Polish version of the reduced Morningness–Eveningness Questionnaire

The aim of this study was to develop a Polish version of the reduced Morningness–Eveningness Questionnaire (rMEQ). The sample consisted of 1191 university students (52% females) aged 18–24 years (M = 21.46; SD = 1.49). The Polish version of rMEQ resulted in four items, whose numbers in the original Horne and Östberg Morningness–Eveningness Questionnaire (MEQ) were 1, 4, 9, 19. Cronbach's α coefficient was .732, and the inter-item correlations ranged between .396 and .452. Based on the eigenvalue-greater-than-one criterion, a one factor was excluded which explained 56% of variance and had eigenvalue of 2.258. The correlation between Polish versions of rMEQ and MEQ was .89, and based on the two questionnaires separately, 81% of participants were categorised into the same chronotype group. Age and gender were not related to rMEQ and MEQ scores.