The item response theory irt, also known as the latent response theory. Comparison of classical test theory and item response. Demonstrating the difference between classical test theory. Demonstrating the difference between classical test theory and item. The item response theory irt provides statistical models which link the latent construct score of a patient to the questionnaire responses of the patient.
These models try to figure if theres an underlying trait that that accounts for your performance on a test. Classical test theory ct and item response theory irt 1950. These three books item response theory principles and applications, item. Item response theory irt vs classical test theory ctt. Lords book, applications of item response theory to practical testing. Download classical test theory versusitem response theory questions what is the ppt for free. For recent theoretical presentation of both methods. This study examined the psychometric properties of the model of human occupation screening tool, using both item response theory and classical test theory. His 1953 article is an excellent presentation of the basics of irt, and he also mentions. Reliability is seen as a characteristic of the test and of. 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.
This isnt a big problem on the classical test theory chapters, but more modern chapters such as the item response theory chapter need updating. Using classical test theory, item response theory, and. However, no manipulation of these axioms makes it a model of both item and test scores. Based upon items rather than test scores, the new approach was known as item response theory. It focuses on item response theory irt which requires stronger assumptions about the response. Classical test theory vs item response theory by chris. Comparison of item response theory and classical test.
Classical test theory ctt and item response theory irt are testing item assessment approaches. Demonstrating the difference between classical test theory and item response theory. Irt models are the current golden standard in this context, compared to the classical test theory ctt model where the latent scores are linked to responses by sumscores. An introductory 3day course introducing item response theory measurement models applied to psychological and educational data. 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. Classical test theory and item response theory slideshare. Introduction to classical test theory ji zeng and adam wyse psychometricians. 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.
When the classical test theory ctt is applied to relate the responses of the candidate to a score. Model linear non linear level test item assumption weak i. His 1953 article is an excellent presentation of the basics of irt, and he also. Multidimensional item response theory, or mirt, is an extension of irt and is used to explore the underlying dimensionality of an irt model. T or f item response theory has the advantage over classical test theory in that it provides more detailed information regarding each item on a test. Classical test theory ctt and itemresponse theory irt are testing item assessment approaches. This is the first of a series of powerpoints presented at a catirt workshop at the university of brasilia in 2012. 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. Neural test theory model for graded response data neural test theory model for graded response data shojima kojiro the national. The statistics produced under ctt include measures of item. Over the last 30 years item response theory irt has essentially replaced traditional classical test theory approaches to designing, evaluating, and scoring largescale tests of cognitive ability. Abstract item response theory irt is concerned with accurate test scoring and development of test items.
Over the past few decades, there has been a revolution in the approach to scale development. 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. Using familiar concepts from classical measurement methods and basic statistics, hambleton and colleagues introduce the basics of item response theory irt and explain the application of irt methods to problems in test construction, identification of potentially biased test items, test equating, and computerizedadaptive testing. Comparison of item response theory and classical test theory for powersample size calculation for questionnaire data with various degrees of variability in items discrimination parameters emilie schindler, lena e.
Irt is an example of what psychologists call a latent trait model. Comparisons between classical test theory and item. This chapter provides an introduction to irt, and discusses how it. There appeared a need to develop the methods of measuring behavior in. While the basic concepts of item response theory were, and are, straightforward, the underlying mathematics was. What it is and how you can use the irt procedure to apply it xinming an and yiufai yung, sas institute inc. Item analysis classical latent trait models rasch item response theory irt1 irt2 irt3 irt4 classical test theory classical analysis is the easiest and most widely used form of analysis. Classical test theory as a firstorder item response theory. However, a new test theory had been developing over the past forty years that was conceptually more powerful than classical test theory. The conceptual foundations, assumptions, and extensions of the basic premises of ctt have allowed for the development of some excellent psychometrically sound scales. This estimation allows for tailoring tests through judicious item selection to.
Ppt item response theory powerpoint presentation free. Irt may be regarded as roughly synonymous with latent trait theory. The classic source on gt is the book by cronbach et al. Lord 1951, 1952a, 1953 discussed test theory in a formal way that can be. Overview of classical test theory and item response theory. Comparison of classical test theory and item response theory.
One hundred and one people with mental health problems, aged 1865 years, were recruited. In psychometrics, item response theory irt is a paradigm for the design, analysis, and scoring of tests, questionnaires, and similar instruments measuring. Ctt and irt 5 scores, because we might apply ctt to one item tests and then it is a theory about item scores. You design test items to measure various kinds of abilities such as math ability, traits such as. The new psychometrics item response theory classical test theory is concerned with the reliability of a test and assumes that the items within the test are sampled at random from a domain of relevant items. Classical test theory spearman, 1904, novick, 1966focuses on the. Information is the analogue of reliability in classical test theory, but it has some important advantages. 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. Classical test theory an overview sciencedirect topics. Classical test theory ctt and item response theory irt. Item response theory columbia university mailman school. Clinical psychologists are advised to assess clinical and statistical significance when assessing change in individual patients. A comparative study of classical theory ct and item.
An introduction to using multidimensional item response. While the basic concepts of item response theory were, and are, straightforward, the underlying mathematics was somewhat advanced compared to that of classical test theory. Comparing classical test theory and item response theory. Fundamentals of item response theory sage publications inc.
The ctt and irt were compared across two samples and two forms of test on their. Item response theory statistical methods training course. Download as ppt, pdf, txt or read online from scribd. Called item response theory irt, this approach challenges the notion that scales must be long in order to be reliable, and that psychometric properties of a scale derived from one group of people cannot be applied to different groups. Displaying powerpoint presentation on classical test theory versusitem response theory questions what is the available to view or download. 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 of a number of problems associated with the classical theory of measurement, which cause inaccuracy in results i. Learn vocabulary, terms, and more with flashcards, games, and other study tools. It provides an introduction to item response theory irt, tying it to classical test theory and describing some of the major irt models. On the relationship between classical test theory and item response theory. Psychometric theory offers two approaches in analyzing test data. Item selection using ctt and irt with unrepresentative samples. Georg rasch 1960 published a book describing several item response models, one of which later became known as the.
Application to truescore prediction from a possibly nonparallel test. However, few studies have empirically examined the. Item response theory columbia university mailman school of. Item response theory irt is all about your performance on an exam, and how it relates to individual items or questions on a test. The statistics can be computed by generic statistical packages or at a push by hand and need no specialist software. Individual change assessment can be conducted using either the methodologies of classical test theory ctt or item response theory irt. Despite theoretical differences between item response theory irt and classical test theory ctt, there is a lack of empirical knowledge about how, and to what extent, the irt and cttbased item and person statistics behave differently. It is a theory of testing based on the relationship between individuals performances on a test item and. Item response theory and classical test theory university of hawaii. 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.
Classical test theory and item response theory provide useful methods for assessing content validity during the early development of a pro measure. An empirical comparison of thei item person statistics. Our fun worksheetquiz combo can help you identify how well you understand the classical test theory and the item response theory. Item response theory item response theory shortcomings of classical true score model sample dependence limitation to the. In psychometrics, the theory has been superseded by the more sophisticated models in item response theory irt and generalizability theory g theory.
Test dependent item response theory is essentially a nonlinear common factor model mcdonald, 1999, p. Despite its brevity, it has proved its value in classical test theory and item response theory assessments, the three traits have different correlates, and the measures appear to cover the range of subtraits e. Classical test theory is an influential theory of test scores in the social sciences. Chapter 8 the new psychometrics item response theory. The theory and practice of item response theory methodology in the social sciences. Classical test theory ctt and item response theory irt are widely perceived as representing two very different measurement frameworks. Classical test theory ctt, also known as the true score theory, refers to the analysis of test results based on test scores.
As a result, many of the issues that have arisen in the past 20 years are not treated in the book. First is the presentation of the psychometric properties of the mathematics. Kline 2005 suggests ctt is known for development of some excellent psychometrically sound scales, founded by charles spearman around 1904. Hinting at more recent theories and their goals such as item response 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. 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. Item response theory is a general statistical theory about examinee item and test performance and how performance relates to the abilities that. Classical test theory and item response theory the wiley.