Hi, for my cumulative dataset (European Social Survey 2002-2018) I have a variable which measures if a respondent is a parent or not (bthcld).
However, for the third round of my dataset (ESS 2006), the question comes in two forms (if the respondent is a parent (bthcld)) and (if the respondent has any children living at home (chldhm)).

To be clear, I want to keep the variable. But how can I drop the observations of the variable (bthcld) for the third round of my dataset? (essround 3) (corresponds to my time-identifier variable - essrounds).
What I've tried to do is something in the lines of:
Code:
 drop if bthcld == essround 3
which creates an invalid syntax (I've included it to give an idea of what I'm trying to do).

Kind regards