Objective: To evaluate the incidence of adverse events in Brazilian hospitals.
Design: Retrospective cohort study based on patient record review.
Setting: Three teaching hospitals in the State of Rio de Janeiro, Brazil.
Participants: Random sample (1103) of 27 350 adult patients admitted in 2003. Patients under 18 years old, psychiatric patients and patients whose length of stay was less than 24 hr were excluded, and obstetric cases were included.
Main outcome measure(s): Incidence of patients with adverse events; proportion of preventable adverse events; number of adverse events per 100 patients and incidence density of adverse events per 100 patient-days.
Results: The incidence of patients with adverse events was 7.6% (84 of 1103 patients). The overall proportion of preventable adverse events was 66.7% (56 of 84 patients). The incidence density was 0.8 adverse events per 100 patient-days (103 of 13,563 patient-days). The patient's ward was the most frequent location of adverse events (48.5%). In regard to classification, surgical adverse events were the most frequent ones (35.2%).
Conclusions: The incidence of patients with adverse events at the three hospitals was similar to that in international studies. However, the proportion of preventable adverse events was much higher in the Brazilian hospitals.