Classical Test Theory

Measurement is the process of quantifying the characteristics of a person or an object. Theories of measurement help to explain measurement results (i.e., scores), thereby providing a rationale for how they are interpreted and treated mathematically and statistically. Classical test theory (CTT) is a measurement theory used primarily in psychology, education, and related fields. It was introduced at the beginning of the 20th century and has evolved since then. The majority of tests in psychology and education have been developed based on CTT. This theory is also referred to as true score theory, classical reliability theory, or classical measurement theory.

Classical test theory is based on a set of assumptions regarding the properties of test scores. Although different models of CTT are based on slightly different ...