Demographic and clinical characteristics of the participants*
| Group; mean ± SD† | Patient subgroup; mean ± SD† | ||||||
|---|---|---|---|---|---|---|---|
| Characteristic | Controls n = 30 | Schizophrenia n = 39 | p value | Antipsychotic-free, n = 13 | Clozapine n = 10 | Haloperidol n = 16 | p value |
| Age, yr; mean (range) | 24.57 (18–31) | 23.87 (18–35) | 0.47 | 25.5 (20–35) | 22.2 (18–32) | 22.63 (18–32) | 0.21 |
| Education, yr | 11.8 ± 0.41 | 10.46 ± 0.85 | < 0.001 | 10.5 ± 0.88 | 10.8 ± 0.92 | 10.19 ± 0.75 | 0.19 |
| PANSS | |||||||
| Positive | 14.2 ± 5.6 | — | 17.3* ± 4.6 | 12.5 ± 7.1 | 12.8 ± 4.5 | 0.047 | |
| Negative | 18.3 ± 6.1 | — | 17.9 ± 4.8 | 17.8 ± 7.1 | 19.0 ± 6.7 | 0.86 | |
| General | 31.0 ± 6.9 | — | 33.8 ± 8.0 | 27.8 ± 7.0 | 30.7 ± 5.0 | 0.11 | |
| Total | 63.5 ± 14.9 | — | 69.0 ± 14.9 | 58.1 ± 18.4 | 62.4 ± 11.5 | 0.21 | |
| Duration of illness, mo. | 21.8 ± 16.2 | 21.85 ± 18.8 | 30.6 ± 16.5 | 16.2 ± 11.4 | 0.08 | ||
| Range | 1–60 | — | 1–60 | 6–54 | 1–38 | — | |
| CPZ equivalents | 353 ± 132 | 223 ± 62 | 0.013 | ||||
| DDD | 0.88 ± 0.32 | 0.46 ± 0.12 | 0.002 | ||||
CPZ = chlorpromazine; DDD = defined daily dose; PANSS = Positive and Negative Symptoms Scale; SD = standard deviation.
↵* Differences between controls and patients with schizophrenia were assessed using the Student t test. Differences among patient subgroups were assessed using univariate analyses of variance.
↵† Unless otherwise indicated.