BACKGROUND Although the Functional Assessment of Cancer Therapy--General questionnaire (FACT-G) has been validated few studies have explored the factor structure of the instrument, in particular using non-sample dependent measurement techniques, such as Rasch Models. Furthermore, few studies have explored the relationship between item fit to the Rasch Model and clinical utility. The aim of this...

Caussinus’s loglinear model of quasi symmetry has interesting connections with models for within-subject effects with repeated categorical measurement. For binary responses, Tjur (1982) showed that estimates of main effect parameters in the quasi-symmetry model are also conditional maximum likelihood estimates of item parameters for a fixed effects treatment of subject terms in the Rasch item r...

Background and aims The Bergen Social Media Addiction Scale (BSMAS), a six-item self-report scale that is a brief and effective psychometric instrument for assessing at-risk social media addiction on the Internet. However, its psychometric properties in Persian have never been examined and no studies have applied Rasch analysis for the psychometric testing. This study aimed to verify the constr...

In this study, construct validity of 2 pain behaviour observation measurement instruments for young children aged 1 to 56 months (mean age was 20 months) with burns is assessed by using Rasch analysis. The Rasch model, wherein data should meet the model expectations, assumes that an instrument measures one unidimensional construct, and focuses on the items of measurement instruments. The Pain O...

This paper presents a test for measuring the C language knowledge of a software developer. The test was grounded with a web experiment comprising 151 participants. Their background ranged from pupils to professional developers. The resulting variable is based on the Rasch Model. Therefore single questions as well as the entire test could be assessed. The paper describes the experiment, the appl...

This essay describes Rasch analysis psychometric techniques and how such techniques can be used by life sciences education researchers to guide the development and use of surveys and tests. Specifically, Rasch techniques can be used to document and evaluate the measurement functioning of such instruments. Rasch techniques also allow researchers to construct "Wright maps" to explain the meaning ...

Data from the 1996 Course Experience Questionnaire (CEQ) were analysed using the Rasch measurement model. This analysis indicates that 17 of the 25 CEQ items fit a unitary scale that measures course quality as perceived by graduates. Graduates are located on the interval measurement scale produced in the Rasch analysis. The interval nature of the scale renders the graduates’ scores amenable to ...

Rasch mixture models can be a useful tool when checking the assumption of measurement invariance for a single Rasch model. They provide advantages compared to manifest DIF tests when the DIF groups are only weakly correlated with the manifest covariates available. Unlike in single Rasch models, estimation of Rasch mixture models is sensitive to the specification of the ability distribution even...

CONTEXT High-quality fatigue rating scales are needed to advance the understanding of fatigue and determine the efficacy of interventions. Several fatigue scales are used in Parkinson's disease, but few have been tested using modern psychometric methodology (Rasch analysis). OBJECTIVES To examine the measurement properties of the generic Functional Assessment of Chronic Illness Therapy-Fatigu...