A number of studies have been published on the benefits of prophylactic treatment in adults with haemophilia. However, in many countries, it is considered as optional due to financial constraints. This survey was carried out to examine the long-term effects of prophylaxis and the continuing benefit of the treatment into adulthood. Self-assessed health-related data and the EQ-5D questionnaire measuring health utility were collected from 124 men (26.9 ± 4.6 years) from Canada (N = 40), France (N = 14), Ireland (N = 17), the Netherlands (N = 16), Poland (N = 24) and the UK (N = 13). The respondents were split into four groups: On-Demand,
