Right-handed pupils score higher in tests, says the study
Left-handed pupils do less well in tests than their right-handed peers, a study from Bristol University suggests.
Researchers based their findings on national curriculum test results (Sats) and IQ tests of over 10,000 children.
The study found the gap between left and right-handed pupils did not lessen with age - the gap was still evident in Key Stage 3 tests sat at 14 years.
The study also identified slow development in "mixed-handed" pupils, where neither hand is dominant.
This phenomenon was found to be a particular problem in girls.
"Our results suggest that schools could use mixed-handedness as a marker for children who are likely to need greater intervention," the report said.
"As tests for mixed-handedness are simple to administer, they would be a cheap way of identifying children who otherwise might slip behind their peers."
Children of the 90s
The researchers wanted to establish whether being left-handed was associated with differential cognitive development.
Using data from Bristol University which tracked children born in the 1990s, the researchers examined pupils' performance in an IQ test and in Key Stage 1, 2 and 3 tests, taken at age seven, 11 and 14 respectively.
The researchers say the results mean they can rule out other factors that might have caused a gap in cognitive development, such as a poorer home background, family size and birth weight.
The study was funded by the Economic and Social Research Council.