If you want to invite specific participants to take part in your study, there are two ways to do this:
Include approved participants from previous studies - useful for multi-part or longitudinal studies, or when you want to re-invite participants who completed an earlier study.
Use a custom allowlist - useful when you already have the Prolific IDs of the specific participants you want to invite.
Option 1: Include approved participants from previous studies
This option is particularly useful if:
You are running a multi-part or longitudinal study.
You want only participants who completed a previous study in a series to take part in the next study.
You experienced an issue with a previous study and want to give participants who were unable to complete it an opportunity to take part in a duplicate study after the issue has been resolved.
How to include approved participants from previous studies
When creating your study, scroll down to Recruit participants.
Select Add filters.
Search for include approved participants from other studies.
You can also find this screener in the Participation on Prolific category.
Select the studies whose approved participants you want to invite.
Only studies in your current workspace will be available to select.
Once applied, this screener will include only participants who were approved in the selected studies. Participants who were rejected, returned, or timed out will not be included.
Option 2: Use a custom allowlist
A custom allowlist lets you invite specific participants when you already have their Prolific IDs.
This can be useful when you want to invite a particular group of participants, and you can also add more participants to the allowlist after your study has been published.
How to create a custom allowlist
When creating your study, scroll down to Recruit participants.
Select Add filters.
Search for custom allowlist.
You can also find this screener in the Custom screener category.
Enter the Prolific IDs of the participants you want to invite.
Only participants on the allowlist will be eligible to take part in the study.
Once the study is published, participants on your allowlist will automatically receive an email invitation within one hour. You can also send them custom reminders using our messaging system.
How to get Prolific IDs
We recommend obtaining Prolific IDs from your Prolific data export or query string, rather than entering IDs manually.
Prolific IDs recorded manually in your survey may contain errors, and invalid IDs will be rejected from the custom allowlist.
See our guide on how to download your data export for more information.
Add participants to an allowlist after publishing
You can add more participants to your custom allowlist while your study is running. You will need to have an allowlist or participant group already created in order to view the below option:
Go to Projects > Open your study > Click on the study name to see your Submissions page.
Click the blue action menu on the top right.
Select Add participants to allowlist.
Enter the new Prolific IDs.
Click Append.
The new IDs will be added to your existing allowlist and will become eligible to take part in the study.
Important: You cannot remove participants from the allowlist of a published study.
Adding participants to your allowlist also does not increase the number of available places on your study. You can increase the number of places on most studies, except representative samples.
Important things to keep in mind
Specify when participants should complete the study
If you need participants to complete your study at a particular time, include this information in your study description, along with the relevant time zone(s).
If you want your study to be published at a specific time, you can also use the schedule publish feature.
Avoid adding additional screeners to a custom allowlist
When using a custom allowlist, be careful about adding additional prescreeners. Additional eligibility criteria can make participants on your allowlist ineligible for the study, meaning they may not be able to access it.
Participants on hold cannot take part
If a participant on your allowlist has been placed on hold, they will not be shown or be able to take part in studies.
If you need help with a participant who has been placed on hold, please reach out to our support team through the button at the bottom right of the page.