Skip to main content
. Author manuscript; available in PMC: 2021 Oct 1.
Published in final edited form as: J Int Neuropsychol Soc. 2021 Jul;27(6):621–636. doi: 10.1017/S1355617721000631

Table 4.

Pre-and Post-initiation neuropsychological test scores for participants who initiated infrequent use of cannabis, moderately frequent use of cannabis, and use of alcohol but not cannabis.

Cognitive Measure Pre-Initiation Post-Initiation Group Differences

Infrequent Cannabis Users (IF) Moderately Frequent Cannabis users (MF) Alcohol-Only Users (AO) Infrequent Cannabis Users (IF) Moderately Frequent Cannabis Users (MF) Alcohol-only Users (AO) Pre-Initiation Only Nature of group differences

n=  29 18  39  29 18 39 -- --
RAVLT F (p)/ η p 2
Sum Total Correct: Trials 1–5 53.55 (1.49) 51.24 (1.93) 53.56 (1.29) 56.61 (1.63) 49.41 (2.10) 52.77 (1.44) 0.59/.574/.01
Trial 1 7.21 (.34) 6.06 (.44) 7.32 (.29) 7.55 (.29) 6.28 (.38) 7.09 (.26)
Trial 2 9.45 (.39) 9.05 (.51) 10.15 (.34) 10.56 (.41) 8.93 (.53) 9.77 (.36) N/A; values presented for descriptive purposes
Trial 3 11.51 (.39) 11.13 (.51) 11.38 (.33) 12.13 (.39) 10.86 (.50) 11.65 (.34)
Trial 4 12.61 (.38) 12.18 (.49) 11.99 (.33) 13.03 (.40) 11.26 (.52) 11.82 (.36)
Trial 5 12.77 (.32) 12.82 (.41) 12.73 (.27) 13.35 (.40) 12.13 (.52) 12.78 (.35)
New Learning (Average: Trial 1, ListB) 6.84 (.27) 5.73 (.35) 6.83 (.24) 6.87 (.23) 5.95 (.30) 6.72 (.21) 3.79/.027/.09 MF < AO; MF< IF
List B interference trial 6.47 (.30) 5.41 (.39) 6.23 (.26) 6.18 (.27) 5.62 (.34) 6.35 (.23) N/A; values presented for descriptive purposes
Immediate recall 11.20 (.46) 11.11 (.59) 11.38 (.40) 12.07 (.47) 10.79 (.61) 11.54 (.42) 0.08/.922/.00
30-minute delayed recall 10.93 (.51) 10.65 (.65) 11.19 (.44) 11.70 (.51) 9.54 (.66) 11.07 (.45) 0.24/.791/.01
Proportion of consolidated information (Delayed recall/Total correct trial 5) 0.86 (.03) 0.83 (.04) 0.88 (.03) .88 (.04) .74 (.05) .87 (.03) 0.52/.596/.01
Iowa Gambling Task
Total Adv-Disadv choices
13.1 (6.6) 8.1 (8.8) 19.5 (5.8) 28.42 (6.5) 20.81 (8.4) 24.10 (5.7) 0.62/.539/.02
Total Adv-Disadv choices for Trials 1–40: Decisions under ambiguity 1.50 (14.23) −1.29 (18.08) 2.00 (13.42) 2.79 (2.62) 0.74 (3.50) 0.26 (2.34) 0.00/.997/.00
Total Adv – Disadv choices for Trials 41–100: Decisions under risk 12.64 (24.07) 0.59 (33.72) 20.70 (27.25) 26.64 (4.46) 20.38 (5.98) 22.71 (4.00) 1.10/.339/.03

Notes. Estimated marginal means and standard errors are presented, controlling for parental education. Comparisons where p-values are statistically significant (p<.05) are bolded. Unless otherwise specified, values represent raw total correct scores for each trial of the RAVLT; raw scores were also used for IGT calculations.