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There are various possible ways to set this up. Are the questionnaires going to be completed in paper or using an Airtable form? If each questionnaire will be an Airtable form, you will need to have one table per questionnaire. Otherwise, you might be able to have a single [Questionnaires] table.
In general I you want to have a new table for each type of person/place/thing that exists in real life. In this case I would expect to have the following tables (in addition to your table(s) for questionnaires.
- [Participants]
- [Staff]
- [Time Points]
You will also need linked record fields to show the relationships among the different entities. For example, you might have a junction table with linked records for the {Participant}, {Staff}, {Time Point}, and {Questionnaire} that go together.
I recommend looking at Airtable’s Guide to many-to-many relationships for more info.