I’m running a nationally representative study, aiming to recruit 1500 participants in total. As the survey is quite complex, I ran an initial study with just 500 participants, with the idea of then running a duplicate study and recruiting the next 1000 once I knew that everything was working well with the data collection. Do you know if it is possible to run a nationally representative sample and also include the prescreener to exclude participants from previous studies? I can’t seem to get both options to work at once.
Many thanks and best wishes,