TABLE 1.

Sample characteristics.

	n	Mean ± SD	Range
Age	31	21.1 ± 1.2	18 – 22
Sex	31	12 males / 19 females
Racial identity/ethnicity	31	23 White, 3 Black (full or biracial), 5 Asian-American (full or biracial); 2 Hispanic
Alcohol use at screening (TLFB)
Total drinks over past 30 days	31	30.5 ± 30.6	7 – 136
Binge days (5+/4+ drinks) over past 30 days	31	3.2 ± 3.6	0 – 15
Alcohol use during the study weekend (EMA)
Total drinks over Friday and Saturday	24	4.8 ± 4.4	0 – 12
Actigraphy – midsleep
Tuesday/Wednesday pre-DLMO	28	4:53 ± 1:17	2:49 – 7:44
Friday/Saturday pre-DLMO	28	5:25 ± 1:01	3:03 – 8:45
Actigraphy – total sleep time (TST)
Thursday DLMO night	25	6 h 23 m ± 1 h 14 m	3 h 10 m – 8 h 40 m
Sunday DLMO night	28	6 h 32 m ± 1 h 3 m	4 h 5 m – 8 h 13 m
DLMO – Thursday	26	22:09 ± 1:32	18:36 – 01:44
DLMO – Sunday	27	22:08 ± 1:30	18:53 – 01:57
DLMO-midsleep phase angle (hours)
Thu DLMO-Tuesday/Wednesday midsleep	24	6.75 ± 1.47	4.37 – 9.44
Sun DLMO-Friday/Saturday midsleep	25	7.24 ± 1.68	4.45 – 10.76
Social jet lag-midsleep (Friday/Saturday– Tuesday/Wednesday; hours)	26	0.53 ± 1.33	−1.14 – 4.84
Social jet lag-DLMO (Sunday–Thursday; hours)	26	0.04 ± 0.82	−1.40 – 1.79

TLFB, timeline follow back; EMA, ecological momentary assessment; DLMO, dim light melatonin onset.