Prioritizing treatment of rare diseases: a survey of preferences of Norwegian doctors.

Understanding doctors' preferences for prioritizing treatment of rare diseases can provide an important context for policy makers who must decide whether to exempt rare disease treatments, which are often quite expensive, from standard cost-effectiveness criteria. We surveyed a random sample of 551 Norwegian doctors in November 2011 and compared results to a similar survey of the Norwegian population. Respondents chose whether to prioritize treatment of patients with rare versus common diseases and then decided how to allocate funds between the two groups for each of two scenarios: (1) equal costs per person and (2) higher costs for the rare disease. Respondents were randomized to treatment costs for the rare disease in the second scenario that were either 8 or 25 times higher than treating the common disease. Except for different prevalence, the diseases were described identically. Doctors displayed no general preference for prioritizing treatment of rare diseases, but a large number favored the principle of reserving a small share of funds for rare disease patients. Doctors' responses differed significantly from those of the general population when the rare disease was more costly to treat. A larger share of doctors prioritized the common disease group for treatment while a smaller share expressed indifference. When dividing funds between the two patient groups, doctors allocated a smaller share of funds to the rare disease. Doctors were much less likely than the general population to divide funds equally between the groups. This study indicates that there is little support among Norwegian doctors for prioritizing the treatment of rare diseases.