Economic evaluation of a clinical protocol for diagnosing emergency patients with suspected pulmonary embolism

BACKGROUND The objective of this paper is to estimate the amount of cost-savings to the Australian health care system from implementing an evidence-based clinical protocol for diagnosing emergency patients with suspected pulmonary embolism (PE) at the Emergency department of a Victorian public hospital with 50,000 presentations in 2001-2002. METHODS A cost-minimisation study used the data collected in a controlled clinical trial of a clinical protocol for diagnosing patients with suspected PE. The number and type of diagnostic tests in a historic cohort of 185 randomly selected patients, who presented to the emergency department with suspected PE during an eight month period prior to the clinical trial (January 2002-August 2002) were compared with the number and type of diagnostic tests in 745 patients, who presented to the emergency department with suspected PE from November 2002 to August 2003. Current Medicare fees per test were used as unit costs to calculate the mean aggregated cost of diagnostic investigation per patient in both study groups. A t-test was used to estimate the statistical significance of the difference in the cost of resources used for diagnosing PE in the control and in the intervention group. RESULTS The trial demonstrated that diagnosing PE using an evidence-based clinical protocol was as effective as the existing clinical practice. The clinical protocol offers the advantage of reducing the use of diagnostic imaging, resulting in an average cost savings of at least $59.30 per patient. CONCLUSION Extrapolating the observed cost-savings of $59.30 per patient to the whole of Australia could potentially result in annual savings between $3.1 million to $3.7 million.