Given the importance of labeling each point in a scale, how do you decide the right labels to use in those circumstances when no common rating scale is appropriate?

 

If you are simply developing a list of choices to a choose-one question, and those choices have no relative relationship to one another, than you are not developing a rating scale.  When you report on these choices, you will simply report on the frequency with which each choice was selected and highlight the most frequently selected choices. Use these choose-one best practices to come up with the appropriate choice list.

 

For a rating scale, on the other hand, you want each label to represent a standard interval from one another. You plan on reporting on the arithmetic mean of the answers, not just choice frequencies, and you may try to discover correlations between the numeric rating and other variables in the survey.  How to label the scale depends in part on whether the scale is unipolar (ranging from 0% to 100% of a property) or bipolar (where the zero point is in the middle and the end points are opposites, such as “completely dissatisfied” and “completely satisfied”).

 

If you are developing a unipolar rating scale, use a five-point numeric scale such as 0 to 4 or 1 to 5, choosing a label for each point.  A common approach to unipolar scales follows this wording:

For a bipolar rating scale, use a seven-point scale ranging from -3 to 3, choosing a label for each point.  Bipolar rating scales are easier to write, as the wording should be in parallel for positive and negative items with the same absolute value. For instance, for measuring satisfaction, a good bipolar scale is:

• Completely dissatisfied
• Mostly dissatisfied
• Somewhat dissatisfied
• Neither satisfied nor dissatisfied
• Somewhat satisfied
• Mostly satisfied
• Completely satisfied

Purists typically insist that the midpoint take the form “Neither satisfied nor dissatisfied” but others prefer to label the midpoint “Neutral” for succinctness.

 

If you want to use a different word or phrase for each label, take care that the words are approximately equally apart.  For instance, Jon Krosnick and Leandre Fabrigar in “Designing rating scales for effective measurement in surveys” summarize the results of four studies into scale values for labels assessing liking.

 

 

Clearly, the scale “Very Poor, Poor, Fair, Good, Excellent” does a good (but not excellent!) job of spacing out each label.  To develop an original scale such as this requires pre-testing and is probably inappropriate for most business researchers to attempt.  In those cases where no other rating scale will do, instead use a five-point unipolar scale with just the endpoints labeled or a seven-point bipolar scale with the endpoints and midpoint labeled. While not ideal, and against best practices, you are less likely to go wrong using such an approach than simply making up a scale of your own.