Table 1.
Correlation matrix and means of study variables.
| 1. | 2. | 3. | 4. | 5. | 6. | 7. | 8. | 9. | 10. | 11. | 12. | 13. | 14 | M (SD) or % (N) |
|
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1. Age | - | 31.86 (2.48) | |||||||||||||
| 2. Sex | −0.01 | - | 64% (N= 1919) | ||||||||||||
| 3. Age of first drink | 0.04 | 0.16 | - | 15.70 (2.22) | |||||||||||
| 4. Age of regular drinking | 0.05 | 0.10 | 0.52 | - | 18.21 (2.68) | ||||||||||
| 5. AUD symptoms | −0.02 | −0.27 | −0.25 | −0.24 | - | 1.76 (2.02) | |||||||||
| 6. Household Income | 0.03 | −0.07 | −0.03 | −0.05 | −0.08 | - | 8.73 (2.02) | ||||||||
| 7. Educational Attainment | 0.02 | 0.08 | 0.02 | 0.01 | −0.16 | 0.25 | - | 3.32 (1.23) | |||||||
| 8. Neuroticism | −0.06 | 0.12 | 0.02 | 0.02 | 0.22 | −0.22 | −0.10 | - | 2.60 (0.73) | ||||||
| 9. Extraversion | 0.01 | 0.02 | −0.05 | −0.06 | −0.07 | 0.21 | 0.13 | −0.53 | - | 3.54 (0.55) | |||||
| 10. Agreeableness | 0.05 | 0.24 | 0.09 | 0.08 | −0.28 | 0.03 | 0.12 | −0.34 | 0.28 | - | 3.75 (0.47) | ||||
| 11. Openness | −0.04 | 0.04 | −0.09 | −0.06 | 0.03 | 0.01 | 0.26 | 0.06 | 0.13 | 0.07 | - | 3.31 (0.47) | |||
| 12. Conscientiousness | 0.08 | 0.13 | 0.08 | 0.04 | −0.22 | 0.16 | 0.16 | −0.42 | 0.31 | 0.26 | −0.05 | - | 3.84 (0.54) | ||
| 13. Early regular smoking | −0.01 | −0.05 | −0.20 | −0.18 | 0.24 | −0.12 | −0.28 | 0.11 | −0.08 | −0.13 | −0.02 | −0.12 | - | 7% (N = 208) | |
| 14. Early marijuana use | −0.08 | −0.12 | −0.35 | −0.32 | 0.27 | −0.03 | −0.14 | 0.06 | −0.06 | −0.14 | 0.11 | −0.14 | 0.40 | - | 15% (N = 459) |
| 15. CD symptoms | −0.03 | −0.22 | −0.30 | −0.21 | 0.42 | −0.10 | −0.25 | 0.11 | −0.08 | −0.28 | 0.03 | −0.18 | 0.35 | 0.32 | 0.88 (1.35) |
Note: Correlations presented are Pearson correlations (phi coefficients for dichotomous variables—sex, early regular smoking, and early marijuana use). Sample sizes for calculating correlations ranged from 2793 – 3005 twins, depending on data missingness. AUD = alcohol use disorder, CD = conduct disorder, M = mean, SD = standard deviation. For the variable of sex, females were coded ‘1’, while males were coded ‘0’. Bold indicates significance (p < 0.05).