“…Yet, when using the FFM personality traits with age and gender to predict morningness-eveningness in a multiple regression model, found that only three personality traits-Openness, Conscientiousness, and Extraversion-remained significant predictors of morningnesseveningness. Thus, based on this and other studies that have demonstrated the importance of gender, age, and education level in chronotype (e.g., Barclay, Eley, Buysse, Archer, & Gregory, 2010;Paine, Gander, & Travier, 2006;Walker, Kribs, Christopher, Shewach, & Wieth, 2014), and personality traits (e.g., McCrae et al, 2004;Schmitt, Realo, Voracek, & Allik, 2008), we will adjust our analyses for these demographic variables. Given that time of year has a significant effect on the epidemiological variation in sleep duration (Allebrandt et al, 2014;Randler & Rahafar, 2017), we will also control for the effect of seasonal variation on chronotype.…”