Millisecond Forums

Duplicate subject id

https://forums.millisecond.com/Topic31058.aspx

By abhi - 3/11/2021

Hi,

In two of my recent studies, I found two subjects having the same subject id/confirmation code. Most likely its the same subject repeating the study, as the other demographic info is the same.

I was wondering that if someone clicks the link twice, won't they be given a unique id/confirmation code each time? Is there a way to avoid duplicate ids? (I used sequential confirmation code generation); If I use random generation will it solve ?).

Thanks.
By Dave - 3/11/2021

 
abhi - 3/11/2021
Hi,

In two of my recent studies, I found two subjects having the same subject id/confirmation code. Most likely its the same subject repeating the study, as the other demographic info is the same.

I was wondering that if someone clicks the link twice, won't they be given a unique id/confirmation code each time? Is there a way to avoid duplicate ids? (I used sequential confirmation code generation); If I use random generation will it solve ?).

Thanks.

It's likely the same person, and typically them having the same ID if they launch multiple times in a row is desirable (otherwise you could not readily see that it's the same person). I don't think there is a way to avoid this; if you have Inquisit generate the IDs -- whether random or sequential -- the ID is generated when a participant hits the experiment's start page. If the page is not refreshed, the ID will remain the same.