A well designed questionnaire has a good appearance, is short and simple and covers topics relevant to the study question. It has a logical structure and a nice layout. Well designed questionnaires can attain a high response rate and allow for an easy data summarisation and analysis. The Seven Golden Rules are helpful to design appropriate questions.
Questionnaire should always be accompanied by a cover letter (if administrated by mail) or an introduction by the interviewer. The introduction should include information on:
Confidentiality should be guaranteed. The time requested to fill in the questionnaire or the length of interview should be indicated correctly. Most importantly, the introduction should clarify the usefulness of the study to the potential respondents and convince them to participate.
The first page of a questionnaire should include the return address and the study title in bold. All pages should bear an identifying mark or a unique identifier, page numbers and directions for interviewers or interviewees. The items should be numbered. If you are choosing to send a questionnaire by mail, the sending should always include a self-addressed and prepaid envelope to facilitate a response.
Be aware that the order of the questions asked might influence the answers. It is recommended to group the questions by topic. The starting questions should be simple, relevant to main subject and non-threatening in order to put the participants at ease and catch their interest. Although frequently done, neither demographic nor personal questions are a good start for the interview or a written questionnaire. The first questions should serve to get the participants "in the mood" for the topic of interest.
The biggest challenge in designing a questionnaire lies in keeping the focus on the research question. Sidetracking should be avoided at all costs. Avoid collecting unnecessary information that does not help answering your research question. However, demographic information should be collected.
Conclude the questionnaire by thanking the respondents for their participation and ensuring them that their participation was really helpful. At this stage participants should have the opportunity to ask questions on the study or the subject they were interviewed on. If needed, ask for permission to make further enquiries and record the telephone numbers of those who consented to do so.