_occams.com>> wrote:

Dear all,

Playing with repeated time to event models, I run into the issue that simple diagnostics for a single time to event outcome suggest that constant hazard and Weibull models are not very appropriate. The lognormal model seems to provide a very nice fit; compared to a constant hazard, the hazard is suggested to be higher in the beginning and then significantly lower at later times.

I have not seen any implementations online: does anyone know if the lognormal survival function can be implemented in NONMEM, and/or can anyone suggest alternative approaches? Some time-varying function to modify the hazard?

Any and all suggestions appreciated!

Kind regards,

Rik



Rik Schoemaker, PhD
Occams Coöperatie U.A.
Malandolaan 10
1187 HE Amstelveen
The Netherlands
www.occams.com<http://www.occams.com/>
+31 20 441 6410
rik.schoemaker_at_occams.com<mailto:rik.schoemaker_at_occams.com>

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Received on Fri Aug 30 2019 - 05:04:31 EDT

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