Analytical approach:
The economic evaluation used data from a local hospital to determine the accuracy and clinical consequences of the diagnostic strategies, while a decision tree model was developed to compare the costs of the two options. The time horizon of the analysis appears to have been restricted to the admission period. The authors did not state explicitly which perspective was adopted.
Effectiveness data:
The clinical data were derived from records of patients admitted to a large local hospital where the new diagnostic approach was introduced in November 2004. Thus, clinical data 6 months before and 6 months after the implementation of the new real-time PCR approach were compared. Standard MRSA screening with culture was used as the 'gold' standard against which the accuracy of the new approach was tested. The main outcome measure was the incidence of nosocomial MRSA colonisation or infection due to transmission. A time series analysis was performed to assess the effect of using real-time PCR screening on the rate of nosocomial MRSA colonisation or infection.
Monetary benefit and utility valuations:
None.
Measure of benefit:
The key clinical end point was the mean monthly incidence of nosocomial MRSA colonisation or infection. It was not combined with the costs because of the cost-consequences design of the analysis.
Cost data:
The health services included in the analysis were the screening costs for nursing time, disposable laboratory supplies, and laboratory labour costs to process the specimens. The analysis also included the costs of contact precautions, lost revenue because of private room use of blocked beds, and housekeeping. The initial acquisition cost of the PCR equipment and training of technologists was not included. Resource use was based on patients’ records at the authors’ institution. The costs were derived from the hospital’s finance, admission, laboratory and housekeeping departments. The costs were in Canadian dollars (CAD) for the year 2005. The total costs of the two strategies were calculated using the decision tree model.
Analysis of uncertainty:
The issue of uncertainty was addressed in order to determine the impact of variations in incidence, sensitivity, specificity and screening compliance on the expected total costs of the two strategies. The sources of the alternative values were not stated clearly.