4 replies to this topic

[Michael Kong]

Hi all,

 

I am using nonparametric superposition to simulate steady state (bid) from 12 hr single dose data. I would like to simulate the impact of missed doses on steady state levels. I have set up my project to simulate over 84 hrs. In the dosing tab I have time from 0 to 84 hrs every 12 hrs and my output time range is 0 to 84 hrs. My problem is that the simulation fails if I simulate a missed dose (dose=0) at 48 hrs (or at any other time). The simulation works if I impute the missed dose to be some low positive number relative to the actual dose (eg: 0.01).

Can someone advise if this is the best approach (or recommend an alternate approach to do this)?

 

Thanks,

Mike

[Samer Mouksassi]

We will have to check why it does not work with a zero. I think entering a very small value is a good workaround for now.

Nonparametric superposition is limited and has some assumptions.

A better way would be to develop a PK model and conduct the simulations and dosing regimens you want.

Samer

[Simon Davis]

Mike, I normally delete the line of the missed dose from my dosing schedule (using the black X), however I just tested it in 6.3 and a zero will also work fine, for me a t least ;0).

Is it possible you can post the project either here or email support as I suspect there is something else causing the problem you mention.

Simon

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[Michael Kong]

Sorry for the delay in responding Simon. In my example, if I check off 'Repeat every xx time units' where xx=84, then it will give me the error. Since my output range is only 84hrs, there's no need to check this option. With this option unchecked, it will handle zero just fine.

Thanks,

Mike

[Simon Davis]

OK - seems to have been a data input conflict, NPS can get a bit finicky over what it sees as inconsistencies e.g. repeating dosing beyond requested sampling time

 

  Simon