Economic evaluation of an expert examiner and different ultrasound models in the diagnosis of ovarian cancer.

The Risk of Malignancy Index (RMI) is commonly used to diagnose adnexal masses. The aim of the present study was to determine the cost-effectiveness of the RMI compared with subjective assessment (SA) by an expert and the following novel ultrasound models: Cost-effectiveness and budget impact analyses were performed from a societal perspective. A decision tree was constructed, and short-term costs and effects were examined in women with adnexal masses. Sensitivity, specificity and the costs of diagnostic strategies were incorporated. Incremental cost-effectiveness ratios were expressed as costs/additional percentage of correctly diagnosed patients. Probabilistic and deterministic sensitivity analyses were performed. Effectiveness was highest for SA (90.7% [95% confidence interval = 77.3-100]), with a cost saving of 5.0% (-€398 per patient [-€1403 to 549]) compared with the RMI. The costs of SR + SA were the lowest (€7180 [6072-8436]), resulting in a cost saving of 9.0% (-€709 per patient [-€1628 to 236]) compared with the RMI, with an effectiveness of 89.6% (75.8-100). SR + SA showed the highest probability of being the most cost-effective when willingness-to-pay was <€350 per additional percentage of correctly diagnosed patients. The RMI had low cost-effectiveness probabilities (<3%) and was inferior to SA, SR + SA and LR2. Budget impact in the Netherlands compared with that of the RMI varied between a cost saving of €4.67 million for SR + SA and additional costs of €3.83 million when implementing ADNEX (cut-off: 10%). The results were robust when tested in sensitivity analyses. Although SA is the best strategy in terms of diagnostic accuracy, SR + SA might be preferred from a cost-effectiveness perspective.