Handedness in deaf and normal children.

The rates of left-handedness were compared in 94 deaf and 104 normal children to test whether the rate of left-handedness is higher in children with congenital deafness than normals. Hand preference was assessed using "Edinburg Handedness Inventory." Of 104 normal children, 94 (90.39%) were right-handed and 10 (9.61%) were left-handed. Of 91 deaf children, 72 (79.12%) were right-handed and 19 (20.88%) were left-handed. The difference between the incidences of left-handedness between these groups was statistically significant: deaf children were more left-handed and less right-handed than their normal counterparts. These results suggest that the right-ear advantage in the normal population does not develop during early fetal period in congenitally deaf children.