When choosing response options, make sure that they are:
- All possible alternatives are included in the response options, including: other (specify), don’t know, not applicable, non of the above as appropriate for the question.
- Mutually exclusive
- Each answer is unique and does not overlap. When writing the selection of responses for a structured question, you should make certain that the list covers all possible alternatives that the respondent might select AND that each of the answers is unique (i.e. they do not overlap). Adding "Don't know" to a response list for a question that some of the respondents may not be capable of answering will help ensure you are collecting valid data. However, you want to use the "Don't know" option sparingly. You should try to make sure that your respondents are capable of answering the majority of the questions on your survey questionnaire.
- Relevant to the question
- Irrelevant responses may distract the respondent and may add unnecessary length to your survey questionnaire.
- All of the responses should be similar so that no single response stands out to the individual except the answer that is true for them. Consistency simply helps to ensure that you are not leading respondents to a particular answer by making that answer different from the others. It also makes it much easier for respondents to find the answer that is relevant to them.