An epistemology of patient safety research: a framework for study design and interpretation. Part 1. Conceptualising and developing interventions C Brown, 1 T Hofer, 2 A Johal, 1 R Thomson, 3,4 J Nicholl, 5 B D Franklin, 6 R J Lilford 1 See Editorial, p 154 1 Department of Public Health and Epidemiology, University of Birmingham, Birmingham, UK; 2 University of Michigan Medical School, Ann Arbor, Michigan, USA; 3 National Patient Safety Agency, London, UK; 4 Newcastle upon Tyne Medical School, Newcastle upon Tyne, UK; 5 University of Sheffield, Sheffield, UK; 6 London School of Pharmacy, London, UK Correspondence to: Dr C Brown, Research Methodology Programme, Department of Public Health and Epidemiology, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; c.a.brown@bham.ac.uk Accepted 18 January 2008 ABSTRACT This is the first of a four-part series of articles examining the epistemology of patient safety research. Parts 2 and 3 will describe different study designs and methods of measuring outcomes in the evaluation of patient safety interventions, before Part 4 suggests that ‘‘one size does not fit all’’. Part 1 sets the scene by defining patient safety research as a challenging form of service delivery and organisational research that has to deal (although not exclusively) with some very rare events. It then considers two inter-related ideas: a causal chain that can be used to identify where in an organisation’s structure and/or processes an intervention may impact; and the need for preimplementation evaluation of proposed interventions. Finally, the paper outlines the authors’ pragmatist ontological stance to patient safety research, which sets the philosophical basis for the remaining three articles. We have documented a massive rise in patient safety research over the past decade. 1 Much of this consists of basic research in cognate disciplines such as psychology, sociology, organisational stu- dies, ergonomics and education. Improving patient safety requires that the knowledge gleaned from basic science and clinical research should be taken up in the design of interventions to improve patient care. This is the first of four articles dealing with the development and evaluation of such interventions. In these articles we summarise the results of a report to the Medical Research Council (MRC) ‘‘The epistemology of patient safety research: a framework for study design and interpretation’’. 2 In this first article we set the scene. We first describe the causal chain through which interventions designed to reduce the num- ber of patient safety incidents impact on complex systems such as healthcare organisations. Second, we discuss the process through which interven- tions should be selected and refined even before they are rolled out in practice: preimplementation evaluation. Last, we describe and briefly defend the philosophical (ontological and epistemological) premises to which we subscribe and on which the arguments in subsequent articles will build. Part 2 of this series will consider the different types of study design that could be used when interventions are evaluated in healthcare organisa- tions and will show that the different methods have strengths and weaknesses that vary according to the type of intervention being evaluated: one size does not fit all. In Part 3 we will discuss how quality and safety may be measured, with parti- cular reference to potential biases. In Part 4 we will bring the various themes together and show how many different sources of knowledge, including the results of preimplementation evaluations and data arising from different points in the causal chain, can be integrated in a bayesian statistical frame- work. OUR POINT OF DEPARTURE: THE NATURE OF PATIENT SAFETY INTERVENTIONS Safer care can sometimes be achieved by replacing unsafe treatments and technologies (such as medical devices or surgical techniques) with safer alternatives and the study of these alternatives is often referred to as health technology assessment (HTA). Healthcare can also be made safer by more appropriate use of existing treatments—that is, improvements in the system in which patient care is embedded. The study of methods to strengthen the system is often considered to fall within service delivery and organisational (SDO) research or health services research. Since the patient safety movement is usually conceptualised in terms of seeking to improve the systems within which staff work, 3 most patient safety research would seem to fit under the broad heading of SDO research. 4 For all that it might be part of SDO research, safety research does have one idiosyncrasy with strong methodological implications: the extreme rarity of many of the events that safety interventions aim to reduce. THE SAFETY/QUALITY CONTINUUM AND THE RARITY OF SAFETY EVENTS The safety incidents that make the news usually involve dramatic events such as wrong site surgery, lethal dose miscalculations, deaths following inad- vertent intravenous potassium chloride concen- trate and inadvertent intrathecal administration of vincristine. As well as leading to severe harm, the link between error and the adverse outcome in these high-profile cases is: c immediate (or rapid); c certain (or highly likely). For these reasons, such errors are sometimes given the sobriquet ‘‘egregious’’: the fact that an error has produced the poor outcome is indispu- table. These errors also have a third feature in common: c they are all very rare—in some cases a country the size of the UK may experience fewer than one case per year. Not all safety incidents make the news: those that do not tend to be those with lower immediacy and causality, but which occur more frequently. Developing research and practice 158 Qual Saf Health Care 2008;17:158–162. doi:10.1136/qshc.2007.023630 group.bmj.com on February 11, 2016 - Published by http://qualitysafety.bmj.com/ Downloaded from