If you want people to be able to return to modify their answers later, to be able to complete the questionnaire in several sessions, or to be able to prevent the same respondents from responding several times, you can:
2.) Switch on the Maintain respondent session setting
Both these settings can be found in the questionnaire settings under the General tab.
Please note that if you have the Maintain respondent session setting on and the respondents are using the same device to answer the questionnaire, they should be advised to use their internet browser's incognito or private browser window. Otherwise the system will overwrite the answers every time a new respondent replies. It is therefore advisable to not switch the setting on in such a situation.
How does this actually work? How are you tracking respondents' answers?
Using these mechanisms, we keep track of a respondent via the respondent identifier. The exceptions to this are:
- the user clears the browser cache (this will also clear out local storage)
- the 'Maintain respondent session' setting of the questionnaire is not set
- the respondent is NOT signed in and:
- more than 7 days have passed since the respondent was last active
- more than 30 days have passed since the respondent was first active
- more than 60 minutes have passed since the respondent clicked "Done!" and submitted their responses
The most common case where new identifiers are issued is when the 'Maintain respondent session' setting is switched off. This is often used to protect respondents in situations where the questionnaire is filled out on shared / communal devices.
Similarly, the 60-minute cutoff after submission is intended to protect a respondent that has filled out a questionnaire on e.g. a library computer and forgotten to clear the browser cache.
Furthermore, please note that if a respondent is SIGNED IN, none of the time limits apply. It may still be possible for a signed-in respondent to receive several respondent identifiers. This could be the case if for example the 'Maintain respondent session' setting is off, or if the respondent logs in halfway through the response process (however, this would require fairly creative navigation on the part of the respondent). However, in these cases the respondent will still have access to both sets of responses via their account management pages.
So taking all the above into account:
1) If you want for users to be able to return to their previous responses in all situations, MAKE THEM SIGN IN. In some cases, this capability is actually important for legal / compliance reasons, which is why signing in can be enforced in the questionnaire settings.
2) In all other "normal" browsing situations the 'Maintain respondent session' setting should suffice to allow people to comfortably finish their questionnaires, even if their browser accidentally crashes, they go out to dinner, or they only come back to the questionnaire after a weekend at the summer cottage.