I want to do a survey with three measurement points:
Measurement point 1(t1): before a 30-minute walk in the field
Measurement point 2(t2): after a 30-minute walk.
Measurement point 3(3): Ten days later.
At t1 and t2 I will be where the walk starts and ends and give them the tablets to answer the questionnaires. T3 will take place 10 days later and participants will answer the questionnaire at their homes.
I want to look at changes over time, so I need to be able to assign the data of t1 of one person to the corresponding t2 and t3 data to see, if there are changes over time. I could do that by including a question with a personal identification code, but my experience has shown that people forget the code or there are a lot of mistakes which make it impossible to assign the datasets of the different measurement points of one person to each other. Thus, I would like to have personalised, but still pseudonymous accesess for each participant in my survey somehow. First I thought of collecting the email adress of the participants in questionnaire 1 and sending them a personalised link on their email adress, which is somehow marked, so I can assign it to a identification code instead of the participant. But the thing is that I want to realise a offline survey, so participants will not have internet access during the experiments on the tablets I give them, to answer the questionnaire. Which other possibilities are there for surveys with various measurement points to assign the data of the measurement points to each other?
Further, I need to collect the email address of the participants, because I want to send them a file containing a task they should fulfill when they are at home. Is there a possibility to send a simple word document via sawtooth to a mail adress? And since the email address is personal data, the email address should be saved separately from the rest of the responses to the questionnaire, so it is still anonymous. Is there a possibility to do this? And do I need to sign some data security agreement for that?
Thank you for the help,