You seem to have count data for your DV

See the attachments for what you should do

Good luck, David Booth

Dear Lisandra Almeida de Oliveira,

I think your question is how to add baseline data for your analysis, if I got it. It's a common issue for repeatedly measured data to treat a data values and variables very well before analysis. It may require a loop code in R. But, your analysis tool is now STATA. Hence, I think it's better to separate the baseline information or observation values manually. Thus, there may be a cluster of observations for each subjects identified by the corresponding ID and select only the first observation for all subjects, then save the data in a separate file name. After all you can use your syntax for analysis or you can manually use the STATA analysis tools from the drop menu.

Dear David Booth,

Thank you for your answer!

I really appreciate it!

Best!

Dear Getachew Mekiso Tekle,

Thank you for your answer!

I agree with you! I thought in doing it manually, but I was hoping somebody could help me with doing that automatically on Stata!

I ended up creating a new dataset!

Thank you so much!

Best,

Lisandra Almeida

Dear Lisandra Almeida,

If I would be your help, my email: [email protected].

Good luck!