NonMem and EVID=2

Hello everybody,

In order to obtain predicted values in a PopPK analysis without covariates at points in time with no actual values I have inserted extra rows indicated with EVID=2. The covariance step is completed when including these extra rows and precision of the parameter estimates are adequate. When omitting the extra rows {IGNORE=(EVID.EQ.2)}, I get exactly the same parameter estimates, the covariace step can be completed with some difficulty, but precision of the parameter estimates are now inadequate. I use METHOD=1 and just like Ahmed Abbas Suleiman experienced (, my outcome did not differ between the two conditions when setting METHOD=0. I saw that William Denney has responded to a similar question in 2016 (

I cannot see any response to Ahmed’s comment; do you Bill or somebody else have any idea why the outcomes differ with METHOD=1 but not with METHOD=0 in NonMem when including extra rows in the data set?

Thank you in advance and kind regards,