I have data from another - extensive - survey in a database. Unfortunately, this database is incomplete, and we need to add more information to each item of the database.
Because the previous investigation was extensive and time consuming for the people that answered, we would like to create in LS a survey that shows the data already present in the previous database, asking to add only some information.
Sure you can. Use tokens with persistence and import previous responses using VW format.
As for importing the responses I suggest to set up the survey first as well as the token mechanism, create some dummy responses running the survey. Then export them to BW format and edit the export file adding your previous answers there. Then import back. You will need to create some dummy tokens which you will have to also import later as tokens. That will allow responses to be linked to tokens which can be used for editing responses.
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