The Irish National Adverse Events Study 2 (INAES–2): Longitudinal Profiling of Adverse Events in Irish Hospitals and Provision of a Standardised Assessment Tool to the Irish Healthcare System.

International healthcare providers and institutions have shown little success in reducing AE rates by implementing large-scale evidence-based patient safety initiatives. In Ireland, the first Irish National Adverse Event Study (INAES) reported the AE rates in Irish hospitals to be 12.2.% (95% CI = 9.5% to 15.5%). This thesis examined the impact of recently implemented patient safety initiatives on the Irish healthcare system by comparing overall adverse event rates and preventable adverse event rates in Irish hospital inpatients between 2009 and 2015.

1605 admissions were reviewed after random selection from 8 hospitals in Ireland using the Harvard Medical Practise Study methodology of chart review. The adverse event prevalence for 2015 was 14% (95% CI = 10.4% – 18.4%), a non-statistically significant increase from 12.2% (95% CI = 9.5% – 15.5%), (p = 0.48) in 2009. The incidence density in 2015 was 10.4 events per 100 admissions (95% CI = 6.5 – 14.3), a non-statistically significant increase from 10.3 events per 100 admissions (95% CI = 7.2 to 13.4), (p =0.97) in 2009. The proportion of preventable adverse events was 7.4% (95% CI = 5.3% -10.5%) in 2015 and 9.1% (95% CI = 6.9%-11.9%), (p=0.33) in 2009. The incidence density of preventable adverse events was 5.6 (95% CI = 3.4-8 ) events per 100 admissions in 2015 and 7.7 (95% CI = 5.8-9.6), (p=0.23) events per 100 admissions in 2009. We subcategorised adverse events into groups which we thought would reflect changes made by patient safety initiatives.

It is possible that the downward trend seen in adverse events in the subcategories of adverse events represents a positive impact on patient care by the patient safety initiatives. This thesis highlights that adverse events remain a significant risk to patient safety in the Irish healthcare service requiring ongoing evidence-based approaches to remedy.