PDF - http://www.ncjrs.org/pdffiles1/ojjdp/203934.pdf
"'The study confirms a high rate of drug use among juvenile detainees
and identifies detainees who require special attention. The authors conclude that because cannabis use is so common and often leads to more serious drug use, most youth entering detention can be considered at risk of developing substance abuse problems. The study�s findings indicate that the best approach to detecting substance abuse is to combine self-reporting with urinalysis and also use other resources such as treatment and drug arrest histories and information from families and schools."
