Test–Retest Reliability

Reliability estimates utilizing a test–retest approach measure the degree to which the same testing instrument produces similar results when administered to the same individual in as similar a manner as possible over a period of time. Test–retest reliability is a popular form of reliability estimation for the development and validation of test instruments and is based on correlation. Test–retest reliability falls behind only internal consistency estimates (e.g., coefficient α) in popularity for the evaluation of reliability. Test–retest reliability is a measure of test consistency and score fluctuation emphasizing the psychometric assessment of test form stability over a period of time. For instance, if an intelligence test is administered twice to the same individual within a short period of time, then a high test–retest reliability coefficient ...