Abstract
Psychometric properties of Morningness Composite and Preferences Scales. Morningness, or the preferences by morning or evening activities is an individual difference in circadian rhythms. Several selfevaluation instruments have been developed for identifying the individual circadian typology. Aim of the present work is analyze the psychometric properties of two scales of morningness. The Morningness Composite and the Early/Late Preferences Scales are studied in a group of 203 undergraduates between 19 and 30 years old. Results reveals a satisfactory level of reliability and the one-dimensionality of morningness is discussed.
