Table 4.

Mean values and standard deviations (SD) of N200 and P300 parameters in HT patients depending on the duration of the disease.

Duration of the disease	N/A	< 10 years		11–20 years		21–30 years		> 30 years
No of patients	CG (n = 45)	HT (n = 19)	HT vs CG	HT (n = 20)	HT vs CG	HT (n = 16)	HT vs CG	HT (n = 13)	HT vs CG
	Mean (SD)	Mean (SD)	p-value	Mean (SD)	p-value	Mean (SD)	p-value	Mean (SD)	p-value
Latency (ms)
N200 Fz	211.5 (20.2)	232.4 (27.9)	0.001	234.2 (30.1)	< 0.001	256.9 (34.3)	< 0.001	273.4 (33.8)	< 0.001
Cz	211.3 (20.6)	232.3 (28.9)	0.001	234.5 (29.1)	< 0.001	255.9 (33.4)	< 0.001	270.4 (32.8)	< 0.001
Pz	212.1 (19.7)	235.2 (25.4)	0.002	233.4 (28.9)	0.001	256.5 (36.4)	< 0.001	268.0 (31.0)	< 0.001
P300 Fz	322.8 (21.2)	336.3 (21.5)	0.02	347.7 (16.7)	< 0.001	358.9 (19.7)	< 0.001	370.8 (18.5)	< 0.001
Cz	323.5 (22.3)	336.4 (21.7)	0.04	347.6 (14.2)	< 0.001	359.3 (20.0)	< 0.001	373.3 (19.3)	< 0.001
Pz	325.6 (22.9)	340.6 (20.2)	0.01	348.0 (14.1)	< 0.001	359.1 (20.6)	< 0.001	373.4 (24.0)	< 0.001
Amplitude (uV)
N200 Fz	4.00 (2.44)	4.66 (3.88)	0.41	3.58 (2.65)	0.54	2.93 (1.72)	0.11	2.46 (1.93)	0.14
Cz	3.44 (2.53)	4.04 (2.92)	0.42	3.39 (2.19)	0.94	3.02 (1.79)	0.54	2.92 (1.52)	0.48
Pz	3.06 (1.89)	3.22 (2.39)	0.77	3.03 (2.49)	0.96	2.88 (2.16)	0.75	2.73 (1.49)	0.57
P300 Fz	8.04 (3.93)	6.04 (3.19)	0.05	5.89 (4.58)	0.05	5.55 (3.88)	0.03	5.50 (2.82)	0.03
Cz	8.02 (3.73)	5.69 (2.66)	0.01	5.94 (4.79)	0.05	5.71 (4.39)	0.05	5.02 (2.41)	< 0.001
Pz	7.86 (3.81)	4.95 (2.54)	0.01	5.02 (4.26)	0.001	6.16 (4.48)	0.01	3.86 (2.21)	< 0.001

CG control group, HT Hashimoto’s thyroiditis, SD standard deviation, Fz frontal region, Cz central region, Pz parietal region.