Studying crack abusers: strategies for recruiting the right tail of an ill-defined population.

This study attempts to better understand a limited segment of the drug-abusing population, especially individuals who repeatedly use crack and other drugs. This article addresses the methodological strategies and underlying paradigms informing the recruitment of hard-to-reach and ill-defined subpopulations of crack abusers and noncrack drug abusers. Subjects were recruited from diverse social contexts: streets or communities where most drug users do their business, arrested persons who were released, jail inmates, probationers and parolees, prison inmates, and treatment settings. A systematic comparison of subject attributes across recruitment locales and with other, similar target groups is presented. The utility and external comparability of the recruitment techniques are supported by the findings.