Table 4.
Siblings cognitive trajectory group profiles (n = 1059)*
| Profiles | Cognitive trajectory group | Overall trajectory group differenceϮ | Pair‐wise comparison** | |||
|---|---|---|---|---|---|---|
| 1. High (n = 254) | 2. Normal (n = 413) | 3. Mild (n = 260) | 4. Moderate (n = 132) | |||
| Age | 28.6 (7.7) | 27.9 (8.0) | 27.8 (8.9) | 26.3 (8.9) | F = 5.6, P = 0.001 | 2 < 1 |
| Gender, % male | 55.5 | 43.6 | 41.5 | 40.2 | χ² = 14.1, P = 0.003 | 2 < 1; 2 > 4 |
| Education (Verhage)a | 6.1 (1.8) | 5.3 (2.0) | 4.5 (2.0) | 3.5 (2.1) | F = 62.2, P < 0.001 | 2 < 1; 2 > 3,4 |
| Ethnicity, % Dutch | 87.4 | 85.7 | 79.5 | 74.8 | χ² = 14.1, P = 0.003 | 2 < 1; 2 > 3,4 |
| IQ, Estimatedb | 120.7 (9.9) | 104.9 (9.5) | 92.1 (7.9) | 81.9 (6.7) | F = 684.7, P < 0.001 | 2 < 1; 2 > 3,4 |
| PAS, overall scorec | 0.9 (0.6) | 1.1 (0.7) | 1.2 (0.6) | 1.3 (0.7) | F = 13.6, P < 0.001 | 2 < 4, 2 > 1 |
| SIS‐Rd | ||||||
| Positive | 0.3 (0.4) | 0.4 (0.4) | 0.4 (0.4) | 0.5 (0.5) | F = 4.2, P = 0.006 | 2 < 4 |
| Negative | 0.3 (0.3) | 0.3 (0.2) | 0.3 (0.3) | 0.3 (0.3) | F = 2.5, P = 0.108 | |
| CAPE (Positive dimension)e | ||||||
| PE Frequency | 0.2 (0.2) | 0.2 (0.2) | 0.2 (0.2) | 0.3 (0.3) | F = 4.3, P = 0.006 | 2 < 4 |
| PE Distress | 0.4 (0.4) | 0.5 (0.5) | 0.5 (0.5) | 0.6 (0.5) | F = 2.4, P = 0.074 | |
| Cognitive performance | ||||||
| CPT performancef | 254.9 (58.9) | 245.3 (49.8) | 242.4 (59.7) | 220.9 (68.3) | F = 9.3, P < 0.001 | 2 > 4 |
| CPT variance (ms)g | 70.9 (26.0) | 74.6 (26.7) | 80.0 (30.3) | 80.2 (32.3) | F = 4.8, P = 0.003 | 2 > 1; 2 < 3,4 |
| Block designh | 56.3 (8.4) | 48.2 (12.4) | 37.1 (13.8) | 28.1 (11.9) | F = 208.3, P < 0.001 | 2 < 1;2 > 3,4 |
| Digit symboli | 89.7 (11.9) | 81.4 (13.0) | 72.7 (14.4) | 65.5 (13.8) | F = 121.7, P < 0.001 | 2 < 1;2 > 3,4 |
| Arithmeticj | 17.7 (2.6) | 14.9 (3.2) | 11.5 (3.6) | 8.2 (3.1) | F = 318.5, P < 0.001 | 2 < 1; 2 > 3,4 |
| Informationk | 21.8 (3.5) | 17.5 (4.0) | 14.1 (3.8) | 10.6 (3.6) | F = 299.9, P < 0.001 | 2 < 1; 2 > 3,4 |
| Immediate recalll | 31.4 (4.4) | 27.3 (4.9) | 25.0 (5.0) | 20.7 (4.8) | F = 159.0, P < 0.001 | 2 < 1; 2 > 3,4 |
| Delayed recallm | 11.3 (2.1) | 9.5 (2.4) | 8.5 (2.3) | 6.6 (1.8) | F = 113.2, P < 0.001 | 2 < 1; 2 > 3,4 |
*Table presents mean (standard deviation) or %; **Only significantly different trajectory groups are reported based on Dunnett's adjustment. The reference group is normal trajectory group; aEducation (Verhage): range 0 (no education), 3–5 (school diploma) to 8 (university degree); bIQ: Wechsler Adult Intelligence Scale‐III (WAIS‐III), short form; cPAS: Premorbid Adjustment Scale; dSIS‐R: Structured Inventory for Schizotypy—Revised (higher scores in PAS and SIS‐R reflect poorer outcomes); eCAPE: Community Assessment for Psychic Experiences; PE frequency and distress: Frequency of positive psychotic experiences and amount of distress of these PE; fCPT performance: Continuous performance test HQ, performance index, gCPT variance (ms): CPT‐HQ variance in reaction time (ms); hBlock design: WAIS‐III Block design; iDigit symbol: WAIS‐III Digit symbol substitution test; jArithmetic: WAIS‐III Arithmetic; kInformation: WAIS‐III Information; lImmediate recall: Word Learning Task (WLT) immediate recall; mDelayed recall: WLT Delayed recall; Cognitive trajectory: high performance (1) to moderately altered (4); Ϯ P < 0.05/20 was considered as statistically significant.