The studies were conducted independently in each country between 1990 and 1992. Results revealed that the lifetime prevalence of cocaine or coca paste use did not vary appreciably from country to country and were considerably lower than the 11.7 percent reported in the United States in 1991. The lifetime prevalence of use in these five countries was between 0.8 percent and 3 percent. The highest prevalence of use occurred among those who were middle-aged, middle-class, males, people who had finished high school, those who had high income, and urban residents. The most frequent age of first use was 15-24 years. Findings indicated that the use of coca and its derivatives is a public health problem that is affecting a productive segment of the population of the Andean region. Tables, figures, and 39 references (Author abstract modified)