Table 3.
Demographic and substance use characteristics of Philadelphia Neurodevelopmental Cohort (PNC) participants 14 and older, separated by cannabis use
| Non-User n = 3,401 | Occasional Cannabis User n = 940 | Frequent Cannabis User n = 227 | Occasional vs. Non-User p | Frequent vs. Non-User p | Occasional vs. Frequent p | p | |
|---|---|---|---|---|---|---|---|
|
|
|
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| Age | 16.4 (1.9) | 17.4 (1.8) | 17.6 (1.7) | <0.001 | <0.001 | 0.134 | <0.001 |
| Sex M/F (%Male) | 1,419/1,982 (41.7%) | 437/503 (46.5%) | 156/71 (68.7%) | 0.009 | <0.001 | <0.001 | <0.001 |
| Race | --- | --- | --- | 0.434 | |||
| Caucasian | 1,889 (55.5%) | 549 (58.4%) | 119 (52.4%) | --- | --- | --- | |
| African-American | 1,147 (33.7%) | 300 (31.9%) | 82 (36.1%) | --- | --- | --- | |
| Asian/Native American/Other | 365 (10.7%) | 92 (9.7%) | 26 (11.5%) | --- | --- | --- | |
| WRAT-4 Word Reading | 101.7 (17.5) | 100.6 (15.8) | 98.5 (14.7) | 0.059 | 0.005 | 0.100 | 0.006 |
| Age at First Cannabis Use | --- | 14.6 (1.7) | 13.7 (1.6) | --- | --- | <0.001 | |
| Age at Daily Cannabis Use | --- | --- | 15.4 (1.8) | --- | --- | --- | |
| Cannabis Use During Past Year | --- | --- | --- | ||||
| No use in past year | 3,401 (100.0%) | 343 (36.5%) | 0 (0.0%) | --- | --- | --- | |
| < 1 time a month | 0 (0.0%) | 272 (28.9%) | 0 (0.0%) | --- | --- | --- | |
| Once a month | 0 (0.0%) | 94 (10.0%) | 0 (0.0%) | --- | --- | --- | |
| 2–3 times a month | 0 (0.0%) | 137 (14.6%) | 0 (0.0%) | --- | --- | --- | |
| 1–2 times a week | 0 (0.0%) | 94 (10.0%) | 0 (0.0%) | --- | --- | --- | |
| 3–4 times a week | 0 (0.0%) | 0 (0.0%) | 77 (33.9%) | --- | --- | --- | |
| Everyday or nearly everyday | 0 (0.0%) | 0 (0.0%) | 150 (66.1%) | --- | --- | --- | |
| Alcohol Use During Past Yeara | <0.001 | <0.001 | <0.001 | <0.001 | |||
| No use | 2,184 (78.9%) | 131 (16.3%) | 24 (11.3%) | --- | --- | --- | |
| < 1 time a month | 342 (12.4%) | 231 (28.7%) | 41 (19.4%) | --- | --- | --- | |
| Once a month | 95 (3.4%) | 120 (14.9%) | 32 (15.1%) | --- | --- | --- | |
| 2–3 times a month | 103 (3.7%) | 167 (20.7%) | 61 (28.8%) | --- | --- | --- | |
| 1–2 times a week | 40 (1.5%) | 116 (14.4%) | 42 (19.8%) | --- | --- | --- | |
| 3–4 times a week | 4 (0.1%) | 36 (4.5%) | 11 (5.2%) | --- | --- | --- | |
| Everyday or nearly everyday | 0 (0.0%) | 5 (0.6%) | 1 (0.5%) | --- | --- | --- | |
| Psychopathology Factors b | |||||||
| Overall Psychopathology | 0.07 (0.5) | 0.25 (0.5) | 0.42 (0.5) | <0.001 | <0.001 | <0.001 | <0.001 |
| Mood-Anxiety | 0.01 (0.4) | 0.04 (0.4) | 0.03 (0.4) | 0.006 | 0.391 | 0.566 | 0.020 |
| Fear/Phobia | 0.04 (0.6) | −0.09 (0.6) | −0.20 (0.6) | <0.001 | 0.016 | <0.001 | <0.001 |
| Externalizing/Behavior | −0.19 (1.1) | 0.06 (1.2) | 0.49 (1.2) | <0.001 | <0.001 | <0.001 | <0.001 |
| Psychosis Spectrum | 0.04 (0.8) | −0.10 (0.7) | 0.04 (0.8) | 0.011 | 0.982 | 0.011 | <0.001 |
Note. WRAT-4 = Wide Range Achievement Test-4th Edition.
a
Because of limited cell sizes, chi-square analysis compares 3 levels: alcohol non-users, use < 1–2 a week, and use ≥1–2 a week.
b
Factor scores from a bifactor model (Calkins et al., 2015) reflecting orthogonal dimensions of psychopathology, with higher scores indicating more symptoms.