An open question is one where the range of possible answers is not suggested in the question and which respondents are expected to answer in their own words: ‘What did you eat for breakfast today?’ An open question may expect a short answer, where the anticipated answer would simply be one or more products, or it may expect respondents to talk as long as possible using their own words in order to give fully their answer, as in, ‘Why do you eat that brand of breakfast cereal more than any other?’ Open questions always seek a spontaneous, that is unprompted, response. In conversation, one person trying to start another person talking about a topic would use an open question.
The responses may be recorded verbatim as an open-ended question (‘Why do you eat…?’) or, with interviewer-administered surveys, a list of the most commonly given responses may be provided that can be coded (‘Which brand did you eat.?’).
Closed questions, on the other hand, tend, in conversation, to bring it to a stop. This is because there is a predictable and usually small set of answers to a closed question that the respondent can give. Any question that simply requires the answer ‘yes’ or ‘no’ is a closed question, and not helpful to opening out a conversation. An evening spent with a new acquaintance with both of you asking only closed questions would be very dull indeed.
In a research interview, closed questions also include any question where the respondent is asked to choose from a number of alternative answers. Thus any prompted question is a closed question.
Examples of closed questions are:
- ‘Have you drunk any beer in the last 24 hours?’
- ‘Are you aged under 25?’
- ‘Which of these brands of tinned meat do you buy most often?’
- ‘Which of the phrases on this card best indicates how likely you are to buy this product?’
The examples above are all closed questions, the first two because they can only be answered ‘yes’ or ‘no’, and the last two because there is a frame of possible responses from which the respondent is asked to choose.
Closed, and therefore pre-coded, questions are popular with researchers and interviewers alike because there is a set of answers known beforehand that can be listed on the questionnaire. With a paper questionnaire the interviewer only has to circle the appropriate code and that code can easily be entered into the data file by those responsible for data entry. With an electronic questionnaire, either the interviewer or the respondent only has to check the appropriate box and the data are automatically recorded and stored, ready for analysis. This type of question is usually easy to administer and cheap to process.
A questionnaire that measures behaviour is likely to consist mostly of closed questions (‘Which of these brands…?’, ‘When did you last…?’, ‘How many did you buy?’), whereas one exploring attitudes is likely to have a higher proportion of open questions. From the point of view of maintaining the involvement of the respondent, the interview should consist of a mixture of both types of question. (See Figure 4.1.)
Source: Brace Ian (2018), Questionnaire Design: How to Plan, Structure and Write Survey Material for Effective Market Research, Kogan Page; 4th edition.