Reliability and Measurement Error
Reliability and Measurement Error
Reliability is the degree to which measurements are free from error, making reliability inversely related to error. Reliability goes hand-in-hand with validity, as any reputable introductory research methods book will emphasize that reliability is a condition for validity. The amount of literature on the topic of reliability is further suggestive of its importance as the size of this literature dwarfs that of validity. Reliability and measurement error mirror each other. Understanding reliability requires understanding measurement error. In this chapter, the concept of measurement error is introduced from the perspective of classical test theory (CTT). The focus is on CTT because it serves as the foundation of reliability in social work research. An overview of the domain sampling model and the various types and sources of measurement error are then discussed, followed by different methods for assessing reliability. The chapter concludes with an overview of generalizability theory and item response theory, which are also used to conceptualize and evaluate measurement error.
Keywords: reliability, measurement error, classical test theory, validity, domain-sampling model, generalizability theory, item response theory
Oxford Scholarship Online requires a subscription or purchase to access the full text of books within the service. Public users can however freely search the site and view the abstracts and keywords for each book and chapter.
Please, subscribe or login to access full text content.
If you think you should have access to this title, please contact your librarian.
To troubleshoot, please check our FAQs , and if you can't find the answer there, please contact us .
