Assessing critical care unit performance: a global measure using graphical analysis

Outcome measurement in critical care is difficult because of the wide variety of patients treated and the diverse therapeutic options and pathways available. Individual outcome measures for critical care are available but are naturally limited to only a single aspect of performance. Most importantly, better performance in one aspect of care may compromise the standard of care in another. A global measure of performance would be helpful. For the year 1999-2000, the five hospitals in the East Anglian Critical Care Network provided data on capacity, workload and performance. The data was transformed and displayed graphically on a radar chart so that the area of the polygon within the radar chart was proportional to each unit's overall performance. The results from the five hospitals suggest that there is little overall difference in the units' global performance but the graphical representation highlighted some individual deficiencies. Graphical analysis of complex processes such as critical care delivery may facilitate performance assessment, providing that the measures chosen, weightings assigned and scales used are standardised with care.