Table 1.
Sample Characteristics
| Statistics | |||||||
|---|---|---|---|---|---|---|---|
| Healthy Individuals | Psychosis | t/x2 | df | P | |||
| Sample size | 70 | 124 | |||||
| Gender (M/F) | 44/26 | 85/39 | 0.65 | 1 | .420 | ||
| Race (W/AA/O) | 51/14/5 | 91/28/5 | 0.98 | 2 | .613 | ||
| Age, mean (SD) | 28.2 | 9.0 | 27.3 | 8.6 | 0.66 | 192 | .508 |
| Education, mean (SD) | 16.0 | 1.9 | 13.9 | 2.1 | 7.06 | 192 | <.001 |
| Parental education, mean (SD) | 14.9 | 2.3 | 15.0 | 2.6 | 0.21 | 191 | .837 |
| Premorbid IQ, mean (SD) | 108.0 | 14.6 | 104.0 | 9.8 | 2.29 | 192 | .023 |
| Neuropsychological functioning, mean (SD) | |||||||
| AX-CPT d-prime | 3.5 | 0.7 | 2.7 | 1.1 | 5.61 | 192 | <.001 |
| WCST total errors standard score | 107.4 | 12.5 | 95.8 | 13.9 | 5.43 | 165 | <.001 |
| WMS-III Working Memory Index | 106.6 | 12.6 | 97.5 | 13.2 | 4.69 | 191 | <.001 |
| SCIP Composite Z-score | 0.28 | 0.59 | −0.69 | 0.84 | 8.46 | 192 | <.001 |
| Clinical characteristics | |||||||
| Psychotic disorder (BP/SCZ) | 49/75 | — | — | — | |||
| Early stage/chronic | 62/62 | — | — | — | |||
| APD (yes/no) | 95/29 | — | — | — | |||
| Mood stabilizer (yes/no) | 51/73 | — | — | — | |||
| Age at illness onset, mean (SD) | 22.0 | 5.9 | — | — | — | ||
| Duration of illness (years), mean (SD) | 5.8 | 7.4 | — | — | — | ||
| PANSS positive, mean (SD) | 15.3 | 9.0 | — | — | — | ||
| PANSS negative, mean (SD) | 12.5 | 5.0 | — | — | — | ||
| PANSS general, mean (SD) | 27.9 | 7.9 | — | — | — | ||
| Depression (HAMD), mean (SD) | 10.0 | 9.2 | — | — | — | ||
| Mania (YMRS), mean (SD) | 6.8 | 12.2 | — | — | — | ||
| APD dose (CPZ equiv), mean (SD) | 336.2 | 217.7 | — | — | — | ||
Abbreviations: AA = African American; APD = Antipsychotic Drug; BP = Psychotic Bipolar Disorder; C = Caucasian; CPT = Continuous Performance Test; CPZ = Chlorpromazine; F = female; HAMD = Hamilton Depression Scale; HI = Healthy Individuals; M = male; O = Other; PANSS = Positive and Negative Syndrome Scale; SCIP = Screen for Cognitive Impairment in Psychiatry; SCZ = Schizophrenia; WCST = Wisconsin Card Sorting Test; WMS = Wechsler Memory Scale; YMRS = Young Mania Rating Scale.