Custom Recruitment Link
If you supply your own testers and wish to create a custom link, you can do so by using the Custom Recruitment Link. You can find this by clicking “Open tests” and, in your chosen project, click “Collect Responses.” There, you will find a number of different recruitment link options, and you can edit with the “Custom Recruitment Link.”
The Custom Recruitment Link allows you to set a variable to identify specific respondents without them having to specify their name or email. This can be done by placing an '?' at the end of the recruitment link that will be generated when you launch your test, followed by a 'variable=', where "variable" can be any word or phrase.
For example, we can use a variable called UID (Unique Identifier). If you append the recruitment link generated when you launch the test with ?UID=tester1, the result from the person who clicks on that link will be identified as tester1.