Lifespan trends of side bias in India.

This study examines the (a) lifespan trends, (b) theoretical propositions, (c) factor structure, and (d) congruency among different forms of side bias in an Indian sample (N=3474) using the preference measure of handedness, footedness, eyedness, and earedness. An increase in dextral preference was found in all indices of side bias with increasing age. There were no left-handers among the oldest adults. This trend was not found for footedness, eyedness, and earedness. Females were more right sided than males on all indices of side bias except handedness. The preferential use of limbs stabilised during young adulthood but eye and ear preference did not. Three factors were underlying the formation and maintenance of four forms of side bias. Handedness and footedness constituted one factor, and eyedness and earedness were independent separate factors. The first two had highest association and the last two had lowest congruency.