Epidemiological research on cocaine use in the USA.

In the study of cocaine, epidemiology offers a way to reckon the experience of human populations, from time to time, from region to region, from community to community, and from group to group. Continuing surveillance of cocaine experiences in diverse segments of the United States population has allowed us to plot the course of our most recent cocaine epidemic in more detail than in the past. Still, much remains to be learned about the dynamics of the cocaine epidemic before public health agencies or anyone else should ride to glory on the descending limb of this epidemic curve. Beyond basic surveillance, epidemiology has the capacity to teach us about the conditions under which human cocaine use starts, is maintained, and stops, including the array of perceived and actual consequences of cocaine use that may determine specific patterns of use. In this respect, there is some value in making a chronicle of cocaine users' life experiences, with a comparison to the life experiences of others. However, the perceptions of cocaine users do not always map onto observations made under controlled conditions of laboratory research. Finally, it is not essential for epidemiology to rely solely upon what individuals perceive and report as causal linkages between cocaine use and their other life experiences. One effective alternative is to use the epidemiological case-control method and related strategies to probe suspected causal linkages involving cocaine. As demonstrated in recent research, these strategies have a resolving power that goes beyond that of standard epidemiological survey reports. Of course, the resulting epidemiological evidence does not stand alone. Rather, it complements laboratory and clinical research, giving a more complete view of cocaine's impact on human health.