a trend towards significancep < 0.01
The SWD group had significantly lower sleep efficiency than the non-SWD group, or showed a trend towards significance (on days off: 89 ± 5 and 94 ± 2%, Group: F 29.041 = 11.91, p < 0.01; before morning shifts: 87 ± 6 and 93 ± 4%, Group: F 27.304 = 11.84, p < 0.01; after evening shifts: 89 ± 4 and 94 ± 3%, Group: F 25.924 = 13.66, p < 0.01; and after night shifts: 90 ± 4 and 93 ± 3%, Group: F 22.373 = 3.73, p = 0.066, respectively).