The role of budget impact in reimbursement decisions in The Netherlands: interviews with decision-makers and pharmaceutical industry representatives

Economic evaluations of health technologies increasingly encompass a cost-effectiveness analysis (CEA) and a supplementary budget impact analysis (BIA) to inform reimbursement decisions on health technologies. Evidence from the Netherlands suggests that CEA requirements are consistent between the different stages of the decision-making process in the Netherlands, while BIA requirements are not. It remains unclear why aspects of BIAs vary in form and importance across decision stages, and why BIA results do not have a clear and consistent relationship with CEA results. Therefore, this study aimed to obtain further insight into the role of budget impact in the different stages of the decision-making process in the Netherlands, and into the experiences of decision-makers that may explain the variation in use of BIA across these stages. To meet this aim, we conducted semi-structured interviews with 12 decision-makers and 3 pharmaceutical industry representatives. Our findings indicate that BIAs serve multiple purposes depending on the responsibilities and needs of decision-makers in a specific decision stage. Each purpose may be relatively well-defined, and decision-makers seemingly have a clear understanding of the evidence on (aspects of) budget impact required for achieving their specific purpose. For example, the selection of pharmaceuticals for assessment is based on the maximum financial risk associated with reimbursement, discarding evidence on savings and substitution effects in other budgets and sectors, while these broader healthcare and societal elements are included during the appraisal stage. Hence, a clear framework for the consistent use of evidence on budget impact across decision stages has not yet been established.