Delphi approach to select rare diseases for a European representative survey: the BURQOL-RD study

Objectives: The BURQOL-RD project is intended to develop a disease based model capable of quantifying the socio-economic burden and health-related quality of life for patients with rare diseases (RDs) and their caregivers in Europe. We described the methodology used to select a set of 10 RDs to be approached in a pilot study. Methods: BURQOL-RD project includes 23 partners from 8 European countries: Spain, UK, France, Germany, Sweden, Italy, Hungary and Bulgaria. A two-round Delphi panels in combination with Carroll diagram was used to generate consensus in the selection of the 10 RDs among the project participants. Results: The two Delphi rounds yielded a prioritised list, to which the Carroll diagram was applied, taking into account three determinants: prevalence, availability of effective treatment and need for carer. The final set of RD to be studied was obtained: cystic fibrosis, Prader-Willi syndrome, haemophilia, duchenne muscular dystrophy, epidermolysis bullosa, fragile X syndrome, scleroderma, mucopolysaccharidosis, juvenile idiopathic arthritis and histiocytosis. Conclusions: This methodology permitted the generation of an equilibrated set of RDs for the pilot study of BURQOL-RD project. The model will be suitable for application in a wide range of RDs.