['Effective communication between pharmacists and patients is a crucial factor in ensuring that medications are used properly. However, few studies have examined the contents of actual on-site communications between pharmacists and patients.', 'To identify the characteristics of and problems with routine communications between pharmacists and patients using the Roter Method of Interaction Process Analysis System (RIAS).', 'Conversations between pharmacists and simulated patients (SPs) were recorded and transcribed. Using the RIAS technique, their utterances were classified into 42 categories, and these were further divided into 11 clusters, such as open- and closed-ended questions, and analyzed. Furthermore, the influence that the different scenarios performed by the pharmacists may have had on the structure of their communication was investigated. All of the transcripts were double-coded by two certified coders.', "A total of 57 pharmacists took part in the study. The mean ratio of utterances made by SPs and pharmacists were 44% and 56%, respectively. The percentage of pharmacists' questions was more than double that of SPs' for both open- and closed-ended questions. In the influence that the different scenarios, the scenarios for patients with cancer was significantly higher ratio of utterances by the pharmacists."] Do analysis of pharmacist-patient communication using the Roter Method of Interaction Process Analysis System?