What does internal reliability measure?

Internal reliability measures the consistency of responses within different sections of the same test. This concept is crucial in psychological assessments and research because it ensures that a test provides stable and reliable results across its various components. For instance, a well-designed questionnaire should yield similar scores when measuring the same underlying construct across different items or sections. High internal reliability indicates that the items on a test are measuring the same concept and are correlated with one another, which strengthens the validity of the test.

Options that pertain to different aspects of reliability, such as consistency among different individuals taking the test, the ability to repeat the same results over time, or the agreement among various judges, address various forms of reliability like inter-rater reliability, test-retest reliability, or external reliability, but they do not relate to internal consistency specifically. Thus, the focus on internal coherence of test items is what confirms the correctness of the selected answer.