Purpose: The Munich Chronotype Questionnaire (MCTQ) assesses actual sleep-wake timing and has advantages compared to prior chronotype questionnaires in that it differentiates sleep-wake patterns between work days and free days and uses corrected mid-sleep time on free days after correcting for accumulated sleep debt over the week to categorize chronotype. The current study, we validated the Korean version of the MCTQ.
Methods: In this study, 310 participants (mean age = 27.09 ± 5.64; 78.1% females) completed the Korean version of the MCTQ.
Results: MCTQ parameters were significantly correlated with MEQ (Morningness-Eveningness Questionnaire) scores (│r│ ≥ 0.48), and test-retest reliability was ≥ 0.72. Cutoff scores of 2.5%, which correlated to 2.36 and 8.57 mid-sleep times in our sample, showed the best convergence with MEQ when categorizing chronotype.
Conclusions: Our study suggests that the MCTQ is a useful questionnaire in assessing chronotype in young adults.
Keywords: Chronotype; Mid-sleep time; Munich Chronotype Questionnaire; Sleep; Validation.