Table 4.
Group-dependent performance in neuropsychological tests*
| Group,† mean ± SD | Between-group differences ANCOVA | Correlation with Y-BOCS total score | Correlation with OFC activation | ||||||
|---|---|---|---|---|---|---|---|---|---|
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| Baseline | Group I, n = 21 | Group II, n = 19 | F value | p value | Effect size, Cohen d | ρ value | p value | ρ value | p value |
| Processing speed | |||||||||
| TMT-A | 37.0 ± 13.6 | 29.8 ± 8.8 | 12.573 | < 0.001 | 0.63 | 0.38 | 0.016 | 0.17 | 0.30 |
| Executive function and working memory | |||||||||
| WCST | |||||||||
| Categories completed | 5.8 ± 1.4 | 6.4 ± 0.8 | 1.727 | 0.30 | 0.53 | 0.00 | > 0.99 | 0.05 | 0.77 |
| Perseveration errors, % | 27.8 ± 16.8 | 16.5 ± 18.1 | 2.531 | 0.09 | 0.65 | 0.43 | 0.008 | 0.14 | 0.42 |
| Stroop | |||||||||
| Interference | 95.8 ± 27.8 | 91.4 ± 23.2 | 2.472 | 0.10 | 0.17 | 0.39 | 0.023 | 0.01 | 0.94 |
| Go/no-go | 1.7 ± 1.8 | 0.1 ± 0.3 | 8.626 | 0.001 | 1.24 | 0.46 | 0.003 | 0.47 | 0.002 |
| Set shift | 3.8 ± 6.4 | 1.1 ± 2.0 | 1.487 | 0.28 | 0.57 | 0.41 | 0.015 | 0.53 | 0.001 |
| TMT-B | 92.3 ± 46.0 | 63.5 ± 14.4 | 6.689 | 0.003 | 0.84 | 0.42 | 0.008 | 0.32 | 0.049 |
| N-back | 3.4 ± 4.3 | 2.8 ± 2.8 | 1.071 | 0.35 | 0.16 | 0.16 | 0.33 | 0.14 | 0.42 |
| Verbal learning and memory | |||||||||
| AVLT | |||||||||
| Immediate recall | 45.2 ± 10.1 | 54.2 ± 11.7 | 5.140 | 0.012 | 0.82 | −0.27 | 0.12 | −0.01 | 0.95 |
| Interference | 1.1 ± 3.0 | 1.4 ± 1.7 | 0.482 | 0.65 | 0.12 | 0.08 | 0.65 | −0.14 | 0.43 |
| Delayed recall | 1.5 ± 2.4 | 1.8 ± 2.2 | 0.783 | 0.47 | 0.13 | 0.03 | 0.86 | 0.12 | 0.51 |
| Visual memory and perception | |||||||||
| Rey figure test | |||||||||
| Reproduction | 39.1 ± 14.6 | 47.5 ± 12.4 | 8.939 | 0.001 | 0.62 | −0.54 | 0.001 | 0.02 | 0.93 |
| Memory | 117.0 ± 38.6 | 134.2 ± 34.2 | 12.208 | < 0.001 | 0.47 | −0.59 | < 0.001 | 0.01 | 0.95 |
| WAIS — block design | 30.9 ± 14.6 | 36.4 ± 9.3 | 4.282 | 0.023 | 0.45 | −0.32 | 0.06 | −0.13 | 0.46 |
| Attention | |||||||||
| d2 | 155.4 ± 49.3 | 136.8 ± 33.5 | 3.168 | 0.06 | 0.44 | −0.08 | 0.63 | 0.07 | 0.68 |
| CPT | 11.1 ± 10.2 | 10.1 ± 6.6 | 0.244 | 0.78 | 0.12 | −0.08 | 0.64 | −0.12 | 0.53 |
ANCOVA = analysis of covariance; AVLT = Rey Auditory-Verbal Learning Test; CPT = Continuous Performance Test; d2 = d2 Test of Attention; HZI = Hamburger Zwangsinventar; OCS = obsessive–compulsive symptoms; OFC = orbitofrontal cortex; SD = standard deviation; TMT = Trail Making Test; WAIS = Wechsler Adult Intelligence Scale; WCST = Wisconsin Card Sorting Test; Y-BOCS = Yale–Brown Obsessive–Compulsive Scale.
Neurocognitive characterization of study samples. The table provides group-specific means and standard deviations, the between-group comparison using ANCOVAs (covariate duration of illness), and the analysis of nonparametric correlations with the Y-BOCS total scores and with levels of task-specific activation in the OFC.
Group I = clozapine/olanzapine; group II = amisulpride/aripiprazole.