Despite its phenomenal success since its inception in the early nineteen-nineties, the evidence-based medicine movement has not succeeded in shaking off an epistemological critique derived from the experiential or tacit dimensions of clinical reasoning about particular individuals. This critique claims that the evidence-based medicine model does not take account of tacit knowing as developed by the philosopher Michael Polanyi. However, the epistemology of evidence-based medicine is premised on the elimination of the tacit dimension from clinical judgment. This is demonstrated through (...) analyzing the dichotomy between clinical and statistical intuition in evidence-based medicine’s epistemology of clinical reasoning. I argue that clinical epidemiology presents a more nuanced epistemological model for the application of statistical epidemiology to the clinical context. Polanyi’s theory of tacit knowing is compatible with the model of clinical reasoning associated with clinical epidemiology, but not evidence-based medicine. (shrink)

Robert Truog describes the controversial randomized controlled trials (RCTs) of extracorporeal membrane oxygenation (ECMO) therapy in newborns. Because early results with ECMO indicated that it might be a great advance, saving many lives, Truog argues that ECMO should not have been tested using RCTs, but that a long-term, large-scale observational study of actual clinical practice should have been conducted instead. Central to Truog’s argument, however, is the idea that ECMO is an unusual case. Thus, it is an open question whether (...) Truog’s conclusions can be extended to other areas of medical research. In this paper, I look at epistemological and ethical issues arising in the care of patients with chronic diseases, using ECMO as a starting point. Both the similarities and the dissimilarities of these two cases highlight important issues in biomedical research and support a conclusion similar to Truog’s. Observational studies of clinical practice provide the best evidence to inform the treatment of patients with chronic disease. (shrink)

The Evidence-Based Medicine (EBM) movement is an ideological force in health research and health policy which asks for allegiance to two types of methodological doctrine. The first is the highly quotable motherhood statement: for example, that we should make conscientious, explicit and judicious use of current best evidence (paraphrasing Sackett). The second type of doctrine, vastly more specific and in practice more important, is the detailed methodology of design and analysis of experiments. This type of detailed methodological doctrine tends to (...) be simplified by commentators but followed to the letter by practitioners. A number of interestingly dumb claims have become entrenched in prominent versions of these more specific methodological doctrines. I look at just a couple of example claims, namely: Any randomised controlled trial (RCT) gives us better evidence than any other study. Confidence intervals are always useful summaries of at least part of the evidence an experiment gives us about a hypothesis. To offer a positive doctrine which might move us past the current conflict of micro-theories of evidence, I propose a mild methodological pluralism: in any local context in which none of a variety of scientific methodologies is clearly and uncontentiously right, researchers should not be discouraged from using any methodology for which they can provide a good argument. (shrink)

Evidence-based medicine has been studied as a rich and diverse set of epistemic and infrastructural practices that relate imperfect medical knowledges to complex clinical practices. We examine instances of medical decision-making where medical professionals relate recommendations from clinical practice guidelines to individual patient characteristics when deciding to prescribe implantable cardioverter defibrillators to treat heart failure. When connecting evidence-based recommendations to decisions about individual patients, we find that clinical deliberations invoke different times, such as linear, chronological time, and biological aging, as (...) well as different futures, such as individual future risks and the future sustainability of health systems. Such different “temporalities of evidence” are integral parts of clinicians’ considerations concerning economy, suffering, risks, and hopes in making decisions on individual patients. In line with calls to anchor science and technology studies scholarship studying EBM in the concerns that matter most to patients and health care providers, we argue that the social study of EBM needs to attend to such temporalities to understand how evidence is weighed, which outcomes are considered important, and hence which clinical action is proposed. However, since different ways of “doing time” lead to different appreciations of the clinical outcomes, the notion of clinical “anchoring” becomes rather elusive. (shrink)

Sociologists of science have argued that due to the institutional reward system negative research results, such as failed experiments, may harm scientific careers. We know little, however, of how scientists themselves make sense of negative research findings. Drawing from the sociology of work, the author discusses how researchers involved in a double-blind, placebo, controlled randomized clinical trial for methamphetamine dependency informally and formally interpret the emerging research results. Because the drug tested in the trial was not an effective treatment, the (...) staff considered the trial a failure. In spite of the disappointing results, the staff involved in the daily work with research subjects still reframed the trial as meaningful because they were able to treat people for their drug dependency. The authors of the major publication also framed the results as worthwhile by linking their study to a previously published study in a post hoc analysis. The author concludes that negative research findings offer a collective opportunity to define what scientific work is about and that the effects of failed experiments depend on individual biography and institutional context. (shrink)

The ideology of evidence-base medicine (EBM) has dramatically altered the way we think, conceptualize, philosophize and practice medicine. One of its major pillars is the appraisal and classification of evidence. Although important and beneficial, this process currently lacks detail and is in need of reform. In particular, it largely focuses on three key dimensions (design, [type I] alpha error and beta [type II] error) to grade the quality of evidence and often omits other crucial aspects of evidence such as biological (...) plausibility, reproducibility, generalizability, temporality, consistency and coherence. It also over-values the randomized trial and meta-analytical techniques, discounts the biasing effect of single centre execution and gives insufficient weight to large and detailed observational studies. Unless these aspects are progressively included into systems for grading, evaluating and classifying evidence and duly empirically assessed (according to the EBM paradigm), the EBM process and movement will remain open to criticism of being more evidence-biased than evidence-based. (shrink)

This paper explores some of the important parallels between recent reforms to legal rules for the admissibility of scientific and expert evidence, exemplified by the US Supreme Court's decision in Daubert v Merrell Dow Pharmaceuticals, Inc. in 1993, and similar calls for reforms to medical practice, that emerged around the same time as part of the Evidence-Based Medicine (EBM) movement. Similarities between the “movements” can be observed in that both emerged from a historical context where the quality of medicine and (...) legal approaches to science were being subjected to growing criticism, and in the ways that proponents of both movements have used appeals to “folk epistemologies” of science to help legitimate their reform aspirations. The term folk epistemology is used to describe the weaving together of formal and informal images of scientific method with normative and pragmatic concerns such as eradicating “junk science”, and promoting medical best practice. Perhaps unsurprisingly, given the unfocused breadth of these aspirations the implications of these “reforms” for medical and legal practice have not been straightforward, although they do represent an important new set of rhetorical resources to critique and or legitimate expertise in medical and legal domains. Discussion closes, by noting the growth of calls for these movements to reciprocate in areas where law and medicine intersect, such as medical negligence litigation. (shrink)

Gender affirming hormone treatment is an important part of the care of trans adolescents which enables them to develop the secondary sexual characteristics congruent with their identified genders. There is an increasing amount of empirical evidence showing the benefits of gender affirming hormone treatment for psychological health and social well-being in this population. However, in several countries, access to gender affirming hormone treatment for trans adolescents has recently been severely restricted. While much of the opposition to gender affirming hormone treatment (...) for trans adolescents has in part been ideologically motivated, it also reflects a debate about whether there are harms that outweigh the benefits of the treatment. Accordingly, a systematic and comprehensive philosophical analysis of the ethics of gender affirming hormone treatment for trans adolescents is needed. Herein, I offer such an analysis that draws on the four principles of biomedical ethics by Tom Beauchamp and James Childress. Based on the considerations of beneficence, nonmaleficence, autonomy, and justice, I argue that the provision of access to gender affirming hormone treatment for consenting trans adolescents is ethically required and that the current restrictions to such treatment are ethically wrong. (shrink)

Evidence-based medicine (EBM) puts forward a hierarchy of evidence for informing therapeutic decisions. An unambiguous interpretation of how to apply EBM's hierarchy has not been provided in the clinical literature. However, as much as an interpretation is provided proponents suggest a categorical interpretation. The categorical interpretation holds that all the results of randomised trials always trump evidence from lower down the hierarchy when it comes to informing therapeutic decisions. Most of the critical replies to EBM react to this interpretation. While (...) proponents of EBM can avoid some of the problems raised by critics by suitably limited the claims made on behalf of the hierarchy, further problems arise. If EBM is to inform therapeutic decisions then a considerably more restricted, and context dependent interpretation of EBM's hierarchy is needed. (shrink)

Proponents of evidence-based medicine (EBM) provide the “hierarchy of evidence” as a criterion for judging the reliability of therapeutic decisions. EBM's hierarchy places randomized interventional studies (and systematic reviews of such studies) higher in the hierarchy than observational studies, unsystematic clinical experience, and basic science. Recent philosophical work has questioned whether EBM's special emphasis on evidence from randomized interventional studies can be justified. Following the critical literature, and in particular the work of John Worrall, I agree that many of the (...) arguments put forward by advocates of EBM do not justify the ambitious claims that are often made on behalf of randomization. However, in contrast to the recent philosophical work, I argue that a justification for EBM's hierarchy of evidence can be provided. The hierarchy should be viewed as a hierarchy of comparative internal validity. Although this justification is defensible, the claims that EBM's hierarchy substantiates when viewed in this way are considerably more circumscribed than some claims found in the EBM literature. (shrink)

Evidence-based policy has support in many areas of government and in public affairs more generally. In this paper we outline what evidence-based policy is, then we discuss its strengths and weaknesses. In particular, we argue that it faces a serious challenge to provide a plausible, over-arching account of evidence. We contrast evidence-based policy with evidence-based medicine, especially the role of evidence in assessing the effectiveness of medicines. The evidence required for policy decisions does not easily lend itself to randomized controlled (...) trials, nor, for that matter, being listed in a single all-purpose hierarchy. (shrink)

Evidence-Based Medicine (EBM) has now been part of the dominant medical paradigm for 15 years, and has been frequently debated and progressively modified. One question about EBM that has not yet been considered systematically, and is now particularly timely, is the question of the novelty, or otherwise, of the principles and practices of EBM. We argue that answering this question, and the related question of whether EBM-type principles and practices are unique to medicine, sheds new light on EBM and has (...) practical implications for those involved in all EBM. This is because one's answer to the question (whether explicit or implicit) affects the amount and type of funding and attention received by EBM, the extent to which EBM, and the generation, judgment and use of evidence more generally, can be appropriated by certain groups and questioned by others, and the extent to which truly unique socio-political developments in evidence, and in medicine more generally, are recognized and harnessed. (shrink)

Evidence hierarchies are lists of investigative strategies ordered with regard to the claimed strength of evidence. They have been used for a couple of decades within EBM, particularly for the assessment of evidence for treatment recommendations, but they remain controversial. An under-investigated question, from critics and adherents of evidence hierarchies alike, is what the order in the hierarchy means. Four interpretations of the order are distinguished and discussed. The two most credible ones are, roughly expressed, "typically stronger" or "ideally stronger". (...) The well-known GRADE framework seems to assume some "typically stronger" reading. Unfortunately, even if the interpretation of an evidence hierarchy were established, hierarchies appear to be rather unhelpful for the task of evidence aggregation. Nevertheless, a specification of the intended order relation may be helpful in sorting out disagreements in debates on evidence hierarchies. Therefore, proponents and adversaries of evidence hierarchies are equally obliged to specify the order interpretations they are assuming in their arguments. (shrink)

Several have argued that the aims of scientific research are not always independent of social and ethical values. Yet this is often assumed only to have implications for decisions about what is studied, or which research projects are funded, and not for methodological decisions or standards of evidence. Using the case of the recently developed HPV vaccines, we argue that the social aims of research can also play important roles in justifying decisions about (1) how research problems are defined in (...) drug development, (2) evidentiary standards used in testing drug “success”, and (3) clinical trial methodology. As a result, attending to the social aims at stake in particular research contexts will produce more rational methodological decisions as well as more socially relevant science. (shrink)

Evidence-based psychiatry (EBP) has arisen through the application of evidence-based medicine (EBM) to psychiatry. However, there may be aspects of psychiatric disorders and treatments that do not conform well to the assumptions of EBM. This paper reviews the ongoing debate about evidence-based psychiatry and investigates the applicability, to psychiatry, of two basic methodological features of EBM: prognostic homogeneity of clinical trial groups and quantification of trial outcomes. This paper argues that EBM may not be the best way to pursue psychiatric (...) knowledge given the particular features of psychiatric disorders and their treatments. As a result, psychiatry may have to develop its own standards for rigour and validity. This paper concludes that EBM has had a powerful influence on how psychiatry investigates and understands mental disorders. Psychiatry could influence EBM in return, reshaping it in ways that are more clinically useful and congruent with patients’ needs. (shrink)

As the quality movement in health care now enters its fourth decade, the language of quality is ubiquitous. Practitioners, organizations, and government agencies alike vociferously testify their commitments to quality and accept numerous forms of governance aimed at improving quality of care. Remarkably, the powerful phrase ‘‘quality of care’’ is rarely defined in the health care literature. Instead it operates as an accepted and assumed goal worth pursuing. The status of evidence-based medicine, for instance, hinges on its ability to improve (...) quality of care, and efforts are made by both proponents and detractors to unpack the contents and outcomes of evidence-based practice while the contents of ‘‘quality of care’’ are presumed to be understood. Because the goals of medicine are far from obvious, this paper investigates the neglected term, ‘‘quality of care,’’ in an effort to understand what it is that health care practices are so uncritically assumed to be striving for. Finding lack of consensus on the terminology in the quality literature, I propose that the term operates rhetorically by way of persuasive appeal (and lack of descriptive meaning). Unsatisfied that ‘‘quality of care’’ operates as a mere buzzword in morally contentious debates over resource allocation and duties of care, I implore health care communities to go beyond mere commitments to quality and, instead, to focus attention on the difficult task of specifying what counts as quality care within an economically constrained health care system. (shrink)

Evidence-based policy is gaining support in many areas of government and in public affairs more generally. In this paper we outline what evidence—based policy is then discuss its strengths and weaknesses. In particular, we argue that it faces a serious challenge to provide a plausible account of evidence. This account needs to be at least in the spirit of the hierarchy of evidence subscribed to by evidence-based medicine (from which evidence—based policy derives its name and inspiration). Yet evidence-based policy’s hierarchy (...) needs to be tailored to the kinds of evidence relevant and available to the policy arena. The evidence required for policy decisions does not easily lend itself to randomised controlled trials (the "gold standard" in evidence-based medicine), nor, for that matter, being listed in a single all—purpose hierarchy. (shrink)

The thesis consists of an introduction and two papers. In the introduction a brief historical survey of empirical investigations into the effectiveness of medicinal interventions is given. Also, the main ideas of the EBM movement are presented. Both included papers can be viewed as investigations into the reasonableness of EBM and its hierarchies of evidence. Paper I: Typically, in a clinical trial patients with specified symptoms are given either of two or more predetermined treatments. Health endpoints in these groups are (...) then compared using statistical methods. Concerns have been raised, not least from adherents of so-called alternative medicine, that clinical trials do not offer reliable evidence for some types of treatment, in particular for highly individualized treatments, for example traditional homeopathy. It is argued that such concerns are unfounded. There are two minimal conditions related to the nature of the treatments that must be fulfilled for evaluability in a clinical trial, namely the proper distinction of the two treatment groups and the elimination of confounding variables or variations. These are delineated, and a few misunderstandings are corrected. It is concluded that the conditions do not preclude the testing of alternative medicine, whether individualized or not. Paper II: Traditionally, mechanistic reasoning has been assigned a negligible role in standard EBM literature, although some recent authors have argued for an upgrading. Even so, mechanistic reasoning that has received attention has almost exclusively been positive -- both in an epistemic sense of claiming that there is a mechanistic chain and in a health-related sense of there being claimed benefits for the patient. Negative mechanistic reasoning has been neglected, both in the epistemic and in the health-related sense. I distinguish three main types of negative mechanistic reasoning and subsume them under a new definition of mechanistic reasoning in the context of assessing medical interventions. Although this definition is wider than a previous suggestion in the literature, there are still other instances of reasoning that concern mechanisms but do not count as mechanistic reasoning. One of the three distinguished types, which is negative only in the health-related sense, has a corresponding positive counterpart, whereas the other two, which are epistemically negative, do not have such counterparts, at least not that are particularly interesting as evidence. Accounting for negative mechanistic reasoning in EBM is therefore partly different from accounting for positive mechanistic reasoning. Each negative type corresponds to a range of evidential strengths, and it is argued that there are differences with respect to the typical strengths. The variety of negative mechanistic reasoning should be acknowledged in EBM, and presents a serious challenge to proponents of so-called medical hierarchies of evidence. (shrink)

The thesis consists of an introduction and five papers. The introduction gives a brief historical survey of empirical investigations into the effectiveness of medicinal interventions, as well as surveys of the concept of evidence and of the history and philosophy of experiments. The main ideas of the EBM movement are also presented. Paper I: Concerns have been raised that clinical trials do not offer reliable evidence for some types of treatment, in particular for highly individualised treatments, for example traditional homeopathy. (...) With respect to individualised treatments, it is argued that such concerns are unfounded. There are two minimal conditions related to the nature of the treatments that must be fulfilled for evaluability in a clinical trial, namely the proper distinction of treatment groups and the elimination of confounding variables or variations. These conditions do not preclude the testing of individualised medicine. Paper II: Traditionally, mechanistic reasoning has been assigned a negligible role in the EBM literature. When discussed, mechanistic reasoning has almost exclusively been positive – both in an epistemic sense of claiming that there is a mechanistic chain and in a health-related sense of there being claimed benefits for the patient. Negative mechanistic reasoning has been neglected. I distinguish three main types of negative mechanistic reasoning and subsume them under a new definition. One of the three distinguished types, which is negative only in the health-related sense, has a corresponding positive counterpart, whereas the other two, which are epistemically negative, do not have such counterparts, at least not that are particularly interesting as evidence. Accounting for negative mechanistic reasoning in EBM is therefore partly different from accounting for positive mechanistic reasoning. Paper III: Evidence hierarchies are lists of investigative strategies ordered with regard to the claimed strength of evidence. They have been used for a couple of decades within EBM, particularly for the assessment of evidence for treatment recommendations, but they remain controversial. An under-investigated question is what the order in the hierarchy means. Four interpretations of the order are distinguished and discussed. The two most credible ones are, in rough terms, “typically stronger” and “ideally stronger”. The GRADE framework seems to be based on the “typically stronger” reading. Even if the interpretation of an evidence hierarchy were established, hierarchies appear to be rather unhelpful for the task of evidence aggregation. However, specifying the intended order relation may help sort out disagreements. Paper IV: There are three main arguments for randomisation that connect inseparably to theoretical concepts: Randomisation is useful for performing null hypothesis testing. Randomisation is needed for plausible causal inferences from treatment to effect. Randomisation is acceptable and computationally convenient in a Bayesian setting. A critical scrutiny of these arguments shows that is acceptable in the context of clinical trials. As for, it is argued that randomisation only provides weak reasons for drawing causal inferences in the context of real clinical trials. Argument is weak because it is controversial among Bayesians, and because formally Bayesian analyses of trial results are rarely asked for. Paper V: Practical arguments for randomisation are arguments with no necessary connections to theoretical frameworks like null hypothesis testing or causal inferences. Four common practical arguments in the context of clinical trials are distinguished and assessed: Randomisation contributes to allocation concealment. Randomisation contributes to the baseline balance of treatment groups. Randomisation decreases self-selection bias. Randomisation removes allocation bias. Argument is rejected. Arguments and are approved. Argument is rejected if it is formulated so as to be independent from and, but it is true that randomisation contributes to balance through the mechanisms mentioned in and. It is judged that may be the strongest single argument. (shrink)

Hierarchies of evidence are an important and influential tool for appraising evidence in medicine. In recent years, hierarchies have been formally adopted by organizations including the Cochrane Collaboration [1], NICE [2,3], the WHO [4], the US Preventive Services Task Force [5], and the Australian NHMRC [6,7]. The development of such hierarchies has been regarded as a central part of Evidence-Based Medicine, a movement within healthcare which prioritises the use of epidemiological evidence such as that provided by Randomised Controlled Trials. Philosophical (...) work on the methodology of medicine has so far mostly focused on claims about the superiority of RCTs, and hence has largely neglected the questions of what hierarchies are, what assumptions they require, and how they affect clinical practice. This thesis shows that there is great variation in the hierarchies defended and in the interpretations they are, and can be, given. The interpretative assumptions made in using hierarchies are crucial to the content and defensibility of the underlying philosophical commitments concerning evidence and medical practice. Once this variation is been identified, it becomes clear that the little philosophical work that has been done so far affects only some hierarchies, under some interpretations. Modest interpretations offered by La Caze [11], conditional hierarchies like GRADE [12-14], and heuristic approaches such as that defended by Howick et al. [15,16] all survive previous philosophical criticism. This thesis extends previous criticisms by arguing that modest interpretations are so weak as to be unhelpful for clinical practice; that GRADE and similar conditional models omit clinically relevant information, such as information about variation in treatments’ effects and the causes of different responses to therapy; and that heuristic approaches lack the necessary empirical support. The conclusion is that hierarchies in general embed untenable philosophical assumptions: principally that information about average treatment effects backed by high-quality evidence can justify strong recommendations, and that the impact of evidence from individual studies can and should be appraised in isolation. Hierarchies are a poor basis for the application of evidence in clinical practice. The Evidence-Based Medicine movement should move beyond them and explore alternative tools for appraising the overall evidence for therapeutic claims. (shrink)

My doctoral project is a study of epistemological and ethical issues in Evidence-Based Medicine, a movement in medicine which emphasizes the use of randomized controlled trials. Much of the research on EBM suggests that, for a large part of the movement's history, EBM considered expertise, mechanisms, and values to be forces contrary to its goals and has sought to remove them, both from medical research and from the clinical encounter. I argue, however, that expertise, mechanisms and values have important epistemological (...) and ethical roles to play and can be incorporated into the current EBM movement. (shrink)

Public health involves the application of a wide variety of scientific and non-scientific disciplines to the very practical problems of improving population health and preventing disease. Public health has received surprisingly little attention from philosophers of science. In this chapter we consider some neglected but important philosophical aspects of the science of public health.