In order to investigate the robustness of the results, we recalculated cost savings after changing the values of key parameters (see Table 3). Since the LOS results exhibited large variance and the differences were not significant, potential cost savings or additional investments were calculated based on the 95% confidence interval of the LOS results. Cost saving results were found not to be robust when subject
to changes in duration of hospital stay of negative patients. All other parameter changes did not significantly alter the results (Table 3). Changes in the quantity of samples processed per year did not have a significant effect on cost savings even though a small potential of economies of scale based on capital investment and staff training selleck screening library costs might be more significant for large laboratories with high sample turnover (Table 3). Due to the lack of statistical
significance and Neratinib purchase large range and variance in LOS data, the results of this study cannot definitely confirm that cost savings will be made by using PCR. However, a clear trend can be observed when results are tested for robustness indicating a high potential for savings (Table 3). Table 3 Parameter changes and their effect on potential cost savings achieved by routine real-time PCR compared to routine CCNA for Clostridium difficile testing Parameter Base case value Changed value (applied change) Cost saving/patient (£) LOS of CDI-positive patients (days) −4.88 −19.39 (lower bound Selleck Lumacaftor 95% CI) 2,545.73 LOS of CDI-positive patients (days) −4.88 9.62 (upper bound 95% CI) 2,036.68 LOS of CDI-negative patients (days) −7.03 −20.66 (lower bound 95% CI) 6,609.60
LOS of CDI-negative patients (days) −7.03 6.60 (upper bound 95% CI) −2,024.35 Cost of consumables and materials for testing (CCNA/PCR) (£) 1.57/33.51 0.79/16.75 (50% discount applied) 2,307.84 Number of samples processed per year 10,000 15,000 (+50%) 2,292.47 Number of samples processed per year 10,000 5,000 (−50%) 2,293.07 Percentage of positive samples 2.68 5.36 (+100%) 2,256.59 Percentage of positive samples 2.68 1.34 (−100%) 2,311.35 Assumption that all CCNA-negative patients will be tested twice Negative patients tested twice Negative patients tested once 2,302.55 Assumption that all CCNA-negative patients will be tested twice Negative patients tested twice Negative patients tested three times 2,283.19 CCNA cell culture cytotoxin neutralization assay, CDI Clostridium difficile infection, CI confidence interval, LOS length of hospital stay, PCR polymerase chain reaction Discussion Fast and accurate laboratory results have been suggested to impact patient management and infection control measures [20]. The high sensitivity and specificity of PCR-based assays for C.