Girls are not as good as boys in playing soccer, nor are they clued into cars, but they know how to dance better and stay away from mischief -- these are some pet prejudices cultivated by everyone from childhood, but a new study provides a solution to prevent such bias.

The study was carried out by Andreas Beelmann, professor of psychology at the Friedrich Schiller University Jena (Germany).

Jena psychologists Tobias Raabe and Beelmann, say the development of prejudice increases steadily at pre-school age and reaches its highest level between five and seven years of age, the journal Child Development reported.

The effect declines with increasing age. Therefore, they reckon this age as the ideal time to start prevention programmes against prejudice.

"Prevention starting at that age supports the normal course of development," said Beelmann, according to a university statement.