. 2019 Apr 24;1(2):226–239. doi: 10.3390/clockssleep1020020

Table 2.

Objective sleep measures (time in bed (TIB), total sleep time (TST), and sleep efficiency (SE)) by shift roster (8- versus 12-h).

	8-h Shift	12-h Shift	Statistic, p-Value, Effect Size
*Day sleep after night shift*
Time in Bed (hours)	(1.34) 5.34	(1.51) 4.59	F_(1,21) = 3.38	p = 0.08	η² = 0.139
Total Sleep Time (hours)	(1.16) 4.44	(1.47) 3.87	F_(1,21) = 2.29	p = 0.14	η^{2 =} 0.098
Sleep Efficiency (%)	(9.13) 82.94	(8.19) 83.72	F_(1,21) = 0.14	p = 0.71	η² = 0.007
*Night sleep after day shift*
Time in Bed (hours)	(1.26) 6.34	(1.31) 6.55	F_(1,13) = 0.204	p = 0.65	η² = 0.015
Total Sleep Time (hours)	(1.25) 5.44	(1.18) 5.42	F_(1,13) = 0.002	p = 0.96	η² = 0.0
Sleep Efficiency (%)	(6.20) 82.60	(6.88) 82.63	F_(1,13) = 0.001	p = 0.98	η² = 0.0
*Naps (other than main sleep period) during the roster*
Time in Bed (hours)	(0.71) 2.1	(0.74) 2.59	F_(1,9) = 5.7	p = 0.04	η² = 0.388
Total Sleep Time (hours)	(0.51) 1.6	(0.73) 2.08	F_(1,9) = 6.47	p = 0.03	η² = 0.418
Sleep Efficiency (%)	(7.41) 72.61	(9.47) 79.78	F_(1,9) = 7.57	p = 0.02	η² = 0.457