"Does drug testing prevent or inhibit student drug use? Members of the Supreme Court appear to believe it does. However, among the eighth-, 10th-, and 12-grade students surveyed in this study, school drug testing was not associated with either the prevalence or the frequency of student marijuana use, or of other illicit drug use. Nor was drug testing of athletes associated with lower-than-average marijuana and other illicit drug use by high school male athletes. Even among those who identified themselves as fairly experienced marijuana users, drug testing also was not associated with either the prevalence or the frequency of marijuana or other illicit drug use."

Source

Yamaguchi, Ryoko, Lloyd D. Johnston & Patrick M. O'Malley, Relationship Between Student Illicit Drug Use and School Drug-Testing Policies," Journal of School Health, April 2003, Vol. 73, No. 4, p. 164.
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