Many policy makers, researchers, public health specialists and other stakeholders in the European Union (EU) have expressed interest in better understanding the performance of their health systems to identify opportunities for improvement in effectiveness, efficiency and equity. At the same time, health system performance assessment (HSPA) at EU level has received considerable attention as an instrument to improve transparency and accountability.
According to Smith [1, 2] the prime objectives of HSPA are:
to set out the goals and priorities for a health system;
to act as a focus for policymaking and coordinating actions within the health system;
to measure progress towards achievement of goals;
to act as a basis for comparison with other health systems;
to promote transparency and accountability to citizens and other legitimate stakeholders for the way that money has been spent.
While policy making in many areas of EU health systems is in the responsibility of Member States (MSs), cross-country comparisons of health system performance have become increasingly important. First, structural reform in many MSs and policy recommendations from the European Commission have been increasingly targeting health care. A large and growing share (30% in 2013) of social protection spending in the EU is used for health care services . Second, the crisis including recent migrant waves led to increased pressure on various segments of social spending including health. Sustainability and efficiency of health spending is thus high on the agenda. The development of the directive aimed at making cross-border health care for the EU citizens possible is seen as another major driver behind the increased use of comparisons and benchmarking of quality of care provided [2, 4]. Also, the growing availability of comparable datasets has enhanced the technical feasibility to compare performance . These data, carefully analysed and accompanied by conceptual models of knowledge are powerful tools to influence policy-making [2, 5]. Finally, providing expertise and assistance in the area of HSPA are a fundamental role for the EU level, in setting standards, collating and disseminating experience, and disseminating standardised information. Such endeavours are a public good that can only be done effectively and comprehensively at EU level, and can contribute new resources for guiding policy and practice in individual MSs.
Health system performance is measured against multiple objectives. This calls for a strong framework covering access, equity, efficiency and quality and their interrelation in order to understand the content and the scope of the comparison [2, 6]. Although HSPA is primarily a country-specific process for which there is no single accepted template, having harmonised methodologies and tools to support health policy makers in taking decisions requires actions also at EU level [1, 7]. The importance of good practice HSPA therefore has been receiving high-level support both at national and at EU level [7, 8]. The European Commission (EC) communication on effective, accessible and resilient health systems  and the mandate from November 2014 given to the European Commissioner for Health by the EC President to develop expertise for HSPA provide evidence of this support .
Progress has been made in monitoring the health of the population and the performance of health systems in terms of the scope, nature and timeliness of performance data that have been made publicly available over the last 30 years . Nevertheless, methodological challenges remain in accomplishing the aim of health system governance improvement. These challenges include creating and unifying reporting standards of data and indicators, and establishing coherent HSPA frameworks for cross-country comparisons . This should ultimately guide the way how best to deploy performance data . The wider performance framework developed under the EuroREACH project based on the OECD HCQI initiative may be seen as one of the starting points in this context .
Clear evidence is needed on the prioritization, including the necessity and rationale for specific health system indicators. Furthermore, core indicators for different types of policy-use, (e.g. monitoring/forecasting, benchmarking, target-setting, cross-country comparison) should be identified and categorised accordingly. In recent years, some advanced cross-country approaches were established analysing the comparative performance of disease specific variables across countries (EuroHOPE)  as well as regional variations of hospital indicators (ECHO) . However, there is a lack of a European-wide coherent framework addressing data needs, quality of data and guidance in using and applying indicators of HSPA.
While the Euro Health Consumer Index (EHCI), a private initiative ranking 35 European health systems according to their performance along 38 indicators shed light on the potential of comparing important health and health system indicators , it has been criticised by some for the lack of transparency in indicator selection and scoring . More work is needed in providing standards for the quality of indicators and for a sound rational of monitoring specific indicators and their significance in cross-country comparisons. These challenges are being addressed in BRIDGE Health, a European project that aims at preparing a comprehensive, integrated and sustainable EU health information system which will incorporate know-how and technical tools to coordinate and harmonise research and surveillance for MSs in key EU health policy areas . The present work forms an integral part of BRIDGE Health research activities. In addition, the BRIDGE Health System Indicator Task Force was established to exchange expertise on the work of health system performance indicators development.
Currently, stakeholders have difficulty navigating the HSPA landscape, understanding the opportunities and tools it provides, and using the data to identify opportunities for improvement in effectiveness, efficiency and equity of their healthcare systems. To the best of our knowledge, no synthesis exists to help understand the organization of the HSPA system at the EU level. Hence, the goal of this paper is to synthesise the current state and developments in the field of HSPA relevant to the EU context by visually mapping the relationships between the different actions and actors involved in HSPA in the EU.
The rest of the paper is organised as follows. The second part presents the methods, including six predefined selection criteria of initiatives and the output classification that led to the structure of the visual map. Section 3 describes the different initiatives that were identified both at EU and joint action levels. Finally, the implications of the current structure of HSPA in the EU are discussed.