You wrote to my question regarding anonymous questionnaires:
I don't know if the researchers are willing to change their methodology just for you, but it's easy to meet all the requirements you listed: Put your questionnaire answers in a blank envelope and seal it. Enclose the blank envelope in another envelope. The outer envelope has your name and various other information, i.e., everything needed to create the audit trail. When it arrives, the researchers (whom you must trust) open the outer envelope, remove the blank inner envelope, and toss it irretrievably into a pile with all the other blank inner envelopes. There would be no record of which questionnaire went with which respondent, but there would be a clear record of who's responded and who hasn't.
This system would not provide
1. Correlate my answers to the answers of my partner.
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