experimental and clinical studies remain an essential aspect of interpreting epidemiologic findings and such studies warrant further development. As has been argued before [46], one way to settle the question concerning a true causal impact of alcohol would be to conduct trials in the tradition of Kalichman and colleagues [239;240] with populations with a high risk of HIV infection, such as clients in clinics for sexually transmitted disease in countries with high HIV prevalence, and see if proven effective interventions for problem drinking do in fact lower the infection rate.
