How Long Should A Market Research Questionnaire Be?

DSM Digital School of Marketing - questionnaire

A market research questionnaire should be as short as possible while – at the same time – ensuring that the researcher is able to gather valid and reliable answers to all questions that are asked of each respondent.

Questionnaire length, which is often referred to as length of interview or “LOI,” is usually measured by the average time that it takes a respondent to finish the whole questionnaire when it is administered in a comparable context to that in which it will eventually be fielded.

There is no objective limitation on how long a questionnaire may be, nor any definite maximum number of questions which it may contain. The mental burden that a questionnaire puts on a respondent will vary not only based on the individual respondent however also based on how the questionnaire itself has been created, what kinds of questions it contains as well as how and when it is administered, and many other factors.

The Psychology Behind Survey Questionnaires

In general, when there are a lot more survey questions participants tend answer quicker than they would with shorter surveys. Quicker responses mean less attention to detail, which jeopardises the accuracy of your findings. This means that it’s important not to ask more questions than is utterly required for responding to research questions.

A good rule of thumb that you should follow is to consider your target audience as well as when they’ll be taking the survey. Think about how much time that they’ll be willing to volunteer for this activity and also take note of the effort required for each question. The more difficult that the question is, the more time it’ll take to complete. For most organisations, the ideal number of questions you’ll want to include is less than 30.

What Should You Consider When Writing A Market Research Questionnaire?

While there are no hard-and-fast rules governing market research questionnaire length, there are a number of general guidelines that  good researchers tend to keep in mind when putting together questionnaires for ordinary market research contexts.

These regulations take into account the fact that because as questionnaire length increases, the ability of respondents to offer valid and reliable responses to each question decreases.

At the same time, response validity (i.e., data quality) ultimately deteriorates to the point that any further questions asked of the respondent are not worthwhile as the individual’s attention span and ability to provide valid answers has been utterly exhausted.

How To Select Questions For A Survey Questionnaire?

When it comes to the various types of questions you could potentially ask in your survey questionnaire, it’s really good to be aware of the full range of options which are available to you before you get down to designing your questionnaire. This is very important, as their simplicity or complexity can have a massive bearing on how long it takes a respondent to finish each one and thus how many questions your survey needs to have in total.

At the very highest-level, survey questions typically fall into one of two camps – open or closed questions:

  • Although open questions are qualitative in nature and have the aim of giving respondents as much space as they need in order to express their feelings when answering a question,
  • Closed questions are created to gather data much faster with respondents therefore typically being asked to give either Yes or No answers, or to choose their answers from a pre-set list of options.

Closed survey questionnaires are available in a broad range of formats. While multiple choice questions are usually presented to respondents with a single select or multi-select option, other formats – such as Likert scale, plus rating and ranking questions – can give researchers more information with respondents being asked to highlight how much they like, rate or rank something against the other options that is provided.

Get in touch with the Digital School of Marketing

Do you want to discover more about market research then you need to do our Market Research Course? Follow this link to learn more.

DSM Digital School of Marketing Digital Marketing course registration