JOURNAL OF PALLIATIVE MEDICINEVolume 11, Number 1, 2008© Mary Ann Liebert, Inc.DOI: 10.1089/jpm.2008.9998

Evidence-Based Medicine and Palliative Care

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WHERE IS YOUR EVIDENCE? Not a bad question, buttoo often the question is used as a weapon,

rather than representing a respectful inquiry. Magrittepaints a picture of a pipe, but then declares that this isnot a pipe. Why? I think Magritte is warning us not toconfuse the image of a thing with its essence. Just so,in palliative care we need to be careful not to confuseevidence with the subject of our interest—especiallywhere we are concerned with suffering and quality oflife.

of their lives. The fundamentally subjective nature ofquality and personhood should give us pause for re-flection. It begs the obvious to point out that most ofus manage to stumble through life reasonably suc-cessfully, making both trivial and difficult decisionsuninformed by randomized controlled trials. Perhapsthere is some method in this madness. Most peoplemake choices based on complex, iterative processes ofexperience and adjustment within esthetic frameworksof likes and dislikes. Such likes and dislikes are in-fluenced by a variety of factors—social, cultural, andhistorical. Choices can certainly be informed by ob-jective data. However, we recognize a basic level ofpersonal esthetics as being valid, despite the fact thatsuch validity is entirely subjective. For example, weaccept as true that some people prefer chocolate overvanilla ice cream. We would not think of doing a studyto determine which is better—chocolate or vanilla icecream—because we recognize differing preferences asbeing equally valid. (However, we could study popu-lation preferences for marketing purposes.) To the ex-tent that the subjective experiences of patients andfamilies are the object of palliative care, we must pro-ceed cautiously. We would all be naturally skeptical,I think, of a science that attempted to capture theessence of even as simple an experience as eating icecream. How much more humble we must be in ap-proaching something as complex as suffering, usingthe scientific method.

A critical literature of evidence-based medicine isbeginning to emerge.1–4 Some criticism questions thedominance of randomized controlled trials (RCTs),commonly put at the top in hierarchies of evidence.5

Advocates for evidence-based medicine within pallia-tive care have noted serious methodologic challengesin performing RCTs in palliative care.6–8,9 Argumentshave also been put forth for the inclusion of more qual-itative and narrative forms of evidence in palliativecare research.9,10 Some writers have warned of thedanger of excessive dependence on population-basedstudies in making decisions regarding individual pa-tients. Dr. David Sackett, acknowledged father of theevidence-based medicine (EBM) movement, and col-leagues have acknowledged the importance of using

Notes from the Editor

FIG. 1. Rene Magritte, surrealist painter.

No one questions the importance of expanding theevidence base for what we do in medicine in general,and palliative care in particular. However, a caution-ary note is in order. Evidence-based methodologies,like all specialized tools, have strengths and weak-nesses. They also may have unintended consequences.I first describe difficulties in trying to apply the evi-dence-based medicine paradigm to palliative care andthen consider the strengths and weaknesses of this ap-proach. Finally, I reflect on the uncomfortable chal-lenges faced by the palliative care researcher, work-ing to discover new knowledge in the context of asocial movement.

Palliative care distinguishes itself from the rest ofmedicine in that it focuses on people and the quality

available evidence in the service of individuals. EBMis defined by them as “the conscientious, explicit andjudicious use of current best evidence in making de-cisions about the care of individual patients.”11 Crit-ics Williams and Garner4 applaud this recognition ofthe importance of clinical judgment, but then complainthat they “did not attempt to define or categorize theelusive quality of clinical competence and the neces-sary balance was endangered further by the evange-lism of some practitioners.” Indeed, they suggest thatEBM has become a belief system unto itself, less con-cerned with thoughtful inquiry than with maintenanceof a new orthodoxy. “This new orthodoxy is leadingto problems in three areas: the macroeconomic of pur-chasing health, the individual transaction between thedoctor and patient; the inhibiting influence of politicalcorrectness.”4 In his popular book on EBM Sackett ad-dressed some “limitations of EBM” on one page in arather perfunctory manner. This is distressing giventhe candid admission by Sackett12(pp6–7) in the secondedition of his book on EBM that there is remarkablylittle evidence that patient outcomes are actually im-proved by its application.

Arthur Kleinman, psychiatrist and anthropologist,has commented on the danger of objectifying suffer-ing, translating this discussion into words familiar tothe world of EBM.13(pp72–75) He points out that we canindeed calculate inter-rater reliability (the extent towhich data are consistent among different observers)relative to episodes of suffering. However, he warnsthat if a common cultural bias shapes the way multi-ple observers perceive a particular event, their obser-vations might be “reliable,” even if far from a rea-sonable representation of reality. The risk of this isparticularly great when the “event” being evaluatedcan only be appreciated subjectively or from within adifferent cultural context than that of the observers.Thus, validity (the extent to which data reflect realityor truth) is more problematic than reliability whendealing with subjective phenomenon; in fact, it will ul-timately elude the researcher. Even if a person says,“Yes, your study tool or observation has exactly cap-tured my suffering,” such communication merely sug-gests that a reasonable image of the experience hasbeen captured, much as Magritte captured the imageof a pipe. The essence of suffering can only be graspedthrough direct experience.

Cultural and political biases may affect not only es-timates of reliability and validity, but may shape thevery questions we choose to ask.13(pp68–92),14 The sci-entific method works to discover and understand newthings. However, the process by which certain ques-tions are attended to and others ignored may in fact

serve to perpetuate and strengthen one particularworld-view at the expense of others.15 Contrary to thedominant myth of science, which stresses objective,dispassionate exploration of the universe simply forthe joy of discovery, real studies are conducted by realpeople in social and political contexts. Fundingsources have agendas, which any potential granteemust consider in drafting proposals if there is any hopeof success. How else can we understand the wealth ofstudies on chemotherapy-related nausea and the ab-sence of one randomized control trial of prometha-zine and prochlorperazine for opioid-related nausea?Schools, academies, and journals will bestow greaterprestige on certain scholarly pursuits than others,thereby influencing investigator choices. Journals willaccept and disseminate certain articles and not others.

The danger in regards to EBM should be clear. Thechoices made in selecting certain studies and estab-lishing a particular evidence base can create a cultureof medicine in which certain aspects of reality are at-tended to and others simply ignored.

As Bradley and Field3,4 put it, “It is a short stepfrom ‘without substantial evidence’ to ‘without sub-stantial value.’”

At the extreme, as some advocates have argued, ifthe only good medicine is EBM, then we risk creatinga culture of medicine in which only objective data arerelevant. Such a culture would have little room for sub-jectivity (at best objectifying such subjectivity throughproxies like utility weights) and could constrain andshape actual, best practices in dangerous ways. Lestone doubt the potential danger, I suggest that the readerpick-up one of the many available handbooks on EBMand scan for topics of interest to palliative care. A BMJClinical Evidence book reviewed contained three ref-erences to palliative care, all for noncurative therapyof cancer, not symptom management. There were noreferences to pain or other common symptoms. Theindex made no reference to suffering; suffering, ap-parently, is not evidence based.16 The first edition ofSackett’s book does make a reference to death—as adefinitive, objective clinical end point that can be mea-sured.17 Neither death nor suffering are referenced inthe second edition of his book.12 Clearly, there is somegood evidence-based literature in palliative care thatmight well have been included in such texts. I fear thatthe noninclusion of evidence-based palliative carework into such texts is not just an oversight, but arisesfrom a narrow world-view, which does not readily ac-knowledge the legitimacy of palliative care con-cerns—precisely because such concerns arise from at-tention to personhood and to suffering.

Those of us doing research in palliative care must

NOTES FROM THE EDITOR 3

also take note of our own biases. Palliative care is notjust an evolving specialty of medicine, it is in part a so-cial movement, working to change medicine. While Ibelieve this is in fact a good, necessary thing, we in-herit a special obligation when engaging “evidence”within a political context. We need to reflect on howour zeal to “change the system” shapes the questionswe ask. Nothing can be as blinding as a passion to provewhat we already “know” to be true.18 Researchers con-ducting studies within overtly political contexts (to dem-onstrate, for example, some obvious care deficiency atthe end of life) have a special obligation to considerdeeply how their biases may shape questions asked andtheir interpretation. At issue is nothing as crude as fal-sification of data. One can be truthful and yet choose,consciously or subconsciously, to highlight some as-pects of studies and not others.

Does this mean that we should discourage or shunevidence-based studies? Certainly not. Does it meanthat it is so impossible to understand the subjective ex-perience of another person that we shouldn’t try?Absolutely not. It does mean that evidence-basedmethodologies are just one set of tools, useful for un-derstanding certain aspects of reality, but not neces-sarily the best for understanding others. The subjec-tive experiences of others may be better understood inother ways.19 The best way to understand ice cream istaste it. Where direct experience is impossible (or un-desirable), perhaps we can find a certain resonancewith people through other means—narratives, story-telling, songs, and other esthetic endeavors, creating ashared and more valid experience that will better serveus in our efforts to serve others.

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2. Goodman N: Who will challenge evidence-based medi-cine? J R Coll Physicians 1999;33:249–251.

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4. Williams DD, Garner J: The case against “the evidence”:A different perspective on evidence-based medicine. Br JPsychiatry 2002;180:8–12.

5. Concato J, Shah N, Horwitz RI: Randomized, controlledtrials, observational studies, and the hierarchy of researchdesigns. N Engl J Med 2000;342:1887–1892.

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11. Sackett DL, Rosenberg WM, Gray JA, Haynes RB,Richardson WS: Evidence based medicine: What it is andwhat it isn’t. BMJ 1996;312:71–72.

12. Sackett DL, Strause S, Richardson WS, Rosenberg WM,Haynes RB: Evidence-Based Medicine, 2nd ed. Edinburgh:Churchill Livingstone, 2000.

13. Kleinman A: Writing in the Margin: Discourse betweenAnthropology and Medicine. Berkeley: University of Cal-ifornia Press, 1995.

14. Kleinman A, Das V, Lock M (eds): Social Suffering. Berke-ley: University of California Press, 1997.

15. Buetow S, Kenealy T: Evidence-based medicine: The needfor a new definition. J Eval Clin Pract 2000;6:85–92.

16. Clinical Evidence, Volume 4. London: BMJ PublishingGroup, 2000.

17. Sackett DL, Strause S, Richardson WS, Rosenberg WM,Haynes RB: Evidence-Based Medicine, 1st ed. Edinburgh:Churchill Livingstone, 1997.

18. von Gunten C: Evidence for our opinions. J Palliat Med2005;8:1084–1085.

19. Wilson H: The myth of objectivity: Is medicine moving to-wards a social constructivist medical paradigm? Fam Pract2000;17:203–209.

Address reprint requests to:James Hallenbeck, M.D.

Division of General Internal MedicineStanford University School of MedicineVA Hospice and Palliative Care Center

3801 Miranda AvenuePalo Alto, CA 94304

E-mail: james.hallenbeck@va.gov

NOTES FROM THE EDITOR4