This report describes part of the research conducted under Work Unit MODE, which examined methodological approaches in acquiring valid research data pertinent to critical social problems. It describes a study in which rates of nontherapeutic drug use obtained by a random urine screening program among Army personnel were compared with rates obtained by an anonymous self-report questionnaire. Procedural methodology in the urinalysis program was also examined. Questionnaire administration and urinalysis testing were conducted during the spring of 1973 on a sample of over 1,000 personnel assigned to five posts. The questionnaire was an inventory of drugs on which the subject indicated frequency of use during the previous three days. The field testing procedures in the urinalysis program were examined to determine variations in administration and to identify problems which could enable drug users to evade detection. As predicted, there was a discrepancy between the self-report rate of drug use and that found in urinalysis, with the self-report rate being much higher. Individual company commanders were particularly instrumental in determining the effectiveness of the urinalysis program. (Author)