Aims The aim of the present study was to determine the mediating role of affiliation with cannabis-using peers in the pathways
from various dimensions of temperament to life-time cannabis use, and to determine if these associations also contributed
to the development of regular cannabis use.
Methods Objectives were studied using data from 1300 participants of the Tracking
Adolescents' Individual Lives Survey (TRAILS), a large, general population study of Dutch adolescents. We used parent-reports
on the Early Adolescent Temperament Questionnaire to assess the dimensions of high-intensity pleasure, shyness, fearfulness,
frustration and effortful control at age 10-12 years. By means of self-reports, life-time and regular cannabis use were determined
at age 15-18 years, and proportion of substance-using peers was determined at ages 12-15 and 15-18 years. Models were adjusted
for age, sex, intelligence and parental cannabis use.
Results High-intensity pleasure [odds ratio (OR) = 1.09, 95% confidence
interval (CI) = 1.05-1.13] and effortful control (OR = 0.92, 95% CI = 0.89-0.96) affected the risk for life-time cannabis
use through their influence on affiliation with cannabis-using peers. Shyness affected this risk independently from peer cannabis
use. Only the pathway from effortful control was associated additionally with the development of regular cannabis use (OR
= 0.93, 95% CI = 0.89-0.98).
Conclusions Peer cannabis use and, to a lesser extent, certain temperamental characteristics
affect an adolescent's risk of cannabis use, and should be considered in prevention programmes. We recommend future research
to focus upon factors that potentially modify the association between temperament, affiliation with cannabis-using peers and