Table 1.
Characteristics of the sample
| Whole sample (N = 1286) | HC (N = 454) | ROD (N = 267) | CHR (N = 270) | ROP (N = 295) | Statistic | p value | Post-hoc | |
|---|---|---|---|---|---|---|---|---|
| Age | CHR<HC, p = 0.003* CHR<ROD, p = 0.001* CHR<ROP, p < 0.001* |
|||||||
| Mean (s.d.) | 25.07 (5.88) | 25.17 (5.99) | 26.64 (6.13) | 23.67 (5.26) | 25.67 (5.84) | F = 6.939 | <0.001* | |
| Range | 15–41a | 15–41a | 15–40 | 15–40 | 15–40 | |||
| Gender | ROP>HC (Male), p < 0.001* ROP>CHR (Male), p = 0.032* | |||||||
| Male % | 47.5 | 40.6 | 49.2 | 46.1 | 57.8 | χ2 = 21.771 | <0.001* | |
| Estimated Current IQ | HC>CHR, p < 0.001* HC>ROD, p < 0.001* HC>ROP, p < 0.001* CHR>ROP, p < 0.001* ROD>ROP, p < 0.001* |
|||||||
| Mean (s.d.) | 105.58 (12.09) | 110.00 (10.03) | 105.54 (11.83) | 105.46 (10.99) | 98.92 (13.10) | F = 56.655 | <0.001* | |
| Education Years | HC>CHR, p < 0.001* HC>ROD, p < 0.001* HC>ROP, p < 0.001* ROD>CHR, p = 0.014* |
|||||||
| Mean (s.d.) | 14.60 (3.12) | 15.71 (3.09) | 14.35 (3.06) | 13.60 (2.55) | 14.00 (3.20) | F = 34.339 | <0.001* | |
| Ethnicity | ||||||||
| N (%) | χ2 = 43.591 | <0.001* | ROD>ROP (White), p = 0.004* | |||||
| White | 1067 (83.0) | 381 (83.9) | 235 (88.0) | 226 (83.7) | 225 (76.3) | HC>ROD (Asian), p = 0.001* | ||
| Asian | 72 (5.6) | 39 (8.6) | 4 (1.5) | 11 (4.1) | 18 (6.1) | ROP>ROD (Asian), p = 0.026* | ||
| Black | 26 (2.0) | 6 (1.3) | 3 (1.1) | 4 (1.5) | 13 (4.4) | ROP>HC (Black), p = 0.041* | ||
| Mixed race | 28 (2.2) | 14 (3.1) | 3 (1.1) | 4 (1.5) | 7 (2.4) | CHR>HC (Other), p = 0.045* | ||
| Other | 62 (4.8) | 10 (2.2) | 16 (6.0) | 16 (5.9) | 20 (6.8) | ROD>HC (Other), p = 0.045* | ||
| Unknown | 31 (2.4) | 4 (0.9) | 6 (2.2) | 9 (3.3) | 12 (4.1) | ROP>HC(Other), p = 0.008* |
N, Number of Participants; s.d., Standard Deviation; F, one-way ANOVA; χ2, Chi-squared; *, Statistically significant at a level of p⩽0.05.
a
Note: One participant in the HC group was assessed on the date of their 41st birthday and retained in analysis.