Link Protection with One time links

When sending a pool email distribution, you can protect the links from being shared with anyone else other than the intended recipient.

If you toggle on either Link Protection or One Time Links, the screener can only be used once per recipient on the confirm page of your distribution. Typically this is used to limit any sharing of the screener links or posting around forums. This restricts the audience for your study to exactly the recipients you emailed.

If you don't mind if your recipients share their screener links, then set the screener link setting to never expire.

If you want to restrict each recipient to be able to fill out their screener only once, and not be able to share the link, set this option to one time links that expire and choose how long you want the links to stay active before they expire. The default is 60 days, and this means your recipients will have 60 days from when you send the Pool email from Ethnio to fill out their screener.

These one time links work with a unique token and algorithm that can predict with 99.9% accuracy (depending slightly on the size of your distribution) if they have been filled out by the right recipient. They do not use cookies at all so are basically impossible to game or cheat.

The links look like this so nobody could ever possibly use it to get to a static screener link: