The Interval Scale question type is a graphical representation of a Likert scale.
There is a pointer which the respondent moves to select the chosen Likert item. The Likert item is shown via a text bubble which automatically changes its text content depending on where the pointer is positioned on the line.
iOS And Android App
Both the iOS and Android apps support the Scale question type.
The Interval Scale question type should not be confused with the Scale question type which is similar to the VAS (Variable Analogue Scale) while the Likert scale has defined Likert items of divisions on the scale.
A typical Likert scale could be like this:
1. Strongly disagree
3. Neither agree nor disagree
5. Strongly agree
Whereas the Scale question type has a 0 – 100 graduation “behind the scenes” which the respondent is unaware of.
Likert scales are used for eliciting a respondent’s level of agreement or disagreement on a scale which usually has the same number of Agree and Disagree items on either side of a Neutral center point. Sometimes, depending on the purpose of your research, it is useful to not have a Neutral point but to force the respondent to have some level of agreement or disagreement with the given statement. While a 5 point scale is most often used some researchers also use 7 or 9 points. What you choose to use will depend on your requirements.
The scale is named after the well known psychologist Rensis Likert, an American who developed the scale as part of his PhD thesis in 1932 when he used it to identify the extent of a persons belief, attitudes and feelings towards international affairs. The scale has become widely used around the world since then.