Page 91 - Development of Questionnaires for Quantitative Medical Research

● Interval data

In interval scales, the numbers are aligned with

each other on a continuum and the division

between each number has an equal difference. This

is unlike in ordinal data, where the gaps between

the numbers are usually not identical. For

example, when measuring temperature, the 10-

degree Celsius difference between 20 and 30 is the

same as the 10-degree Celsius difference between

80 and 90. The zero in interval scales represents a

value, rather than a true zero. Examples of interval

scales are the Celsius and Fahrenheit temperature

scales, in which a zero degree does not indicate an