Two measures of laterality in handedness: the Edinburgh Handedness Inventory and the Purdue Pegboard test of manual dexterity.

This study investigated the relationship between a paper-and-pencil measure of laterality in handedness, the Edinburgh Handedness Inventory, and a test of manual dexterity, the Purdue Pegboard test. Individuals of extreme handedness based on the Edinburgh Handedness Inventory (laterality Quotients of +90 to +100 and -100 and +54; 50 each) were recruited to complete the Purdue Pegboard test of manual dexterity. Subjects in the sinistral group had significantly smaller mean discrepancy scores in performance between their hands [t80 = 5.12, p = .0001] and much greater variance in performance than dextral subjects (F1,98 = 2.85, p = .0001). These findings suggest that paper-and-pencil measures of lateral preference for handedness may not identify proficiency of subgroups within a sinistral group.