Table V.

Results of the neuropsychology test between the POCD and non-POCD groups (mean ± SD) at 1 month post-operation.

Items	Time	POCD (n=12)	Non-POCD (n=68)
Summation	Pre-operative	58±16	62±23
	Post-operative	37±31a,c	51±24a
Visual	Pre-operative	9.4±1.4	8.9±1.9
reproduction	Post-operative	7.2±2.4b	8.4±2.2
Associative	Pre-operative	12.1±1.8	11.4±3.5
learning	Post-operative	9.1±2.4b,c	11.6±3.4
Digit	Pre-operative	4.7±1.2	4.6±1.1
span-forward	Post-operative	4.6±1.3	4.7±1.3
Digit	Pre-operative	2.3±1.0	3.2±1.1
span-backward	Post-operative	1.8±1.4b,c	3.0±0.9
Digit	Pre-operative	21±9	20±7
symbol	Post-operative	21±7	20±7
Ligature	Pre-operative	58±11	56±13
	Post-operative	59±10c	55±12
Total z-score		3.7±1.1c	1.2±0.7

^aP<0.05

^bP<0.01, compared to the pre-operative time

^cP<0.01, compared to the non-POCD; POCD, postoperative cognitive dysfunction.