Necessity under construction - societal weighing rationality in the appraisal of health care technologies.

Health care coverage decisions may employ many different considerations, which are brought together across two phases. The assessment phase examines the available scientific evidence, such as the cost-effectiveness, of the technology. The appraisal then contextualises this evidence to arrive at an (advised) coverage decision, but little is known about how this is done.In the Netherlands, the appraisal is set up to achieve a societal weighing and is the primary place where need- and solidarity-related ('necessity') argumentations are used. To elucidate how the Dutch appraisal committee 'constructs necessity', we analysed observations and recordings of two appraisal committee meetings at the National Health Care Institute, the corresponding documents (five), and interviews with committee members and policy makers (13 interviewees in 12 interviews), with attention to specific necessity argumentations.The Dutch appraisal committee constructs necessity in four phases: (1) allowing explicit criteria to steer the process; (2) allowing patient (representative) contributions to challenge the process; (3) bringing new argumentations in from outside and weaving them together; and (4) formulating recommendations to societal stakeholders. We argue that in these ways, the appraisal committee achieves societal weighing rationality, as the committee actively uses argumentations from society and embeds the decision outcome in society.