. Author manuscript; available in PMC: 2020 Apr 1.

Published in final edited form as: Chronobiol Int. 2019 Feb 20;36(4):461–469. doi: 10.1080/07420528.2018.1509079

Table 2.

—Sleep Timing and Duration Descriptive Statistics (n = 3,097)

	Mean	SD
Bedtime
School nights (Sun-Thurs)	22:22	1.13
Weekend nights (Fri-Sat)	00:31	1.91
Wake time
School days (Mon-Fri)	06:20	.85
Weekend days (Sat-Sun)	09:44	1.84
Sleep duration (hrs)
School nights	7.98	1.24
Weekend nights	9.22	2.03
Weekly average^a	8.33	1.17
Social jetlag
Social jetlag (hrs)^b	2.81	1.46
Social jetlag, sleep-corrected (hrs)^c	2.19	1.65

Calculated as [(sleep duration on school nights*5) + (sleep duration on weekend nights*2)] / 7.

Calculated as | midpoint of sleep on weekend nights − midpoint of sleep on school nights | (18).

Calculated as | bedtime on weekend nights − bedtime on school nights | (27)