Which type of reliability is demonstrated when two different forms of the same test yield similar results?

• A. Test-retest reliability
• B. Inter-rater reliability
• C. Parallel-forms reliability
• D. Internal consistency

Answer: (C)

When two different forms of the same test yield similar results, it shows parallel-forms reliability. This type evaluates whether alternate versions, designed to cover the same content and have similar difficulty, produce comparable scores for the same person. The idea is that if the forms are truly equivalent, a student’s score should be similar across them, reducing effects like memory from prior exposure or practice. This differs from test-retest reliability, which looks at stability of scores over time using the same form; inter-rater reliability, which concerns consistency between different scorers; and internal consistency, which examines how well the items on a single form measure the same overall construct. So, using two equivalent forms and obtaining similar results demonstrates parallel-forms reliability.