Inhospital the blood transfusion process consists of many phases: ordering the blood product, analysis of the blood sample, delivery, transport and storage of the blood product and administration. In each of these phases (near) accidents may occur. A severe transfusion incident refers to the transfusion of a wrong blood product, whereas a near miss is detected before transfusion.

In 2010 the University Hospitals Leuven introduced a new electronic patient incident report system for transfusion events.

In this study the investigators will analyze the reported blood transfusion events to detect the most common causes of blood transfusion events and the weakest link in the blood transfusion chain.

A retrospective survey will be conducted of all transfusion events reported in the University Hospitals Leuven between January 2011 and July 2012. Both severe accidents and near misses will be included.

Data will be drawn from the incident report system. Data concerning the number of transfused blood products will be required from the Medical Administration Service.

Events will be classified according to the severity and the cause of the event. The different settings where the events took place will be compared using a chi-square test (p<0,05).

Inclusion Criteria:

• all transfusion events reported in the University Hospitals Leuven between January 2011 and July 2012
• Both severe accidents and near misses were included

Exclusion Criteria:

• Transfusion reactions

All patients in a university hospital which experienced a transfusion event