This was a landmark patient safety study, jointly carried out by the Royal College of Physicians of Ireland and the Royal College of Surgeons in Ireland.

We wanted to see how common adverse events were in acute Irish hospitals before the establishment of the National Clinical Programmes, and what form they took. We also aimed to identify specific patient safety problems.

Adverse events are unintended injuries or complications that are caused by the management of a patient’s healthcare, rather than by the patient’s underlying disease. Such complications can lead to death, disability or a prolonged hospital stay.

The project was funded by the Health Research Board and commenced in 2013. The study was published in BMJ Quality & Safety in February 2016. The main findings were:

• Numbers: The study found that one-in-eight patients (12.2%) experienced an adverse event as a result of hospital care in 2009. This is broadly in line with international figures where adverse events rates ranged from 3-17% of hospital admissions, depending on how each country defined adverse events.
• Impact: Almost 7 in 10 of these were rated as having a mild to moderate impact on the patient (ranging from no physical impairment at discharge to moderate impairment but recovery within 6 months), a further 5% caused moderate impairment with disability lasting 6 to 12 months, 10% caused permanent impairment (disability lasting greater than a year), 11% the level of impairment was not recorded at the time of discharge and 7% contributed to death.  Over 70% of the events were considered preventable.
• Type: The adverse events included: readmission with additional symptoms, hospital acquired infections, delayed diagnosis, and surgical adverse events.
• Risk: Adverse event risk was higher in admissions for surgical procedures. 
• Cost: The estimated annual cost of adverse events in 2009 was €194 million.
• Age: The average age of patients with an adverse event was significantly higher than those without (61.8 years versus 55.4 years).  There was an 18% increase in the risk of an adverse event with every 10 years added to the patient’s age.
• Gender: No significant difference was reported between men and women in this study.