Hi there,

I will be running my online experiment soon on Prolific. I am trying to find a way to prevent multiple submissions by one participant in a session. Since I will be using Heroku, as per Prolific's guidelines, I need to select an option in Heroku that prevents multiple submissions per participant in each session. However, I am unable to find such an option on Heroku to select. Does anyone have any advice on this?

If I'm correct, a participant on Prolific cannot participate multiple times in a study. Furthermore, if you have numerous studies and want to exclude participants from a study, you can do that on Prolific:

Add Screener -> Participation on Prolific -> Exclude participants from previous studies

You don't need to select an option on Heroku, Heroku has nothing to do with participant selection.

Thank you so much Daniel.