Table 1.
Participant demographics and clinical characteristics.
| SZ | BD-I | HC | Statistics | P -value | ||||
|---|---|---|---|---|---|---|---|---|
| N | % | N | % | N | % | |||
| Female, n (%) | 11 | 55.0% | 12 | 57.1% | 10 | 55.6% | Χ2 = 0.02 | 0.990 |
| Medication class, n (%) | ||||||||
| Antipsychotics | 19 | 95.0% | 9 | 42.9% | Χ2 = 12.9 | 0.000 | ||
| Mood stabilisers | 4 | 20.0% | 12 | 57.1% | Χ2 = 5.9 | 0.015 | ||
| Antidepressants | 6 | 30.0% | 8 | 38.1% | Χ2 = 0.3 | 0.585 | ||
| Mean | SD | Mean | SD | Mean | SD | Statistics | P -value | |
| Age, years | 33.6 | 8.7 | 36.9 | 10.2 | 36.6 | 10.7 | F(df = 2,56) = 0.70 | 0.505 |
| Education, years | 13.7 | 2.7 | 13.3 | 2.7 | 14.4 | 1.6 | F(df = 2,56) = 1.1 | 0.347 |
| Premorbid IQa | 103.3 | 9.3 | 105.4 | 7.9 | 106.3 | 9.9 | F(df = 2,53) = 0.5 | 0.599 |
| Handedness | 93.0 | 11.7 | 77.1 | 40.6 | 87.2 | 17.4 | F(df = 2,56) = 1.8 | 0.172 |
| Duration of illness | 9.2 | 4.8 | 10.4 | 7.3 | t(df = 39) = 0.6 | 0.529 | ||
| Antipsychotic dosage | 498.1 | 446.1 | 126.2 | 183.7 | ||||
| Antidepressant dosage | 28.5 | 54.6 | 40.8 | 77.0 | ||||
| GAF scores | 49.6 | 16.3 | 52.8 | 16.2 | t(df = 39) = 0.6 | 0.536 | ||
| HAMD | 10.3 | 7.3 | 0.000b | |||||
| YMRS | 2.5 | 2.6 | 0.568b | |||||
| PANSS scores | ||||||||
| Total | 15.4 | 5.1 | 9.0 | 4.2 | t(df = 39) = 4.3 | 0.000 | ||
| Positive | 18.6 | 4.1 | 9.4 | 3.3 | t(df = 39) = 7.8 | 0.000 | ||
| Negative | 36.8 | 7.6 | 29.4 | 8.5 | t(df = 39) = 2.9 | 0.006 | ||
| General | 70.8 | 15.2 | 47.8 | 14.1 | t(df = 39) = 5.0 | 0.000 | ||
| Task performance | ||||||||
| Stop-signal delay | 400.3 | 152.2 | 433.4 | 148.7 | 437.4 | 147.4 | F(df = 2,56) = 0.36 | 0.70 |
| Stop-signal reaction time | 366.7 | 53.7 | 335.8 | 83.0 | 302.5 | 54.0 | F(df = 2,56) = 4.5 | 0.015c |
| Percentage of miss trials | 2.7 | 4.0 | 3.7 | 9.6 | 0.9 | 1.5 | F(df = 2,56) = 0.99 | 0.38 |
SZ, schizophrenia; BD-I, bipolar I disorder; GAF, Global Assessment of Functioning scale; HC, healthy control; PANSS; Positive and Negative Syndrome Scale.
aData were missing for two patients with SZ and one with BD-I.
bAnalysed using Mann–Whitney U test.
cPatients with SZ demonstrated longer SSRTs than HCs (P = 0.011); no significant differences were observed between patients with BD-I and HCs (P = 0.26) or between the SZ and BD-I groups (P = 0.30).