Table 3.

Estimated mean differences in IQ change between marijuana user groups

IQ subtestRFABMTFS
β (95% CI)Pβ (95% CI)P
Vocabulary−4.0 (−6.3 to −1.7)0.001−3.4 (−4.5 to −2.3)<0.001
Information−2.0 (−3.3 to −0.7)0.002
Similarities−0.1 (−2.8 to 2.5)0.932
Block Design0.2 (−2.0 to 2.5)0.833−0.6 (−1.8 to 0.6)0.293
Matrix Reasoning1.9 (−0.7 to 4.4)0.162
Picture Arrangement0.4 (−1.6 to 2.4)0.721
  • The coefficients denote the time-by-marijuana use interaction. Models are adjusted for age, sex, race, zygosity, SES, and MTFS cohort. N values are presented in Table S3. CI, confidence interval.