Background Interest in patient safety (PS) is growing exponentially, fuelled by epidemiological research unveiling the extent of unsafe care. However, there is little information about the frequency of harm in developing and transitional countries. To address this issue, the authors performed a study known as the Iberoamerican Adverse Event Study, through a collaborative between the governments of Argentina, Colombia, Costa Rica, Mexico and Peru, the Spanish Ministry of Health, Social Policy and Equality, the Pan American Health Organization and the WHO Patient Safety.

Methods The study used a cross-sectional design, involving 58 hospitals in the five Latin American countries, to measure the point prevalence of patients presenting an adverse event (AE) on the day of observation. All inpatients at the time of the study were included.

Results A total of 11 379 inpatients were surveyed. Of these, 1191 had at least one AE that the reviewer judged to be related to the care received rather than to the underlying conditions. The estimated point prevalence rate was 10.5% (95% CI 9.91 to 11.04), with more than 28% of AE causing disability and another 6% associated with the death of the patient. Almost 60% of AE were considered preventable.

Conclusions The high rate of prevalent AE found suggests that PS may represent an important public-health issue in the participating hospitals. While new studies may be needed to confirm these results, these may already be useful to inspire new PS-improvement policies in those settings.