Interval scale questions usually will include three to ten responses rated on a sliding scale. They are fairly common and can provide information in a client satisfaction questionnaire that is pretty easy to measure. Using this type of questionnaire, satisfied clients can quickly rank their perceptions in a few minutes. Some common rankings include:
♦ Not at all - Great extent
♦ Least like - Most like
♦ Poor quality - Excellent quality
♦ Worst choice - Best choice
♦ Poor - Outstanding
♦ Strongly disagree - Strongly agree
A few sample questions that could be used in an interval-scale are:
♦ To what extent did you like (product or service)? 1 being not at all; 5 being great extent: 1 2 3 4 5
♦ How would you rate our customer service department? 1 being poor; 5 being outstanding: 1 2 3 4 5
Avoid including more than one question in any of your questionnaire questions. For example, asking if the respondent likes both products and services in the same question only provides a vague answer, since you don’t know whether the answer is for products or services, or both.
Here’s a slight variation of the interval-scale. It’s taking one general question and then breaking it down into more specific areas with individual questions.
♦ What kind of impact has our (product or service) had on you 14 days later? 1 being not at all; 5 being great extent:
- a. It is something I am able to use weekly. 1 2 3 4 5
- b. Lived up to the promises made by the sales department. 1 2 3 4 5
- c. I will purchase the complimentary (products or services). 1 2 3 4 5