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...

BACKGROUND Depression and anxiety are two common normal responses to a chronic disease such as glaucoma. This study analysed the measurement properties of the depression screening instrument - Patient Health Questionnaire-9 (PHQ-9) using Rasch analysis to determine if it can be used as a measure. METHODS In this hospital-based cross-sectional study, the PHQ-9 was administered to primary glauc...

PURPOSE Both the long form visual functioning scale (LFVFS(39)) and visual functioning scale (VFS) are measures of visual functioning (VF) that represent the Rasch-scaled versions of the NEI-VFQ(39) and the Indian vision function questionnaire (IND-VFQ), respectively. The objectives of this study were to investigate if the 15-item LFVFS(39) and 13-item VFS of the IND-VFQ meet the assumptions of...

OBJECTIVE To build a new activity-based, "bed to community", aetiology-independent measure of balance within the neurological rehabilitation setting by merging some existing scales. METHODS Balance scales were selected using a conceptual framework and subsequently administered to a convenience sample of adult patients with balance problems due to different neurological aetiologies. Data were ...

People with chronic conditions, such as epilepsy, are at a high risk for depression; however depression is often under-recognized and undertreated. Depression scales, including one specific to people with epilepsy, have been used for screening in this population, although none have been assessed with Rasch measurement theory. This study used Rasch analyses in order to evaluate and compare the p...

BACKGROUND There is currently no interval-level measure of foot-related disability and this has hampered research in this area. The Manchester Foot Pain and Disability Index (FPDI) could potentially fill this gap. OBJECTIVE To assess the fit of the three subscales (function, pain, appearance) of the FPDI to the Rasch unidimensional measurement model in order to form interval-level scores. M...