Table 2.
Variable Mean (SD) |
Healthy controls | Early MJ onset (before age 16) | Late MJ onset (age 16 or after) |
Sig 2-tailed p (η2) |
Sheffé comparisons sig 2-tailedp |
||
---|---|---|---|---|---|---|---|
E vs HC | L vs HC | E vs L | |||||
N | 34 (21 M, 13 F) | 24 (21 M, 3 F) | 26 (21 M, 5 F) | – | – | – | – |
Handedness | 32R, 2L | 21R, 3L | 25R, 1L | – | – | – | – |
% Caucasian | 65.00% | 73.33% | 66.67% | – | – | – | – |
Age | 24.47 (6.49) | 23.67 (7.26) | 24.27 (6.79) | NS | NS | NS | NS |
Full Scale IQ (FSIQ) | 123.15 (10.94) | 115.38 (17.02) | 119.58 (12.93) | NS | NS | NS | NS |
Past month days of alcohol use | 5.35 (5.56) | 5.92 (5.01) | 6.06 (6.05) | NS | NS | NS | NS |
FTNDa | 0.00 (0.00) | 0.29 (0.91) | 0.08 (0.39) | NS | NS | NS | NS |
MJ age of onset (years) | – | 14.17 (1.31) | 17.58 (1.94) | <.001(.521) | – | – | – |
MJ smokes/week | – | 24.51 (21.25) | 13.53 (7.74) | .022(.109) | – | – | – |
MJ grams/week | – | 14.57 (16.97) | 5.64 (4.54) | .016(.119) | – | – | – |
MJ duration of use (years) | – | 9.50 (7.80) | 6.69 (5.68) | NS | – | – | – |
Urinary THC concentration | – | 784.63 (1430.96) | 620.22 (916.38) | NS | – | – | – |
BIS-11b |
Sig 1-tailed p (η2) |
Sheffé comparisons sig 1-tailedp | |||||
Attention | 14.61 (0.56) | 16.81 (0.68) | 16.52 (0.63) | .012(.097) | .026 | .042 | NS |
Motor | 19.58 (0.83) | 22.91 (1.01) | 22.36 (0.92) | .011(.099) | .023 | .045 | NS |
Non-planning | 23.19 (0.85) | 26.67 (1.04) | 26.56 (0.96) | .006(.113) | .021 | .019 | NS |
Total | 57.39 (1.75) | 66.38 (2.14) | 65.44 (1.96) | .001(.158) | .004 | .007 | NS |
Stroop Color Word Test |
Sig 1-tailed p (η2) |
Sheffé comparisons sig 1-tailedp | |||||
Color naming | |||||||
Percent accuracy | 94.28 (5.68) | 91.59 (10.54) | 92.98 (8.02) | NS | NS | NS | NS |
Omissions | 4.53 (5.79) | 7.38 (11.22) | 6.08 (8.86) | NS | NS | NS | NS |
Commissions | 2.09 (2.31) | 2.71 (2.48) | 2.35 (2.33) | NS | NS | NS | NS |
Word reading | |||||||
Percent accuracy | 99.07 (1.81) | 97.95 (3.31) | 98.37 (2.51) | NS | NS | NS | NS |
Omissions | 0.56 (1.31) | 1.04 (2.68) | 0.77 (1.61) | NS | NS | NS | NS |
Commissions | 0.38 (0.82) | 1.42 (1.95) | 1.19 (1.63) | .011(.091) | .018 | NS | NS |
Interference | |||||||
Percent accuracy | 96.69 (5.33) | 88.88 (14.31) | 95.72 (7.06) | .003(.212) | .005 | NS | .019 |
Omissions | 0.79 (1.61) | 4.42 (7.96) | 1.46 (3.14) | .007(.099) | .010 | NS | .046 |
Commissions | 1.59 (2.86) | 3.46 (3.82) | 1.58 (2.34) | .021(.075) | .037 | NS | .048 |
Fagerstrom Test For Nicotine Dependence.
Barratt Impulsiveness Scale.