About the research
Drug abuse and the use of illegal drugs are a consistent topic of discussion in Britain today as academics, politicians, pundits and concerned citizens debate what drives a person to drug abuse and what kind of person is likely to become a drug user. Recently, studies have linked high IQ scores in childhood to excessive alcohol intake and a dependence on alcohol in later life. Can such a link be discovered for use of illegal drugs such as cannabis, cocaine and ecstasy? White and Batty have investigated this question using 1970 British Cohort Study data and found that those children with higher IQs measured at 5 or 10 years of age did have increased illegal drug use later in life. This is the largest study on this relationship to date, and it took into account the socio-economic position of the participants over the course of the study (1970-2000), the presence or absence of any psychological distress at age 16, and education level. The study found that participants with a higher IQ score in childhood were more likely to use drugs as adults, than those with IQ scores in the lower range. These factors were independent of the influence of social class and education. They also found a stronger association amongst women than men.
Methodology
This research used the four follow-up surveys from 1975 (age 5), 1980 (age 10), 1986 (age 16), and 2000 (age 30). The researchers applied a multivariate logistical regression analysis which allowed them to simultaneously analyse multiple variables while attempting to find the association between childhood IQ and the risk of using illegal drugs as an adult. Participants were chosen from the larger study if they had had IQ scores measured at 5 or 10 years. The study included measures of these participants’ lifetime use of cannabis and cocaine, parental social class, presence of any psychological stress at age 16 years, use of cannabis, cocaine, amphetamines, ecstasy and polydrug (more than three drugs) use in the last 12 months, and social class, educational level, and gross monthly income at age 30. These variables were not found to have an impact on the presence of drug use in relation to participants’ childhood IQ.
Publications
Findings were published as Intelligence across childhood in relation to illegal drug use in adulthood: 1970 British Cohort Study in the Journal of Epidemiology and Community Health, November 2011.