Overview of classical test theory and item response theory. The theory and practice of item response theory methodology. Educational and psychological measurem june 1998 v58 n3 p357. Item response theory also known as modern measurement theory, a latent variable modeling approach to item analysis and test construction. The construction, principled use, and systematic evaluation of such tests often require. Item response theory irt is used to evaluate the relationship between a latent trait, such as mathematical ability, quality of life, or patient satisfaction, and the test questions or items intended to measure that trait. Our fun worksheetquiz combo can help you identify how well you understand the classical test theory and the item response theory. May 31, 2015 classical test theory ctt and item response theory irt are testing item assessment approaches. A course in item response theory and modeling with stata is an outstanding text both for those who are new to irt and for those who are familiar with irt but are new to fitting these models in stata. Whereas classical test theory focuses on the test as a whole, item response theory shifts its focus to the individual items questions themselves. Comparisons between classical test theory and item response theory in automated assembly of parallel test forms the journal of technology, learning, and assessment volume 6, number 8 april 2008 a publication of the technology and assessment study collaborative caroline a. As a result, many of the issues that have arisen in the past 20 years are not treated in the book. Item response theory is based on more computerintensive techniques, involving fitting models to the data maximum likelihood estimation. Both theories enable to predict outcomes of psychological tests by identifying parameters of item difficulty and the ability of test takers.
If youre a key worker, you can apply for an emergency theory test. You design test items to measure various kinds of abilities such as math ability, traits such as. Comparisons between classical test theory and item response. B requires more of the items in the test to conform to the model.
Abstract item response theory irt is concerned with accurate test scoring and development of test items. The basics of item response theory using r frank b. Pdf a primer on classical test theory and item response. Using classical test theory, item response theory, and rasch. Model linear non linear level test item assumption weak i. Theory tests have been suspended because of coronavirus covid19.
Mismatch between individual ability and test difficulty can further. Both are concerned to improve the reliability and validity of psychological tests. There are various approaches in the construction of tests using item response theory. The measurement models better known and used currently are mentioned, the classical test theory ctt, and item response theory irt, including the rasch model. The following demonstrates a simulated dataset of 20 students true scores and their raw scores on a 10item test.
Over the past several decades, item response theory irt and item response modeling irm have become increasingly popular in the behavioral, educational, social, business, marketing, clinical, and health sciences. Classical test theory and item response theory provide useful methods for assessing content validity during the early development of a pro measure. Classical test theory ctt and itemresponse theory irt classical test theory ctt and itemresponse theory irt are testing item assessment approaches. Psychometric theory offers two approaches in analyzing test data.
But such relationships have rarely been empirically investigated, and, as a result, they are largely unknown. In this book, raykov and marcoulides begin with a nontraditional approach to irt and. Comparing classical test theory and item response theory. Classical test theory is an influential theory of test scores in the social sciences. In addition, the authors provide overviews of instrument construction and differential item functioning.
In psychometrics, the theory has been superseded by the more sophisticated models in item response theory irt and generalizability theory g theory. Classical test theory assumptions, equations, limitations, and item analyses c lassical test theory ctt has been the foundation for measurement theory for over 80 years. Item response theory irt is all about your performance on an exam, and how it. Using classical test theory in combination with item response. Jul 15, 2015 item response theory is a general statistical theory about examinee item and test performance and how performance relates to the abilities that are measured by the items in the test. Demonstrating the difference between classical test theory. Item analysis classical descriptive analysis of itemlevel data, with an emphasis on difficulty, discrimination, and contribution to internal consistency. This graduatelevel textbook is a tutorial for item response theory that covers both the basics of item response theory and the use of r for preparing graphical presentation in writings about the theory.
Comparative study of classical test theory and item response. It can be concluded that ctt and irt should be be viewed as rival theoretical frameworks. Irt is an example of what psychologists call a latent trait. In part, this may be due to advertising about the advantages of irt over ctt. However, few studies have empirically examined the. Basics of classical test theory california state university. Item response theory has become one of the most powerful tools used in test construction, yet. Trait true score observed score classical test theory. Life science high school precalculus textbook college calculus textbook. Kline 2005 suggests ctt is known for development of some excellent psychometrically sound. Item response theory requires several items so that there is adequate opportunity to have a sufficient range for levels of item difficulty and person attribute. Pdf test theory, classical test theory researchgate. Test construction using ctt and irt with unrepresentative samples item response theory irt has clearly gained mindshare among io psychologists and researchers, as well as psychometricians.
To provide comparisons and a worked example of item and scalelevel evaluations based on three psychometric methods used in patientreported outcome developmentclassical test theory ctt, item response theory irt, and rasch measurement theory rmtin an analysis of the national eye institute visual functioning questionnaire vfq25. This isnt a big problem on the classical test theory chapters, but more modern chapters such as the item response theory chapter need updating. Two introductory books are suggested to students and professors interested in irt for. Both classical test theory sum scores and item response theory estimates measure the same underlying dimension, but differences in the two scales may lead one to be more preferential than the other in interpreting data.
Item response theory irt vs classical test theory ctt. It is a theory of testing based on the relationship between individuals performances on a test item and the test takers levels of performance on an overall measure of the ability that item was designed. We propose here that item response theory analyses complements the basic ctt techniques presented in janssen and meier 20. Which of the following conclusions about item response theory distinguishes it from classical testing theory. Irt may be regarded as roughly synonymous with latent trait theory. Using classical test theory, item response theory, and. Item responses can be discrete or continuous and can be dichotomous and the item score categories can be ranked or non ranked. The theory and practice of item response theory methodology in the social sciences. Item selection using ctt and irt with unrepresentative samples. Item response theory irt and classical test theory ctt are invaluable tools for the construction of assessment instruments and the measurement of student proficiencies in educational settings.
D includes classical true score theory as a special case. Item response theory irt has become a popular methodological. Using 2008 your first college year yfcy survey data from the cooperative institutional research program at the higher education research institute at ucla, two scales are built and testedone measuring social. The conceptual foundations, assumptions, and extensions of the basic premises of ctt have allowed for the development of some excellent psychometrically sound scales. Classical test theory ctt and item response theory irt.
Founded 1947, ets pursues research in statistics and psychometrics, making major contributions to areas such as classical test and item response theory, equating test scores, factor analysis, largescale survey assessment research, and test fairness. A comparative study of classical theory ct and item. Item response theory irt is all about your performance on an exam, and how it relates to individual items or questions on a test. Classical test theory ctt, also known as the true score theory, refers to the analysis of test results based on test scores. Item response theory, classical test theory, item parameters. Introduction to educational and psychological measurement using r. Classical test theory ctt in psychometrics is all about reliability. Compared to ctt, irt serves as an alternative test theory that bears several desirable features. Item response theory is a newer theory with a focus on test items that adds more tools for solving measurement problems in psychology test bias adaptive testing item selection ctt focuses more on the total score of a scale or subscale. This course is intended to equip students to read the literature in their own substantive areas more critically, to use tests more intelligently in research. Item response theory columbia university mailman school of. Classical test theory vs item response theory by chris allred.
By using familiar concepts from classical measurement methods and basic statistics, this book introduces the basics of item response theory irt and explains the application of irt methods to problems in test construction, identification of potentially biased test items, test equating and computerizedadaptive testing. Item response theory provides powerful analytical tools that, even in their most basic applications, can be a valuable. Modern text books on test construction even do not present these approaches as opposed to each other but as complementing each other. An application of item response theory to psychological test. Item response theory is a stricter model for test construction than classical true score theory in that it. Lets say you re taking your history exam, and theres construction going on in the building. Item reponses theory ctt testoriented indices like reliability are groupspecific scores are testspecific contribution of item measured using other items e. A course in item response theory and modeling with stata. Nov 30, 2010 this study compares the psychometric utility of classical test theory ctt and item response theory irt for scale construction with data from higher education student surveys. Factor analysis as well as the major extensions and alternatives to classical test theory, generalizability theory and item response theory latent trait theory, are briefly introduced. Classical test theory ctt and itemresponse theory irt are testing item assessment approaches. To provide comparisons and a worked example of item and scalelevel evaluations based on three psychometric methods used in patientreported outcome development classical test theory ctt, item response theory irt, and rasch measurement theory rmtin an analysis of the national eye institute visual functioning questionnaire vfq25. In psychometrics, item response theory irt also known as latent trait theory, strong true score theory, or modern mental test theory is a paradigm for the design, analysis, and scoring of tests, questionnaires, and similar instruments measuring abilities, attitudes, or other variables. Basics of classical test theory theory and assumptions types of reliability example classical test theory classical test theory ctt often called the true score model called classic relative to item response theory irt which is a more modern approach ctt describes a set of psychometric procedures used to test items and scales.
Classical test theory ctt and item response theory irt are widely perceived as representing two very different measurement frameworks. It is sometimes referred to as the strong true score theory or modern mental test theory because irt is a more recent body of theory and makes stronger assumptions as compared to classical test theory. Item response theory is a statistical theory about items, test performance and abilities that are measured by items. What it is and how you can use the irt procedure to apply it xinming an and yiufai yung, sas institute inc. Item response theory irt, also known as latent trait theory or modern mental test theory. Another branch of psychometric theory is the item response theory irt. In this sense, classical test theory ctt has been extensively.
1206 529 554 526 106 947 775 1554 564 1469 405 581 1344 61 763 1283 1496 270 1190 50 1179 394 1050 262 1421 358 832 991 975 214 630 1301 1166 434 1101 238 24 435 1151 974 430