Table 4 Outcome measurements [1,11]

   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 was caused by health care management or the disease process a 6-point scale was used:

   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 was measured on a 6-point scale, grouped into three categories:

No preventability

   1. (Virtually) no evidence for preventability

Low preventability

   2. Slight to modest evidence of preventability

   3. Preventability not quite likely (less than 50/50, but 'close call')

High preventability

   4. Preventability more than likely (more than 50/50, but 'close call')

   5. Strong evidence of preventability

   6. (Virtually) certain evidence of preventability

Timing of the adverse events in relation to index hospital admission.

The index hospital admission was the admission sampled. Adverse events were recorded if they occurred during the index admission and that were detected during or after the index admission over the following 12-month period. Or adverse events that were related to hospital admissions within the 12-month preceding the index admission but were not detected until the index admission (Figure 2).