The first study in the series
You don't have to do anything different when setting up your first study. You can follow the instructions in "Running an online study on Prolific Academic".
If you have multiple conditions make sure that you record the participant IDs of the participants who are assigned to each condition.
The follow up studies
When the first study is complete you can get the participant IDs of the relevant participants by clicking "Export Data" from your dashboard. You'll need these when setting up the rest of the studies in the series.
After filling out all the required information (as you would for any other study) click on the "Prescreening" tab. Scroll down to the "White List" section. Add the participant IDs of the participants you want to be able to take part in this follow up study.
ONLY these participants will be able to take part in this study. They will automatically be emailed with an invitation to take part.
If you have multiple conditions and if you want to keep these conditions consistent between studies you will need to set up a separate study for each condition and add only those participants you want to be eligible to the "White List".
Please note that we have an auto-approval kick in after 21 days, which means that participants' submissions will be automatically approved after 21 days.
You might also be interested in http://help.prolific.ac/creating-longitudinal-studies/delaying-payments-for-a-long-longitudinal-study.
Please note: If you want your participants to complete the follow-up studies at particular times, please make sure to specify this in your study description, including the times zone(s).
That's it! If you have any questions feel free to get in touch.