Editor of Clinical Guidelines, Directorate of Health, Iceland
Affordability describes the means a nation / health care system has at its disposal and could allocate to a particular purchase (service). This has nothing to do with the actual decision whether to purchase or not, as this would depend on, amongst other things, the relative and absolute values of the goods.
In a system, like in Iceland, where the social security service is the main purchaser (apart from hospitals) and has a fixed budget for a defined population, affordability could be affected by changes in other services (reduced or increased demand in one sector could affect another – drug expenditure vs physician services).