Table 2.

VEP values in COPD group and healthy volunteers group

VEP parameters	Eye tested	Healthy volunteers group (n = 40) Mean±SD	COPD group (n = 40) Mean±SD	Significance of difference between two groups (P value)
Latency P100 (ms)	Right	95.26±3.42	105.87±7.92	<0.001*
	Left	96.25±3.33	105.60±8.86	<0.001*
Amplitude P100 (μV)	Right	4.85±1.3	2.53±1.12	<0.001*
	Left	4.72±1.37	2.62±1.12	<0.001*

COPD = Chronic obstructive pulmonary disease; SD = Standard deviation; VEP = Visual evoked potentials;

^*The difference between the 2 groups was statistically significant