The dimensionality of the Edinburgh Handedness Inventory: An analysis with models of the item response theory

Abstract

Handedness is frequently measured with sum scores or quotients taken from laterality questionnaires like the Edinburgh Handedness Inventory (EHI). In classical test theory such data cannot be used to confirm either the unidimensionality (i.e., quantitative differentiation with the poles left-handed and right-handed) or multidimensionality (i.e., typological differentiation between left-, right-, and mixed-handers) of this personal characteristic. This study uses item response theory models to test the construct validity of the EHI on an item level in order to gather empirical support for the differentiation of handedness as well as the appropriateness of the items and the response format. The EHI was given to 540 participants (303 male and 237 female) aged 17-37 years. Results of mixed-Rasch analyses revealed that the best model was a two-class solution; that is, left- and right-handers (types) with quantitative differences between persons. Hence, unlike earlier model tests, this rejects both the unidimensionality of the handedness construct and the need to consider so-called mixed-handers. It is proposed that mixed-Rasch analyses should be applied more frequently to test the construct validity of other as well as more extensive handedness questionnaires.

The rubber hand illusion in complex regional pain syndrome: Preserved ability to integrate a rubber hand indicates intact multisensory integration ☆

“…The Edinburgh Handedness Inventory is a well-established questionnaire to assess handedness [44]. The validated German version was used to assess handedness in all participants [5,44]. The questionnaire indicates handedness by means of a laterality quotient (LQ), ranging from À100 to +100.…”

On the other hand: including left-handers in cognitive neuroscience and neurogenetics

“…For example, the widely used Edinburgh Handedness Inventory, which is often administered as a self-report questionnaire, assesses hand preference for a range of common manual tasks 4 . The inventory includes an indication of the strength of hand preference for each task and can be updated to include only items that are culturally relevant to a particular target population 5,6 . In the general population, the resulting laterality index -a measure of the direction and strength of preference across all items -is bimodal 4 ; in other words, the majority of subjects score towards one or the other extreme of the distribution for left-or right-handedness.…”

Writing with non-dominant hand: left-handers perform better with the right hand than right handers with the left

“…Participants' handedness was determined by completing a modified Edinburgh Questionnaire (Büsch et al 2010). This questionnaire referred to 14 activities.…”

“…However, Büsch et al (2010) found that there should be an increase in the number of questions asked to determine handedness, with emphasis on those questions that ask about unequivocally lateralized behaviour.…”