Summary of adjusted brain volumes and planned between-group comparisons
| Group; brain volume, mean ± SD, mm3 | Comparison; pairwise test effect size (95% CI) | ||||||
|---|---|---|---|---|---|---|---|
| Region | All schizophrenia (n = 70) | MZ Dc unaffected (n = 16) | DZ Dc unaffected (n = 6) | All controls (n = 76) | All schizophrenia v. all controls | MZ Dc unaffected v. all controls | DZ Dc unaffected v. all controls |
| Whole brain | 1134.2 ± 129.6 | 1144.4 ± 188.6 | 1145.5 ± 152.8 | 1181.1 ± 109.6 | −56.9 (−104.0 to −9.7) t = −3.86 p < 0.001 | −54.3 (−130.3 to 21.6) t = −1.42 p = 0.16 | 35.7 (−48.9 to 120.4) t = 0.84 p = 0.40 |
| Grey matter | 675.3 ± 76.8 | 688.7 ± 106.2 | 690.6 ± 74.3 | 706.2 ± 69.2 | −45.9 (−67.7 to −24.0) t = −4.17 p < 0.001 | −19.5 (−56.5 to 17.5) t = −1.05 p = 0.30 | −0.05 (−36.3 to 36.2) t = 0.00 p = 0.99 |
| White matter | 465.0 ± 65.9 | 448.5 ± 80.0 | 514.2 ± 91.3 | 478.7 ± 55.5 | −27.2 (−49.2 to −5.2) t = −2.45 p = 0.016 | −31.6 (−66.9 to 3.7) t = −1.78 p = 0.08 | 36.6 (−18.8 to 92.1) t = 1.31 p = 0.19 |
| Right hippocampus | 1.85 ± 0.39 | 1.92 ± 0.26 | 1.76 ± 0.28 | 2.02 ± 0.27 | −138.7 (−272.3 to −5.0) t = −2.06 p = 0.040 | −92.3 (−231.8 to 47.2) t = −1.32 p = 0.19 | −301.7 (−459.6 to −143.9) t = −3.80 p < 0.001 |
| Left hippocampus | 1.94 ± 0.42 | 1.94 ± 0.32 | 1.74 ± 0.31 | 2.02 ± 0.27 | −28.8 (−168.3 to 110.7) t = 0.41 p = 0.68 | −47.0 (−197.1 to 103.1) t = −0.62 p = 0.54 | −348.3 (−545.4 to −151.2) t = −3.51 p = 0.001 |
CI = confidence interval; Dc = discordant; DZ = dizygotic; MZ = monozygotic; SD = standard deviation.