Drug Testing as Predictor of Drug Use
"Similar to results for marijuana use, drug testing of any kind and drug testing for cause and suspicion were not significant predictors for use of other illicit drugs among students in grades eight, 10, and 12. Within the high school subsamples, use of illicit drugs among high school male athletes and current marijuana users was not significantly different based on drug testing at the school. Even after controlling for student demographic characteristics, drug testing was not a significant predictor for other illicit drug use in any of the samples."
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. 163.