Is covariate search limit on covariate number?

Hi All, Today I upgraded to NLME 1.1 hoping that all my problems with 1.0 would be solved. And indeed that is how it seems until I got to the covariate search. While the covariate search in 1.0 seemed to work fine, I can’t get the covariate search in 1.1 to look at all of the covariates. I have 5 covariates (one categorical) and I am looking for effects on V and Cl in a 2 compartment Full model with multiplicative residual error. I am running FOCE ELS. Do I need to switch to a different engine? Is there a limit to the number of covariate vs thetas and have I exceeded it. It was working fine with version 1.0 so I did not anticipate a problem with 1.1. I am using the closed from option since I only have sampling from the central compartment, no nonlinearity, and no covariates changed over the 2 hour study period. I was planning to get a bootstrap analysis running overnight but it just isn’t going to happen. Any help would be appreciated. Kind regards, Jim

Dear Jim, We are looking into this. For the meantime, my suggestion would be to look at the covariate plots and the covariate box plots from the base model, and consider only the covariates that seem to have an effect on the etas for the stepwise covariate search. Best regards, Emily