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Item-Score Reliability in Empirical-Data Sets and Its Relationship With Other Item Indices.

ABSTRACT: Reliability is usually estimated for a total score, but it can also be estimated for item scores. Item-score reliability can be useful to assess the repeatability of an individual item score in a group. Three methods to estimate item-score reliability are discussed, known as method MS, method ?6 , and method CA. The item-score reliability methods are compared with four well-known and widely accepted item indices, which are the item-rest correlation, the item-factor loading, the item scalability, and the item discrimination. Realistic values for item-score reliability in empirical-data sets are monitored to obtain an impression of the values to be expected in other empirical-data sets. The relation between the three item-score reliability methods and the four well-known item indices are investigated. Tentatively, a minimum value for the item-score reliability methods to be used in item analysis is recommended.

SUBMITTER: Zijlmans EAO

PROVIDER: S-EPMC6236637 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Item-Score Reliability in Empirical-Data Sets and Its Relationship With Other Item Indices.

Zijlmans Eva A O EAO Tijmstra Jesper J van der Ark L Andries LA Sijtsma Klaas K

Educational and psychological measurement 20170927 6

Reliability is usually estimated for a total score, but it can also be estimated for item scores. Item-score reliability can be useful to assess the repeatability of an individual item score in a group. Three methods to estimate item-score reliability are discussed, known as method MS, method λ6 , and method CA. The item-score reliability methods are compared with four well-known and widely accepted item indices, which are the item-rest correlation, the item-factor loading, the item scalability, ...[more]

PMID: 30542214

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