Table 2.

Neurocognitive parameters (mean±SD) and differences in performance of tests between study groups

P	Group 1 (PSQI ≥5)	Group 2 (PSQI <5)	t/U
d’ value	1.51±0.42	3.86±0.74	-7.08=0.001b
WCST correct (n)	14.85±3.55	33.75±6.38	-14.7=0.01a
WCST errors (n)	27.94±4.72	10.7±5.57	13.66=0.01a
WCST pers (n)	5.26±2.13	4.25±3.13	1.4=0.07a

*^aP-value based on a (two-tailed) Student’s t-test. ^bP-value based on a (two-tailed) Mann–Whitney U test. PSQI, Pittsburgh Sleep Quality Index; WCST, Wisconsin Card Sorting Test