The Edinburgh Handedness Inventory (EHI) is the most widely used standardized assessment for determining hand preference and the degree of handedness in research and clinical settings. Originally developed by Oldfield (1971) as a 20-item questionnaire, the 10-item short form (EHI-10) provides an efficient yet comprehensive evaluation of hand dominance patterns for common daily activities.
With thousands of citations across neuroscience, psychology, and medical literature, the EHI has become the international standard for handedness assessment, valued for its simplicity, reliability, and ability to capture both the direction and strength of hand preference.
Understanding Handedness as Neural Organization
Handedness is a fundamental aspect of human neurological organization, reflecting underlying brain lateralization patterns. It represents the preferential use of one hand over the other for skilled motor activities, which corresponds to contralateral hemispheric dominance in the brain.
Population distribution:
Approximately 90% of people are right-handed
8-10% are left-handed
1-2% show mixed or ambidextrous patterns
Understanding an individual’s handedness is crucial for neuroscience research, clinical neuropsychology, and studies investigating brain-behavior relationships, as it provides insights into hemispheric specialization for language, motor control, and other cognitive functions.
Importantly, handedness is not simply a binary trait but exists on a continuum from strong left to strong right preference, with varying degrees of consistency across different activities.
Theoretical Foundation
The EHI is grounded in theories of cerebral lateralization and functional hemispheric asymmetry. The scale was developed based on observations that hand preference reflects the dominant motor cortex, which is typically contralateral to the preferred hand.
For most right-handed individuals, the left hemisphere is dominant for both motor control and language, while left-handed individuals show more variable patterns of lateralization. This relationship between handedness and brain organization makes the EHI valuable not just for assessing motor preference, but as a window into broader patterns of neural organization.
The inventory’s design recognizes that handedness is not uniform across all activities—some tasks may show stronger preference than others, and individuals may demonstrate mixed patterns. The laterality quotient (LQ) calculation allows researchers to quantify both:
Direction: Left vs. right hand preference
Strength: Strong, mixed, or ambidextrous patterns
This dimensional approach has proven particularly valuable in neuroimaging research, where handedness serves as a predictor of language lateralization and other functional brain asymmetries.
🧠 Research Essential: The EHI is considered the gold standard for handedness assessment in neuroscience research, cited in thousands of studies investigating brain lateralization and cognitive function.
Key Features
Assessment Characteristics
10 common activities representing diverse motor functions
2-3 minutes completion time
Ages 6+ through adult (reading ability required)
Laterality quotient (LQ) calculation on -100 to +100 scale
Free for research use worldwide
Hand Preference Dimensions Assessed
Fine motor control – Writing, drawing, precision tasks
Tool manipulation – Scissors, knife, implements
Gross motor actions – Throwing, sweeping, strength activities
Bimanual coordination – Tasks requiring two-handed control
Preference strength – Strong vs. mixed hand dominance patterns
Consistency – Stable vs. variable hand use across activities
Research and Clinical Applications
Pre-surgical planning – Language lateralization for brain procedures
Neuroscience research – Brain lateralization and hemispheric specialization studies
Neuropsychological assessment – Baseline measurement for cognitive testing
Neuroimaging studies – Control variable in fMRI, EEG, and PET research
Language lateralization – Predicting hemispheric dominance for language
Clinical neuropsychology – Evaluation following brain injury or stroke
Developmental research – Motor development and lateralization emergence
Cross-cultural neuroscience – Handedness prevalence across populations
Copyright and Usage Responsibility: Check that you have the proper rights and permissions to use this assessment tool in your research. This may include purchasing appropriate licenses, obtaining permissions from authors/copyright holders, or ensuring your usage falls within fair use guidelines.
The Edinburgh Handedness Inventory is free for research and clinical use. The original scale was published in an academic journal without commercial restrictions. Researchers and clinicians may use the measure without seeking specific permission, though proper citation of the original work is required.
Proper Attribution: When using or referencing this scale, cite the original development:
Oldfield, R. C. (1971). The assessment and analysis of handedness: The Edinburgh inventory. Neuropsychologia, 9(1), 97-113.
For the 10-item short form specifically, also cite:
Veale, J. F. (2014). Edinburgh Handedness Inventory – Short Form: A revised version based on confirmatory factor analysis. Laterality, 19(2), 164-177.
Oldfield, R. C. (1971). The assessment and analysis of handedness: The Edinburgh inventory. Neuropsychologia, 9(1), 97-113.
10-Item Short Form Validation:
Veale, J. F. (2014). Edinburgh Handedness Inventory – Short Form: A revised version based on confirmatory factor analysis. Laterality, 19(2), 164-177.
Major Reviews and Meta-Analyses:
Papadatou-Pastou, M., Ntolka, E., Schmitz, J., Martin, M., Munafò, M. R., Ocklenburg, S., & Paracchini, S. (2020). Human handedness: A meta-analysis. Psychological Bulletin, 146(6), 481-524.
McManus, I. C., Davison, A., & Armour, J. A. (2013). Multilocus genetic models of handedness closely resemble single-locus models in explaining family data and are compatible with genome-wide association studies. Annals of the New York Academy of Sciences, 1288(1), 48-58.
Neuroimaging and Brain Lateralization:
Knecht, S., Dräger, B., Deppe, M., Bobe, L., Lohmann, H., Flöel, A., Ringelstein, E. B., & Henningsen, H. (2000). Handedness and hemispheric language dominance in healthy humans. Brain, 123(12), 2512-2518.
Amunts, K., Schlaug, G., Schleicher, A., Steinmetz, H., Dabringhaus, A., Roland, P. E., & Zilles, K. (1996). Asymmetry in the human motor cortex and handedness. NeuroImage, 4(3), 216-222.
Genetics and Development:
McManus, I. C., Moore, J., Freegard, M., & Rawles, R. (2010). Science in the making: Right hand, left hand. III: Estimating historical rates of left-handedness. Laterality, 15(1-2), 186-208.
Medland, S. E., Duffy, D. L., Wright, M. J., Geffen, G. M., Hay, D. A., Levy, F., van-Beijsterveldt, C. E., Willemsen, G., Townsend, G. C., White, V., Hewitt, A. W., Mackey, D. A., Bailey, J. M., Slutske, W. S., Nyholt, D. R., Treloar, S. A., Martin, N. G., & Boomsma, D. I. (2009). Genetic influences on handedness: Data from 25,732 Australian and Dutch twin families. Neuropsychologia, 47(2), 330-337.
Clinical Applications:
Bishop, D. V. (1990). Handedness and developmental disorder. Blackwell Scientific Publications.
Markou, P., Ahtam, B., & Papadatou-Pastou, M. (2017). Elevated levels of atypical handedness in autism: Meta-analyses. Neuropsychology Review, 27(3), 258-283.
