Table 2. ATC’s sleep parameters assessed by MCTQ^shift analysis (N=133)

MCTQ scale	Workdays on day shifta			Free days after day shiftb*			Workdays on night shiftc			Free days after night shiftd			χ2 / Z (p)
	M	MED	Std.	M	MED	Std.	M	MED	Std.	M	MED	Std.
SPrep, 24h clock (h)	8.48	1.00	10.66	6.96	2.00	8.78	10.30	10.00	8.38	10.17	10.00	8.99	23.385(<.001)b<c,d†
SLat (h)	0.36	0.33	0.26	0.35	0.33	0.23	0.33	0.25	0.30	0.29	0.17	0.22	29.956(<.001)d<a,b†
SO, 24h clock (h)	6.13	1.25	9.36	5.86	2.00	7.81	8.28	9.33	7.62	9.02	9.42	8.58	27.243(<.001)b<a<d†
SE, 24h clock (h)	6.88	6.83	1.74	9.46	9.00	3.12	9.77	9.00	3.99	9.46	9.00	3.66	82.489(<.001)a<b,c,d†
GU, 24h clock (h)	6.89	6.85	1.74	9.46	9.02	3.12	9.78	9.00	3.98	9.47	9.00	3.66	73.837(<.001)a<b,c,d†
SD (h)	6.16	6.00	1.31	6.66	7.05	2.56	5.28	5.33	2.70	6.22	6.50	2.65	24.447(<.001)c<a,b,d†
NapD (h)	0.20	0.00	0.43	0.41	0.00	0.85	0.57	0.00	1.22	0.34	0.00	0.81	1.191(.755)
SD24 (h)	6.37	6.17	1.33	7.07	7.33	2.61	5.85	5.58	3.20	6.56	6.92	2.82	13.327(.004)a<b†
MS, 24h clock (h)	3.98	3.75	2.35	6.13	5.25	3.49	7.53	5.58	4.45	6.89	5.00	4.31	69.984(<.001)a<b<c,a<d†
SJL (h)	M±SD = 2.73±3.54Median = 1.55						M±SD = 2.71±3.56Median = 0.75						5.365(.221)

Note. M=mean, MED=median, Std=standard deviation; ATC=air traffic controllers; Sprep=preparing to fall asleep; SLat=sleep latency; SO=sleep onset; SE=sleep end; GU=getting out of bed; SD=sleep duration; NapD=nap duration; SD24=24h total sleep duration; MS=mid-sleep; SJL=social jetlag.
After day shifts and before night shifts.
Wilcoxon Signed-Rank test with Bonferroni correction.