Background Multidisciplinary (MD) rehabilitation is an important component of symptomatic
and supportive treatment for Multiple Sclerosis (MS), but evidence base for its effectiveness …

The assumption of local independence is central to all item response theory (IRT) models.
Violations can lead to inflated estimates of reliability and problems with construct validity. For …

The application of the Rasch measurement model in rehabilitation is now well established.
Both its dichotomous and polytomous forms provide for transforming ordinal scales into …

Abstract Purpose The Patient and Observer Scar Assessment Scale (POSAS) is a
questionnaire that was developed to assess scar quality. It consists of two separate six-item …

Physical activity is associated with many benefits, but persons with multiple sclerosis (MS)
are less physically active than the general population. There is a critical need for research …

Psychometric theory requires unidimensionality (ie., scale items should represent a common
latent variable). One advocated approach to test unidimensionality within the Rasch model …

Background The central sensitization inventory (CSI) comprises 25 items and is commonly
used to measure somatic and emotional symptoms related to central sensitization …

Introduction Electronic health (eHealth) strategies are evolving making it important to have
valid scales to assess eHealth and health literacy. Item response theory methods, such as …

Objectives Some argue that generic preference-based measures (PBMs) are not sensitive to
certain disease-specific improvements. To overcome this problem, new condition-specific …

Introduction People with Multiple Sclerosis are known to have a relatively high prevalence of
both anxiety and depression. Studies of the relationship between physical disability and …