Table 3. Correlation between the “sleep quality” and “age” variables, as well as “P300 wave amplitude and latency”.

		Age	Schooling	Latency			Range
				Cz	Fz	Pz	Cz	Fz	Pz
Sleep quality	Correlation	-0.02	0.30	-0.08	-0.07	-0.32	-0.29	-0.46	-0.30
	p-value	0.88	0.117	0.69	0.73	0.12	0.15	0.02*	0.15
	N	28	28	25	24	24	25	24	24