Two hundred and sixty-three ambulatory patients older than 21 years of age who were attending clinics at an oncology hospital in San Juan, Puerto Rico, were studied. They completed a questionnaire (BQ-PR) that measures 8 concerns about reporting pain and using analgesics, such as fears of addiction and tolerance and the belief that reporting pain can distract a physician from focusing on curing one's disease. Ninety percent of the patients had at least some concern about each of the 8 topics, and mean scores on the 8 subscales were near the midpoint on a 0-5 scale. There were significant inverse relationships between level of education, income, and BQ-PR total score. Those persons who experienced cancer-related pain on the day they completed the questionnaire were categorized as using adequate versus not adequate analgesic medication, a determination that was based on a comparison of their level of pain to the medication they were using. Those who were not using adequate analgesic medication had higher BQ-PR total scores than did those who were using adequate medication.