RESUMEN
OBJECTIVES: To investigate and identify priority areas and issues of patient safety and analyse which patient and health care characteristics are related to Adverse Events (AE). METHODS: Retrospective cohort study to identify AE reviewing medical records of in-patients. Information was obtained from all patients attended between 15 and 30 November 2009 in eight facilities committed to the project. RESULTS: Of the 927 patients, 40 patients had any injury, of which 23 were related to healthcare. Thus, the percentage of patients with any AE associated with health care was 2.48% (95%CI, 1.43%-3.54%). Age, comorbidity and use of invasive devices explained the occurrence of an AE. Of these, 33.3% (8 AE) were considered slight, 33.3% (8) moderate and 33.3% (8) severe. Half (50%) of AE were considered preventable. CONCLUSIONS: The frequency of AE found was low, possibly due to study design and the idiosyncrasy of the patients: age, comorbidity and use of invasive devices. The AE found have a similar impact and preventability as those identified in public sector.