[Root cause analysis: evaluation of medication errors at a university hospital].

The objectives of this study were to identify and analyze the types of medication errors observed in doses prepared and administered differently from those prescribed. It is a descriptive study using the root cause analysis method, in which a secondary analysis of data from a previously existing investigation was performed. In the study, 74 medication errors were identified during medication preparation and administration by the nursing staff. Dose errors (24.3%), schedule errors (22.9%) and unauthorized medication administration errors (13.5%) were the most frequent. Hence, medication errors were identified, and root cause analysis was performed, leading to the identification of multiple factors that contributed to error occurrence. Strategies and recommendations were presented for the prevention of errors.