Prolific is designed to help you recruit participants for your studies that are hosted elsewhere. All you need is a survey link to get started on Prolific!
Nearly all experimental software that is accessible via a shareable URL is compatible with Prolific. The main requirements are that the software:
- allows access via an anonymous link (i.e there is no sign-in required)
- enables you to record participant IDs in your study
- enables you to record participants as complete on Prolific
- does not record any personally identifiable information.
We have integration guides available for the most commonly used software. Let us know if you have a suggestion for other guides you'd like to see from us!
Recording participants' Prolific IDs
To link responses in your external survey / experimental software to participants in Prolific, you'll need to set up your study to record our participants' unique Prolific IDs.
This enables you to match our participant demographic data with responses. If you do not record participant IDs, you will not know who has submitted each individual study response. As a result, you won't know which ones deserve approval or rejection.
We recommend recording IDs automatically, which can be done using URL parameters. Alternatively, you can include a question in your study asking participants for their ID.
Option one: automatic recording of Prolific IDs via URL parameters (recommended)
If your experimental software supports it, you can get the participants' Prolific IDs from a query string. This means that participants won't have to copy & paste their IDs into your survey software, but instead the system will automatically enter the IDs for participants.
Firstly, you'll need to ensure that IDs are recorded in your data set.
Finally, parameters need to be added to your Study URL in order to pass the Prolific ID through the query string. To do this, tick the 'I'll use URL parameters' option in the Study Link section of the study creation form.
This will add the parameters to your study URL. The default name is 'PROLIFIC_PID' so you shouldn't need to change anything here, but parameter names can be changed by selecting 'configure parameters' if needed.
Your study URL should now look something like this:
When you publish your study, participants will each visit a unique URL of the form:
In addition, 'STUDY_ID' will be replaced with an ID unique to your study, and 'SESSION_ID' will be replaced with ID unique to the participant's submission. These parameters can be removed from your URL if you only wish to record participant Prolific IDs.
Option two: adding a question in your study
You can simply ask participants for their Prolific ID as a question within your study, like this:
Prolific IDs have 24 alphanumeric characters - please ensure the question field in your survey accepts both numbers and letters.
Recording participants as complete on Prolific
It is important to redirect participants back to the completion URL found on the study creation page, or provide them with a completion code.
This will look something like:
where 'I2PWSFRG' is the completion code.
Participants will visit this URL, or enter the code, to prove that they have completed your study. Therefore, this code should only be given to the participants who submit a complete and valid response to your survey.
Please make sure that participants' data has been submitted to your survey / experimental software before participants will have access to the completion URL / code.
There are two ways to provide a completion URL/code:
Option one: redirecting participants automatically via a URL (recommended)
Some survey / experimental software support redirecting to a URL at the end of each submission. In this case, simple insert the 'completion URL' provided by Prolific as the redirect URL, and participants will automatically be returned to Prolific upon successful completion.
Option two: providing a completion code for participants to copy and paste
If it's not possible to redirect participants automatically back to Prolific, you can also manually include the completion URL / code at the end of the study, and ask participants to copy and paste the code into Prolific.
Please preview your study to check that this is working smoothly before launching your study.
Please note that submissions marked with an incorrect completion code (such as NOCODE) are not necessarily invalid. Read more about the reasons why this might occur here.
Please see our integration guides for a step-by-step walkthrough of the above for the most commonly used survey / experimental software. You are also welcome to get in touch using the button below if you have any questions.