This MEQ consisted of seven questions: three pertaining to sleep offset timing in the morning, one to the peak timing of activity during the daytime and three to sleep onset timing in the evening, which of young children was judged due to the observation in holidays by mostly their mothers (>95%). Answer can be selected from 4 alternatives in each question, and the total of 7 answers can range from 7 (ex- tremely evening-typed) to 28 (extremely morning-typed).
Czech and Japanese versions of an integrated questionnaire (34 questions for children and 11 questions for their parents) which consisted of a morningness-eveningness (M-E) ques- tionnaire (MEQ) originally constructed by Torsvall and Åker- stedt (1980) and an original questionnaire on sleep habits (Ha- rada et al., 1988), video game playing and mental health and were completed in June or November 2007 to avoid the severe summer and winter seasons.