Analysis Suggests Left-Handed People Live Longer
NEW YORK (AP) _ Left-handed people may tend to live longer than right-handers, suggests an analysis of the lifespans of baseball players.
The advantage appeared for southpaws born after 1890, averaging 2.1 years for those born in 1910 and estimated to climb eventually to about 3.73 years, said researcher Max Anderson.
But his conclusions were disputed by another researcher whose previous analysis concluded that left-handed players live shorter lives.
Still another previous analysis of players found no difference in lifespans.
Anderson, a statistics consultant in Vancouver, British Columbia, presents his results in a letter to the editor in Thursday’s issue of the British journal Nature.
He studied the lifespans of 4,479 ballplayers, comparing average longevities of left- versus right-handers born in the same year from 1860 to 1922. The year-by-year approach accounts for increases in life expectancy, he said in a telephone interview.
He found that left-handers born before 1890 tended to live shorter lives than right-handers, with the advantage reversed after that date.
The difference over time may reflect a decline of some unknown factors that had been shortening the lives of left-handers, said Anderson, who is a southpaw.
Anderson’s analysis was criticized by Stanley Coren of the University of British Columbia in Vancouver, co-author of a letter in Nature last year that asserted left-handed ballplayers tended to live shorter lives if they survived past age 33.
Coren’s analysis found virtually no lifespan difference up to that age, but from then on, about 2 percent more right-handers than left-handers survived at each age.
In a telephone interview, Coren noted that Anderson considered only the throwing hand in assigning handedness. Coren’s analysis, done with Diane Halpern of California State University in San Bernardino, focused on players with the same batting and throwing hand.
In that way the study could concentrate on ″pure″ left- and right- handers, rather than players with some degree of ambidexterity, he said. Maybe Anderson’s results reflect a survival advantage from being ambidextrous, he said.
He also said average differences in longevity, which Anderson used, is ″probably not the appropriate statistic″ for analysis.