An international language for patient safety: Global progress in patient safety requires classification of key concepts.

The past 10 years has seen a rapid growth in research and action on patient safety throughout the world [1]. This is a welcome development. However, comparative analysis of risks to patient safety has been constrained by the absence of a common, internationally agreed set of patient safety concepts. In fact, patient safety appears to be a field of scientific endeavour in which identical terms are often understood to mean quite different things, depending on the standpoint of individuals involved. Such ambiguity frustrates progress.

Since its inception in 2004, the WHO World Alliance for Patient Safety has recognized the importance of addressing this problem [2]. Over the past 3 years, careful, comprehensive work involving a wide range of experts from across the world has focussed on identifying and agreeing upon safety-related concepts, definitions and preferred terms based on solid theoretical and analytical foundations [3]. This has led to the development of a conceptual framework for an International Classification for Patient Safety (ICPS). Despite its many complexities, the central goal has been clear throughout—to enable categorization of patient safety information into a standardized set of concepts with agreed definitions and preferred terms.

The importance of being able to classify more consistently the major concepts associated with patient safety cannot be under-estimated. The ICPS is not simply part of the semantics of patient safety. Illnesses and drugs, for example, are classified in order to aid diagnosis and help patients recover from their disease. Patient safety is no different. Classification is the means to better understand and communicate about hazards, common sources of risk and strategies to improve patient safety. The consistent use of key patient safety concepts with agreed definitions and preferred terms, in conjunction with a comprehensive but adaptable classification, paves the way for the systematic collection, aggregation and analysis of relevant information. In short, classification must be deeply integrated in all work on patient safety around the world.

The World Alliance for Patient Safety has had a particular interest in reaching a wide range of interested audiences and potential users of the ICPS. This not only includes developers and managers of safety-reporting systems, but also the researchers, policy makers and patient groups who will use this information to better understand risks to patients to develop strategies to improve patient safety.

The three companion papers published in this issue of the journal mark an important step in bringing the future direction of the programme of work to develop the ICPS to a wider audience. Each paper outlines a different aspect of the work that has been undertaken to date. The first paper by Sherman et al. provides an overview of the initiative including the formation of a Drafting Group and the development of guiding principles The second paper, by Thomson et al., describes how a web-based two-phase modified Delphi process ensured substantial input from interested parties throughout the world and informed the development of an agreed conceptual framework and related concepts The third paper by Runciman et al. describes in more detail the resulting definitions and preferred terms for the 48 key concepts and how they relate to each other.

Much remains to be done. Patient safety is a relatively new and emerging area of scientific discovery. A pragmatic and dynamic view must be taken of the ongoing development of the ICPS so as to incorporate new insights and knowledge. The ultimate vision is simple and consistent. The ICPS will be a solid foundation for global efforts to ensure rapid and systematic learning from the experiences of patient harm to make care safer for future patients everywhere.