radiation therapy often produces considerable anxiety in patients. one reason for this anxiety is the uncertainty that often surrounds this treatment. since studies have shown that many patients experience the most distress during times that are uncertain, it is understandable that most individuals with cancer desire information about their disease, its treatment, side effects, etc. unfortunately, many patients do not receive the information necessary to dispel any of the preconceived misconceptions they may have about radiation therapy. the purpose of this study was to examine levels of radiation therapy knowledge and its influence on patients. patients who were about to receive radiation therapy for the first time at the thunder bay regional cancer centre were solicited as participants for this study. twenty-seven patients, 12 males and 15 females, agreed to participate in the present study. prior to their first meeting with a radiation therapist, participants were approached by a nurse, told about the study and asked to complete the state trait anxiety inventory, the general health and the radiation therapy questionnaire. the questionnaires were also completed by each subject on the last day of treatment. although state anxiety decreased significantly and radiation therapy questionnaire scores increased significantly at post­-treatment, this did not appear to be the result of any relationship between anxiety and radiation therapy knowledge (as measured by the radiation therapy questionnaire). however, this did indicate that patients acquired information about radiation therapy throughout the course of treatment. further psychometric examination of the radiation therapy questionnaire is necessary before using this measure as a screening instrument of radiation therapy knowledge.