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. Author manuscript; available in PMC: 2019 Oct 1.
Published in final edited form as: Am J Psychiatry. 2018 Mar 21;175(10):1010–1021. doi: 10.1176/appi.ajp.2018.17070777

Table 4.

Zero-Inflated Poisson Regression Models of Marijuana Use Frequency Categories by Individual Subject Intercepts and Slopes from Multilevel Linear Models (MLM) of Orbital Frontal Cortex (OFC) Volume Residuals and OFC Thickness by Time-Varying CDI-C Anhedonia (N=137)

Estimate SE t p
Zero-inflated: marijuana abstinence
 Intercept −144.9453 2.6622 −54.45 <0.0001
 Intercept from MLM of OFC volume residuals −92.7248 174.4580 −0.53 0.5951
 Caucasian race 358.0357 153.6707 2.33 0.0198
 Male gender −156.1959 422.8904 −0.37 0.7119
 Age at last assessment −17.2575 50.3923 −0.34 0.7320
Continuous: frequency of use
 Intercept −6.3711 2.2635 −2.81 0.0049
 Intercept from MLM of OFC volume residuals −0.1871 0.0982 −1.91 0.0568
 Caucasian race 0.3343 0.3160 1.06 0.2901
 Male gender −0.1413 0.3121 −0.45 0.6507
 Age at last assessment 0.3381 0.1394 2.43 0.0153

Zero-inflated: marijuana abstinence
 Intercept 8631.4828 96.6595 89.30 <0.0001
 Slope from MLM of OFC volume residuals 2021.8787 610.7295 3.31 0.0009
 Caucasian race 984.1515 721.9290 1.36 0.1728
 Male gender 941.9319 743.8689 1.27 0.2054
 Age at last assessment −677.0268 46.0206 −14.71 <0.0001
Continuous: frequency of use
 Intercept −5.5617 2.4598 −2.26 0.0238
 Slope from MLM of OFC volume residuals −0.8607 1.7057 −0.50 0.6138
 Caucasian race 0.0247 0.2817 0.09 0.9301
 Male gender 0.3570 0.2889 1.24 0.2166
 Age at last assessment 0.2735 0.1519 1.80 0.0718

Zero-inflated: marijuana abstinence
 Intercept −977.6172 201.3198 −4.86 <0.0001
 Intercept from MLM of OFC thickness 262.9481 581.2684 0.45 0.6510
 Caucasian race −385.6956 48.2515 −7.99 <0.0001
 Male gender −62.2419 364.4789 −0.17 0.8644
 Age at last assessment −119.4254 420.1010 −0.28 0.7762
Continuous: frequency of use
 Intercept 2.1503 4.5573 0.47 0.6370
 Intercept from MLM of OFC thickness −0.6201 0.3927 −1.58 0.1143
 Caucasian race −0.3023 0.2952 −1.02 0.3058
 Male gender 0.2429 0.2893 0.84 0.4011
 Age at last assessment 0.2339 0.1513 1.55 0.1222

Zero-inflated: marijuana abstinence
 Intercept −1445.989 0.0404 −35772 <0.0001
 Slope from MLM of OFC thickness −12198 0.0069 0.00 <0.0001
 Caucasian race 82.9762 0.0404 2052.86 <0.0001
 Male gender 119.6468 0.0404 2960.08 <0.0001
 Age at last assessment −48.6716 0.6872 −70.83 <0.0001
Continuous: frequency of use
 Intercept −15.3208 3.5677 −4.29 <0.0001
 Slope from MLM of OFC thickness −54.2207 17.8396 −3.04 0.0024
 Caucasian race −0.0296 0.2821 −0.10 0.9165
 Male gender 0.4101 0.2912 1.41 0.1590
 Age at last assessment 0.3583 0.1444 2.48 0.0131