Table 7.
Marijuana Stroop task: multilevel model of marijuana high in relation to number of correct responses.
| Effects | Stroop number of correct responses (n=60) | |||||
|
|
Estimate | SE | 95% CI | P value | ||
| Fixed effects | ||||||
|
|
Person level (level 2) | |||||
|
|
|
Intercept | 29.03 | 0.53 | N/Aa | .001b |
|
|
|
Session | −0.00 | 0 | N/A | .001b |
|
|
|
Session2 (quadratic) | N/A | N/A | N/A | N/A |
|
|
|
Subjective high (PMc) | 0.37 | 0.13 | N/A | .003b |
|
|
|
Distraction (PM) | −0.82 | 0.41 | N/A | .046d |
|
|
|
Subjective high (PM) × distraction (PM) | −0.22 | 0.1 | N/A | .02d |
|
|
|
Gender (0=male, 1=female) | 0.11 | 0.07 | N/A | .14 |
|
|
|
Age (0=age 20) | −0.03 | 0.02 | N/A | .11 |
|
|
|
Full-scale IQ (0=IQ score of 110) | 0.02 | 0.01 | N/A | .02d |
|
|
Session level (level 1) | |||||
|
|
|
Subjective high (CCe) | −0.01 | 0.01 | N/A | .45 |
|
|
Distraction (CC) | −0.10 | 0.03 | N/A | .001b | |
|
|
Subjective high (CC) × distraction (CC) | −0.01 | 0.01 | N/A | .23 | |
| Random effects | ||||||
|
|
Level 1 residual variance | 0.51 | 0.01 | 0.49 to 0.54 | N/A | |
|
|
Intercept | 0.06 | 0.01 | 0.04 to 0.09 | N/A | |
aNot applicable.
bP<.01.
cPM: person mean scores, reflecting individual differences in subjective marijuana high or distraction across all sessions.
dP<.05.
eCC: constant-centered scores (centered at 0), reflecting session-to-session variation in scores or session-specific scores.