Age and gender differences in morningness-eveningness in Turkish adolescents and young adults

Abstract

The aim of this study was to analyze gender and age differences in chronotype preference in a Turkish sample using the Composite Scale of Morningness. Four thousand four hundred and twenty three participants were randomly sampled from students in Turkey. Ages ranged from 11 to 23 and the average age was 16.39 years. There was a significant influence of age and gender. After controlling for age, girls were more morning oriented with one exception: At the age of 16 years, girls had a higher evening orientation than boys, while at the age of 13, 17, and 19 boys showed higher eveningness. Turkish girls become morning oriented from the early age of 15 years onwards, while boys reported their peak of eveningness at the age of 19. This is fascinating, since it is the earliest age reported for a turn to morningness in girls compared to previous studies. Interestingly, girls perform a second turn towards eveningness between the ages of 17 and 19. Cultural background may imprint the early shift back to morningness in girls, since Turkish parenting styles are different for boys and girls with a more authoritarian parenting style for girls, e.g. girls help their mothers. Later on, enrolment in university might foster more independence and promote the drift back to eveningness.