Physicians' preferences towards coagulation factor concentrates in the treatment of Haemophilia with inhibitors: a discrete choice experiment

Summary.  This study sought to identify attributes of treatment important to haematologists in making their decisions regarding optimal care for inhibitor patients in the United States. A conjoint analysis using a discrete choice experiment was conducted to elicit factors that are most important to haematologists. Twelve product attributes were chosen based on published literature and expert opinion: risk of human viral infections, possibility that the titre of the inhibitor may rise, reduction in the likelihood of dose-related thromboembolic events, the number of infusions required to stop haemorrhage, infusion preparation time, infusion time, infusion volume, time required to stop bleeding, time required to alleviate pain, prophylaxis use, ability to undergo major surgery and cost of medications. Thirty haematologists completed the questionnaires via face-to-face interviews at a scientific meeting in April 2006. Data were analysed using a multinomial logit model to obtain the relative importance of each attribute. Responding haematologists had considerable experience in treating haemophilia patients with inhibitors (average : 13 ± 9  years). 'Time required to stop bleeding' was the most important factor affecting treatment decisions [relative importance (RI) = 16.3%]. Physicians also preferred treatments that resulted in quick pain relief [RI = 12.9%], reduced the possibility that the titre of inhibitor may rise [RI = 12.8%], required fewer number of infusions to stop a haemorrhage [RI = 12.7%] and reduced the risk of human viral infection [RI = 10.8%]. This study revealed that certain clinical outcomes attributes are the most preferred and important. These findings can assist decision makers in their assessments of optimal first-line care.