About the research
You are a left-handed girl. Does that predict better grades than a right-handed boy?
Stories and superstitions about ‘lefties’ have been around for generations. In recent years, there has been a special curiosity about whether there are links between handedness and academic abilities. In this study the authors investigated the effects of gender, writing hand, relative hand skill, and UK region on mathematics and reading test scores from pupils across Britain.
To do this, the researchers analysed responses from 11-year olds included in the National Child Development Study to find associations between cognitive ability (reading and maths scores) and a range of factors including handedness and gender.
Their findings indicate that children who write with one hand, while being better skilled with the other hand, performed worse in both the reading and maths tests than children who write with the hand which has the most hand skill, irrespective of whether the child was left- or right-handed.
This suggests that handedness tasks should be considered in conjunction with a measure of hand skill in future studies of investigating cognitive ability and handedness.
Methodology
The authors applied a multivariate linear mixed-effects model with reading and transformed maths scores from 11-year-olds in sweep 2 of the NCDS childhood dataset as the two outcomes. A multivariate model was considered to jointly analyse reading and maths scores as a bivariate outcome, and the model included both fixed and random factors (hence the name ‘mixed-effects’). Explanatory variables/fixed factors included:
- writing hand
- gender
- superior hand (the hand with greatest skill)
- relative hand skill
- UK region
Relative hand skill was calculated from n1601 and n1605 (relating to the box-ticking measurement of handedness). UK region was reduced from 11 in n2region to four.
The researchers also included a clustering variable, local authority from the National Child Development Study dataset SN 5744, which is regarded as the random factor of the model.
Publications
The study was published as The effect of handedness on academic ability: A multivariate linear mixed model approach in the journal Laterality, 2010.