OBJECTIVE This study has used Item Response Theory (IRT) to examine the psychometric properties of Health-Related Quality-of-Life. METHOD This investigation is a descriptive- analytic study. Subjects were 370 undergraduate students of nursing and midwifery who were selected from Tabriz University of Medical Sciences. All participants were asked to complete the Farsi version of WHOQOL-BREF. Sa...

From October each year to the following May, the Laboratory Centre for Disease Control (LCDC) maintains a program for the national surveillance of influenza. This program is supported by a number of laboratories and provincial and territorial epidemiologists who collaborate by exchanging information on cases, laboratory identifications and outbreaks. During the 1994-1995 season these surveillan...

Past studies of the expression of depression in people of Asian descent have not considered whether observed ethnic differences in somatization or psychologization are a function of differences in the expression of the disorder or of group differences in the degree of depressive symptomatology. In the present study, we carried out χ(2) and Item Response Theory (IRT) analyses to examine ethnic d...

Computerized telephone technology has garnered increasing interest as an assessment tool specifically for the collection of daily, near-contemporaneous self-reports of HIV risk behaviors. In this review, we discuss advantages and recent applications of interactive voice response technology (IVR) to HIV risk behavior research, including feasibility studies, assessment mode comparisons between IV...

BACKGROUND Many continuous item responses (CIRs) are encountered in healthcare settings, but no one uses item response theory's (IRT) probabilistic modeling to present graphical presentations for interpreting CIR results. A computer module that is programmed to deal with CIRs is required. To present a computer module, validate it, and verify its usefulness in dealing with CIR data, and then to ...

BACKGROUND Racism and associated discrimination are pervasive and persistent challenges with multiple cumulative deleterious effects contributing to inequities in various health outcomes. Globally, research over the past decade has shown consistent associations between racism and negative health concerns. Such research confirms that race endures as one of the strongest predictors of poor health...

The aim of this study is to assess the effective measurement range of Ryff's Psychological Well-being scales (PWB). It applies normal ogive item response theory (IRT) methodology using factor analysis procedures for ordinal data based on a limited information estimation approach. The data come from a sample of 1,179 women participating in a midlife follow-up of a national birth cohort study in ...

BACKGROUND Multi-item questionnaires are important instruments for monitoring health in epidemiological longitudinal studies. Mostly sum-scores are used as a summary measure for these multi-item questionnaires. The objective of this study was to show the negative impact of using sum-score based longitudinal data analysis instead of Item Response Theory (IRT)-based plausible values. METHODS In...

Humans and animals time intervals from seconds to minutes with high accuracy but limited precision. Consequently, time-based decisions are inevitably subjected to our endogenous timing uncertainty, and thus require temporal risk assessment. In this study, we tested temporal risk assessment ability of humans when participants had to withhold each subsequent response for a minimum duration to ear...

The growing emphasis on patient-centered care has accelerated the demand for high-quality data from patient-reported outcome (PRO) measures. Traditionally, the development and validation of these measures has been guided by classical test theory. However, item response theory (IRT), an alternate measurement framework, offers promise for addressing practical measurement problems found in health-...