Table 5. Results of the ROC analysis using the exploratory dataset.

	Area under curve	Cut-off value	True positives	False negatives	True negatives	False positives	Sensitivity	Specificity	P
Professional vs rest	0.693	0.0226	10	4	59	40	71.4	59.6	0.0097
Amateur vs rest	0.725	-0.0117	32	13	50	18	71.1	73.5	<0.0001
Professional vs amateur	0.800	-0.0118	12	2	32	13	85.7	71.1	<0.0001
Professional vs academy	0.603	n.s.	n.s.	n.s.	n.s.	n.s.	n.s.	n.s.	n.s.
Amateur vs academy	0.706	-0.0044	33	12	37	17	73.3	68.5	<0.0001

n.s.–not significant