Introduction
The earlier an adolescent begins regular drinking of
alcohol the higher the level of misuse (Hawkins et al
1997) and alcohol dependence (Grant and Dawson 1997)
and the greater the severity and persistence of problems
with illicit drugs (Kandel et al 1992; Robins and Przybeck
1985). Hawkins et al (1997) recruited children between the
ages of 10 and 11 and observed them for 7 years, finding
greater misuse at ages 17 and 18 among those with earlier
alcohol initiation. Using a large-scale population sample,
Grant and Dawson (1997) showed that the age of onset of
regular drinking predicted the likelihood of adult alcohol
dependence. For those individuals younger than 14 years,
the rate was 40%; for those age 20 and older, it was only
10%. Conversely, abstinence at age 16 was found to
predict limited use at age 23 in a national representative
British study, whereas regular drinking at age 16 increased
the risk fourfold for heavy drinking at age 23 (Ghodsian
and Power 1987).