Table 4.

Mean, Std. deviation, KMO and Cronbach alpha obtained in two phases .

Phase 1. Pilot study (n=110)						Phase 2. Administration among AMT operators (n=121)
Questionnaire	Dimension	Mean	Desv Std.	KMO	Alpha	Questionnaire	Mean	Desv Std.	KMO	Alpha
NASA-TLX α: 0.791, KMO: 0.801	Mental demands	3.71	0.949	N/A	N/A	NASA-TLX α: 0.583, KMO: 0.664	3.61	0.86	N/A	N/A
	Physical demands	2.12	1.07	N/A	N/A		3.57	1.03	N/A	N/A
	Temporal demands	3.34	0.94	N/A	N/A		3.26	0.81	N/A	N/A
	Effort	3.75	0.85	N/A	N/A		3.88	0.77	N/A	N/A
	Performance	3.85	0.86	N/A	N/A		4.23	0.68	N/A	N/A
	Frustration	3.13	1.16	N/A	N/A		2.81	1.00	N/A	N/A
ISTAS α: 0.860, KMO: 0.712.	Psychological demands	16.9	3.48	0.728	0.733	ISTAS α: 0.702, KMO: 0.753.	15.33	3.69	0.711	0.654
	Active work	35	6.55	0.825	0.813		32.8	4.71	0.628	0.6
	Job insecurity	11.2	4.09	0.548	0.521		8.17	3.56	0.681	0.641
	Social suport	35.5	6.09	0.738	0.759		35.41	6.38	0.755	0.8
	Estimate to work	13.16	2.93	0.760	0.764		11.82	3.65	0.768	0.846
	Double presence	11.7	3.24	0.564	0.485		8.65	2.54	0.601	0.591
SOFI-S α: 0.845, KMO: 0.756.	Lack of energy	6.54	2.56	0.728	0.836	SOFI-S α: 0.881, KMO: 0.813.	7.76	2.29	0.700	0.827
	Physical exertion	6.59	2.73	0.513	0.433		6.61	2.00	0.552	0.558
	Physical discomfort	6.18	3	0.625	0.773		6.18	2.24	0.652	0.742
	Lack of motivation	6.28	2.31	0.731	0.887		1.99	0.72	0.619	0.754
	Sleepiness	8.74	2.85	0.664	0.794		5.677	2.24	0.708	0.793
FAS α: 0.505 KMO:0.746	Physical fatigue	14.30	3.11	0.596	0.427	FAS	N/A	N/A	N/A	N/A
	Mental fatigue	13.54	3.05	0.632	0.179		N/A	N/A	N/A	N/A
OFER α: 0.,724 KMO: 0.813.	Acute fatigue	10.35	3.76	0.779	0.786	OFER α: 0.678, KMO: 0.803	10.19	3.45	0.768	0.677
	Chronic fatigue	15.43	2.91	0.771	0.427		14.46	2.62	0.725	0.695
	Intershift recovery	12.9	2.52	0.561	0.700		13.13	2.15	0.689	0.751
α: 0.842; KMO: 0.75; 84 items.						Alfa: 0.806; KMO: 0.617; 74 items.
Time to complete the survey: 15-20 min.						Time to complete the survey: 20-15 min.