The Pen Is Not Always Mightier: Different Ways of Measuring Handedness With the Edinburgh Handedness Inventory Yield Different Handedness Conclusions

Abstract

Although consistency of handedness (the strength of dominant hand preference) is increasingly recognized as an important individual difference, there are questions about how to best measure it. A recent meta-analysis showed that researchers have often failed to report details of responses and response formats to handedness test items. In addition to measuring handedness direction (i.e., left versus right handedness), there can be utility to dichotomizing the Edinburgh Handedness Inventory (EHI) into consistent and inconsistent dominant handedness, despite controversy over the best means of doing so. In this study, we performed a discriminant function analysis of EHI items to determine which items best predicted handedness consistency versus handedness direction. Although the same discriminant function accounted for most of the variance for both dependent measures, writing and drawing EHI items were the strongest predictors of handedness direction and combing and opening jars items were the strongest predictors of handedness consistency. As different items on the EHI predicted these different handedness dimensions, we discuss the implications of dichotomizing EHI items into both relevant dimensions for both biological and environmental theories of the basis of handedness and for future handedness research.

Memory Effects of Manipulating Text Column Width: Eye-Movement Induced Attentional Processes Interfere With Prose Encoding Among Consistent Handers

“…Specifically, consistent handers showed a one factor solution, while inconsistent handers showed a two factor solution, suggesting that handedness is more complicated for inconsistent handers. When classifying participants into consistent versus inconsistent handedness through discriminant function analysis, those EHI items that loaded onto the second factor were the items that discriminated between consistent and inconsistent handers (Prichard et al., 2020). Thus, a median split on the EDI is an effective handedness consistency classification system.…”

Robot-Assisted Training to Improve Proprioception of Wrist

“…Twelve right-handed subjects (age 23.9±1.6 years, 5 females, 7 males) recruited from local universities with no history of neuromuscular disease and unfamiliar with the task participated in the study. The handedness of all participants was assessed by the Edinburgh Handedness Inventory [18]. The study was approved by the Institutional Review Committee of Shanghai University of Medicine & Health Sciences (protocol number 2019MQY).…”