How screeners work

Why it exists

A researcher is not looking for "anyone" but for specific people: for example, those who ordered food delivery in the last three months and live in Germany. The screener filters everyone else out before the study starts.

It is not an exam. There is no correct answer — there is a match or a mismatch with the conditions of that particular study.

Why inventing answers backfires

The temptation to shape answers to what seems expected is understandable, and it almost always loses. Most studies include control questions, and during the session the researcher asks follow-ups, so a mismatch surfaces within the first five minutes.

The consequences are unpleasant: the session is stopped, the reward is not paid, and your rating on the platform drops. Sometimes access to new studies is closed permanently.

Why you can be rejected even when you fit

Quotas fill quickly. A researcher may need eight people, and once the eighth agrees everyone else is declined, no matter how well they matched.

Another reason is sample balance. If a study already has too many participants of your age or profession, someone else is taken so the group is not uniform.

How to improve your odds

Fill in your profile completely and keep it current: most rejections happen because the system simply does not know a relevant fact about you.

• answer quickly — popular studies close within hours
• write two or three sentences in open questions, not one word
• update your data when your job, city or household changes
• do not apply to everything: a low acceptance rate hurts your rating