Cost-effectiveness of ruling out deep venous thrombosis in primary care versus care as usual

Background: Referral for ultrasound testing in all patients suspected of DVT is inefficient, because 80-90% have no DVT. Objective: To assess the incremental cost-effectiveness of a diagnostic strategy to select patients at first presentation in primary care based on a point of care D-dimer test combined with a clinical decision rule (AMUSE strategy), compared with hospital-based strategies. Patients/Methods: A Markov-type cost-effectiveness model with a societal perspective and a 5-year time horizon was used to compare the AMUSE strategy with hospital-based strategies. Data were derived from the AMUSE study (2005-2007), the literature, and a direct survey of costs (2005-2007). Results of base-case analysis: Adherence to the AMUSE strategy on average results in savings of euro138 ($185) per patient at the expense of a very small health loss (0.002 QALYs) compared with the best hospital strategy. The iCER is euro55 753($74 848). The cost-effectiveness acceptability curves show that the AMUSE strategy has the highest probability of being cost-effective. Results of sensitivity analysis: Results are sensitive to decreases in sensitivity of the diagnostic strategy, but are not sensitive to increase in age (range 30-80), the costs for health states, and events. Conclusion: A diagnostic management strategy based on a clinical decision rule and a point of care D-dimer assay to exclude DVT in primary care is not only safe, but also cost-effective as compared with hospital-based strategies.