Open-Ended Questions

Last week I wrote about a questionnaire with all open-ended questions.  A questionnaire with all closed-ended questions would be just as bad.
Open-ended questions are important to find out what respondents are really thinking, in their own words. They provide important qualitative insights.  Here are some suggestions for using essay questions at the beginning, middle and end of questionnaires.

Beginning of Questionnaires - When writing product and service satisfaction research, I like to start the questionnaire with two open-ended questions:

1. What, if anything, do you like about Acme-brand Earthquake Pills?
2. What, if anything, do you dislike about Acme Earthquake Pills?

This enables us to capture, in the respondents' own words, their likes and dislikes, before we then bias their perspective by asking them to rate a bunch of attributes that we selected.  If you've designed your list of attributes appropriately, the verbatim responses will give you some color commentary about those items.  If you've designed your list poorly, and it doesn't reflect customers' real concerns, the verbatim responses will reveal that as well.

Middle of Questionnaires - For web surveys, respondents often find essay questions taxing, since they take more time and thought to complete.  Accordingly, I try to minimize my use of such questions in the middle of the survey, using them in cases where I can't anticipate common choices in advance or where it is important to hear respondents' comments in their own words. 

End of Questionnaires - For almost any long questionnaire I write, I like to conclude with two open-ended questions:

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What are some of your best practices for open-ended questions?