Prolific uses multiple layers of verification to ensure each Prolific ID belongs to one unique, real person — so your exclusion lists and participant data are reliable.
IP address detection to prevent the same device participating more than once
Email address and phone number verification at account creation
Identity checks using industry-standard technology (Onfido, an Entrust company) — participants complete a face scan to confirm the account owner is the person completing submissions
Account freezing if a participant doesn't complete verification on time — they must redo all onboarding steps before regaining access
We also run continuous integrity monitoring — analysing submission patterns, login activity, and device signals to detect suspicious behaviour. When triggered, participants must complete a verification check before they can continue on the platform. Duplicate accounts are banned, and anyone whose previous account was closed or deleted cannot create a new one.
What this means for your research
These safeguards work together to ensure each submission comes from a unique, verified individual and that your dataset remains clean and trustworthy. If you have concerns about specific participants in your study, you can report them via the data quality form and our team will investigate.
For more information on how we monitor our participant pool for bots and other suspicious activities, see this blog. See also: How does Prolific prevent participants from sharing or selling their accounts?