We have a project that involves a known list of potential project participants, with email addresses, and so a token-based survey is a good solution. The token table will have one additional attribute (attribute_1) - an external study ID - which will be pre-populated for the known set of participants. The external study IDs are of the form CS-0000001, CS-0000002, CS-0000003, and so on.
We would also like to have the option for public registration, so that additional people can participate. Limesurvey's "allow public registration" option will insert a token into the token table for these new registrants, but we would also like to insert a new external study ID into attribute_1 when the new token is created. The external study ID must be unique, and can simply be an increment of the last attribute value in the token table. The new registrant should not need to input the study ID him/herself at the time of registration.
Does anyone know if this is possible in Limesurvey? This capability will greatly simplify our project and remove the need for two different streams of data handling (those known up-front, and those participating via a wider registration approach).
