Definitions for haemophilia prophylaxis and its outcomes: the Canadian consensus study

The creation of acceptable standard definitions for terms used in the care and assessment of haemophilia patients has become increasingly important, as a growing number of international clinical studies have been initiated. The Delphi approach has been used in health research to reach consensus in large groups and can be used to develop definitions by using several iterations of surveys eliciting opinions from specialists in the field. Three consecutive surveys were designed based on the Delphi approach and distributed to specialist physicians, nurses and physiotherapists in order to develop definitions for seven haemophilia terms: 'primary prophylaxis', 'secondary prophylaxis', 'target joint', 'joint bleed', 'significant soft-tissue bleed', 'superficial soft-tissue bleed' and 'mucosal bleed'. Suggestions were solicited, compiled into a subsequent survey and fed back to the group to rank-order the importance of each suggested component of the definition. Final definitions were created using the top-ranked suggestions and sent back to the experts for approval. Five of the seven terms were highly endorsed with greater than 90% agreement. Some differences in agreement were found when analysed by profession. Haemophilia terms were successfully defined using the Delphi approach. Further refinement from members of the international haemophilia community will ensure that comprehensive standard definitions can be used in multicentre studies in the future.