BACKGROUND The Washington Radiation for In-Stent Restenosis Trial is a double-blinded randomized study evaluating the effects of intracoronary radiation therapy (IRT) in patients with in-stent restenosis (ISR). METHODS AND RESULTS One hundred thirty patients with ISR (100 native coronary and 30 vein grafts) underwent percutaneous transluminal coronary angioplasty, laser ablation, rotational a...

OBJECTIVE To investigate variation in immunoreactive trypsinogen (IRT) concentrations by race, sex, birth weight, and gestational age and their implications for the use of percentile-based cutoffs for cystic fibrosis (CF) newborn screening (NBS) programs. PATIENTS AND METHODS This cross-sectional population-based study of resident infants screened in Michigan investigates associations between...

1. Infrared thermography (IRT) for detecting body temperature is less accurate in women, elderly people, and those with fever. 2. The core temperature significantly but weakly correlates to the IRT temperatures obtained from frontal and lateral of the face, and the forehead. 3. Among the three areas, the forehead IRT temperature showed the largest discrepancy and poorest correlation with the co...

Embedding item response theory (IRT) models within a multilevel modeling framework has been shown by many authors to allow better estimation of the relationships between predictor variables and IRT latent traits (Adams, Wilson, & Wu, 1997). A multilevel IRT model recently proposed by Kamata (1998, 2001) yields the additional benefit of being able to accommodate data that are collected in hierar...

BACKGROUND Although item response theory (IRT) appears to be increasingly used within health care research in general, a comprehensive overview of the frequency and characteristics of IRT analyses within the rheumatic field is lacking. An overview of the use and application of IRT in rheumatology to date may give insight into future research directions and highlight new possibilities for the im...

Recently, several authors have introduced and discussed the advantage of the use of item response theory models (IRT) to construct personality scales and to explore the structure of personality data sets. For example, Waller, Tellegen, McDonald, and Lykken (1996) contrasted the use of IRT to principal factor analysis and Reise and Waller (in press) discussed the choice of an IRT model to analyz...

BACKGROUND Following the severe acute respiratory syndrome (SARS) outbreak, remote-sensing infrared thermography (IRT) has been advocated as a possible means of screening for fever in travelers at airports and border crossings, but its applicability has not been established. We therefore set out to evaluate (1) the feasibility of IRT imaging to identify subjects with fever, and (2) the optimal ...

Linear factor analysis (FA) models can be reliably tested using test statistics based on residual covariances. We show that the same statistics can be used to reliably test the fit of item response theory (IRT) models for ordinal data (under some conditions). Hence, the fit of an FA model and of an IRT model to the same data set can now be compared. When applied to a binary data set, our experi...