Priority setting, also known as rationing or resource allocation, is a complex and difficult problem faced by all decision makers at all levels of all health systems, including macro (e.g. governments), meso (e.g. regional health authorities (RHAs), hospitals), and micro (e.g. clinical programs) levels. There is relatively little interaction between decision makers at the three levels, or among institutions, regarding the setting of priorities. Consequently, priority setting has been described as a series of unconnected experiments with no systematic mechanism for capturing the lessons, or evaluating the strengths and weaknesses, of each experiment . Hospital administrators, constrained by budget restrictions and confronted by increasing demand, find it a particularly difficult challenge to maintain services and quality, while controlling costs; decision makers (or leaders) lack guidance and information for priority setting and are unaware of priority setting tools available to them [2–4]. Mitton and Donaldson found decision makers were "frustrated with the lack of an explicit priority setting framework" and questioned "the credibility of resource allocation decision-making" (p. 1660). Several studies have reported that leaders desire an explicit framework to guide priority setting [4–6] and acknowledged leadership as a key area where improvement can make the most difference .
The sustainability of healthcare systems worldwide is threatened by a growing demand for services and expensive innovative technologies. Decision makers struggle in this environment to set priorities appropriately, particularly because they lack consensus about which values should guide their decisions . One way to approach this problem is to determine what relevant stakeholders understand successful priority setting to mean. Greater insight into stakeholders' attitudes and perceptions of achieving successful priority setting could improve the way in which institutions and healthcare organizations set priorities.
Successful priority setting is a desirable goal for decision makers; however there is no agreed upon definition for successful priority setting, so there is no way of knowing if an organization achieves it. Priority setting is extremely complex – choosing between competing values makes priority setting fundamentally an ethical issue . Different disciplines offer their own perspective on how priority setting 'ought' to be done, defining 'good' (or successful) priority setting through values such as efficiency, equity, or justice. Discipline specific approaches and priority setting frameworks can help decision makers with priority setting: health economics encourages a focus on efficiency, policy approaches focus on legitimacy, evidence-based medicine looks to effectiveness. Daniels and Sabin created 'accountability for reasonableness' (A4R) with legitimacy and fairness as two key goals of priority setting . Interdisciplinary approaches are also available such as program-budgeting and marginal analysis (PBMA), health technology assessment (HTA). Menon et al. described priority setting in four steps: (1) identification of health care needs, (2) allocation of resources, (3) communication of decisions to stakeholders, and (4) management of feedback from them . Still, there is no consensus that any one framework provides the 'correct' or 'best' comprehensive definition of successful priority setting.
These normative approaches are necessary because they help identify important values and underlying assumptions in priority setting, however alone they are insufficient and provide only a piece of a definition of successful priority setting. The problem that remains is: priority setting involves the adjudication between many relevant values and that people (and disciplines) will disagree about which values should dominate in any specific priority setting context and there is no agreed upon normative approach for resolving the disagreement. When relevant values conflict, decision makers must rely on developing context-specific agreement in order to achieve priority setting success.
Empirical studies are also important for understanding current decision making practices within healthcare organizations [14, 15]; since they identify current priority setting practices, they provide insight into defining successful priority setting. In recent years, there have been empirical descriptions of priority setting in various contexts (e.g. waitlists [16–18], hospitals [19–21], and RHAs [13, 22]). Other empirical studies have evaluated actual priority setting against an ethical framework (e.g. [19, 23]). Studies have been done detailing factors that influence priority setting practices, including technical factors (such as clinical practice guidelines), non-technical factors (such as alignment with goals)  and clusters of factors . Several studies have brought forth components for improving priority setting or ensuring success in priority setting, such as stakeholder engagement  increased dialogue , a culture supporting explicit priority setting , decision maker/group composition (size and representation) , clear information management and clarity of process , and local ownership and awareness of local politics .
Only a few studies have presented ideas for evaluating the success of priority setting including: economic evaluations [27, 28], checklists looking at both pragmatic (such as establish organizational objectives and ensure implementation) and ethical considerations (such as publicity and appeals), success parameters (effect on organizational priorities and budgets, effect of staff, and effect on community, efficiency of priority setting process, fairness, conformity with conditions of accountability for reasonableness), a criteria-based framework (including objectives and context, methodology, process issues, and study outcomes), outputs-based measures (such as usefulness re-allocation, improved patient outcomes) , and a model for ethical standards (including health of patients, professional (clinical) expertise, public health, unmet health needs, advocacy for social policy reform, relationships of special ethical importance (with employees), organizational solvency/survival, and benefit to community) . Together, these studies contribute to our understanding of successful priority setting; but on their own, do not provide a comprehensive definition.
Evaluating success of health care (and other sectors) is possible through many of the aforementioned tools/processes, and different instruments may elicit different results . The problem with these studies is their limited focus (narrow organizational study and/or small range of stakeholders). While we are more cognizant of important factors in successful priority setting, we still do not have a complete picture of it.
Normative approaches tell us what ought to be done, empirical studies tell us what is being done, and we are still left with a lack of consensus on an appropriate approach to successful priority setting. There is a need to define successful priority setting, to provide a common language, and to come to some agreement on conceptual basis for the concept.
A first step to ground such a definition is to collect and synthesize the views of stakeholders with direct priority setting knowledge and experience. Stakeholders include decision makers (particularly in publicly funded health systems, who are under growing pressure to base their decisions on available evidence and to demonstrate the effectiveness of their decision), patients (since the health system exists for them and because they fund the health system through taxes, insurance premiums or out-of-pocket payments), and priority setting scholars (who can provide different theoretical viewpoints on decision making). Creating a framework that defines success in priority setting is a necessary step toward improving priority setting practices in healthcare organizations [34, 35].
The purpose of this paper is to present a synthesized definition of successful priority setting brought together from the findings of three empirical studies describing successful priority setting from the viewpoint of stakeholders (decision makers, patients, and priority setting scholars). The definition is presented as a conceptual framework with ten elements. The framework we describe here is a new development for evaluating priority setting; it can provide guidance to decision makers and scholars interested in successful priority setting.