Table 3.

Average Circadian Variables at Typical Sleep and Sleep Extension by Chronotype

				P-values
	Model-Estimated Means (95% CI)			Comparison by Sleep Condition		Comparison by Chronotype
Outcome	Chronotype	Typical Sleep	Sleep Extension	Morning/ Intermediate	Evening	Typical Sleep	Sleep Extension
Dim light melatonin onset (DLMOn; clock time)	Morning/ Intermediate	20:33 (19:34, 21:32)	20:13 (19:16, 21:10)	0.497	0.112	0.539	0.969
	Evening	20:58 (20:08, 21:47)	20:14 (19:23, 21:05)
Dim light melatonin offset (DLMOff; clock time)	Morning/ Intermediate	09:02 (08:06, 09:59)	08:28 (07:38, 09:17)	0.248	0.727	0.120	0.008
	Evening	10:00 (09:17, 10:43)	10:09 (09:21, 10:57)
Phase angle between DLMOn and sleep onset (hours)	Morning/ Intermediate	3.9 (2.98, 4.83)	2.67 (1.78, 3.57)	0.020	0.504	0.938	0.154
	Evening	3.86 (3.08, 4.63)	3.56 (2.76, 4.36)
Phase angle between DLMOn and sleep offset (hours)	Morning/ Intermediate	10.14 (9.15, 11.13)	10.61 (9.66, 11.57)	0.427	0.021	0.771	0.351
	Evening	9.95 (9.12, 10.78)	11.23 (10.37, 12.09)
Phase angle between DLMOff and sleep offset (hours)	Morning/ Intermediate	2.41 (1.27, 3.56)	1.61 (0.59, 2.63)	0.154	0.950	0.418	0.066
	Evening	3.02 (2.15, 3.89)	2.99 (2.02, 3.96)
Duration of melatonin Secretion (hours)	Morning/ Intermediate	12.62 (10.98, 14.26)	12.31 (10.99, 13.63)	0.732	0.379	0.764	0.186
	Evening	12.93 (11.79, 14.07)	13.69 (12.19, 15.19)