Table 1.
Characteristics of study population
| Entire sample (N=875) | |||
|---|---|---|---|
| Age, years | 28.8 ± 3.7 (22.0 – 37.0) | ||
| Sex (m/f)* | 386/489 | ||
| Race (white/non-white)* | 638/237 | ||
| Handedness | 65.3 ± 45.0 (−100 – 100) | ||
| BMI | 26.6 ± 5.3 (16.5 – 47.8) | ||
| Height, cm | 171.0 ± 10.0 (147.3 – 203.2) | ||
| Weight, kg | 78.2 ± 18.1 (42.2 – 138.3) | ||
| Education, years (n=874) | 14.9 ± 1.8 (11.0 – 17.0) | ||
| Fluid Intelligence (PMAT; n=869) | 16.6 ± 4.9 (4.0 – 24) | ||
|
| |||
| Twin pairs only | MZ (n=172) | DZ (n=164) | p |
|
| |||
| Age, years | 29.9±3.3 | 28.9±3.4 | 0.01 |
| Gender (m/f)* | 48/124 | 71/93 | 0.004✦ |
| Race (white/non-white)* | 141/31 | 128/36 | 0.41 |
| Handedness | 68.9±45.6 | 63.9±43.9 | 0.31 |
| BMI | 26.3±4.8 | 26.6±5.3 | 0.58 |
| Height, cm | 167.8±8.8 | 172.1±9.4 | <0.001 |
| Weight, kg | 74.1±15.6 | 79.1±19.0 | 0.01 |
| Education, years | 15.0±1.8 | 15.0±1.9 | 0.81 |
| Fluid Intelligence (PMAT) | 16.2±4.6 | 17.0±4.8 | 0.13 |
Characteristics are listed as mean ± SD with corresponding ranges, except for*. Two Sample t-Tests and ✦Fisher’s Exact Test were used for group-wise statistics. PMAT Penn Progressive Matrices number of correct responses.