The test blueprint is important in test development, where it guides the test item writer in creating test items according to the desired objectives and specifications or characteristics (so-called a priori item characteristics), such as the level of item difficulty in the category and the distribution of items based on their difficulty level.…

As the largest international study ever taken in history, the Trend in Mathematics and Science Study (TIMSS) has been held as a benchmark to measure U.S. student performance in the global context. In-depth analyses of the TIMSS project are conducted in this study to examine key issues of the comparative investigation: (1) item flaws in mathematics…

When comparing data derived from tests or questionnaires in cross-national studies, researchers commonly assume measurement invariance in their underlying scaling models. However, different cultural contexts, languages, and curricula can have powerful effects on how students respond in different countries. This article illustrates how the…

Item bias has been a major concern for test developers during recent years. The Mantel-Haenszel statistic has been among the preferred methods for identifying biased items. The statistic's performance in identifying uniform bias in simulated data modeled by producing various levels of difference in the (item difficulty) b-parameter for reference…

This study compared four methods for setting item response time thresholds to differentiate rapid-guessing behavior from solution behavior. Thresholds were either (a) common for all test items, (b) based on item surface features such as the amount of reading required, (c) based on visually inspecting response time frequency distributions, or (d)…

The Mantel-Haenszel (MH) procedure has become one of the most popular procedures for detecting differential item functioning (DIF). One of the most troublesome criticisms of this procedure is that while detection rates for uniform DIF are very good, the procedure is not sensitive to non-uniform DIF. In this study, examinee responses were generated…

An analysis-of-covariance methodology was used to investigate whether there were population differences between tryout and operational Rasch item b-values relative to differences between pairs of item response theory (IRT) b-values from consecutive operational item administrations. This methodology allowed the evaluation of whether any such…

The performance of the following four methodologies for assessing unidimensionality was examined: (1) DIMTEST; (2) the approach of P. W. Holland and P. R. Rosenbaum; (3) linear factor analysis; and (4) non-linear factor analysis. Each method is examined and compared with other methods using simulated data sets and real data sets. Seven data sets,…

This paper explores the effectiveness of the Mantel-Haenszel (MH) statistic in detecting differentially functioning test items when the internal criterion is varied. Using a data set from the 1982 statewide administration of a 150-item life skills examination (the New Mexico High School Proficiency Examination), a randomly selected sample of 1,000…

A computerized adaptive test (CAT) based on the nominal response model (NR CAT) was implemented, and the performance of the NR CAT and a CAT based on the three-parameter logistic model was compared. The NR CAT produced trait estimates comparable to those of the three-parameter test. (SLD)

To investigate the psychometric feasibility of replacing a paper-and-pencil licensing examination with a computer-administered test, a validity study was conducted. The computer-administered test (Cadm) was a common set of items for all test takers, distinct from computerized adaptive testing, in which test takers receive items appropriate to…

Intellectual abilities were measured for 217 German and 205 American college students using tests (in the subjects' native languages) in which equivalence was established by an item-response theory-based differential-item-functioning (DIF) analysis. Comparisons between groups were not the same before and after removal of DIF items. (SLD)

One important and promising application of item response theory (IRT) is computerized adaptive testing (CAT). The implementation of a nominal response model-based CAT (NRCAT) was studied. Item pool characteristics for the NRCAT as well as the comparative performance of the NRCAT and a CAT based on the three-parameter logistic (3PL) model were…

A two-stage testing strategy is one method of adapting the difficulty of a test to an individual's ability level in an effort to achieve more precise measurement. A routing test provides an initial estimate of ability level, and a second-stage measurement test then evaluates the examinee further. The measurement accuracy and efficiency of item…

The exact and closed-interval area measures for detecting differential item functioning are compared for actual data from 1,000 African-American and 1,000 white college students taking a vocabulary test with items intentionally constructed to favor 1 set of examinees. No real differences in detection of biased items were found. (SLD)