REDCap:How to - Ensure anonymity and have prizes
You want to give a prize as an incentive for your survey?
Great, then take a moment to analyze your data privacy requirements.
Case 1: Pseudo-anonymization is sufficent
In case that pseudo-anonymization is sufficient for your survey, you can create two instruments in one REDCap project, one containing the survey, followed by an instrument to collect the contact data for the prizes. Be aware that the answers of both instruments will belong to the same record_id.
If you first collect informed consent as described in REDCap:How_to_-_Survey_with_informed_consent, you probably don't want to invite people to the prices if they are not participating in the survey. In that case, you CANNOT link to instruments together, because the stop action will take you to the next survey, and not to the end.
You can always use the approach of case 2.
Case 2: You need full anonymization
In that case, you need to create two REDCap projects. One project will contain your survey, and the other project will contain the prizes. Modify the end of survey text of the first project to display the link to start the second survey.
In case of asking for consent, use the stop-field method of REDCap:How_to_-_Survey_with_informed_consent to provide the link only to the persons that agreed to survey participation.
Be aware that depending on the number of participants, it can be possible to connect the answers of both surveys based on record_id or timestamps. The access to the data of prizes should be very limited.