How do we know whether a primary prevention program on drug abuse works or does not work?

Primary prevention of drug abuse is defined as a systematic effort through which curiosity-oriented drug experimenters are kept from becoming regular drug users. Following this definition, a model program entitled Ombudsman is evaluated. The hypothesis tested is: The proportion of students who no longer use drugs will be greater among those who have participated in the Ombudsman program than among those who have not. Some of the findings are: (1) the program is most effective with regard to "hard' drugs (greater than .001), but not with "social' drugs; (2) the program impact is most effective among younger students (p greater than .01).