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Comparison of monozygotic (MZ) and dizygotic (DZ) cross-twin cross-trait peer group deviance and cannabis use polychoric correlations with 95% confidence intervals for each time period at 15 to 17 years, 18 to 21 years and 22 to 25 years.
| 15–17 years | 18–21 years | 22–25 years | |
|---|---|---|---|
| MZ | 0.52 (0.45 0.59) | 0.48 (0.41 0.55) | 0.44 (0.36 0.51) |
| DZ | 0.38 (0.27 0.47) | 0.36 (0.25 0.45) | 0.29 (0.18 0.39) |
