Non evidence based

Limitations to Evidence Based Practice

THOMAS MAIER

The promotion of evidence-based medicine (EBM) or, more generally, of evidence-based practice (EBP) has strongly characterized most medical disciplines over the past 15 to 20 years. Evidence-based medicine has become a highly influential concept in clinical practice, medical education, research, and health policy. Although the evidence-based approach has also been increasingly applied in related fields such as psychology, education, social work, or economics, it was and still is predominantly used in medicine and nursing. Evidence-based practice is a general and nonspecific concept that aims to improve and specify the way decision makers should make decisions. For this purpose it delineates methods of how professionals should retrieve, summarize, and evaluate the available empirical evidence in order to identify the best possible decision to be taken in a specific situation. So EBP is, in a broader perspective, a method to analyze and evaluate large amounts of statistical and empirical information to understand a particular case. It is therefore not limited to specific areas of science and is potentially applicable in any field of science using statistical and empirical data. Many authors often cite Sackett, Rosenberg, Muir Gray, Haynes, and Richardson’s (1996) article entitled “Evidence-based medicine:What it is and what it isn’t” as the founding deed of evidence-based practice. David L. Sackett (born 1934), an American-born Canadian clinical epidemiologist, was professor at the Department of Clinical Epidemiology and Biostatistics of McMaster University Medical School of Hamilton, Ontario, from 1967 to 1994. During that time, he and his team developed and propagated modern concepts of clinical epidemiology. Sackett later moved to England, and from 1994 to 1999, he headed the National Health Services’ newly founded Centre for Evidence-Based Medicine at Oxford University. During that time, he largely promoted EBM in Europe by publishing articles and textbooks as well as by giving numerous lectures and training courses. David Sackett is seen by many as the founding father of EBM as a proper discipline, although he would not at all claim this position for himself. In fact, Sackett promoted and elaborated concepts that have been described and used by others before; the origins of EBM are rooted back in much earlier times. The foundations of clinical epidemiology were already laid in the 19th century mainly by French, German, and English physicians systematically studying the prevalence and course of diseases and the effects of therapies. As important foundations of the EBMmovement, certainly the works and insights of the Scottish epidemiologist Archibald (Archie) L. Cochrane (1909–1988) have to be c04 18 April 2012; 19:44:27 55 Hersen, Michel, and Peter Sturmey. Handbook of Evidence-Based Practice in Clinical Psychology : Adult Disorders, John Wiley & Sons, Incorporated, 2011. ProQuest Ebook Central, http://ebookcentral.proquest.com/lib/ashford-ebooks/detail.action?docID=817356. Created from ashford-ebooks on 2017-11-07 11:26:43. Copyright © 2011. John Wiley & Sons, Incorporated. All rights reserved. mentioned. Cochrane, probably the true founding father of modern clinical epidemiology, had long before insisted on sound epidemiological data, especially from RCTs, as the gold standard to improve medical practice (Cochrane, 1972). In fact, the evaluation of epidemiological data has always been one of the main sources of information in modern academic medicine, and many of the most spectacular advances of medicine are direct consequences of the application of basic epidemiological principles such as hygiene, aseptic surgery, vaccination, antibiotics, and the identification of cardiovasular and carcinogenic risk factors. One of the most frequent objections against the propagation of EBM is, “It’s nothing new, doctors have done it all the time.” Rangachari, for example, apostrophized EBM as “old French wine with a new Canadian label” (Rangachari, 1997, p. 280) alluding to the French 19th century epidemiology pioneer Pierre Louis, who was an influencing medical teacher in Europe and North America, and to David L. Sackett, the Canadian epidemiologist. Even though the “conscientious, explicit and judicious use of the current best evidence in making decisions about the care of individual patients” (Sackett et al., 1996, p. 71) seemsto be a perfectly reasonable and unassailable goal, EBM has been harshly criticized from the very beginning of its promotion (Berk &Miles Leigh, 1999; B. Cooper, 2003; Miles, Bentley, Polychronis, Grey, and Price, 1999; Norman, 1999; Williams & Garner, 2002). In 1995, for example, the editors of The Lancet chose to publish a rebuking editorial against EBM entitled “Evidence-based medicine, in its place” (The Lancet, 1995): The voice of evidence-based medicine has grown over the past 25 years or so from a subversive whisper to a strident insistence that it is improper to practise medicine of any other kind. Revolutionaries notoriously exaggerate their claims; nonetheless, demands to have evidence-based medicine hallowed as the new orthodoxy have sometimes lacked finesse and balance, and risked antagonising doctors who would otherwise have taken many of its principles to heart. The Lancet applauds practice based on the best available evidence–bringing critically appraised news of such advances to the attention of clinicians is part of what peer-reviewed medical journals do–but we deplore attempts to foist evidencebased medicine on the profession as a discipline in itself. (p. 785) This editorial elicited a fervid debate carried on for months in the letter columns of The Lancet. Indeed, there was a certain doggedness on both sides at that time, astonishing neutral observers and rendering the numerous critics even more suspicious. The advocates of EBM on their part acted with great self-confidence and claimed no less than to establish a new discipline and to put clinical medicine on new fundaments; journals, societies, conferences, and EBM training courses sprang up like mushrooms; soon academic lectures and chairs emerged; however, this clamorous and pert appearance of EBM repelled many. A somehow dogmatic, almost sectarian, tendency of the movement was noticed with discontent, and even the deceased patron saint of EBM, Archie Cochrane, had to be invoked in order to push the zealots back: How would Archie Cochrane view the emerging scene? His contributions are impressive, particularly to the development of epidemiology as a medical science, but would he be happy about all the activities linked with his name? He was a freethinking, iconoclastic individual with a healthy cynicism, who would not accept dogma. He brought an open sceptical approach to medical problems and we think that he would be saddened to find that his name now embodies a new rigid medical orthodoxy while the real impact of his many achievments might be overlooked. (Williams & Garner 2002, p. 10) THE DEMOCRATIZATION OF KNOWLEDGE How could such an emotional controversy arise about the introduction of a scientific 56 Overview and Foundational Issues c04 18 April 2012; 19:44:28 Hersen, Michel, and Peter Sturmey. Handbook of Evidence-Based Practice in Clinical Psychology : Adult Disorders, John Wiley & Sons, Incorporated, 2011. ProQuest Ebook Central, http://ebookcentral.proquest.com/lib/ashford-ebooks/detail.action?docID=817356. Created from ashford-ebooks on 2017-11-07 11:26:43. Copyright © 2011. John Wiley & Sons, Incorporated. All rights reserved. method (Ghali, Saitz, Sargious, & Hershman, 1999)? Obviously, the propagation and refusal of EBM have to be seen not only from a rational scientific standpoint but also from a sociological perspective (Miettinen, 1999; Norman, 1999): The rise of the EBM movement fundamentally reflects current developments in contemporary health care concerning the allocation of information, knowledge, authority, power, and finance (Berk & Miles Leigh, 1999), a process becoming more and more critical during the late 1980s and the 1990s. Medicine has, for quite some time, been losing its prestige as an intangible, moral institution. Its cost-value ratio is questioned more and more and doctors are no longer infallible authorities. We do not trust doctors anymore to know the solution for any problem; they are supposed to prove and to justify what they do and why they do it. These developments in medicine parallel similar tendencies in other social domains and indicate general changes in Western societies’ self-conception. Today we are living in a knowledge society, where knowledge and information is democratized, available and accessible to all. There is no retreat anymore for secret expert knowledge and for hidden esoteric wisdom. The hallmarks of our time are free encyclopedic databases, open access, the World Wide Web, and Google©. In the age of information, there are no limitations for filing, storage, browsing, and scanning of huge amounts of data; however, this requires more and more expert knowledge to handle it. So, paradoxically, EBM represents a new specialized expertise that aims to democratize or even to abolish detached expert knowledge. The democratization of knowledge increasingly questions the authority and selfsufficiency of medical experts and has deeply unsettled many doctors and medical scientists. Of course, this struggle is not simply about authority and truth; it is also about influence, power, and money. For all the unsettled doctors, EBM must have appeared like a guide for the perplexed leading them out of insecurity and doubt. Owing to its paradoxical nature, EBM offers them a new spiritual home of secluded expertise allowing doctors to regain control over the debate and to reclaim authority of interpretation from bold laymen. For this purpose, EBM features and emphasizes the most valuable label of our time that is so believable in science: science- or evidencebased. In many areas of contention, terms like evidence-based or scientifically proven are used for the purpose of putting opponents on the defensive. Nobody is entitled to question a fact, which is declared evidence-based or scientifically proven. By definition, these labels are supposed to convey unquestioned and axiomatic truth. It requires rather complex and elaborate epistemological reasoning to demonstrate how even true evidence-based findings can at the same time be wrong, misleading, and/or useless. All these accounts and arguments apply in particular to the disciplines of psychiatry and clinical psychology, which have always had a marginal position among the apparently respectable disciplines of academic medicine. Psychiatrists and psychologists always felt particularly pressured to justify their actions and are constantly suspected to practice quackery rather than rational science. It is therefore not surprising that among other marginalized professionals, such as the general practitioners, psychiatrists and psychotherapists made particularly great efforts over the last years to establish their disciplines as serious matters of scholarly medicine by diligently adopting the methods of EBM (Geddes & Harrison, 1997; Gray & Pinson, 2003; OakleyBrowne, 2001; Sharpe, Gill, Strain, & Mayou, 1996). Yet, there are also specific problems limiting the applicability of EBP in these disciplines