Reliability and validity of the Persian version of the Children's Chronotype Questionnaire in school and preschool-aged children (CCTQ).

Chronotype refers to individual differences in the circadian phase that affect a person's biological and psychological functioning. One of the most useful tools for measuring chronotype in children aged 4 - 11 years is the Children's Chronotype Questionnaire (CCTQ). Therefore, due to the importance of measuring chronotype in children and also the lack of a standard scale in Iran, this study aimed to examine the reliability and validity of the Persian version of this questionnaire for children. The participants of this cross-sectional study were 272 Iranian children aged five to eleven years with their parents, selected by convenience sampling method. To collect data, all participants completed the CCTQ and the Children's Sleep Habits Questionnaire (CSHQ), which were examined by the researchers for their construct and concurrent validity. Over a period of three weeks, 50 mothers participated in a test of the test-retest reliability of the CCTQ. During this time, their sleep patterns were monitored using a sleep diary to test for reliability. The Cronbach's alpha of the CCTQ-M/E was 0.71. Test-retest reliability using the Spearman correlation coefficient between two observations with an interval of three weeks was 0.83. The MSFsc index was significantly correlated with M/E, CT, and most of the parent-reported sleep/wake parameters. In addition, the three indicators of the CCTQ were significantly associated with most of the sleep/wake parameters of the sleep diary and the components of the CSHQ. The Persian version of the CCTQ has desirable psychometric properties for the assessment of chronotype in five- to eleven-year-old children.