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Right or wrong? On the difficult relationship between epidemiologists and handedness
1Epidemiology Branch, NIEHS, NIH, HHS, Research Triangle Park, North Carolina 27709, USA. bassoo2@niehs.nih.gov
Epidemiology (Cambridge, Mass.)
|February 16, 2007
Summary
Research suggests left-handedness may not be linked to a shorter lifespan. Methodological issues in handedness studies, including heterogeneity and publication bias, undermine the credibility of claims linking sinistrality to reduced longevity.
Area of Science:
- Neuroscience
- Epidemiology
- Human Biology
Background:
- The hypothesis that sinistrality (left-handedness) is associated with a reduced lifespan stems from its declining prevalence with age.
- This hypothesis posits that left-handedness may result from developmental insults or neurological impairments.
Discussion:
- The scientific literature on handedness faces significant methodological challenges.
- These include the ease of data collection without prior hypotheses, failure to account for variations among left-handers (heterogeneity), and a tendency for positive results to be preferentially published (publication bias).
Key Insights:
- These methodological flaws collectively reduce the credibility of research linking left-handedness to decreased longevity.
- The observed decline in left-handedness with age may not necessarily indicate a shorter lifespan for left-handers.
Outlook:
- Future research on handedness requires rigorous methodologies to address heterogeneity and publication bias.
- Establishing a definitive link between sinistrality and lifespan necessitates overcoming the current limitations in the field.
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