Left-handedness and mortality.

We examined mortality associated with handedness in two ways. A simulation using national data suggests that lower mean age at death among left-handed persons, previously offered as evidence of higher mortality, can be explained exclusively by the age distribution of laterality. Second, empiric evidence from a 6-year cohort study of 3774 older adults from East Boston, Massachusetts, demonstrates that left-handedness is not associated with mortality (relative odds = 1.04, 95% confidence interval = 0.79, 1.36).