Table 3 Outcome measures

Determination of the presence of an adverse event is based on three criteria [4, 5, 10]

1.

  an unintended (physical and/or mental) injury which

2.

  results in temporary or permanent disability, death or prolongation of hospital stay, and is

3.

  caused by health care management rather than the patient's disease

To determine whether the injury is caused by health care management or the disease process a 6-point scale will be used [4, 5, 10]:

1.

  (Virtually) no evidence for management causation

2.

  Slight to modest evidence of management causation

3.

  Management causation not likely (less than 50/50, but 'close call')

4.

  Management causation more likely (more than 50/50, but 'close call')

5.

  Moderate to strong evidence of management causation

6.

  (Virtually) certain evidence of management causation

The degree of preventability of the adverse events is measured on a 6-point scale, grouped into three categories [4, 5, 10]:

No Preventability

1.

  (Virtually) no evidence for management causation

Low Preventability

1.

  Slight to modest evidence of management causation

2.

  Management causation not likely (less than 50/50, but 'close call')

High preventability

1.

  Management causation more likely (more than 50/50, but 'close call')

2.

  Moderate to strong evidence of management causation

3.

  (Virtually) certain evidence of management causation

Severity categories of AE’s based on the classification of the National Coordinating Council for Medication Error Reporting and Prevention (NCC MERP)[20]. An error occurred that:

–

  Category E: contributed to or resulted in temporary harm to the patient and required intervention

–

  Category F: contributed to or resulted in temporary harm to the patient and required initial or prolonged hospitalization

–

  Category G: Contributed to or resulted in permanent harm

–

  Category H: Required intervention to sustain life

–

  Category I: Contributed to or resulted in the patient’s death (mortality rate)

Classification of the type of AE’s[4, 19]

–

  Operative: an adverse event in relation to a surgical procedure or anesthesia.

–

  Procedural: an adverse event in relation to a non-surgical procedure such as insertion of a central venous line, nasogastric tube, cardiac catheterization, etc.

–

  Anesthesia: an adverse event in relation to anesthesia.

–

  Diagnostic: an adverse event arising from a delayed or wrong diagnosis.

–

  Therapeutic: an adverse event arising when a correct diagnosis was made but there was incorrect therapy or a delay in treatment.

–

  Drug/intravenous fluid: an adverse event arising from the incorrect administration of a drug or intravenous fluid.

–

  System issue: an adverse event in relation to problems with hospital processes such as nosocomial infection or equipment malfunction.