Hello all,
we would like to generate a survey for a medical study with lime survey. The people wanting to participate in the study will first register on an external webpage. We would like to design our survey so that:
1) participants first register on the external site
2) after registration on the external site they receive a unique identifying number generated by this external site
3) they then click on a link and thus are brought to the survey on Limesurvey
4) here they then enter the unique identifier (copy pate) that was given to them by the external site.

Is this possible and if so could someone kindly point me to how this might be done. 
Thank you so much in advance!

Please do not cross-post.

You asked this in the German part and I gave you a long answer.

Joffm

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