Table 1.
Diffusion MR imaging parameters for each site included. All contributed scans are part of larger cohorts described below and referenced. N-gradients refers to the number of diffusion weighted images obtained, and N-b0 refers to the number of images obtained with no diffusion sensitization (T2-weighted).
| QTIM | GOBS | BFS | LBC1936 | UMCU | |
|---|---|---|---|---|---|
| Relatedness | Twins | Pedigree | Unrelated | Unrelated | Unrelated |
| Race/ethnicity | Caucasian | Mexican–American | Caucasian | Caucasian | Caucasian |
| #Subjects contributed | 292 | 859 | 100 | 100 | 100 |
| Sex | 106M/186F | 351M/508F | 50M/50F | 50M/50F | 50M/50F |
| Age range (years) | 21–29 | 19–85 | 18–26 | 71–74 | 18–45 |
| Healthy | Yes | Yes | Yes | Yes | No |
| Scanner | Bruker | Siemens | GE | GE | Achieva |
| N-acquisitions | 1 | 1 | 1 | 1 | 2 |
| Field strength | 4 T | 3 T | 1.5 T | 1.5 T | 1.5 T |
| Voxel size (mm) | 1.8 × 1.8 × 2 | 1.7 × 1.7 × 3.0 | 2.5 × 2.5 × 2.5 | 2.5 × 2.5 × 2.5 | 2.5 × 2.5 × 2.5 |
| N-gradients | 94 | 55 | 64 | 64 | 32 |
| N-b0 | 11 | 3 | 7 | 7 | 8 |
| b-Value (s/mm2) | 1159 | 700 | 1000 | 1000 | 1000 |
| Reference | de Zubicaray et al. (2008) | Kochunov et al. (2011b) | Sprooten et al. (2011a) | Wardlaw et al. (2011) | Mandl et al. (2010) |