Table 2

Demographic and clinical characteristics and ratings scores of study participants

Group; mean ± SD*
VariableControl, n = 45Psychosis, n = 42Statisticp value
Male, % (male/female)44.4% (20/25)71.4% (30/12)χ21 = 6.470.011
Right handed, % (r/l/a)80.0% (36/9/0)88.1% (37/4/1)χ22 = 2.840.24
Age, yr24.8 ± 3.422.7 ± 3.9t85 = −2.570.012
Predicted IQ103.9 ± 7.8103.5 ± 7.4t48 = −0.220.83
Years of education14.5 ± 1.812.5 ± 1.8t84 = −5.29< 0.001
Intracranial volume, cm31530 ± 1351569 ± 174t77.1 = 1.140.26
HAM-D2.9 ± 2.514.8 ± 7.1t27.3 = 7.93< 0.001
K1015.7 ± 4.524.5 ± 8.6t48.7 = 5.45< 0.001
DASS Depression scale4.9 ± 7.116.3 ± 11.5t60.5 = 5.31< 0.001
DASS Anxiety scale3.9 ± 5.714.2 ± 10.6t53.3 = 5.32< 0.001
DASS Stress scale7.8 ± 7.716.4 ± 9.1t79 = 4.57< 0.001
BPRS Total43.8 ± 11.8
BPRS Positive Symptoms12.9 ± 5.4
BPRS Negative Symptoms8.7 ± 4.2
RVP-A0.16 ± 1.05−0.55 ± 1.11t63 = −2.640.011
RVP-B−0.22 ± 1.11−0.19 ± 0.9t63 = 0.150.88
RAVLT Sum0.00 ± 0.83−0.77 ± 1.09t64 = −3.210.002
RAVLT A70.08 ± 0.95−0.92 ± 1.35t59.4 = −3.46< 0.001
COWAT Letters−0.17 ± 0.86−0.26 ± 0.94t63 = −0.370.71
COWAT Animals0.56 ± 0.88−0.10 ± 0.84t63 = −3.090.003
SSP0.68 ± 1.01−0.18 ± 1.08t62 = −2.970.004
TMT-A0.66 ± 0.660.17 ± 1.03t64 = −2.280.026
TMT-B0.39 ± 1.13−0.28 ± 1.34t63 = −2.140.036
  • BPRS = Brief Psychiatric Ratings Scale; COWAT = Controlled Word Association Test; DASS = Depression Anxiety and Stress Scales; HAM-D = Hamilton Rating Scale for Depression; K10 = Kessler-10; RAVLT = Rey Auditory Verbal Learning Test; RVP = Rapid Visual Processing; SSP = spatial span; TMT = Trail-Making Test.

  • * Unless otherwise indicated.

  • Significant differences in sex and handedness were evaluated using a Pearson χ2 test. All other significance values were evaluated using independent samples t tests. Significance levels were set at p < 0.05 (2-tailed).