Open-ended questions are those in which respondents type a response in a text box rather than selecting from a predefined set of responses (radio buttons, checkboxes, drop-down lists, etc). When open-ended questions are used properly, they can provide a number of benefits. However, when used improperly, they can be the kiss of death for your survey.
As noted in a previous entry, one common mistake is to use too many open-ended questions in a survey, which may cause many respondents to abandon the interview. Another common mistake made by inexperienced researchers is to force responses to an open-ended question even when it is likely that many or most respondents will have no valuable response to offer.
An example of this would be the question:
Do you have any other comments or suggestions about our company?
If the survey software is programmed to require a response to this question, it is likely that many respondents will be frustrated when they receive an error message telling them they have to type a response before they can proceed to the next question. When this mistake is made, the open-ended responses often include a rash of expletives.
The bottom line: As a rule, a response to an open-ended question should only be required when it is reasonable to think that every respondent will have a meaningful response to offer. Otherwise, a response should be optional.
