Przepiorka, M. AnetaM. AnetaPrzepiorkaBlachnio, AgataAgataBlachnioDr. SIU Yat-fan, NicolsonNicolsonDr. SIU Yat-fan2020-07-102020-07-102019Chronobiology International: The Journal of Biological and Medical Rhythm Research, 2019, vol. 36(8), pp. 1025-1035.0742-05281525-6073http://hdl.handle.net/20.500.11861/5916The main aim of our study was to examine whether there was a relationship between psychological characteristics such as self-efficacy, self-control and chronotype as well as procrastination on the one hand and sleep problems on the other. There were 315 young adults aged between 18 and 27 years (M = 20.57). We used the General Procrastination Scale, the General Self-Efficacy Scale (GSES), Brief Self-Control Scale, the Composite Scale of Morningness (CSM) and the Pittsburgh Sleep Quality Index (PSQI). Our results indicated that low self-efficacy, low self-control and eveningness were positive predictors of procrastination. The reciprocal relationship exists between procrastination and sleep problems. Procrastination positively contributed to sleep problems, whereas sleep problems were a negative predictor of procrastination.enPeer Reviewed Journal Article10.1080/07420528.2019.1607370