ABOUT THE USE OF THE FAMOUS 'SINGLE PALMAR CREASE' AS A NOTORIOUS MARKER IN HAND DIAGNOSTICS
Ethnic popuations & the Simian Line
In the work 'Hands: The Complete Book of Palmistry' (1985), described Hachiro Asano from Japan statistics which demonstrate that the simian line is more common in Oriental (Asian) populations.
The following percentages are presented as indicative for the occurence of (complete) simian lines in various ethnic populations:
Some of the percentages presented by Asano are also cited (including specific sources) in the work 'Anthropology of crease morphogenesis (1994) by R.S. Bali from India.
Bali also described some statistics on the sexe difference of the simian crease among various populations, which indicate that the presence of a 'complete' simian crease is usually more common seen in men compared to women (compiled from page 322):
But the most detailed study on the occurence of the simian crease in populations (only from Europe) was presented by the frenchman M. Th. de Lestrange (The transverse crease in Europe, 1969).
De Lestrange published a review of 32 historically published studies (from 19 countries), and used 4 selection criteria (study of both sexes, sample size 1000+, no combination of samples, no specific populations) to select those studies who reveal probably the most reliable data. 24 Of the 32 studies were rejected, resulting in a selection 8 studies that met all four criteria.
Six of those 8 studies included both men and women (including studies from France, Greece, The Netherlands, and 3 studies from Germany). The results of these studies for men and women were as follows:
So in general, all large studies from Europe indicate that simian lines are observed almost twice as often in men compared to women.
Asano's study includes also a likewise male-female ratio for the occurence of simian lines in Japan (based on the hands of 3,775 infants and their parents).
What is in 2011 the state of knowledge about how simian lines are related to medical problems? ...more.