RE: NONMEM error
Hi Dennis,
One other idea that can help if all measures are BQL is to use a reset
record or reset and dose (EVID 3 or 4) on the subsequent doses. That way,
the integrator will be restarted for those participants and may help.
Thanks,
Bill
Quoted reply history
-----Original Message-----
From: [email protected] <[email protected]> On Behalf
Of Leonid Gibiansky
Sent: Thursday, December 5, 2024 3:14 PM
To: Dennis Fisher <[email protected]>; [email protected]
Subject: Re: [NMusers] NONMEM error
Are there any measurements that are not BQLs and that are more than 24 hrs
from the last dose? What is the residual error ? Combined error (rather than
proportional or exponential) may help. Random effect on residual error is
very helpful to identify aberrant subjects/observations. $ABBREV PROTECT
helps sometimes. NOHABORT (with
H) can help but it is dangerous, so it can be used for debugging, but not
for the final models.
I would look on the data with large WRES (after the FO run) to see whether
any of the observations are so far off that Nonmem cannot fit them and
crashes.
Thank you
Leonid
On 12/5/2024 2:33 PM, Dennis Fisher wrote:
> Colleagues
>
> I have encountered a problem during NONMEM execution.
>
> Most subjects are dosed daily but a small number of subjects have
> large intervals (> 30 days) between successive doses.
> For subjects dosed daily, concentrations 24 hours after a dose are BQL
> and there is no evidence of accumulation.
>
> For the problem subjects, NONMEM either:
> 1. aborts (despite a NOABORT option) with an error message at the
> first dose after the lengthy gap 2. or sends the following error
> message:
>
> 0PRED EXIT CODE = 1
> 0INDIVIDUAL NO. 103 ID= 3.11040000000000E+04
> (WITHIN-INDIVIDUAL) DATA REC NO. 56
> THETA=
> 1.66E+02 1.15E-01 2.95E+01 1.81E+01 4.33E+01 3.01E+02
> 8.26E+00 0.00E+00 1.00E+00 0.00E+00
> 0.00E+00 1.00E+00 1.00E+00 1.00E+00 1.00E+00 1.00E+00
> 1.00E+00
> OCCURS DURING SEARCH FOR ETA AT INITIAL VALUE, ETA=0
> NUMERICAL DIFFICULTIES WITH INTEGRATION ROUTINE.
> MAXIMUM NO. OF EVALUATIONS OF DIFFERENTIAL EQUATIONS, 1000000,
> EXCEEDED.
>
> The error occurs with METHOD=1 but NOT with METHOD=0.
>
> For one subject in whom doses were administered on Days 1, 30, and 60
> (followed by daily dosing), I deleted the first two dosing records and
> the error no longer occurs with METHOD=1. I speculate that the error
> might relate to the predicted concentration becoming Infinitesimally
> small after a lengthy interval between doses, However, I have no idea
> if this is the explanation. And I am reluctant to change the dataset
> so I seek other solutions.
>
> Any ideas as to an explanation or a work-around?
>
> Dennis
>
>
> Dennis Fisher MD
> P < (The "P Less Than" Company)
> Phone / Fax: 1-866-PLessThan (1-866-753-7784) www.PLessThan.com
>