Table 1.

Characteristics for the Nap, No Nap, and Control Groups.

	Nap group		No nap group		Control group		F / χ2	p
	Mean	SD	Mean	SD	Mean	SD
N	29	-	28	-	26	-	-	-
Age, years	16.75	0.94	16.91	1.14	16.81	1.17	0.14	0.87
Gender (% males)	55.20	-	57.10	-	42.30	-	1.39	0.50
Body mass index	20.19	2.71	20.92	2.77	20.38	2.55	0.57	0.57
Caffeinated drinks per day	0.81	0.75	0.75	0.91	0.54	0.79	0.82	0.44
Morningness-Eveningness Questionnaire score	52.62	7.27	50.25	7.66	49.96	7.15	1.11	0.34
Epworth Sleepiness Scale score	6.57	2.86	6.52	2.57	6.19	3.57	0.12	0.88
Chronic Sleep Reduction Questionnaire
Total score	33.62	4.12	34.21	5.07	33.81	5.13	0.11	.89
Shortness of sleep	12.83	1.75	12.36	2.31	12.50	2.30	0.37	.70
Irritation	6.28	1.51	6.36	1.50	6.77	1.58	0.81	.45
Loss of energy	7.21	1.35	7.93	2.05	7.00	1.65	2.24	.11
Sleepiness	7.31	1.23	7.57	1.60	7.54	1.75	0.25	.78
Pittsburgh Sleep Quality Index (term time)
TIB on weekdays, hr	6.50	0.90	6.52	0.72	5.94	1.14	3.36	.04
TIB on weekends, hr	9.05	1.07	8.76	1.09	9.20	1.30	1.02	.36
TST on weekdays, hr	6.05	0.91	6.13	0.73	5.78	1.15	1.02	.36
TST on weekends, hr	8.57	1.03	8.40	1.02	9.04	1.30	2.38	.10
Global score	5.28	1.89	5.39	2.25	4.58	2.58	1.03	.36
Actigraphy (term time)
TIB on weekdays, hr	6.20	1.03	6.44	0.99	6.09	0.85	0.87	.42
TIB on weekends, hr	8.18	0.82	8.15	0.70	8.45	1.25	0.80	.45
TST on weekdays, hr	5.43	0.95	5.69	0.89	5.37	0.73	1.00	.37
TST on weekends, hr	7.31	0.86	7.23	0.63	7.53	1.14	0.77	.47
Sleep efficiency (%)	88.00	4.98	88.51	4.10	88.45	4.66	0.10	.90

Abbreviations: SD, standard deviation; TIB, time in bed; TST, total sleep time.