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RE: Lognormal survival in NONMEM?

From: Rik Schoemaker <rik.schoemaker>
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,


From: owner-nmusers rs
Sent: 29 August 2019 16:18
To: nmusers
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.:

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

Best regards


Jakob Ribbing, Ph.D.

Senior Consultant, Pharmetheus AB

Cell/Mobile: +46 (0)70 514 33 77

Jakob.Ribbing .Ribbing<>

Phone, Office: +46 (0)18 513 328

Uppsala Science Park, Dag Hammarskjölds väg 36B

SE-752 37 Uppsala, Sweden

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On 29 Aug 2019, at 15:33, Rik Schoemaker <rik.schoemaker

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 Schoemaker, PhD
Occams Coöperatie U.A.
Malandolaan 10
1187 HE Amstelveen
The Netherlands<>
+31 20 441 6410


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

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