Not showing link when reserving place


I’m here to discuss a thing that has recently come to my attention when analyzing the data from my latest study. I found duplicates in the Prolific ID, especially I’m speaking of some cases where the same participant returned a submission the first time because of failing attention checks, and then managed to enter the study again, not failing the attention check this time, and submitting a new response (thus being his/her status awaiting review).

I believe this is possible because of the fact that when participants “reserve” their place to enter a study, they are shown with the actual study link that can be copied & pasted. I’m referring to the pop-up window is such in the example below:

What do you other guys think about it? Are you concerned about this problem?

Let’s think about it…


Hey @Veronica, thanks for bringing this to our attention! I’ve passed it along to the Data Quality Team. I’ll let you know what they think! :slight_smile:

Just to clarify, was the duplicate submission displayed on the Prolific dashboard i.e. did the participant have two separate submissions, one that said ‘returned’, and another that said ‘awaiting review’?

Hi @Josh,

Thanks for passing the question to the Data Quality Team!

To be more precise, apparently, in the Prolific export there is only the ‘Awaiting review’ submission. But when I look into my survey data export I have records of both submissions for the same participant. So both the ‘failed’ one & the submitted one, having the first one occurred before the second.

Let me know if you need more info!

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I’ve spoken to the team. There’s not much we can do once the participant leaves the site and has access to the URL for your study. They are able to ‘re-enter’ your study by using the link displayed to them in the browser. But, you won’t pay twice for a submission because our system does not allow a participant to have multiple submissions at once. So, if they return their first submission, they won’t be paid for their 2nd, as the system won’t allow it.

We advise that you use your external study software to block multiple entries by the same participant ID, or implement IP blocks to stop multiple entries.

I’m sorry that we can’t help further!

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