The most common mistakes when creating questionnaires

How to avoid the most common questionnaire mistakes

Every questionnaire is different: different goals, different participants, a different context. Even so, some rules apply to every questionnaire, and some mistakes come up again and again.

Mistakes in a questionnaire feed straight through into your data. A poorly framed question produces answers that look perfectly analysable but measure the wrong thing. Such mistakes are hard to spot afterwards and can no longer be corrected once the survey is out. That is why the quality of a survey is decided while the questionnaire is still being built.

This page is about the questionnaire itself: how to word questions, build answer options and scales, choose the right question type and lay out the questionnaire so it reads well. For running the finished survey, sending it out anonymously and in compliance with the law, and getting a good response rate, see Common mistakes in online surveys.

These are the most common mistakes when building a questionnaire, and how to avoid them:

Useful tips for avoiding the most common mistakes when creating a questionnaire

The most common questionnaire mistakes

Unclear questions

If a question leaves room for interpretation, respondents read it differently and the results are no longer comparable.

Imprecise questions

What seems clear to you has to be instantly understandable to someone without any background knowledge.

Leading questions

The wording influences how people answer and distorts your results.

Missing answer options

If the right option is missing, respondents pick something else or skip the question.

Imprecise answer options

Vague or overlapping categories cannot be analysed cleanly later on.

Too many questions

Asking everything at once risks confusion and high drop-out rates.

Texts that are too long

On screen people skim rather than read, so long question texts go unread.

Non-web-friendly typography

Font size, line width and typeface all help decide how readable your questionnaire is.

Matrix questions

Large matrix questions tire respondents and invite response patterns instead of genuine judgement.

Boring questionnaire

Monotonous questions make attention drift and drive the drop-out rate up.

What is LamaPoll?

LamaPoll is a survey tool for creating online questionnaires. Our survey tool lets you create, run and analyse online questionnaires quickly and easily. Create your questionnaire in just a few steps, customise it for your organisation and conveniently invite customers or employees by email. An online questionnaire enables you to gather insights quickly and easily to improve customer or employee satisfaction. You can register for the LamaPoll survey tool free of charge and immediately create and run online surveys with up to 50 participants. If you need more responses for your online questionnaire, simply choose one of our plans: billed monthly, cancel any month. You can also choose from our online questionnaire templates and examples.

Last updated on October 2, 2026


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