Trends of drug and alcohol use in high-school youth in the US arc carefully monitored by studies such as Monitoring the Future (MTF).65 The 2007 MTF survey that, encompassed nearly 50 000 8th-, 10th-, and 12th-gra.de students in over 400 secondary schools nationwide continues to show a decline in illicit drug use across the US. However, this survey does not collect information on substance use disorders. The median estimate of alcohol or drug abuse or dependence in community surveys of adolescents is 5% with a range from 1% to 24%. 8 The results of the recent studies described in Table I yield similar estimates: 4.7%,13 5.3%, 14 2.4%, 12 and 1.7%.15 The lower rates in the latter two studies are likely to be attributed to the lower age range of these samples. For example, in the Great Smoky Mountains Survey, there was a dramatic increase in the rates of substance use disorders with age, with a 3-month prevalence rate of 0.3% at age 13,1.4% at age 14,5.3% at age 15, and 7.6% at age 16. Gender differences in prevalence rates
