Missing data/no response option for VAS scale

We are asking questions on a VAS scale. Is there a way to determine if a participant skipped a question? For example, our default value on the VAS scale is 0, when we export the data will we be able to determine if a person scored the item a 0 or if they didn’t answer the question? If not, is there a way to denote missing data using the VAS scale?

Hi, I have questions on a VAS as well–from memory, the respondent must interact with the VAS in some way for the answer to be recorded as an answer, otherwise it is recorded as an NA. So if the default is set to 0, and the respondent wants to record a 0 for the answer, they must hit + then -, or drag the VAS off 0 then back to 0 again.

But you can test this by releasing your draft survey to yourself and playing around with it!

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Exactly as @atdutoit explained, when you add a VAS question to your survey, similar to any other question, by default it does not have any answer. What you set as the default value in your VAS question is in fact the value which is shown to the participant. The question’s answer is still set to N/A by default.

So if the question is optional and the participant skips it, there will be no response to that question. If the participant wants to choose 0, they have to move the slider a bit (like moving it to 1 and then back to 0) in order to record 0 as the answer.

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Good point here and a trap to avoid. If you set a question as optional and a participant skips over it leaving the default response intact, you will never know whether they intended the default response, or they just didn’t answer the question.

As for all survey research, pilot early and often … :slight_smile:

To be clear, each question “Optional” has a property called “Confirm to Skip” which is set by default. So when the participant skips the optional question, the app moves the focus the question which is not answered and asks the participant if they are sure they want to skip answering that question. So if the question is not responded, that means the participant did not want to respond to it.