Exploration of the functions of health impact assessment in real-world policymaking in the field of social health inequality: towards a conception of conceptual learning.

With the implementation of health impact assessment (HIA)'s conceptual model into real-world policymaking, a number of fundamental issues arise concerning its decision-support function. Rooted in a rational vision of the decision-making process, focus regarding both conceptualisation and evaluation has been mainly on the function of instrumental policy-learning. However, in the field of social health inequalities, this function is strongly limited by the intrinsic 'wickedness' of the policy issue.