Certification Board of Infection Control and Epidemiology (CBIC) Practice Exam 2025 – The All-in-One Guide for Exam Success

An interval scale of measurement provides numerical distances between intervals, which is a defining characteristic of this type of scale. In interval measurement, not only are the values ordered, but the exact differences between the values are meaningful. This allows for a range of statistical operations, such as addition and subtraction, to be performed with the data, making it possible to analyze differences and relationships effectively.

For instance, temperature measured in degrees Celsius or Fahrenheit is an example of an interval scale because the difference between 10 degrees and 20 degrees is the same interval as between 20 degrees and 30 degrees. Consequently, researchers can quantify the exact differences in temperature, unlike other measurement scales that do not allow for such direct comparisons of magnitude.

While the other options touch on different types of data measurement, they do not accurately describe what an interval scale specifically offers. Qualitative data lacks numerical value, ordinal values rank items without indicating the precise difference between them, and a measure of central tendency refers to methods of summarizing data rather than a type of measurement scale. Thus, the accurate representation of an interval scale is its provision of meaningful numerical distances between intervals.