How should we assess risk behaviour when determining donor deferral? Reflections on the MSM deferral.

Concerns are increasingly being raised in a number of countries in relation to the behavioural donor criteria and in particular the on-going permanent exclusion of men who have had sex with other men (MSM). The justification for this is broadly linked to the use of risk models. Generally current exclusion criteria are broadly defined and indirectly it might be argued that this leads to exclusion based on sexual orientation. Available data indicates compliance issues with the exclusion and recent reviews in Europe have recommended that further research in this area is needed before any change in the current permanent exclusion should be made. Lobby groups however promote a more targetted approach to behavioural criteria. Firm data to support this is however currently lacking. There are a number of possible approaches to assessing risk including the period since the activity took place, the number of partners in a given period, the type of sex act or a combination of these factors. Definition of an optimal approach will need to consider both the sensitivity and specificity of the intervention along with an assessment of ease and consistency of application.