Table 2. Characteristics of children affected by the 2011 Japan Earthquake and Tsunami.

Items			After 8 months			After 20 months
			N = 11,639			N = 10,597
Gender	Male		5939		(51.0%)	5302	(50.0%)
	Female		5700		(49.0%)	5295	(50.0%)
Age at the time of the disaster (y) (Mean)			10.9		(SD = 2.7)	10.9	(SD = 2.7)
PTSSC-15 score (Mean)			20.5		(SD = 14.5)	18.8	(SD = 14.0)
Sleep duration on weekdays (Mean)			8.4(h)		(SD = 1.3)	8.5(h)	(SD = 1.2)
Sleep duration on holidays (Mean)			9.0(h)		(SD = 1.4)	9.2 (h)	(SD = 1.3)
Breakfast consumption		yes	10673		(91.7%)	9928	(93.7%)
		no	827		(7.1%)	645	(6.1%)
		unknown	139		(1.2%)	24	(0.2%)