It is against the policy of Prolific to allow the use of screeners in studies.
At the same time, researchers often want to screen participants from within studies.
Researchers are particularly keen to use in-study screeners when
- There is no Prolific screener that quite matches their requirement
- There is a need for participants to have something which varies, e.g. a stand alone mouse (as opposed to touch pad or ball) which can’t be included in Prolific screeners since it may vary - the equivalent of state rather than a trait in psychology.
At the same time again, it is unfair to participants to break up their day, have them read consent forms, input their Prolific ID, and then be screened out despite expecting the full reward. This sort of unfairness may lead to dishonesty, and poor data.
Hence, how about creating a new type of “Screened Study” which is announced in a different way “New Screened Study on Prolific,” displayed in a different colour (perhaps with title on a red background), with a graphic (perhaps a warning triangle) with a set bonus/reward paid to those who are screened out.
That way those participants who do not want to be screened out can ignore such studies. Those who are screened out are paid fairly. And researchers can include a screener in case when such a screener does not exist, or cannot exist because it is a state not a trait.