


These explanations will help you to understand reliability and validity information reported in test manuals and reviews and use that information to evaluate the suitability of a test for your use. This chapter provides a simplified explanation of these two complex ideas. You should examine these features when evaluating the suitability of the test for your use. These are the two most important features of a test. Test reliability and validity are two technical properties of a test that indicate the quality and usefulness of the test.

Internal Consistency Reliability: It is used to assess the consistency of measure across items within the test. In Parallel form, content is divided into two forms randomly but in case of split-half reliability we use odd and even numbers to divide the contents. Parallel form reliability: it is used to assess the consistency of measurement of two tests constructed in the same way from the same content domain of the same characteristics. We estimate test-retest reliability to administrate the same case to the same people on two different occasions. Test-retest Reliability: Test-retest reliability is used to assess the consistency of measure from one time to another. When the measure is a continuous one inter-rater reliability is used. Inter-Rater or inter-observer reliability: It is use to assess the degree of reliability of different raters or observers give consistent estimate of the same phenomena. Parallel-forms reliability/split half reliability.Inter-Rater or inter-observer reliability.There are generally four general classes of reliability: So, reliability is an umbrella term under which different types of score stability are assessed. Reliability is the measure of how stable, dependable, trust worthy and consistent a test is in measuring the same thing each time.Īccording to Anastasi, “ Reliability refers to the consistency of scores obtained by the same persons when they are reexamined with the same test on different occasions or with different sets of equivalent items or under other variable examining conditions”Īccording to Aiken, “Reliability is defined as the ratio between variance and observed variance” Reliability: reliability is the degree of consistency between the two measures of same thing (Worthen and others1993).
