Issues with data - missing or lost

URL of experiment:

Description of the problem: I recruited participants with Prolific and can see there that a certain number of people did perform my experiment however the amount of data available in the “data folder” in the Gitlab account doesn’t match - about 8 participants (who received the confirmation code that they finished the experiment) are missing in the final data folder. Would it be possible that the synchronization with Pavlovia somehow failed?
It is not the first time I experienced it - about 40% of my piloting runs were not saved too for no apparent reasons. Therefore I was wondering if it was “normal” or what could go wrong.

Thanks in advance

When / how do they get the confirmation code?

Once participants reach the last slide of the experiment, they are redirected to another website (recruiting website - Prolific). There, I do have access to many things and can see who finished the experiment.
My problem is that I do have more participants who finished the experiment than “data/csv files” in my Pavlovia Gitlab data folder.

By redirected, do you mean via the completed URL in the online options?

Yes, at the far end, in the “jspsy.init.on_finish”, participants are redirected to Prolific via a completed URL. Their ID is in the URL so I know who did finish the exp.

Ah, are you using jspsych, not PsychoPy?

Yes, I do use JsPsych, sorry for the confusion. As it is for now, the “JS translation” of PsychoPy’s code is not sufficient for my tasks so I code my experiments in JsPsych.
As for the code itself, I copy pasted (with adaptations) the snippet provided by the Pavlovia website. It works, but not all the time for no apparent reason.

I’m in exactly the same situation as you @Aodaria. I also switched from PsychoPy to jsPsych. I host my experiment on Pavlovia and recruit participants from Prolific. I’m currently only testing small batches of participants on Prolific. I can see that 5 people have completed my task and was redirected back to Prolific via a completion URL. But 3 out of 5 participants’ data were absent from my Pavlovia Gitlab repository, another participant’s data file was present but it only contained data from the first 23 trials of the task (there are 104 trials in total in the experiment).

It’s really frustrating to not get data and still having to pay for it. I’d really appreciate it if someone could figure out what’s going wrong…

I’ve got a problem like this too… I’m paying for it, the participants are using pavlovia, but some data are lost…

I have the same problem for many times now. I am also using jsPsych for coding, Pavlovia for hosting, and Prolific for data collection. really hope this issue can be solved!

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I have the same problem and have lost data from 80 participants on Prolific! Very costly! Has anyone found a solution?

I’m sorry to hear that. Did you use the Prolific redirect via URL (as your completed URL) or the completion code to copy and paste method? If the latter, when did you show your participants the completion code?

We used the completion code, we showed it as the last part of the experiment.

Your participants may well have then closed the experiment and claimed their payment without actually finishing the study. This method should only be used if the completion code is given AFTER the end of the study (i.e. after completion).