At the time of creating a project, you can upload an NDA - which can contain any details you wish about the study.
At the point at which participants opt-in to participate in the study via the screener, they are required to read and agree to the terms and conditions held in the NDA you've uploaded before they are allowed to submit their responses. If a participant doesn't agree to the terms (i.e. they select "No") they will appear as "Not Qualified" for your project.
When research participants get to the end of the survey if an NDA is present this is what they see:
NDAs can be added as files or links on the screener section of your project.
Complete the project set up through to the Screener Questions.
Add the Screener questions you want
At the bottom of the Screener, there is and NDA field option -- Select either "File" or "Link"
Upload the file or add the link to add the NDA to your project.
The platform does not facilitate the return of the signed NDA to the researcher. If you require a signed NDA, you can distribute this directly with Respondents via the 'Messages' tab of your project to request a signed copy.