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PM-Left-handed Study,0383
^British study indicates left-handers don't die earlier
^By EMMA ROSS= ^Associated Press Writer=
LONDON (AP) Left-handed people don't necessarily die any younger than right-handers, says new research that runs counter to what some studies have suggested.
In a nine-year study, Dr. Simon Ellis and his colleagues at Keele University in England examined the link between left-handedness and the risk of dying earlier using 6,049 people ranging in age from 15 to 70.
``Handedness did not make a significant contribution to the outcome of death,'' concluded the study, published today in this week's issue of The Lancet, a British medical journal.
The question of whether lefties die younger is controversial. Several studies have suggested a connection, but others have shown no link.
One theory suggests that older age groups contain fewer left-handers not because they die earlier, but because many in the older generation were forced as children to become right-handed, whereas children today are less likely to be pressured into switching.
Researchers found in 1991 that the proportion of left-handers decreases with age, dropping from 13 percent in 20-year-olds to less than 1 percent in 80-year-olds.
That led scientists to suggest that left-handedness may be associated with a shorter lifespan, perhaps because southpaws are less adapted to survival and thus more prone to immune disease or accidents.
One study suggested that right-handed people live about nine years longer than left-handers.
But some researchers, such as Richard Peto, professor of medical statistics and epidemiology at Oxford University, dispute those conclusions.
``I haven't seen any competent studies showing a link,'' said Peto, who was not involved in the Keele University study. ``You've got to adjust for age.''
In the study, the left-handed group was younger than the right-handed group, but the analysis accounted for the effect of age.
The investigators initially received 6,097 correctly completed questionnaires to their initial mailing to people between 15 and 70 years old. Nine years later, they attempted to trace the respondents: Forty-eight could not be traced, 387 had died and the remaining 5,662 were known to be alive.


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