RT Article T1 A qualitative exploratory study of substance abuse prevention outcomes in a heterogeneous prevention system JF Journal of drug education VO 29 IS 3 SP 217 OP 233 A1 Clapp, John D. A1 Early, Theresa J. LA English YR 1999 UL https://krimdok.uni-tuebingen.de/Record/1639611363 K1 Drogenprävention K1 Evaluation