AN ETHNOGRAPHIC APPROACH TO TARGETED SAMPLING - PROBLEMS AND SOLUTIONS IN AIDS-PREVENTION RESEARCH AMONG INJECTION-DRUG AND CRACK-COCAINE USERS

Recruiting large samples from ''hidden populations'' of injection drug and crack-cocaine users who are not in drug treatment has been a troubling methodological problem that has increased in significance in the face of the AIDS pandemic. This article describes a sampling strategy developed for AIDS prevention research in Montgomery County (Dayton) Ohio that combines targeted sampling with the systematic derivation of proportional sampling quotas. The ethnographic mapping of drug use indicators by outreach workers plays a key role in the sampling design. The triangulation of independent drug use indicators enables us to estimate the relative density of drug users throughout the county and generate proportional sampling quotas for three sampling zones. The sampling strategy has a range of potential applications.